THE ENIGMATIC KINGDOM OF PLANTS: THEIR POWER TO STIMULATE, INTOXICATE AND ALTER CONSCIOUSNESS; THEIR POWER TO MAIM, KILL AND CURE IBy OLOWOKUDEJOPROFESSOR JAMES DELE PROFESSOR JAMES DELE OLOWOKUDEJO, FLS, FLEAD, FCFIP, FISH B.Sc. Special Honours (Lagos), Ph.D. (Reading, England) Professor of Botany THE ENIGMATIC KINGDOM OF PLANTS: THEIR POWER TO STIMULATE, INTOXICATE AND ALTER CONSCIOUSNESS; THEIR POWER TO MAIM, KILL AND CURE An Inaugural Lecture Delivered at the University of Lagos J.F. Ade. Ajayi Auditorium on Wednesday 10th October 2018 By PROFESSOR JAMES DELE OLOWOKUDEJO B.Se. Special Honours (Lagos), Ph.D. (Reading, England) Professor of Botany Department of Botany Faculty of Science University of Lagos, Akoka, Yaba iii Copyright © 2018, James Dele Olowokudejo All rights reserved. No part of this publication may be reproduced, stored in a .retrieval system or transmitted in any form or by any means electronic, mechanical, photocopying, recording, or otherwise without the permission of the author. ISSN: 1119-4456 Published by University of Lagos Press and Bookshop Ltd Works and Physical Planning Complex P.O. Box 132 University of Lagos Akoka, Yaba Lagos, Nigeria E-mail: press@unilag.edu.ng iv DEDICATION This inaugural lecture is dedicated to the memories of my late Parents, Pa. Isaiah Giwa Adelodun & Chief (Mrs.) Ernilia Eminlola OLOWOKUDEJO, with profound gratitude. v / ,.," .....r...~d.r1~'" c..'..~. PROTOCOL The Vice-Chancellor, Deputy Vice-Chancellor (Management Services), Deputy Vice-Chancellor (Academic and Research), Deputy Vice-Chancellor (Development Services), The Registrar, The Bursar, The University Librarian, The Provost, College of Medicine, The Dean, Faculty of Science, Other Deans of Faculties, Members of the University Senate, Heads of Departments Other Principal Officers of the University, Your Lordships (Temporal and Spiritual), Your Royal Majesties and Highnesses, Distinguished Academic and Professional Colleagues, Non-academic Colleagues (Administrative and Technical), Dear Students (Past and Present), Members of the Press (Print and Electronic Media), Distinguished Ladies and Gentlemen. 1.0 PREAMBLE To God Almighty be the honour and the glory for making today a reality. I had the privilege of receiving a good education and the fortune of an excellent exposure to the best of university culture and traditions, both home and abroad. I secured admission to study Botany at the University of Lagos in August 1972, as a 21-year-old Hiqher School Certificate graduate of Victory College, Ikare-Akoko, Ondo State. The admission letter was delivered through the Post Office Box of my local church in Ikere, Ekiti State, from where I boarded a bus to Lagos to resume studies as a fresher at the University of Lagos, on the 26th of September 1972. I embarked on that fateful journey to Lagos with trepidation because of the horrible reputation of Lagos then, as a city of criminals and fraudsters. I obtained the Bus route numbers of the four Municipal Buses that plied Ojota to Yaba and the two buses that were dedicated to Yaba - University of Lagos axis. The journey was seamless and the 1 experience was life changing. The rest, as it is commonly .said, is history! 2.0 STRUCTURE OF THE LECTURE This Inaugural Lecture is divided into four major segments. The first section shall shed more light on the subject of Botany, its origin, and some of its subdisciplines including re~ent advances and current trends. The power, wonders, mysteries, myths, and relevance of plants in huma~ affairs will b.e presented in the second section. The third segment will highlight some of my research contributions within the general framework of my multidisciplinary training in Plant Taxonomy, Biosystematics, Biodiversity, Conservation, and the Environment. The fourth and last section will draw attention to the fragile and precarious state of the environment and how humans are killing the atmosphere, the land, and the oceans; depleting biodiversity and reducing the earth's capacity to sustain life. The lecture will be concluded by outlining some general and specific recommendations which have both local and global implications. Mr. Vice-Chancellor Sir, the title of the lecture reflects the overwhelming influence and incredible dominance of plants over all other forms of living and non living entities and the environment. I am taking the audience on a tour to the world of plants, and letting all of us see how plants moulded our bodies, faculties, perceptions, and tastes. Either directly, or as the base of a pyramid of consumption; the roots, stems, fruits, and flowers of plants sustain the whole of the animal kingdom. The backdrop to our evolution, they attended the vital needs of all our ancestors - marine, amphibian, and primates - as they indispensably supply ours till today. Therefore, in the end, or rather in the beginning, we are all plants. 3.0 THE SUBJECT OF BOTANY - Definition, Origin & History Botany, also called Plant Science(s), Plant Biology, or Phytology is the science of plant life and a branch of biology. The term "botany" comes from three Ancient Greek words: botanikos (botanical), botane (plant or herb), and boskein (to 2 feed), and the French word botanique (botanical). Botany had its origin from the Stone Age people who tried to modify their surroundings and feed themselves. At first, the interest in plants was mostly practical and centred around how plants might provide food, fibres, fuel, and medicine. Eventually, an intellectual interest arose. Individuals became curious about how plants reproduced and how they were put together. This inquisitiveness led to plant study becoming one of the oldest branches of science, which broadly defined is simply "a search for knowledge of the natural world" (Stern, 2011). Since plant life is so fundamental to human survival, people have been studying plant life from the beginning of recorded time. When people were looking to trees, bushes, and grasses for food, they began to notice where and when these food items would show up. They made the connection between water and plant life, and noticed how soil types controlled the growth of plants. Theophrastus, a Greek philosopher who lived roughly 2300 years ago, is called by many the father of botanical science. His writings on plant classification, patterns of growth, natural locations, and practical applications are considered by many, to be the most important writings on the subject to reach us from ancient times. It was in his days that people of science and thought began to realise the empirical (careful observation) and logical approach that can be taken in the pursuit of scientific knowledge. Much of his writing contained detailed instructions on how to CUltivate and use a wide variety of plants, making his botanical science very practical. In A.D. 60, a Greek physician, Dioscorides wrote a general medical manual, called De Materia Medica., which became the medical guidebook in general practice for over 1500 years. Most of the medicines described in that work are botanical in nature and helped maintain the knowledge and use of non- food plants. Near the beginning of the Renaissance, Theophrastus' writings were rediscovered and circulated, generating anew interest in the scientific study of plants themselves. Beginning from the 17th century, many scientists in the field of botany 3 began to make remarkable discoveries in the history of the I6tudy of plants. As can be deduced, Botany originated in prehistory as herballsm with the efforts of early humans to identify - and later cultivate edible, medicinal, and poisonous plants, making it one of the oldest branches of science. Medieval physic gardens, often attached to monasteries contained plants of medical importance. They wer~ forerunners of the first botanical gardens attached to universltles, founded from 1504 onwards. One of the earliest was the Padua Botanical Garden - the world's oldest academic botanical garden founded in 1545 and still in its pri~i.nal location in northeastern part of Italy. These gardens facilitated the academic study of plants. Efforts to catalogue and describe their collections were the beginnings of plant taxonomy and in 1753, it led to the binomial system of Carl Linnaeus that remains in use to this day. ~.1 Botany Today Modern Botany is a fascinatmq blend of tradition and innovation. In recent times, it has expanded from its traditional base of plant morphology, anatomy, physiology, classification, and distribution, through the application of the most modern experimental techniques such as: scanning and transmission electron microscopy, computer technology, sophisticated analytical procedures, and revolutionary diagnostic techniques, in which short DNA sequences can be used for species identification. These processes involve DNA amplification, Agarose gel electrophoresis, Polymerase Chain Reaction amplification, Cycle Sequencing, Automated sequencing, editing, and alignment of DNA sequences and generation of DNA barcodes. Awareness of the fundamental Importance of plants in our environment has increased rapidly with the realisation that they represent the only truly renewable e~ergy source. Already, plants are being used, not only directly as food, raw materials, and drugs, but increasingly as novel sources of fuel and of chemicals for industry. This has led to the development of new subjects such as genetic engineering and biotechnology, which depend on the studies of plant genetics, physiology, and biochemistry for their success. In addition, the resurgence of interest in medicinal 4 plants, which constitutes an important part of health care system in developing countries, has generated widespread involvement of communities and government in the study, for the efficient utilisation and conservation of these plants. Moreover, biodiversity is fast becoming the key indicator of a healthy planet and healthy society. Furthermore, fundamental botanical research underpins many aspects of agricultural and industrial development such as plant breeding, plant protection, and fertiliser practices. At the same time, research in ecology, taxonomy, and biosystematics is helping us understand how to manage existing plant resources wisely, both for leisure activities and for agriculture, forestry and genetic conservation, all for the benefit of mankind. 3.2 Branches of Botany Over time, as the spirit of enquiry festers and technology grows, there has been a conscious diversification of plant study. These have given rise to several distinct subdisciplines of Botany including: Anatomy, Physiology, Taxonomy/ Systematics, Biosystematics, Molecular Systematics, Morphology, Cytology, Genetics/Cytogenetics, Plant Geography/Biogeography, Ecology, Economic Botany, Ethnobotany, Phytochemistry, Embryology, Algology, Bryology, Mycology/Pathology, Palynology, and Palaeobotany, among others. 