Medicinal Plants (Bot 203) PDF

MEDICINAL PLANTS (BOT 203) Historical background of medicinal plants (Divine) The current state of health care gives us significant clues. The price of health care in every country in the world is rising and getting out of the reach of billions of people. Effective drugs are not only getting more...

MEDICINAL PLANTS (BOT 203) Historical background of medicinal plants (Divine) The current state of health care gives us significant clues. The price of health care in every country in the world is rising and getting out of the reach of billions of people. Effective drugs are not only getting more expensive to develop and dispense, they are also becoming harder to discover. This is because the diseases are becoming more virulent and more resistant to the common treatments that remain within the reach of most people. Health services, where available, are burdened by the shortage of skilled specialists and practitioners. Pharmaceutical companies on one hand are into desperate searches for the next big drug treatments while they are under pressure to sell their current lines of products at lower prices for the benefit of most people, especially in the less developed nations where basic health care is extremely difficult to come by, let alone afford. Meanwhile, the drugs that seem to be more affordable and easier to obtain are the most counterfeited. It appears good health care is only for the rich. So what about the less privileged people? There are all manners of political and economic discourse about how to address these issues. The real tragedy in all this is that we still do not turn to God for the answers. What is He telling us? If we do ask, then He will clearly show us that he has already provided the solutions for us and that they are in our backyards, gardens and farms. He is God who knows all things and he has given all the plants for our foods and healings (Genesis 1:29). All he wants is for us to ask that our eyes be opened to see the miracles. He has already placed around us (Exodus 15:23-26). When he opens our eyes we will see that he has given us plants for medicinal use in two major ways; as curative and preventive to help sustain our minds and bodies. Medicinal plants as curative in scriptures 1 Their fruits will be food and their leaves for medicine (Ezikiel 47:12). In 2 King 20:1-12, the story is told of King Hezekiah, King of Judah who became so ill after developing a sore which on God’s judgment was to take his life. In anguish, Hezekiah prayed for mercy and forgiveness. In response, God sent Isiah to Hezekiah who told him to make poultice of figs (Ficus carica), a fruit common in the Middle East even today and a staple of their diet, to put on the boil. When this was done, Hezekiah returned to full health. Today, this goes on of course. A simple example is quinine, an extract from a tree that grows in the tropics which has been widely used in the treatment of malaria. What is significant here is that the cure was found in a tree that grew in the very place where the disease was predominant. Even with the quinine resistant strains of malaria parasites, plants like Artemisinin have been discovered. According to the Catholic Encyclopedia, some 130 plants are mentioned in the scriptures and most of these plants are native to Egypt and Palestine. Some plants mentioned in the Bible and their medicinal properties 1. Hyssops (Hyssops officinalis) which was used for ritual cleansing and purification (Lev. 14:4, Psalm51:7) has been proven to have mild germ killing properties and is said to help heal wound and bruises. Hyssops tea is also known to have been used to treat fever, cold, indigestion and asthma in historical times. Others include; 2. Balm of Gilead (Amyris gileadensis) for healing, 3. Minth (mentha species) used for flavouring food because of their fresh aroma and sweet taste, 2  4. Rose emits soft balsamic aroma and has insect repellant properties (Songs of Solomon), 5. Lavender (Lavendula anguistiofolia), a herb with fragrant essential oil. It is very expensive and Egyptian used for mummification and perfume. Bible account has it that Mary used it to anoint the feet Jesus and thereafter wiped his feet with her hair (John 12:3). 6. Aloe (Aquilaria) as perfume, 7. Apple fruit (Malus communis) for reviving a fainting person according to catholic encyclopedia, 8. Sweet cane (Calamus) yield perfume, 9. Cedarus libani used for ceremony of purification, 10.Galbanum (Ferula galbaniflua) is among the spices mentioned in which the Lord commanded Moses to burn as incense before the tubercle of meeting (Exodus 30:24). Its odour is said to be pungent and might have been used to drive insects from the sanctuary, 11.Hemlock (conium maculatum) known to contain poison, 12.Mandrake (Mandragora offincinarum) (Genesis 30:14) also known as love plant and belied to ensure conception. 13.Myrrh (Bilsamondendron myrrha) an aromatic plant used as perfume (Exodus 30:23) and in embalming as applied to the body of Christ (John 19:39-40). 14.Terebinth (Pistacia terebinthus), the turpentine tree (Isaiah 6:13) produces a pleasant smelling oil which is used in the East to flavor wine and sweet meats. Plants in the Qur’an Shajarah (tree) 1. The first mention of plants in the Qur’an is in connection with the event of Adam and his wife, who having been heralded into garden, were instructed 3  thus; “O Adam! Dwell you and your wife in the garden and eat of the beautiful things therein as you will; but approach not this tree (Q 2:35)” Different interpretations that trail the real meaning of this tree are not relevant in this context. It is obvious that shajarah (a plant) is mentioned, parts of which are recommended as meal while other parts are prohibited. The recommended ones must have been found good for the body. 2. Yaqtin: And we curse a plant of gourd to grow over him (Q37:146). According to Ibn Qayyim, the yaqtin mentioned in the Quran is the pumpkin which is also called Dubba Qar etc. Ibn Qayyim described the medicinal value of Yaqtin as being useful for those who suffer from phlegm or cold condition. The wetness contained in it helps ease the thirst and headache by drinking its extract or washing one’s head with it. It is also beneficial to those in the hot temperatures. 3. Jidh’i Nakhlah (Date palm): the medicinal value of this tree is described in practical terms in the Qur’an (19:22-26). When Maryam, the mother Prophet (AS) was pregnant, she found her way to the wilderness and seated leaning on a palm tree. She was soon possessed by the pain of child birth and she cried out soliciting a divine intervention, which come to her instantly and instructively: “shake the trunk of the palm tree under which you were seated and eat of the date that drop” (Q19:22-26). She carried out the instruction and safely delivered her baby. It must be noted that Mary was not instructed to chant an incantation or a litany but to eat a date from the palm tree. Researches can still be conducted into both the date and the palm to identify the medicinal properties contained in them which are capable, among other things, of facilitating easy and safe childbirth. Nakhlah is mentioned in several other parts of Qur’an such as (Q50:68, Q6:141, Q16:67) etc in all, the fruit is associated with health care. It may be of interest to research into other uses of date. 4 4. Zaytun (Olive tree): the olive tree is described in the Qur’an 24:35 as a blessed tree. The Quranic description indicates that olive is not a localized plant but a very common one in different parts of the World. Medically, for example, its oil fortifies the stomach as it also counteracts the effects of vapours. The oil is also useful at religious ceremonies such as anointing with it, for it keeps off Satan (Suyuti, 1996). 5. Sidr (Lote tree): sidr is mentioned four times in the Qur’an (Q34:16, Q53:14, Q53:16, Q56:28). According to Yusuf Ali, sidr is wild, shrubby, thorny and useless plant. In cultivation, it bears fruit and some shade and can be thorn less, thus becoming a symbol of heavenly bliss. Ibn Qayyim (1996) states that Nabq is the fruit produced by the Lote tree, which soothes the natural digestive organs, helps against diarrhea, coats the stomach. As Suyuti (1996) recommend sidr for ashing the head to cure or prevent scurf. 6. Rumman (pomegrannates): the plant with its fruit as mentioned in the Qur’an (55:68) is capable of curing coughs and preventing stomach upsets especially if taken after meals. 7. Baql (pot herbs), Qiththa (Cucumbers), fum (garlic), Adas (lentils), and Basal (onions) (Q2:61). They are mentioned as food items, which obviously have medicinal values in view of traditional function of food in the body. 8. Tin (figs): tin plant mentioned in Q (95:1), is good for a chronic cough. It is also efficacious for opening up the alimentary tract. According to Ibn Qayyim (1996), the best type of figs are the white kind when they are ripe as they clear the sand that accumulates in the liver and prostate, serve as a preventive substance against poison and provide nourishment for the body. 9. Athl (tamarisk): mentioned in Qur’an 34:16. It is an astringent for the stomach and a haemostatic. 