3.3 The Kingdom Concept It was natural when classification schemes were first developed, that all living organisms would be placed according to the highest category of Kingdom, in either the Plant Kingdom or the Animal Kingdom. While this distinction still works well for the more complex plants and animals, it breaks down for some of the so-called simpler organisms, e.g. euglenoids, slime moulds, bacteria and others. In various attempts to overcome these problems, biologists have proposed three -, four -, five - and six - kingdom arrangements, as shown in Tables 1&2 below. However, for the purpose of this lecture the old traditional two-kingdom 5 scheme is adopted for clarity, ease of communication, and understanding. The hypothetical derivations and relationships among kingdoms and the major groups of organisms are illustrated in Figure 1. Table 1: Five Classifications of Organisms into Kingdoms TWO THREE FOUR FIVE SIX FEATURES KINGDOMS KINGDOMS KINGDOMS KINGDOMS KINGDOMS (Traditional) (Hogg and (Copeland) (Whittaker) (Woeseetal.) Haeckel) Monera Monera Archaea Cells Bacteria Bacteria Archaebacteria prokaryotic; Lack muramic acid Protoctista Protoctista Protista Bacteria Cells prokaryotic: Bacteria Algae Algae True bacteria have muramic acid Algae Slime molds Slime molds Protista Cells eukaryotic Slime molds Flagellate Flagellate Algae fungi fungi Flagellate True fungi Protozoa Slime molds fungi True fungi Protozoa Sponges Watermolds Protozoa Sponges Protozoa Sponges Sponges Fungi Fungi Absorb food in solution True fungi True fungi Plantae Plantae Plantae Plantae Plantae Produce food via Bac!eria Bryophytes Bryophytes Bryophytes Bryophytes Photosynthesis Algae Vascular Vascular Vascular Vascular plants plants plants plants Slime molds Flagellate fungi True fungi Bryophytes Vascular plants Anlmalla Animalla Anlmalia Animalia Animalla Ingest food Protozoa Multicellular Multicellular Multicellular Multicellular animals animals animals animals Sponges Multicellular animals Source: Stdlack & Jansky, 2011 6 Table 2: Classification of Organisms into Six Kingdoms Domain Archaea Kingdom Archaea Phylum Archaebacteria (methane, salt, and sulfolobus bacteria) Domain Bacteria Kingdom Bacteria Phylum Eubacteria Class Eubacteriae (unpigmented, purple, and green sulfurbacteria Class Cyanobacteriae (cyanobacteria) Class Chloroxybacteriae (chloroxybacteria) Domain Eukarya Kingdom Protista Phylum Chlorophyta (green algae) Phylum Chromophyta (yellow-qrsen, golden-brown, and brown algae) Phylum Rhodophyta (red algae) Phylum Euglenophyta (euglenoids) Phylum Dinophyta (dinoftagellates Phylum Cryptophyta (cryptomonads) Phylum Prymnesiophyta (haptophytes) Phylum Charophyta (stoneworts) Phylum Myxomycota (plasmodial slime molds) Phylum Dictyosteliomycota (cellular slime molds) Phylum Oomycota (water molds) (Phylum Protozoa - protozoans) (Phylum Porifera - sponges) Kingdom Fungi Phylum Chytridiomycota (chytrids) Phylum Zygomycota (coenocytic fungi) Phylum Ascomycota (sac fungi) (Lichens) Phylum Basidiomycota (club fungi) Phylum Deuteromycota (imperfect fungi) Kingdom Plantae Phylum Hepaticophyta (liverworts) Phylum Anthocerotophyta (homworts) Phylum Psilotophyta (whisk ferns) Phylum Bryophyta (mosses) Phylum Lycophyta (club mosses) Phylum Equisetophyta (hosetails) Phylum Polypodiophyta (ferns) Phylum Pinophyta (conifers) Phylum Ginkgophyta(Ginkgo) Phylum Cycadophyta (cycads) Phylum Gnetophyta (Gnetum, Ephedra, We/witschia) Phylum Magnoliophyta (flowering plants) Class Magnoliopsida (dicots) Class Liliopsida (monocots) Kingdom Animalia (multicellular animals) Source: Sidlack & Jansky, 2011 7 Figure 1: Hypothetical Derivations and Relationships among kingdoms and the Major Groups of Organisms Source: Sidlack & Jansky, 2011 4.0 THE POWER OF PLANTS Millions of years ago, it was the rise of plant life that boosted the stock of oxygen in the atmosphere from a trace gas to the one-fifth proportion that fostered the outburst of animal life. Without the green mantie for our planet, supplied by over 300,000 plant species, animal life as we know it (including Homo sapiens) would never have evolved. Some biologists believe that the demise of one plant species may eventually 8 lead to the extinction of up to 30 animal species, as the consequences reverberate up the food chains. Plants convert sunlight into the stored chemical energy on which all animal life depend on for food (and humans for fuel too). The enormous diversity of plants offers adaptations to every conceivable environment, from desert to tundra, the tropics having the richest speciation. We depend on this green wealth at every turn - from indirect benefits for soil and climate to direct supplies to our tables, factories, and hospitals. Plants are the foundation of all existence, of humans and animals, of society and civilisation. In order to nourish, cure, delight, and inspire us, they battle constantly with the elements. Plants have launched men on the most momentous voyages of discovery, across oceans and continents, and through the inner empires of the mind. Plants create most of our reality and many of our dreams. They are the source of our nourishment and health, pleasures and ecstasies; they sustain religions, cultures, and civilisations. In the end, they can kill and return us to the soil on which they themselves feed. A standard distinction between plants and animals is that the former is static, while the latter is freely mobile. Yet, animals and people are free to roam only within the limits plants allow them, and plants themselves are seldom motionless. They cannot afford to be. Every change in their environment affects them acutely. All parts of a plant constantly respond to each other and to the conditions around them - to light, warmth, moisture, air pressure, touch, temperatures, the position of the sun, and the direction of the wind. Rooted to the spot, they present a picture of rest which is belied by their internal mechanics. Science is still baffled by the series of incredibly complex adjustments that enable a sunflower (Helianthus annuus) to faithfully keep its face to the sun, traversing a broad ellipse throughout the hours of light. Nor can botanists fully understand the protective upheavals in, say, a coltsfoot, when sudden rain threatens to swamp the cosmetic gadgetry of scent and colour. This warding off of rain is one of the hiccups of plant life - responses to particular and unpredictable change (Lehan, 1977). Beneath such actions 9 lies the more regular programming, the series of responses to the elemental cycles of night and day, and the succeeding seasons of each year. In the tropics, we talk of dry and wet/rainy seasons, while in temperate regions it is either spring, summer, autumn/fall, or winter. Plants are fully aware of all these seasons. Within every seed of a fruit, sometimes within every cell of a leaf, sits the blueprint for the species' survival. The bare stems of a tree in winter; the buds, shoots and flowers of spring; the denser foliage of summer; and the fruitfulness of autumn; form a predestined pattern within the gene. Every plant knows what is generally required of it. And there is more than these outward and visible signs of growth. Beneath the skeletal profiles of winter, there is unceasing activity within the earth. Along with routine maintenance goes the construction of the leaves and shoots which must break ground, with unerring timing, when the year's worst privations are over. The shoots emerge primed with a vast store of knowledge - about how tall to grow, at what point to branch, when to develop leaf, what forms to assume in each of these particulars, down to the last vein on the leaf and last bristle on its perimeter (Lehan, 1977). 4.1 Photosynthesis This is the most important process on earth for life as we know it. Life on earth depends on it to provide oxygen and absorb carbon (IV) oxide. It is also the foundation through which carbon enters the web of life, directly or indirectly providing food and shelter for most living organisms. By means of plants, the rays of the sun are transformed into flesh. Alone of all life-forms, plants can not only catch sunlight but - by a unique alchemy - compound it with terrestrial ingredients to make the basic food and substance of all living things. Oil and coal today provide about 90% of the energy needed to power trains, trucks, ships, aeroplanes, factories, computers, communication systems, and a multitude of electrically energised appliances. The energy within that oil and coal was originally captured from the sun by plants (including algae) growing millions of years ago and then transformed into fossil fuels by geological forces. However, the energy needs of 10 transportation, industry, and homes seem insignificant, ~~en compared with the combined energy requireme.nts of all Iivl~g organisms. Every living cell requires energy Just to remain alive and more energy is needed for the cell to reproduce, grow' or do physical work as part of an organism. In addition, oxygen is vital to nearly all life in processes that release stored energy. Photosynthesis, at least indirectly, is not only the principal means of keeping all forms of humanity functioning, but also the sole means of sustaining life at any level - except for a few bacteria that derive their energy from sulphur salts and other inorganic compounds. This unique manufacturing process of green plants furnishes raw material, energy, and oxygen .. In photosynthesis, energy from the sun is harne~sed, and with the aid of chlorophyll, it is transformed from light energy to biochemical energy in the bonds between the atoms of a sugar molecule. Oxygen is given off as a by-product of the process. It has been estimated that all of the world's green organisms (including those in the oceans) together produce beh~~en 100 billions and 200 billion metric tons (between 110 billion and 220 billion tons) of sugar each year (Stein, 2011). To visualise that much sugar, consider that it is enough to make. ~bout 3~0 quadrillion sugar cubes (one quadrillion IS 1,000,000,000,000,000). Much of the sugar produce.d by plants is converted to wood, fibres (such as cotton and linen), and other structural materials. The first products of photosynthesis may also be converted to disaccharides, such as sucrose; polysaccharides, such as starch; and other storage forms of carbohydrates. The digestive activities of living organisms break down the carbohydrates to smaller molecules. Sugars produced by photosynthesis are also involved in the synthesis of amino acids for proteins and a host of other cell constituents. In fact, photosynthesis produces more than 94% of the dry weight of green organisms, with the remainder coming from the soil or dissolved matter. The capacity of plants to meet our energy needs may well determine the ultimate size of human populations. In some 11 heavily populated parts of the world. the food supply already is falling short of providing enough energy to sustain life. and starvation is widespread. Meanwhile. in the Western world. significant numbers of persons consume too much food and are spending a lot of money on weight reduction. We will. however. eventually approach a point at which human populations. in general. will need to stabilise else. those in the most affluent areas could exceed the capacity of the plants to sustain them. A great deal of photosynthesis occurs in organisms living in the oceans. It is estimated that between 40% and 50% of the oxygen in the atmosphere originates in oceans and lakes. 4.2 Additional Metabolic Pathways While photosynthesis and respiration are the main processes through which plants grow. develop. reproduce. and survive. there are many other additional processes that contribute toward these activities. Most of these use intermediate steps. but they could not function without photosynthesis and respiration. Some of the essential compounds produced from additional pathways include sugars. phosphates and nucleotides, nucleic acids. amino acids. proteins. chlorophylls. cytochrornes, carotenoids. fatty acids. oils. and waxes. Metabolic processes not required for normal growth and development are generally referred to as secondary metabolism. Although not essential. many of the products from secondary metabolism enable plants to survive and persist under special conditions. These products provide the plant with unique colours, aromas, poisons. and other compounds that may attract or deter other organisms or give them a competitive edge in nature. Humans have exploited many secondary compounds from plants for medicinal. culinary or other purposes. It has been estimated that from 50.000 to 100.000 such compounds exist in plants. with only a few thousands of these thus far having been identified. Secondary metabolic products may be derived from a modification of amino acids and related compounds to produce alkaloids. or through specialised conversions such as the 12 shikimic acid pathway (phenolics) and mevalonic acid pathway (terpenoids). Examples of these compounds are shown in Table 3. Lignin. which is a component of secondary cell walls, is, for example. synthesised through the shikimic acid pathway. Because it is hard to digest and is toxic to some predators, it protects plants from herbivorous animals. Table 3 Examp es of Plant Secondary Compounds Compound Example Source Human Use ALKALOIDS Codeine Opium poppy Nicotine Tobacco Quinine Quinine tree PHENOLlCS Lignin Woody plants Salicin Willow tree Tetrahydrocannabinol Marijuana TERPENOIDS Camphor Camphor tree Menthol Mints and eucalyptus tree Rubber Rubber tree Narcotic pain reliever, cough suppressant Narcotic; stimulant Used to treat malaria Used for hardwood furniture and baseball bats Aspirin precursor Treatment for glaucoma; nausea suppressant Component of medicinal oils and disinfectants