5  10.Thamarat (fruits/flowers): Qur’an 16:68-69 narrates the process of honey production as bees are divinely guided to obtain relevant ingredients from different plants. The bees thus issue drink (honey) of varying colors and uses out of their bodies. The honey as established by modern medical sciences has the medicinal value to cure injury, stomach upset, eye disease etc. The Alludes to the fact that the bees are divinely guided to certain plants to obtain properties for honey making. Historical background of medicinal plants (Human research) - The earliest type of medicine in all countries is use of plants (Herbalism). - The earliest written account of herbal remedies comes from china and dates back to 2,500 BC. In 2,735 BC, the Chinese emperor Shen Nong recommended the use of Ma Huang (Ephedra) in the western world, for instance against respiratory distress. Ephedrine isolated from ephedra is widely used as decongestant. Around 400 BC, Hippocrates, A Greek, referred to as the father of medicine developed principle of diet, exercise and happiness as the cornerstone of health and his book Materia medica which consist of herbal recipes of compilation of about 400 simple remedies was published. Theophrastus, another famous Greek (biologist- botanist) produced Historia plantarum which became the standard botanical text book in his time and for years after his death. Discorides in 60 AD, produced De Materia medica which was regarded as the standard reference work in Europe because it contained the description of about 600 medicinal plants (Le strange, 1997). The search continued by the Arabian physicians who after translating the works of the Greeks into Arabic, added their own drugs and observations. 6 The entire Middle East has a rich history of herbal healing. There are texts surviving from the ancient cultures of Mesopotamia, Egypt and India that describe and illustrate the use of many medicinal plants and products, including castor oil, linseed oil and white poppies. Egyptian hieroglyphics show physicians of the first and second centuries A.D. treating constipation with senna pods, and using caraway and pepper mint to relieve digestive upsets. In the south west of Nigeria, Orunmila is the first person who practiced the art of healing with plants. His knowledge was said to be divine inspiration. Some earliest literatures apart from the unpublished works are a list of plants in native medicine in Nigeria (Ainsilie, 1937), the African family physician (Adigbulaja, 1946). And medicinal plants in Nigeria (Oliver, 1956), the useful plants of west tropical Africa (Dalziel, 1956) among others. WHO reports that between 40% - 60% of the world’s population presently use herbal medicine for some aspect of primary health care. Medical practice using plants include Ayurvedic, homeopathic, naturopathic, traditional oriental and Native American Indian medicine. WHO notes that of 119 plant derived pharmaceutical medicines, about 74% are used in modern medicine in ways that correlated directly with their traditional uses as plant medicines by native cultures. The importance of traditional medicine as a source of primary health care was first officially recognized by the WHO in the primary health care declaration of Alma Ata (1978) and has been globally addressed since 1976 by the traditional medicine programme of the WHO. The programme defined traditional medicine as: the sum total of all the knowledge and practices, whether explicable or not used in diagnosis, prevention and 7  elimination of physical, mental or social in balance and relying exclusively on practical experience and observation handed down from generation to generation, whether verbally or in writing. Challenges Facing Traditional Medicine 1. Lack of official government recognition of traditional medicine and their practitioners. 2. Inadequate allocation of resources for development and capacity building. 3. Lack of scientific proof of efficacies of many remedies. 4. Problem of ensuring proper use medicaments and difficulties in protecting traditional medicine practitioners, knowledge. Recommended ways of addressing these challenges according to who, 2002. 1. National policies and legal frame work: these are needed in order to define the role of traditional medicine in traditional health care delivery system and how it can contribute to the health care reform. The policies should therefore cover a range of issues, including: legislation and regulation for herbal products and practice of therapies; education, training and licensing of providers; research and development; and allocation of financial and other resources. The policy should include the protection of intellectual property right of traditional Med. Practitioner. 