Strong aroma; used in cough medicines Rubber tyres, rubber bands, and other commercial products Wherever there is greenery. photosynthesis is working to make oxygen, release energy. and create living matter from the raw material of sunlight. water, and carbon dioxide. Without photosynthesis, there would be an empty world, an empty sky, and a sun that does nothing other than warm the rocks and reflects off the seas. 13 4.3 Dependence of Human and Animal on Plants Humans and animals depend on green organisms to produce the oxygen in the air that we breathe and to remove the carbon dioxide we give off. Plant life constitutes more than 98% of the total biomass (collective dry weight of living organisms) of the earth. Plants and other green organisms have the exclusive capacity to produce oxygen, while converting the sun's energy into forms vital to the existence of both plant and animal life. At the same time, plants remove the large amounts of carbon dioxide given off by all living organisms as they respire. In other words, virtually all living organisms are totally dependent on green organisms for their existence. If some major disease were to kill all or most of the green organisms on land, in the oceans, and lakes, all the animals in these habitats would starve to death. Even if some alternative sources of energy were available, animal life would suffocate within 11 years - the time estimated for all the earth's oxygen to be completely used up if it were not replaced. Plants are also the source of products that are so much a part of human society that we largely take them for granted. We know, of course, that rice, corn, potatoes, and other vegetables are plants; but all foods, including: meat, fish, poultry, eggs, cheese, and milk, to mention just a few, owe their existence to plants. Condiments such as spices, and < luxuries such as perfumes, are produced by plants. So also .' ' are dyes, adhesives, digestible surgical stitching fibre, food . stabilisers, beverages and emulsifiers. Our houses are constructed with lumber from trees, which also furnish the cellulose for paper, cardboard, and synthetic fibres. Some of our clothing, camping equipment, beddings, draperies, and other textile goods, are made from fibers of many different plant families. Coal is fossilised plant material, and oil probably came from microscopic green organisms or animals that were either directly or indirectly plant consumers. All medicines and drugs at one time came from plants, fungi, or bacteria, and many important ones including most of the antibiotics, still do. Microscopic organisms play a vital role in recycling both plant 14 and animal wastes, and aid in the building of healthy soils. Others are responsible for human diseases and allergies. +. Potatoes, grains, and other sources of carbohydrates are currently used in the manufacture of alcohols, some of which are being blended with gasoline ("gasohol"), and such uses probably will increase in the future. Although, there are approximately 250,000 species of flowering plants, only six species - wheat, rice, corn, potato, sweet potato, and cassava - provide 80% of the calories consumed by humans worldwide. An additional eight plants - sugar cane, sugar beet, bean, soybean, barley, sorghum, coconut, and banana - complete the list of major crops grown for human consumption. T bl 4 S' M' C C db H W Id ida e IX ajor rops onsume )y umans or WI e SIN Common Name Botanical Name Family 1. Wheat Triticum aestivum L. Poaceae 2. Rice Orvze sativa L. Poaceae 3. Corn Zea mavs L. Poaceae 4. Potato Solanum tuberosum L. Solanaceae 5. Sweet potato Ipomoea batatas (L.) Poir Convolvulaceae 6. Cassava Manihot esculenta Crantz Euphorbiaceae Table 5: Additional Eight Plants Grown for Human Consurnption SIN Common Name Botanical Name Familv 1. Suoarcane Saccharum officina rum L. Poaceae 2. Wild beet Beta vulgaris L. Chenopodiaceae 3. Bean Phaseolus vulgaris L. Fabaceae 4. Sovbean Givcine max (L.) Merr. Fabaceae 5. Barlev Hordeum vulaare L. Poaceae 6. Sorghum Sorghum bicolor (L.) Poaceae Moench 7. Coconut Cocos nucifera L. Arecaceae 8. Banana Musa acuminata Colla Musaceae In the two million years that we have inhabited this earth, we have cultivated plants for only the most recent 10,000 years, or less than 1% of our history. However, in that time, we have dramatically changed the plant landscape and our own lives. Hunter-gatherer societies have given way to agricultural' societies and the development of cities and 15 civilisation. Such concentrations of people are vulnerable to catastrophes such as drought and famine. Domesticated plants depend on us for their survival, but we have also become dependent on them for our survival. We domesticate plants by altering them genetically to meet our needs. A domesticated plant is one whose reproductive success .depends on human intervention. This is an ongoing evolutionary process, and plants are found in a continuum from purely wild to fully domesticated. Our current crop plants continue to evolve as a result of our breeding efforts. It is amazing that, although humans have eaten thousands of types of plants in the past, we currently rely on only a handful to supply almost all our nutritional needs. 5.0 POWER TO STIMULATE, INTOXICATE, DEPRESS AND ALTER CONSCIOUSNESS Tea and coffee stimulate the mind, trespassing - however softly - on that inner part of man which is seen as his private inalienable core. What some people prohibit, however, most others enjoy as a mild fillip in the day's routine, drinking - without obvious decline - some hundred thousand cups of one or the other beverage in a lifetime. Certainly, these and other plant based drinks have a hold on us, a hold which has had its effect on history. Some plant stimulants burnish the emotion, giving joy, merriment, wonder, and nostalgia a greater intensity. Some appear to quicken the wits, or sharpen desire, or enhance sensual pleasure. Some bring drowsy forgetfulness, sleep, and visions. Certain plants that are involved in this scenario are the hallucinogens plants with constituents which change human perception into a faculty that seems quite remote from normal observation. When we eat a plant or drink an infusion made from it, we are taking in substances which have a chemical effect on, among other things - the physical complexities of our brains. Some of these chemicals have not been isolated, and the means whereby they act on the brain are seldom thoroughly understood. It seems that the process is often the negative one of suppressing some neural reactions, so that others are highlighted in a way which can affect the subject's emotional states. Intoxication by alcohol is an example. 16 Hallucinogens may be subject to the same rules but their effects are usually more interesting and dramatic than those of other drugs, and more ambitious claims have been made on their behalf. The spiritual and theological aspects of religions may well have been born out of the powers of these plants. The magic mushrooms of Mexico, the soma of ancient India, and the Amanita muscaria which was, some claim, were crucial to the religions which went before and perhaps gave rise to some aspects of Christianity-all these were not only aids to worship but, in themselves, objects of worship (Lehane, 1977). Intensive research into these plants over the last four decades, and into their use among primitive people, has stressed that many rituals, lore, and behaviour are still influenced, in a way which earlier observers failed to notice, by insights and visions vouch-safed by consumption of the plants. And it was indicated that much religion, ritual, and lore in advanced societies stems from similar consumption - with its consequent insights and visions in the forgotten past. Indeed, there is no area of the inhabited world in which plants have not made it possible to alter the state of human consciousness to such an extent that people feel they have actually departed from the tiresome realities of the workaday world. The various plant species involved in changing the state of consciousness are called "Psychoactive" plants, which act on the central nervous system. They are divided into three broad categories: • Stimulants, which excite and enhance psychomotor activity; • Hallucinogens, which are capable of inducing a dreamlike state, as well as hallucinations; and • Depressants, which reduce mental and physical performance. A wide range of plant derivatives is involved in the production of these mind-altering drugs. Cocaine, coffee, and tea are well-known stimulants; peyate, certain mushrooms, morning glory seeds, and marijuana (hemp) are frequently used hallucinogens; while alcohol and tranquillisers are the best 17 known examples of depressants. Nicotine obtained from smoking, chewing and sniffing tobacco may act as a depressant, but it serves usually as a stimulant. 5.1 Stimulants Stimulants have long been enjoyed by man. They give him a sense of well-being and exhilaration, self-confidence and power, and they alleviate fatigue and drowsiness. However, the inevitable prices to be paid include: increased agitation, apprehension and anxiety, mild mania (flight of ideas), as well as increased tolerance and often dependency, which are direct results of using stimulants. Two of the most powerful natural stimulants are Coca (Erythroxylum coca) and Chat (Catha edulis). Coca is a native to the Andes area of South America and an extract of coca, well-known as cocaine. It has been available since the 19th Century, but then only for medicinal purposes and, to the few who could afford it, for pleasure. The other stimulant is chat, which is commonly used in eastern Ethiopia and neighbouring countries where it is known as "flower of paradise" (Lewis & Elvin-Lewis, 1977). In addition, there are mild beverage stimulants containing caffeine, theobromine, theophylline, and other alkaloids (Table 6). Table 6: Mildly Stimulating Beverages Containing Xanthine Alkaloids (Lewis & Elvin-Lewis, 1977) Angiospenn family Vernacular Alkaloid Remarks and species Name AQUIFOLlACEAE liex paraguensis Yerba to 2% Leaves for Paraguay tea mate Caffeine or mate in Central America, much cultivated in Northern Argentina to Southern Mato Grosso (Brazil) I. amara, I. Caffeine Species widely conocarpa substituted in Mate I. pseudobuxus, I. theezans I. cassine Dahoon Caffeine Leaves sold for tea in holly, Southern I. vomitoria Cassina North America: especially popular durino Civil War 18 when the South was blockaded; long used by Creek and other Indians as beverage and for ceremonials I. opaca American Dried leaves substituted Holly for tea in Eastern North America during Civil War; probably little or no caffeine MELATOMATACEAE Miconiawilldenowii 0.2% Leaves for tea in Brazil Caffeine RUBIACEAE Coffee arabica Arabian 1-2% Seed roasted, the widely coffee Caffeine cultivated coffee in South and Central America, Eastern Africa: native to the highlands of Eastern Africa C. excelsa, C. Caffeine Western Africa and liberica, cultivated, often grown in lower, more tropical elevations than C. arabica C. maclaudii C. robusta c. stenophylia and others SAPINDACEAE Paulliniacupana Guarana 2.5-5% In Brazil, a paste from Caffeine pulverised seeds mixed with cassava is dried into bars and used as needed in beverage. It also contains 5% tannin; alcoholic drink prepared from seeds and cassava P.yoco 2.8% Beverage in Colombia Caffeine chiefly from bark STERCULlACEAE Cola acuminate Cola +2.5% Cola nuts (seeds) infusion Cola nitida Caffeine for stimulating tea in Western Africa and cultivated throughout tropics; seeds also chewed; popular chewing stick; ingredient of cola soft drink beverages (CocaCola, Pepsi-Cola) 19 Theobroma cacao Cacao (minute) Seeds long use as a tree caffeine: to beverage among Mexican L 3% Indians, native to tropical theobromine America, widely cultivated especially in Western Africa, source of powdered chocolate, cocoa THEACEAE Camellia sinensis Tea 1-4% Of Asian origin and widely Caffeine cultivated since ancient (small) times for dry tea leaf theophylline ~ C. kissi Caffeine Leaves for tea in the and Himalayan region - theophylline Lurvatheoides Leaves for tea in Cuba 5.2 Hallucinogens These are unique compounds. In nontoxic doses, they produce changes in perception, thought, and mood, without causing major disturbances of the autonomic nervous system. Psychic changes and abnormal states of consciousness induced by hallucinogens differ utterly from ordinary experiences. The user of hallucinogens forsakes the familiar world and, in full consciousness, embraces a quasidream world operating under other standards, strange dimensions, and in a different time. These drugs are a means of escaping from reality as it is commonly understood. Most hallucinogens are of plant origin. A few are found among animals; e.g. taraxein, a substance producing schizophrenia, is the only hallucinogen extracted from humans (Hoffer & Osmond, 1967). They do not occur at random throughout the plant kingdom, but rather are dispersed among two groups only - the fungi and, more commonly, the flowering plants, as shown in Table 7. Hallucinogens are found in these well-known plant families, Loganiaceae, Rubiaceae, Apocynaceae, Acanthaceae, Solanaceae, and Convolvulaceae. Large members of these families are concentrated in the New World, in Mexico, and in northern South America, where the use of hallucinogens has 20 deep traditional roots among the indigenous populations. Just as plants having hallucinogens are not found at random and the number of taxa involved is limited, the compounds responsible for hallucinations are composed of very few chemical types. Most are nitrogen-containing compounds, thus, alkaloids. The alkaloids include the protoalkaloids or amino alkaloids, which lack nitrogen in their central structure though usually not in the side chains, and the more complex alkaloids, having nitrogen in their heterocyclic ring structure. The majority of the latter are indoles derived from tryptamines. Table 7: Plants of Hallucinoaenic Use Plant Group and Vernacular Hallucinogenic Comments Species Name Principle FUNGI: ,~COMYCETES Clavicepitales 7-. id Visual fialluClnations: St:-""CiiViceps Ergot -Lyserqic aCI purpurea amide Anthony's fire from other 'FuNGI: ergot alkaloids BASIDIOMYC~ - 1-l--.byccwerdales Lycoperdon Puffballs Unknown Auditory hallucinations marginatum, L. characterise intoxication as experienced by the Mixtecs (Oaxaca, Mexico) Agaricales ,..(Mushroom) Amanita muscaria Fly agaric Ibotenic acid, Major hallucinogen of muscimol Burasia in times gone bv '-Conocybe Psilocybin, psilocin Sacred mushrooms cvanODUS (I ennanactn of Mexico C. siliginoides t-c;ymnopilus ~tabalis Panaceolus sphinotrinus, P tus Psilocybe ~ima, P. aztecorum, P. baesvstls P. caerulescens P. caerulescens P. cordispora '-pTagicola P. hoogshagenii ,~-P. isaurl 21 P. mexicana Stropharia cubensis ANGIOSPERMS -Annonales -MYRISTICACEAE - -Mytistica fragrans Nutmeg and Nonnitrogenous mace Phenylpropenes Aromatic fraction --- Possibly a synergism Between elemicin - Myristicin, and safrole -1- CANNABACEAE Cannabis sativa Hemp, Nonnitrogenous di- (+ C. indica, marihuana, benzopyrans: C. ruderalis hashish, trahydrocannabinol bhang anxiety tin whites); stimulant and aphrodisiac ACANTHACEAE Pulverized leaves addedJusticia pectoralis N. N- Dimethyltryptamine to var. stenophylla Virola, hallucinogenic snuff 1- in Colombia and adjacent Brazil- SOLANACEAE Hallucinations --Atropa belladonna Belladonna Hyoscyamine, scopolamine sometimes and other alkaloids occur largely because of Sco polamine: ingredient of magic brews of middle ages Brunfelsia spp. Alkaloid components Hallucinogenic drink from ~ not well leaves and bark in characterized tropical South America, may be added to ayahuasca (Banisteriopsis) Cestrum Dama Unknown (contain Reputedly sold in ports laevigatum, da noite saponins, gitogenin, of southern Brazil as a C. parqui and digitogenin, substi- C. parqui the tute for marijuana steroidal alkaloid solasonine -Pulverized seeds in tenmen- 22 Ted drinks, or infusion - ofDatura spp. Scopolamine and Leaves and twigs lead other to tropane alkaloids intoxication and hallucination . Hyoscyamus Henbane Hyoscyamine, Ingredients of magic ~ niger, scopola- and H. muticus mine, and other witches brews of earlier - alkaloids days producing visual hallucina- tions and flights of fancyRUBIACEAE /1 ~ Mitragyna Mitragynine, a Intoxicants in southeastspeciosa - hanmine Asia, analog N,N- hallucinogenic in large ~ Dimethyltry- dosesPsychotria Ptamine Added to ayahuasca to en- catharginensis, hance hallucinogenic beve-P. viridis rage CONVOLVULACE AE Argyreia nervosa Wood rose Ergoline alkaloids Seeds contain 3mg of alka- loidal material per gramIpomoea violacea Morning D-Lysergic acid Seeds - tlitlitzen- have glory amide long ~(ergine); other" use in Mexico as ergot" hallucino- --alkaloids maybe gen active Rivea corymbosa Morning As for Ipomoea Seeds - ololiuqui -as glory halluci- nocen in Mexico 5.3 Depressants' A number of drugs that act to depress the central nervous system produce effects of euphoria and well-being, beginning with sedation (calming, tranquilising), followed by hypnosis (sleep), general anaesthesia, and coma, and ending with death from respiratory failure as the dose increases to higher levels. When controlled, all are enormously useful drugs in medicine and society, but all are subject to abuse. With depressant, drugs abuse may lead to addiction, a compulsion 23 characterised by three features: a tendency to increase the dose because tolerance develops, the appearance of physiological changes when drug use is discontinued (i.e., withdrawal symptoms occur), and a strong desire to continue taking the drug (Ray, 1972). This addictive property of many depressants, which include alcohol, barbiturates, tranquilisers and opium, and its derivatives morphine, heroin, and methadone, is their great danger to mankind. 5.4 Alcohol Alcohol in several forms - such as beer from cereals, wine from fruits and berries (Table 8), and mead from honey - was well known by the beginning of recorded history. Some authorities suggest that mead, possibly the oldest of alcoholic beverages, appeared during the Paleolithic Age (ca. 8000 BC), and unquestionably man has indulged in alcohol for religious, social, and medicinal purposes ever since (Lewis & Elvin - Lewis, 1977). \ M~.dicinal use by the Egyptians is recorded among the papyri, w~lch attest to the use of beer and wine as vehicles for other mediclnes. and as tranquilisers and soporifics. Once distillation had been developed by the Moslems, many of the distillates, such as brandy from wine and whisky from beer, were mixed wlith sweeteners and herbs for use by physicians to counter a variety of illnesses. Ethanol was the potent constituent in many such concoctions, causing recognisable physiological effects of relaxation and tranquillity, and its effective role in these and numerous patent medicines of today must not be discounted. Alcohol has numerous other uses: as a solvent to remove oils such as those from poison ivy, as an evaporator to cool the skin during fevers, as a disinfectant, as a pain reliever, as an appetite stimulator, and as a treatment for the common cold. Most alcoholic drinks or beverages are not consumed for medicinal purposes, however, but for pleasure and solace in this hectic world, where hundreds of millions drink liquor, beer, or wine; however several millions have become enslaved by alcohol. 24 Table 8: Some Plant Sources of Alcoholic Drinks (Beer, Wine, Spirits etc.) Cereals SIN Common Name Scientific Name 1. Wheat Triticum aestivum 2. Rice Oryza sativa 3. Maize Zea mays 4. Guinea corn Sorghum bicolor 5. Barley Hordeum vulgare 6. Millet Pennisetum nigritatum 7. Rye Secale cereale (over 20,000 varieties) B. Oats A vena sativa Fruits SIN Common Name Scientific Name 1. Oil palm Elaeis guineensis 2. Raphia palm Raphia farinifera 3. Kola nut (two cotyledons) Cola nitida 4. Kola nut (> two Cola acuminata cotyledons) r- Plantain Musa paradisiacao. 6. Banana Musa acuminata 7. Mango Mangifera indica B. Grapes (table wine) Vitis vinifera 9. Graoefruit Citrus paradisi Alcoholic Beverages The basis of all alcoholic beverages is fermentation, the chemical action of yeast (commonly known as Saccharomyces cerevisiae) acting on sugar in the presence of water. Yeast recombines the carbon, hydrogen, and oxygen of sugar and water into ethyl alcohol (ethanol, C2HsOH) and carbon dioxide. The source of sugar is mostly fruits, especially grapes, or malted barley (sprouted grain that when killed retains the enzymes necessary to convert the starch of grains and mashes to sugar). The appropriate yeasts, often widespread wherever the grapes or other plants grow, are selected for their tolerance to the alcohol they metabolise, which normally has an upper limit of about 15%. In order to obtain alcohol at concentrations higher than that produced by fermentation, alcohol is heated and vapours are collected and condensed into liquid again, in a process known as distillation. This 25 increases the percentage of alcohol, because the distillate h a lower boiling point than water, and thus becomes mo'r conc~ntrated in the condensed liquid than in the origin I ~olutlon. When man mastered the process of distillation h Incr~ased to five .the basic forms of alcoholic beverage ~vallable: table Wines, fortified or dessert wines beers liqueurs, and distilled beverages (spirits) (Table 9).' , Table 9: Examples of Plants Used as Carbohydrate Sources in M ki AIa rng coholic Beveraqes for Domestic Use Plant Group and Species Localitv Remarks RED ALGA Rhodymenia palmata Kamchatka, Natives use this seaweed Siberia as a base FUNGUS Fomesauberianus Tropics Intoxicants, also cause fits and frenzy ANGIOSPERMS ANACARDIACEAE South AfricaSclerocarya caffra S. schwein furthii Tropical Africa Fruit is used to prepare a beerlike beveraae APIACEAE Eastem Europe In Slavic countries boiled Heracleum sphondy/ium leaves and fruit are used to prepare Bartsch ARECACEAE South Africa Stem sap (this and other Hyphaene crinata species of palm widely used) ELAEAGNACEAE Elaeagnus multiflora Japan Fruit FABACEAE Brazil Seed pulp Hymenae acourbaril Argentina Fruit Prosopis nigra Southwestern Fruit used by Indians P.pubescens United States and Mexico RHAMNACEAE Zizyphus abyssinica Malawi Fruit for potent alcoholic beveraoes SAPINDACEAE Paullinia cupana Guarana, Brazil Seeds mixed with cassava and water 26 ffects of Alcohol When alcohol reaches the central nervous system, it slows or .mesthetises brain activity. Though alcohol is a depressant, the initial feeling created is just the opposite, as the barriers of elf-control are lifted and the drinker acts or speaks in ways that his well trained sober self normally forbids. After a number of drinks, the motor centres of the brain are affected, causing clumsiness and unsteadiness in movements. Other effects on those who overindulge include nausea, upset stomach, headaches, and hangover. Withdrawal from alcohol may involve tremors, seizures, visual or auditory hallucinations or both, delirium tremens (frenzied excitement with tremors), and blackouts. 5.5 Tranquilisers Like alcohol and the barbiturates, tranquilisers depress the central nervous system, relieve tension and anxiety, and sometimes relax the skeletal muscles. The first tranquiliser was found in Rauvolfia serpentina (Apocynaceae), which proved to be an indole alkaloid reserpine. Whenever Mahatma Gandhi felt the need to induce a state of philosophic detachment, he sipped tea brewed from the leaves of the plant that grows wild in India and in most of the world's tropical lands. For centuries, the plant was widely used for its calming effect. Holy men chewed it while meditating. Native medicine men employed it to treat highly agitated mental patients. It was even used to soothe fretful babies. Today the drug is not much used in mental health therapy, but it remains an important drug employed in the relief of a major killer, high blood pressure. 5.6 Kava For a very long time, the natives of the South Pacific islands used the rhizomes and roots of Piper methysticum (Piperaceae) or kava to make a beverage that relaxed body and mind, induced refreshing sleep, and eased the pain. The rootstocks are initially handled in two ways: (a) they are reduced to fragments and chewed to a soft mass with saliva, the liquid is mixed with cold water or coconut milk, and the foamy liquid is strained and consumed a few hours later; (b) 27 they are grated and macerated in cold water or coconut mll~, and the liquid is filtered before drinking. The kava prepared by che~ing has a narcotic effect. It paralyses muscl , particularly the lower limbs; it increases the force, but decreases the rapidity of the hearts' action; and it at fir t stimulates, then depresses respiration. Unlike alcohol, th drug does not impair mental alertness. A small quantity giv rise to a euphoric state of short duration characterised by tranquillity and friendliness. Chewed kava is a cerebr I depressant; the drug apparently steadies the pulse, does not raise body temperature, is diaphoretic, and counteract obesity. The deep, dreamless sleep from kava is not followed by a hangover. However, the substance is addicting, and with continuous use, many natives, as well as patients using the extract dihydromethysticin, develop exfoliative dermatitis (Keller &Klohs, 1963). From the root of kava have been isolated methysticin, yangonin, dihydromethysticin, and dihydrokawain, mostly lactones and resins variously estimated at between 3 and 4% of the root (Lewis & Elvin - Lewis, 1977). 5.7 Opiates Opium is a powerful drug derived from the poppy Papaver somniferum, native to the Middle East. If its capsule is cut between the time the petals drop and before the capsule matures - a period of about 10 days during the year-long growth of this annual - a milky sap emerges. When left in the open, the sap dries into the brown, gummy substance known as opium. Throughout history, opium has been a servant to man and many men have also been dependents and addicted servants of opium. Opium is possibly the oldest narcotic known, as early as 4000 BC. The Sumerians referred to it as the joy plant. The drug was used medicinally in ancient Greece and Rome, and Arabian traders introduced it into China. During the Mfddle Ages, a variety of opium preparations appeared in the form of a laudanum or tincture (opium in about 10% ethanol) to ease pain and to create general euphoria. Thus, the stage was set for the popularity of patent medicines containing opium in the 19th century. 28 In Europe, opium had by this time become wide~pread and popular. Notable writers, such as Thomas De Ouincey, who was addicted by the age of 20 after initially using a laudanum to dull the pain of a toothache, wrote: "Opium gives and takes away. It defeats the steady habit of exertion; but it crea~es spasms of irregular exertion. It ruins the natural power of life; but it develops preternatural paroxysms of intermitting power" (Confessions of an English Opium - Eater, 1~21).Several historical and significant events centred on opium occurred between China, Britain, India, and the United States of America, including the concession of Hong Kong Island to the British by the Chinese emperor. Of the more than 25 alkaloids obtained from opium and its extracts, the most important are morphine (4 - 21%), c?deine (0.8 - 2.5%), noscapine or narcotine (4 - 8%), p~p~~erlne(0.5 _ 2.5%), and thebaine (0.5 - 2%). The most slg~lflcant a~e: morphine and its salts, which are strongly an~lgeslc, hypn~tlc, and narcotic. Heroin, formed by the acetylation of morphine, has similar but more pronounced action. Isolated in 1803, morphine came into general use as a painkiller in the 1830s. 6.0 POWER TO MAIM AND KILL The vegetable kingdom offers an enormous range of poisons. These poisons may be present in the flower, seed, leaf, stem, or root. Their quantity varies according to the time of the y~ar, the time of the day, the soil, and the weather. A dawn killer may be impotent by noon, and a poor s~il can restri?t the amount of poisonous glycosides or alkaloids present In the plant. Plant products or their derivatives are important ~o everyday life, whether in an urban. or rural. area In economically developed countries, or. In the third w~rld, because they directly affect our well-being, In the~e. V~rlOU~ environments are found hundreds of plants that are inJUriOUSIf ingested, and are capable of causing any number of symptoms, including death. 29 •• Many houseplants are poisonous and children are attracted III the colourful parts of these otherwise harmless organism 11 our midst. Few realise, for example, that apple seeds cont 11" cyanide, which may be lethal in large doses; that the eatin ClI green and sprouting parts of potatoes may cause sev I1 poisoning and that common houseplants such as oleand r , caladiums, dieffenbachias and philodendrons must IJI avoided, for a person ingesting the leaves of oleander, or it sweet nectar, may develop severe vomiting, irrequln: heartbeat, and respiratory paralysis, followed by death. Htly fever and dermatitis result from an abnormality of our irnrnunr system known as allergy. The abundant grasses, treo , shrubs, weeds, and fungi in our environment produce pollen, spores, and other materials to which we become sensitised that on re-exposure they cause discomforting symptoms th t may become life-threatening. Certain plants have the disturbing quality of modifying our cell in other ways. Some give rise to mutations that may occur in our reproductive cells, permanently altering succeeding generations if these cells are utilised in reproduction. Others may affect our somatic or body cells in a way that causes congenital abnormalities, resulting in irreparable damage to the foetus. Even more insidious, some plants have the ability to induce cellular aberrations, especially in the peripheral blood, perhaps affecting the immune and clotting systems, and in some instances causing death. Plant proteins, typified by those found in the juice of the pokeweed, enter the body through simple cuts and abrasions to do their damage. Plants have also developed an array of weapons, like thorns, stinging hairs, irritating leaf surfaces, and a lethal chemical arsenal (secondary metabolites), to ward off herbivores while remaining firmly rooted. Plants are also 'poisonous' to one another - a phenomenon known as allelopathy - essentially a form of chemical warfare between different species of plants. For instance, the walnut tree is not planted in gardens because a chemical known as jug lone leaches from the roots and leaves and will inhibit the growth of many common garden 30 1'1 HIt especially tomatoes. Some plants arm themselves with 1"11 ons or prickles as a deterrent and defence. Others live by 1111119 and overtly lure their prey by means of bright colours HHI tantalising smells. These are the plant carnivores, and HI mal flesh is a necessary part of their diet. Their techniques 1 1I1CJO from mechanically operated springs and traps to a more I1 I ive enticement into a cup of poison. Their victims are 1110 tly insects, which, once caught, are marinated in digestive ulds and absorbed into the plant's channels. But there are I 01 cs where such a small fry is left struggling on its gummy 10 thold as bait for bigger victims such as frogs and lizards. I here are hundreds of carnivorous plant species growing in w rm and temperate parts of the world, mainly in bog land where the soil's nitrogen supply needs supplementing. These plants are armed with the glutinous mechanism of springs, tubes, and suckers, strangling their improvident prey. I xamples include Utricularia adpressa, Drosera aberrans, Orosophyl/um lusitanicum, Nepenthes adnata, Philcoxia bahiensis, Roridula dentata, Triphyophyl/um peltatam. 6.1 Major Poisonous Principles Found among Plants The major poisonous principles found among plants are organic compounds, such as alkaloids, diterpenes, cardiac and cyanogenic glycosides, nitro-containing compounds, oxalates, resins and certain proteins and/or amino acids. Some plants also accumulate inorganic elements, largely from the soil, and these too may have serious effects on animals and/or man. 31 Table 10: Major Types of Alkaloids Classified by Basic Ring Structure with Examples of Poisonous (and Other) Plants Containing Each (Lewis & Elvin-Lewis, 1977) Plant Alkaloid Type Major Family I Genus and I Vernacular NameAlkaloid Species Alkaloids with heteroc ciic nitrogen atoms Pyridine- Coniine APIACEAE Conium Poison hemlock piperidine maculatum - Arecoline ARECACEAE Areca catechu Betel nut palm - Lobeline CAMPANULACEAE Lobelia inffata Indian tobacco - Piperine PIPERACEAE Piper nigrum Pepper - lsopelletierine PUNICACEAE Punica Pomegranate granatum - Nicotine SOLANACEAE Nicotiana spp., Tobacco Duboisia - Hopwoodii - Tropane Ecgonine ERYTHROXYLACEAE Erythroxylum Cocaine (cocaine) coca -Atropine, SOLANACEAE Atropa Belladonna hyoscyamine belladonna -Scopolamine Datura Jimson weed stramonium -Duboisia spp. ~ Hyoscyamus Henbane niger ~ Mandragora Mandrake officinarum - Tropine Withania somnifera ~ Isoquinoline Berberine BERBERIDACEAE Mahonja Oregon grape aquifolium Tubocurarine MENISPERMACEAE Chondodendron Curare component tomentosum Morphine, PAPAVERACEAE Papaver Opium poppy codeine somniferum ~ noscapine (narcotine), papaverine, thebaine ~ Berberine, Argemone Prickly poppy sanguinarine mexicana -'Berberine, Chelidonium Celandine sanguinarine, majus chelidonine 32 Aporphine Corydalis Fitweed caseana, Dicentra spp. Dutchman's breeches -Sanguinarine Sanguinaria Bloodroot canadensis ---y-Hydrastine RANUNCULACEAE Hydrastis Goldenseal canadensis Emetine RUBIACEAE Cephaelis Ipecac ipecacuanha 1-Quinoline Viridicatin FUNGUS Penicillium viridicatum ~---Acronycine RUTACEAE Acranychiabau eri Quinine, RUBIACEAE Cinchona and quinidine Remijiaspp -~Indole Ergonovine, FUNGUS C/av;cepspurpu Ergot ergotamine rea -Psilocybin FUNGUS Psilocybe spp. -Vinblastine, APOCYNACEAE Catharanthus Periwinkle vincristine raseus Reserpine Rauvolfia - serpentina -Physostigmine FABACEAE Physostigma Calabar bean venenosum Gelsemine, LOGANIACEAE Gelsemium Yellow jassamine sempervirine sempervirens Strychnine, Strychnosnux - Strychnine brucine vomica Imidazole Pilocarpine RUTACEAE Pilocarpus .- jaborandi ~Pyrrolizidine Retrorsine ASTERACEAE Senecio spp. Groundsel BORAGINACEAE Echium Viper's bug loss - plantagineum -Heliotrine, Heliotrapium Heliotrope lasiocarpine europeaum -Monocrotaline, FABACEAE Cratalaria Rattlebox retrorsine spectabilis Pyrrolizidine Retrorsine ASTERACEAE Senecio spp. Groundsel - Heliotrine, BORAGINACEAE Echium Viper's bugloss - lasiocarpine plantagineum ~ Heliotropium Heliotrope europaeum --Quinolizidine Sparteine FABACEAE Cytisus Scotch broom scoparius -Cytisine Labumum Golden-chain anagyroides Lupinine Lupinus SOD. Lupine 33 Steroid Cevadine LlLICEAE Schoenocaulon alkaloids offlcinalis Ester Veratrum viride American h lie h'" alkaloisgermidine & germitrine, glycoalkaloid veratrosine Zygacine Zigadenus spp. Death camas Aconitine RANUNCULACEAE Aconitum spp. Aconite Solanidine SOLANACEAE Lycopersicon Tomato esculentum Solanidine Solanum spp. Purine Caffeine AQUIFOLlACEAE ffex paraguariensis Mate bases Caffeine RUBIACEAE Coffea arabica Coffee Caffeine SAPINDACEAE Pauffinia cupana Guarana Caffeine STERCULIACEAE Colanitida Kola Caffeine THEACEAE Camellia sinensis Tea Theobromine STERCULIACEAE Theobroma cacao Chocolate Alkaloids without Heterocyclic Nitrogen Atoms Alkaloids Ephedrine EPHEDRACEAE Ephedra sinica amines Mescaline CACTACEAE Lophophora Peyote williamsii Cathine CELASTRACEAE Catha edulis Chat 6.2 Cyanogenic Glycosides The glycosides yielding hydrocyanic acid (HeN) as on product of hydrolysis are called cyanogenic. Probably the most widely distributed of these is amygdalin which is commonly found in the Rosaceae (rose family). Amygdalin is found in large quantities in seeds of apples and pears and in the stony seeds, bark and leaves of apricots, bitter almonds, wild and domestic cherries, peaches, and plums. In the hydrolysis of amygdalin, a two-step process (Fig. 2), two molecules of glucose are released, the first caused by the enzyme amygdalase, the second by prunase. Free hydrocyanic acid is the violently toxic end product of the hydrolysis. The severity of poisoning from cyanide in plants depends on how much free HeN and/or cyanogenic glycoside exists in the plant. Hydrocyanic acid inhibits the action of the enzyme cytochrome oxidase, the terminal respiratory catalyst linking atmospheric oxygen with metabolic respiration. Therefore, 34 11< IN poisoning is asphyxiation at the cellular level. As little as () () g has caused death in man, and the largest dose from wluch a person has been known to recover is 0.15g. A wide range of plants possess cyanogenic glycosides ( , pable of releasing HeN. Selected examples of su.ch plants Ire presented in Table 11, which shows a predoml~ance of IJ nera classified in the Rosaceae. This presentation also Illustrates the great number found in the allied Fabaceae (pea r mily), as well as in the totally unrelated Poaceae (gra~s family). Some of the common poisonous. plants f~und In Nigeria are shown in Table 12 together With the poisonous part, common and vernacular names. ~-C6HIP5 OftIygdolal'~ O~H · C6HI206 CN MA~lONlme GLUCOSIDE OH Io-iH CN MANDElONITRllE Figure 2: Hydrolysis of Amygdalin H I0(=0P'~lt ~ + HeN IHydroqonic Acill aEH2AlDEH't'OE 35 Table 11: Some Important Toxic Plants Having Cyanogen t Glycosides Arranged Phylogenetically Angiosperms: Dicotyledons CHENOPODIACEAE. Suckleya PASSIFLORACEAE. Adenie. Passif/ora EUPHORBIACEAE. Maniho!. S!i//ingia ROSACEAE. Cercocarpus, Cotoneaster, Eriobotrya. Malus. Prunus, Pyrus. Rhodotypos FABACEAE. Acacia, Cassia, Dotichos. Lotus, Phaseolus. Trifolium Vicia SAXIFRAGACEAE. Hydrangea . MYRTACEAE. Eucalyptus L1NACEAE. Unum OLACACEAE.Ximenia CAPRIFOLlACEAE. Sambucus BIGNONIACEAE. Crescentia ASTERACEAE. Ageratum, Bahia. Florestina Angiosperms: Monocotyledons JUNCAGINACEAE. Trig/ochin POACEAE. Cynodon. Glyceria, Holcus, Panicum. Sorghum, Zea Table 12" Some of the Common Poisono PI t " N"us an Sin Igena Botanical Name & Family Poisonous Common Vernacular Part Name Name 1. Abrus orecatorius (Fabaceae) Seed, leaf Rosarv oea Oiu ologbo 2. Nicotiana tabacum (Solanaceae) Leaf Tobacco Taba; Aasa 3. Nerium oleander (Apocynaceae) Leaf. seed Oleander; Upeelila roselaurel 4. Ricinus communis (Euphorbiaceae) Seed Castor oil Eweka; Larun bean 5. Calotropis procera (Apocynaceae) Leaf Giant milk Bomubomu weed 6. Anacardium occidentale Seed Cashew Kaju (Anacardiaceae) 7. Funtumia elastica (Apocynaceae) Latex Lagos silk Ako Ire rubber 8. Adenopus breviflorus Fruit Wild melon Itagiri (Cucurbitaceae) 9. Jatropha curcas (Euphorbiaceae) Leaf Physic nut Lapalapa 10. Prosopis africana (Fabaceae) Seed Iron wood Avan 11. Lantana camara (Verbenaceae) Leaf Spanish flaQ Ewon-acoco 12. Solanum dasyphyllum Root Egg plant Boboawodi (Solanaceae) 13. Bambusa vuloaris (Poaceae) Leaf Bamboo Opaarun 14. Antiaris toxicana (Moraceae) Saollatex Poison arrow Iqi ora 15. Argemone mexicana Fruit, leaf Prickly poppy Mafowokan (Paoaveraceae) 16. Chrysophyllum albidum Unripe fruit Cherry Agbalumo (Saootaceae) 17. Senna hirsuta (Fabaceae) Leaf Hairy senna Asunwon 36 18. Erythrophleum suaveolens All parts Sasswood Epo obo (Fabaceae) 19. Plumbago zeylanica Root, leaf Wild leadwort Inabiri (Plumbaqinaceae) 20. Capsicum annum (Solanaceae) Root Chilli/sweet Atarodo pepper 21. Urlica dioica (Urlicaceae) Leaf Stinging nettle Esinsin 22. Uraria picta(Fabaceae) Leaf Dubra Aluparada 23. Ceiba pentandra(Bombacaceae) Stem Kapok tree Egunqun 24. Sc/eria depressa(Cyperaceae) Fruit Sword grass Labelabe 25. Croton Seed, leaf Turk's carp Aworoso penduliflorus(Euphorbiaceae) 26. Euphorbia unispina Sap Cactus Ora adete (Euphorbiaceae) 27. Cucumis melo (Cucurbitaceae) Fruit, sap Musk melon Baara-ekute 28. Entada qioas(Fabaceae) Leaf, fruit Monkey ladder Ewe aaoba 29. Manihot uti/issima (Euphorbiaceae) Tuber, leaf Cassava Ege pupa 30. Physostigma venenosum Bark,seed Calabar bean Epo obe (Fabaceae) 31. Cannabis saliva (Cannabaceae) Leaf Marijuana, Igbo; Ako-taba weed Source: Olowokude]o 2010 Description of Some Poisonous Plants Ricinus communis L.(Euphorbiaceae) Castor oil plant An annual herb or a short - lived perennial about 1 - 8meters high. The stem is green or reddish brown becoming hollow with age, with prominent leaf scars and well marked nodes. Leaves are palmate 4 - 12 partite for about half the length. The fruit is a globose capsule usually spiny with an elongated 3 - lobbed pedicel. Seeds are ovoid, compressed dorsally, shinning, pale grey to almost black with a yellowish-white caruncle at the base. The shiny seeds have very beautiful and intricate designs. Like human faces or finger prints, no two seeds have exactly the same pattern, and they exhibit infinite genetic variation. These seeds are among the most deadly seeds on earth, and it is their irresistible appearance that makes them so dangerous. 37 Figure 3: Castor Oil Plant (Ricinus communis): Foliage and Seeds The seed~ are poisonous to people, animals and insects. One of. t~e main tOXICproteins is "ricin" - a potent cytotoxin. One ml~lIgr~m of ricin can kill an adult; symptoms of human pOlsonl.ng beqin within a few hours of ingestion and these are: abdominal pain, vomiting, di~rrhoea, sometimes bloody; and thereafter, - severe dehydration, a decrease in urine and low blood pressure and death. Castor Seeds and the Assassination of a Journalist at a Bus Stop Near Waterloo Station in London In 1978, th.e toxic protein (ricin) of the castor oil seed was used to assasslnat~ Georgi Markov, a Bulgarian journalist who s~oke out ~galnst the Bulgarian Government. He was stabbed with the point of an umbrella while waiting at a bus stop near Waterloo Statio~ in London. The autopsy revealed a p~rforated metallic pellet that contained the ricin embedded in his leg. Medicinal Uses of Castor Oil Plant Ironically, t~is plant possesses a wide variety of medicinal uses: t~e 011 from the seed is a well-known laxative that has been Widely used for over 2,000 years! It is considered to be fast, safe and gentle, prompting a bowel movement in 3 - 5 hours f?r. both the young and the aged. The seed is anthelmintic, cathartic, emollient, laxative, and purgative. It is rubbed o~ the temple to treat a headache and is also powered and applied to abscesses and various skin infections. The leaves are used as a poultice to relieve headaches and treat 38 boils. Castor seeds are pressed to extract castor oil which is used for medicinal and other commercial purposes. Ricin does not partition into the oil because it is water-soluble, therefore, castor oil does not contain ricin, provided that no cross-contamination occurred during its production. In the United States, castor oil has been used by the military in aircraft lubricants, hydraulic fluids, and in the manufacture of explosives. It is now of importance in a wide variety of technical applications due to its unique content of ricinoleic acid. The oil is used, for instance, in the manufacture of some lubricants, plastics, surfactants, paints and dyes and in the preparation of imitation leather. Textile scientists have used sulphonated (or sulfated) castor oil in the dyeing and finishing of fabrics and leather. It has also been used in the synthesis of soaps, linoleum, printer's ink, nylon, varnishes, enamels, and electrical insulations. It is also found in many commercial skin care products. When it is used in the manufacture of soap, it forms a clean, light-coloured soap with a stable lather, which dries and hardens well. It is used for hair conditioners, treating conditions such as dry or brittle, damaged hair or hair loss (as a very thick oil with a slight but prominent odour and slightly sticky texture). It is also often used as an emollient and skin softener, and being free from smell, and has been recommended for medicinal use as a treatment of gastrointestinal problems, lacerations and other skin disorders such as psoriasis. 7.0 POWER TO CURE, NOURISH AND SUSTAIN Plants that possess therapeutic properties or exert beneficial pharmacological effects on the human body are generally designated as medicinal plants. Medicinal plants naturally synthesise and accumulate secondary metabolites like alkaloids, steroids, terpenes, flavonoids, saponins, glycosides, cyanogens, tannins, resins, lactones, quinines, volatile oils etc. Medicinal plants have been used for the treatment of illnesses and diseases since the dawn of time. Ancient Chinese scriptures and Egyptian papyrus hieroglyphics described medicinal uses of plants. Indigenous 39 cultures of Africa and Native Americans used herbs in th It healing rituals, while others developed traditional rnedicul systems (e.g. Ayurvedic and Traditional Chinese Medicine) 111 which herbal therapies were used. Researchers have found that people in different parts of the world tend to use the sam or similar plants for treating the same illnesses. Medicinal plants are of immense value for primary healthcar and income generation for a wide segment of the world' population, most especially in developing countries. World Health Organisation (WHO) consultative group defined medicinal plant as 'any plant which, in one or more of it organs, contains substances that can be used for therapeutic purpose or which are precursors for the synthesis of useful drugs'. Sofowora (1982) elaborated on this definition to includo the following: (a) plants or plant parts used medicinally in galenical preparations (e.g. decoctions, infusions, etc); (b) plants used for extraction of pure substances either for direct medicinal use or for the plant hemi - synthesis of medicinal compounds (e.g. hemi-synthesis of sex hormones from diosgenin); (c) food, spice, and perfumery plants used medicinally; (d) microscopic plants, e.g. fungi, actinomycetes, used for isolation of drugs, especially antibiotics; (e) fibre plants, e.g. cotton, flax, jute, used for the preparation of surgical dressings. The plant kingdom represents a vast emporium of untapped medical potentialities and this has led to a resurgence of interest in ethnomedicine, ethnobotany, and ethnopharmacology (Olowokudejo, 1987; Fadeyi et al., 1989; Olowokudejo, 1993, 2008). Nigeria's vast landscape, variable climate and rich geographical features endowed her with some of the most diverse plant groups in Africa. The wide variety of medicinal plants has been an important part of the health care system in Nigeria since the ancient time (Olowokudejo et al. 1993). The heavy reliance on plant medicine is attributed to their efficacy, relative accessibility, low prices, local availability, and general acceptance by local communities and the 40 11 dequacy of health centres and doctors for health care 11 eds, especially in rural areas (Olowokudejo & 8amgbowu, 1993). 7.1 Global Use and Value of Medicinal Plants The World Health Organisation (WHO, 1978) estimated that 70-80% of the population in the developing countries depend on herbal traditional medicine as their primary health care (Olowokudejo, 1987; Olowokudejo & Pereira - Shetolu, 1988). Farnsworth &Soejartor (1991) and Srivastava (2001) have observed that the above applies to many people worldwide. With the realisation that it would be impossible to replace herbal medicine with western techniques in the foreseeable future, the WHO established a Division on Traditional Medicine and has been leading a revival of interest in medicinal plants. Ever since the global demand for herbal medicine is not only large but growing (Srivastava, 2000). The market for Ayurvedic medicines is estimated to be expanding at the rate of 20% annually in India (Subrat, 2002), while the quantity of medicinal plants obtained from just one province of China (Yunnan) has grown ten times in the last ten years (Pei Shengji, 2002).· An example of increased pressure on collecting grounds is provided by the Gori Valley in the Indian Himalayas where the annual period of Medicinal and Aromatic Plants (MAP) harvesting has increased from two to five months (Uniyal et al., 2002). Contributory factors of the growth in demand for traditional medicine include the increasing human population and the glaring inadequate provision of Western (allopathic) medicine in developing countries as shown for some African countries in Table 13. 41 :: ../':~ Table 13: Ratios of Doctors (Practicing Western Medicine) and Traditional Medical Practitioners (TMPs, Practicing Largely Plant-based Medicine) in East and Southern Africa Marshall, 1998) Country Doctor: Patient TMP: Patient Ehiooia 1:33,000 - Kenya 1:7142 (overall) - Malawi 1:833 (urban - 1:987 (urban - Mathare) Mathare) 1:50,000 1:138 Mozambiaue 1:50,000 1:200 South Africa 1:1639 (overall) - 1:17,400 (home and 1:700 -1200 (Venda) areas) Swaziland 1:10,000 1:100 Tanzania 1:33,000 1:350 - 450 (Dar es Salaam) UQanda 1:25,000 1:708 Herbal medicine is becoming ever more fashionable in richer countries, a market sector which has grown at 10-20% annually in Europe and North America over recent years (ten Kate & Laird, 1999). In addition, there are many related botanical products sold as health foods, food supplements, herbal teas, and for various other purposes related to health and personal care. The extent to which herbal preparations are prescribed within conventional medicine varies greatly between countries, for instance being much higher in Germany than in the UK or USA (Hamilton, 2003). Plants have contributed hugely to western medicine, through the provision of ingredients for drugs or having played central roles in drug discovery (Bringmann et al., 1997). Some drugs, having botanical origins, are still extracted directly from plants, others are made through the transformation of chemicals found within them, while yet others are today synthesised from inorganic materials, but have their historical origins in research into the active compounds found in plants. There are undoubtedly many more secrets still hidden in the world of plants (Ayensu, 1978; Olowokudejo & Nyananyo, 1990; Olowokudejo & Pereira-Sheteolu, 1992; Mendelssohn & Balick, 1995). 42 7.2 The Value of Ethno Medicine In terms of the number of species individually targeted, the use of plants as medicines represents by far the biggest h~man use of the natural world. Plants provide the predomlna~t ingredients of medicines in most medical trad.iti.ons. There IS no reliable figure for the total number of medicinal plants on Earth and numbers and percentages for countries and regions vary greatly (Schippmann et al., 2002). Estimates for the numbers of species used medicinally include: 35,000 - 70,000 or 53 000 worldwide (Farnsworth &Soejarto, 1991; Schipp~ann et al., 2002); 10,000 - 11,250 in China (H~ & G~, 1997; Pei Shengji, 200; Xiao & Yong, 1998); 7500 In India (Shiva, 1996); 2237 in Mexico (Toledo, 1995); and 2572 traditionally by North American Indians (Moerman, 1998). T~e great majority of species of medicinal plants are used on.IY In Folk Medicine. Traditional Medical Systems employ relatively few: 500-600 commonly in Traditional Chinese Medicine. (?ut 6000 overall) (Pei Shengji, 2001); 1430 in Mongolian. ~edlcln~ (Pei Shengji, 2002b); 1106-3600 in Tibetan M~dlclne (Pel Shengji, 2001; Pei Shengji, 2002b); 1250-1400 In Ayurveda (Oev, 1999); 342 in Unani; and 328 in Siddha (Shiva, 1996). Plants have always been a rich source of lead compou~ds, e.g. morphine, cocaine, digitalis and quinine, tubocurarine, nicotine and muscarine. Many of these lead compounds are useful drugs in themselves, e.g. morphine a~d quinine an.d others have provided the basis for the production ~f synthetic drugs (e.g. local anaesthetics developed from cocaine). There is recognition that plants are promising sourc~s of new drugs. Over 120 pharmaceutical products currently In use are plant- derived and at least 75% of these were discovered. by examining the use of these plants in tradition.al madlcine. Table 14 shows a list of clinically useful drugs derived from the tropical rainforest (Ayoola, 2008). 43 Table 14: Some Clinically Useful Drugs from the Tropical Rainforest Drua Plant Source - Seecles & Familv Theraceutic Category Ajmalicine Catharanthus roseus Circulatory stlmulan; (Aoocynaceael A~:ihY:ler:ensive Andrographolide Andrographis paniculata An:ibac:erial (Acan:naceae) kecoline Areca catechu A'l:ihelmin~"ic, Alzheimer's disease Asiaticoside Centella asiatic (Umbelliferae) Vulnerary A:rooine Atropa belladonna (Solanaceae) A'lticholinerQic Bromelain Annanas comosus A'l:i-infiamma:ory IBromeliaceaellPineaoolel Camphor Cinnamonuun camphora Rubefacien: (Lauraceae - Camohor tree) Chrvmooaoian CaricaoaDava(Caricaceae) Proteolytic; Mucolvtic Cocaine Erythroxy/um coca Local anaestheflc (Erv•hroxvtaceae-Coca) Curcumin Curcuma longa L. (Zing:beraceae - Choleretic, an"oxidant Turmeric) Deserp'dme Rauwolfia tetraphylla L. Antihyper:ensive, Tranquiliser (Aoocvnaceae) L-Dooa Mucuna deerinoiana ILeauminosael A'l:ioarkinsonism Emetne Cephaelis Ipecacuanha (Rubiaceae Amoebicde. Eme:'c -/oecae) Glaucarubm Simarouba glauca (Simarcuoaceae- Amceolc'de Pa-adse tree) Glaziovine Ocolea glaziovii Mez (l.auraceae- An:idepressant vellow cinnamon) I Gossvool I Gossvnlum SPD, (Malvaceae' Male corrraceotive Hvocvamine Hvoscvamus nioer [Solanaceae) I A'l::chol:nerQ:c Kawaina Pltet metnvsicum. (Pioe'll.:eae: _.-J Tra'lQu;liser Moncrotaline I Crotalaria spectabilis I A'l:itumour agent (:ooical) ILeauminasae) Mornhine Peoeve: somniferum Analceslc Neaandrographolide Andrographic paniculata Dysen~'Y IAcanthaceae i Nicotine Nicotiana tabacum IScla'13ceael Insedcide Ouabain Stroohanthus gratus (A:lOcvnaceael Cardio:onic Paoain Carica Dapaya (Caricaeae-Paoava) Prc!eoly-jc, Mucoly'jc Physostigmine Physostigma venenosum Anticholines:erase fLeauminasael Picrotoxin Anamirta cocculuc (Fish berrvl Analeo:ic Pilocarpine Pilocarpus jaborandi (Rutaceae) Parasympa:nomimetic (Jaborandi) Quinidine Cinchona ledgerian (Rubiaceae- A'ltiarrhy'.hmic Yellow cinchonal Quinine I Cinchona legeriana (Rubiaceae- A'ltimalarial, Antipyretic Yellow cinchonal Quisoualic acid Quisoualis indica, (Combretaceae) A~tihelmin:hic Rescinnami Rauwolfia serpentinalAoocvnaoeael T ranauiliser Resernine Rauwolfia serpentinalvomitoria Tranauiliser 44 (Apocvnaceael Roriferone Rorippa indica (Cruciferael Antitussive Ra:enone Lonchocarpus nicou (Leguminosae- Pesticide Cube rootl Scooolamine Datura metel(Solanaceae I Travel sickness S:evioside Stevia rebandiana Hemsley Sweetner (Comoosi:eae) S~'Ychnine Strychnos nuz-vomica CNS stimulant (Loqaniaoeae) Theobromine Theobroma cacao (Cocoa, cacao) Diuretic; Vasodilator Tubocurarine Chondrodendron tomentosum Skeletal muscle (Menisoermaceael Curare Vasicine Adhatoda vasica (Acanthaceae) Oxy:ocic (PeQaninel Vinblastine, Catharanthus roseus Antitumour agents Vincris:ine, (Apocynaceae~adagascan Vinorelbine periwinkle) Yohimbine Pausinvstalia vohimba (Rubiaoeael Adrenemic blocker, aphrodisiac Source: Ayoola, 2008 The number of plant species that provide ingredients for drugs used in Western Medicine is even fewer. It was calculated for an article published in 1991 that there were 121 drugs in current use in the USA derived from plants, with 95 species acting as sources (more than one drug is obtained from some species) (Farnsworth & Soejarto, 1991)_ Despite the small number of source species, drugs derived from plants are of immense importance in terms of number of patients treated. It is reported that ea. 25% of all prescriptions dispensed from community pharmacies in the USA between 1959 and 1973 contained one or more ingredients derived from higher plants (Farnsworth & Soejarto, 1991). A more recent study, of the top 150 proprietary drugs used in the USA in 1993, found that 57% of all prescriptions contained at least one major active compound currently or once derived from (or patterned after) compounds which are derived from plant diversity (Grifo & Resenthal, 1997). Table 15: Number and Percentages of Medicinal Plant Species Recorded for Different Countries and Regions The sizes of the floras (Column 3) are from Centres of Plant Diversity (WWF & IUCN, 1994 - 1997), except for the world estimate (bottom row) which is based on an estimate that 45 270,000 ~ 425,000 species of vascular plants are alrcr dy known, with a further 10 - 20% to be discovered (Govacrtl 2001). I Country Number of Total Number % of References to or Species of of Native Flora Figure in Region Medicinal Species in which is Column 2 Plants Flora Medicinal China 11,146 27,100 41 I (Pei Shengji, 2002a) India 7,500 17,000 44 (Shiva, 1996) Mexico 2,237 30,000 7 (Toledo, 1995) North 2,572 20,000 13 (Moerman, 1998) America World 52,885 297,000- 10-18 (Schippmann et 510,000 al.,2002) The value of medicinal plants to human livelihoods is essentially infinite. They obviously make fundamental contributions to human health. Financially, the retail sales of pharmaceutical products were estimated at US$ 80 - 90 billion globally in 1997, with medicinal plants contributing very significantly (Sheldon, et ai, 1997). A study of the 25 best- selling pharmaceutical drugs in 1997 found that 11 of them (42%) were either biological, natural products or entities derived from natural products, with a total value of US$ 17.5 billion (Laid & Kate, 2002). The total sales value of drugs (such as Taxol) derived from just one plant species (Taxus baccata) was US$2.3 billion in 2000 (Laid & ten Kate, 2002). The world market for herbal remedies in 1999 was calculated to be worth US$ 19.4 billion, with Europe in the lead (US$ 6.7 billion), followed by Asia (US$ 5.1 billion), North America (US$ 1.4 billion) (Land & Pierce, 2002). Although virtually everyone on Earth benefits from medicinal plants, it is the financially poorest who are typically most closely dependent on medicinal plants - culturally and for their medicines and income (Olowokudejo, 1990, 1992, 2012). Only 15% of pharmaceutical drugs are consumed in developing countries (Toledo, 1995), and a large proportion of even this small percentage is taken by relatively more affluent people. The poor have little alternative to using herbal medicine, 46 which, anyway, they may prefer - at least for certain «onoitions (Marshall, 1998). Both rural and urban dwellers, in d veloping countries, rely on medicinal plants, many rural p ople still depending largely on plants collected from close to their homes, while town folks depend, for the most part, on dried plants transported in from rural areas. Medicinal plants provide a significant source of income for rural people in developing countries, especially through the sale of wild-harvested material. The collectors are often herders, shepherds or other economically marginalised sections of the population, such as landless people and women. Between 50 - 100% of households in the northern part of Central Nepal and about 25 - 50% in the middle part of the same region are involved in collecting medicinal plants for sale, the materials being traded on to wholesale markets in Delhi (Olsen, 1997). The money received represents 15 - 30% of the total income of poorer household (Hamilton, 2003). 7.3 Plants Sustain National Economy and Provide Nourishment Value of Forest Products (Wood) There are several uses of the forest, but the use generating the largest direct economic revenue is the harvest of wood, i.e. timber logs for sawn wood and wood products, small dimensions for fuelwood and several other uses (World Bank, 1995). The forest wood products are (i) Sawn logs (ii) Transmission poles (iii) Building poles (iv) Fuelwood (v) Bamboo (iv) Chewing sticks. These products are sold in bundles in various rural and urban markets. Value added to these products comes from (a) Splitting the fuelwood into small bundles, (b) Converting logs into the sawn wood, (c) Producing the chewing sticks from logs, (d) Substituting other building materials with poles, bamboo and raffia roofing. The. forest production is a source of input to several economic sectors. Shortage of forest products can have severe economic impacts on traditional economies or when processing sectors lack a raw material and must use more expensive substitutes such as imported goods. 47 Some of the timber species which are well - known, us d locally and also exported in reasonable quantities are listed 111 Table 16 with their trade names. Some of these species ar found in some major timber markets in the country but are no longer as abundant as they were two decades ago. The well known species are becoming scarce. Table 16: Timber Species and Their Trade Names in Nigeria Trade/Common Name Botanical Name Obeche Triplochiton sc/eroxylon Abura Mitragyna stipulosa Abura Mitragyna ciliata Apa Afzelia africana Apa Afzelia bipindensis Ana Afzelia oecnvtobe Mansonia Mansonia altissima Lagos mahogany Khaya ivorensis Benin mahogany Khaya grandifoliola Dry zone mahogany Khaya senegalensis African walnut Lovoa trichilioides Iroko Milicia excelsa Ceiba (Silk cotton) Ceiba pentandra Gedu Entandrophragma angolense Afara Terminalia superba Opebe Nauclea diderrichi Antiaris Antiaris africana Omu Entandroohragma candollei Utile Entandrophragma utile Ekki Lophira alata Ogea Daniella ogea Ebony Diospyros crassiflora Bombax Bombax buonopozense Omo Cordia o/atvthvra Source: Olowokudejo,2008 Non-Wood Forest Products Non-wood forest products (NWFPs) play a crucial role in supporting community welfare as significant sources of edible product, fodder, fuel, fertiliser (mulch), fibres, medicines, gums and resins, oil and construction materials. Millions of people around the country living in rural areas in the vicinity of forests subsist on these products. They help to provide opportunities for additional employment and income. Activities related to the 48 collection and primary processing of NWFPs lend themselves suitable for equitable participation of women and indigenous people. While some of the NWFPs have entered a national and international trade, they tend to have a comparative advantage in supporting the development of rural and backward areas. At the national level, NWFP production and use, both in the informal and formal sectors, involve large numbers of people in harvesting, collecting, processing, marketing and in some cases even exporting. The informal nature of NWFP - transactions often result in the rural producers not receiving an equitable share of the benefits/profits, especially in situations where exploitative trade relationships exist. NWFPs and Household Food Security NWFPs are important in household food security because they supplement household agricultural production as shown in Table 17. The varied products are particularly important in reducing the shortage suffered during the period of scarcity of the agricultural cycle. They also help to even out seasonal fluctuations in the availability of food. NWFPs often contribute essential inputs for household nutrition. They are also valued as components of social and cultural identity. Riverine communities in the coastal regions, most especially the Niger Delta zone, derive the majority of their income from three NWFPs in the freshwater swamp forests zone. The products include (i) Raphia spp. (gin and larvae), (ii) Calamus spp. (Swamp cane), (iii) Irvingiagabonensis (Ogbono) (Powell, 1994). The importance of NWFPs is similarly high in villages around Cross River National Park (Infield in Drolet, 1991), Kainji Lake, Okomu and Gashaka - Gumpti National Parks. 49 Table 17: General Contributions of Forest Food to Human Nutrition Type of Forest Food Nutrients Fruits and berries Carbohydrates (fructose & Soluble sugars), vitamins (especially C), minerals (calcium, magnesium, potassium); some provide protein, fat or starch. Nuts Oils and carbohydrates Young leaves, herbaceous Vitamins (beta-carotene, C) calcium, plants iron Gums and saps Proteins and minerals .. . ..Source. Food and Nutrition Division, FAO (1994) Apart from meeting the subsistence needs, the potential of NWFPs for poverty alleviation is particularly important. The weight of poverty falls heavily on certain groups among whom are tribal communities who depend on biodiversity products for employment and income derived through collection and processing of a range of NWFPs. Millions of rural workers process NWFPs at home or in local shopfloors to earn the incomes which enable them to survive. 8.0 CULTURAL AND SPIRITUAL POWER OF PLANTS The power of plants over human life and well-being is not just practical, physical and utilitarian, but also cultural and spiritual. The diversity of the natural world has been a constant source of inspiration throughout human history, influencing traditions and the way our society has evolved. Cultural, amenity and spiritual services provided by ecosystems are highly valued by the poor, and play a key role in the medium to long-term Sustainable Development Strategies. Indeed, cultural diversity itself has been affected by the distribution of biodiversity. Cultural ecosystem service generally depends on the importance of particular cultural relationships with various features of the landscape, such as particular stands of forests, and with specific components of biodiversity, such as particular revered species. The vast majority of formal religions and belief systems have clear links with the natural world (Ash 50 and Jenkins, 2007). Human beings instinctively derive aesthetic and spiritual satisfaction from biodiversity. Many people derive value from biodiversity through leisure activities such as enjoying a walk in the countryside or natural history programmes on television. Biodiversity has inspired musicians, painters, sculptors, writers and other artists. Many cultural groups view themselves as an integral part of the natural world and show respect for other living organisms. It has always been known that our emotional well-being is enhanced by the proximity of natural beauty. The strong bond between humanity and biodiversity is reflected in the art, religions and traditions of diverse human cultures. This might have been the reason for the worshipping of nature as gods and goddess as mentioned in some ancient mythologies. In ancient times, the man had been known to worship the sun, the moon, the sky, the rivers, the land, some trees, e.g. lroko (Milicia excelsa), Araba (Ceiba pentandra) and Ose (Adansonia digitata); in South-western Nigeria). Some of these cultural practices have endured in many traditional societies in Nigeria till today. In general, human cultures coevolved with their environment, and therefore the conservation of biological diversity can also be important for cultural identity. The natural environment provides many inspirational, aesthetic, spiritual and educational needs of people from all cultures both now and in the future. The aesthetic values of our natural ecosystems and landscapes contribute to the emotional and spiritual well-being of a highly urbanised population. The cultural, spiritual and religious significance of biodiversity can be further demonstrated by the diverse values attached to some species of plants. The calabash, known botanically as Lagenaria siceraria (Cucurbitaceae), is a flowering plant fruit which occurs in various shapes and sizes. Calabashes have been used as ritual vessels as far back as the 9th century A.D. in Igbo - Ukwu in South-eastern Nigeria (Layiwola, 2008). Apart from their popular function as utilitarian objects in food production, they also function as musical instruments e.g. as rattles, drums, resonators and maracas. Calabashes are also used as media of passing on symbolic messages that are 51 coded but understood within a particular culture and cont I They are also easily transformed into beautiful decoratlv •• objects. The hard but smooth surface of the calabash is ,I medium through which Artists further explore form and textur They are also used in many professions such as farming, fishing and wine-tapping among others. One of the mo I popular cultural festivals in Nigeria, The Argungu Fishin festival in Kebbi State is hinged on the calabash. In Northern Nigeria and the northern fringes of Edo State, young women and girls usually display beautifully decorated calabashes during cultural festivals. Calabashes were also used as a means of expressing African philosophical thoughts. For instance, when a king was to be dethroned he was not told verbally to desert the throne of his forefathers. Such messages were couched in metaphoric language to ease the pain of abdication. In Oyo kingdom, South-western Nigeria, a white calabash was sent to the king who would have to abdicate the throne soon after receiving it (Layiwola, 2008). In Igbo culture (South-eastern Nigeria) the calabash was used as a means of severing links between the spirit and the living world. When a man dies, the cup-shaped calabash which he uses to drink palm wine in his lifetime would be broken at the last stage of his burial rites. This act signifies that he has transcended from earth to the spirit world and disengaged from the gatherings of village elders. The calabash cup personified the owner and it was forbidden for anyone to drink from another person's cup at any time. Moreover, one of the most established uses of calabashes in African Traditional Religion is their use as vessels for conveying sacrifices to the gods during ancestral worship. In traditional African societies, trees and forests played and still play significant roles in settlement patterns and group identity. For instance, many communities, public spaces, bus stops and landmarks are named after dominant tree species located in that vicinity as shown in Table 18. 52 , hlo 18: Communities, Public Spaces and Bus Stops NamedS .after Plant pecres Botanical FamilyIN Vernacular I Plant Species Common Name Bombacaceae1. Idi Araba Ceiba pentandra Meliaceae2. Idi Iroko Milicia excelsa Irvingiaceae3. Idi Oro lrvinaie gabonensis Artocarpus communis Moraceae4. Breadfruit Fabaceae5. Idi Awin Dialium auineese Adansonia digitata Bombacaceae6. Idi Ose Cordia millenii Boraginaceae7. Idi Omo Idi Emi Butyrospermum Sapotaceae8. paradoxum FabaceaeAlbizia zvaie9. Idi Ayunre Eclipta prostrata Asteraceae10. Idi Aape Symphonia globulifera Guttiferae11. Idi Aba SapindaceaeIdi Isin Bliahia seokie12. SyzYaium auineense Myrtaceae13. Idi Ori Brachysteaia eurycoma Fabaceae14. OkeAko Forested hill Manv families15. Oke labo Elaeis guineensis/ Palmae16. Palm grove Rovstonee soo. Idi Odan Ficus thonningii Moraceae17. Idi Agbon Cocos nucifera Palmae18. Elaeis guineensis Palmae19. Idi Ope Anacardiaceae20. Idi Mongoro Mangifera indica Idi Arere Triplochiton scleroxylon Sterculiaceae21 Source: Olowokude]o, 2010 According to the Catholic Encyclopae?ia, about 130 tla~tsh some of which have medicinal properties ~nd m?st 0 w. IC are native to Egypt and Palestine are mentlone.d In th~ Bible. Examples of symbolic usage of plants in the scriptures Include the following: • Lilies of the field - refers to God's generosity and benevolence (Matthew 6:28); (C/ethra arborea) ". Olive tree - symbolises fruitfulness, ble~slng and happiness, the emblem of peace and prosperity as well as fertility (Romans 11: 17 - 24); (Olea europaea). Mustard seed - depicts the unimaginable greatn~ss of the Kingdom of God (Mark 4: 30 - 32, Matthew 13. 31 - 32)' (Brassica juncea). . . . All 'flesh is grass - indicates the Similarity and seasonality of all life forms (Isaiah 40: 6). • • • 53 Withering grass and fading flowers - symbolise th transience of life (Isaiah 40: 7 & 8); (Family Poaceae). Branches of palm trees - signify victory and triumph (John 12: 13). (Elaeis guineensis). Thorns and thistles - symbolise sin and its consequences (Genesis 3: 17-18). The fir tree, the pine tree - represent beauty, glory and virtue (Isaiah 60: 13) (Pinus spp.). Vine - symbolises the relationship between God and humanity (John15:1) (Cissus quadrangularis). The wormwood - typifies bitterness, sorrow and suffering (Jeremiah 9: 13-15). In the Authorised King James Version of the Holy Bible, Book of Genesis, Chapter two, copious references are made to GARDEN and PLANTS: Verse 8 says, "And the LORD God planted a garden eastward in Eden; and there he put the man whom he had formed'. Verse 9 states: And out of the ground made the LORD God to grow every tree that is pleasant to the sight, and good for food; the tree otlite also in the midst of the garden, and the tree of knowledge of good and evil. Verse 15: And the LORD God took the man, and put him into the garden of Eden to dress it and to keep it. Verse 16: And the LORD God commanded the man, saying, Of every tree of the garden thou mayest freely eat: Verse 17: But of the tree of the knowledge of good and evil, thou shalt not eat of it: for in the day that thou eatest thereof thou shall surely die." These revelations are quite instructive regarding the gardens full of trees and how humans should relate to them. • • • • • • In traditional societies, the palm frond is also used to demarcate disputed land areas or plots of land that must not be trespassed. The sacredness of shrines is also publicised by adorning them with palm fronds while it indicates the presence of a corpse in a vehicle. In Yorubaland, the leaves of the evergreen tree, Akoko (Newbouldia laevis) is an integral component of chieftaincy title conferment rituals. 54 .0 PLANTS AS STIMULI OF EXPLORATION AND CIVILISATION lants have had a profound influence on man's economic, cultural, and political history. Civilisation would have been impossible without the tilling of land and the deliberate sowing or planting of crop plants- what we now refer to as Agriculture. Before agriculture, people and their ancestors depended for food upon their activities as gatherers and hunters. In ancient preagricultural days, carelessness may sometimes have caused some of the collected grain from the wild grasses to be scattered around the habitation site, where it then germinated. It is likely that the ground near such a place of abode was particularly ric