2. There is the need for adequate and improved quality of research methodology for evaluating traditional medicine also; research in safety and efficacy should be promoted. 3. Countries should ensure the quality, efficacy and safety trad. Med that goes to their citizens. There should be national regulation and registration of 8  herbal medicines; safety monitoring of herbal medicines; support of clinical research into the use of traditional medicine and production of national pharmacopoica and monographs of medicinal plants. 4. There should be promotion of rational use of traditional medicine by providers and consumers. Adequate information, education and communication strategies would assist in overcoming some of the misconception allopathic practitioners have about traditional medicine and it could raise awareness of its potential benefits. 5. Ensure conservation of plants. IDENTIFICATION, COLLECTION AND PREPARATION OF MEDICINAL PLANTS Identification of Medicinal Plants Make sure that you know exactly which plant to use to treat a problem. The names of plants vary from one place to another. Different plant species may have the same local name. The botanical name of each plant used in this manual is given with each remedy, except for the most common plants. Here are some things to check to make sure you use the right plant. Type of plant Approximate size of the plant. Type: tree, woody, shrub, vine, grass. The position of flower or fruit in the plant (such as on the ton of stem in the branches). Leaves 9 Approximate size Shape (number of leaflets or lobes, with ridges or not) and colour. Texture (smooth or rough, with hair or not). Position and arrangement Leaves Flowers Type of flower; type of inflorescence. Size, colour and shape of flowers and bud. Flowers Fruits Approximate size. Shape, colour when young or ripe. Seed present or not. Size, shape and colour of seeds. 10  Fruits Bark Present or not. Colour and texture (smooth or rough). Collection of Medicinal Plants Know which plant materials to collect and what time to collect them. The content of the active ingredient may depend on the plant part, stage of growth, season of harvest, method of handling during collection, physical condition of its collection place and storage. Leaves and stems are best collected during daytime and when the plant is about to bloom. Flowers that have a smell are best collected when the flower buds are just about to open and in the morning when the sun is still low. Other flowers should be collected when they are in full bloom. Sometimes, collection should be done in batches since flowers do not bloom at the same time. 11 Unless the recipe says that unripe fruits will be used, fruits should be collected when they are ripe. Fleshy fruits which deteriorate rapidly should be gathered when they are somewhat ripe, preferably in the early morning or at nightfall. Seeds are usually collected from thoroughly ripened fruits. Some dry-textured fruits fall off the plant or split open easily when fully ripened. As a result, seeds are easily scattered and lost. It is advisable to collect such fruits as soon as they start ripening. Barks should be collected when the plants are in bloom or in vigorous growth. Barks should be collected from the trunk and branches. Roots and other underground parts (e.g., rhizome, rootstock, stem tuber, bulb and stolon) are best collected when the plant is in full growth. Avoid indiscriminate collection Avoid collecting plants in a way that kills the plant or damages its surroundings. Before collecting any, determine first how much of the plant and what parts are needed to prevent wastage. Collect only the plant parts you need. For instance, if you need only the leaves, take only the leaves and only the number that you need. Medicinal plants should be conserved to ensure their continuous supply. After collection Sorting and cleaning Clean plant parts of soil and dust. 12 Plants that may have been exposed to pesticides should not be used. If you have no other choice, they should be washed properly in clean water. Clean and wash plants as quickly as possible to avoid damaging them. Drying Air-drying is the best way of drying herbal plants. Drying at high temperatures will destroy plant ingredients. Spread the plant materials thinly and evenly over an old newspaper, a bamboo mat, or chicken-wire screen. Put in the shade until the materials are dry. Drying can be done through artificial heat, especially in the rainy season. Heating devices vary from one place to another. Cutting, trimming, grinding, chopping These are done for various reasons: To increase the efficacy of the plants materials. To allow more active ingredients to go into the preparation. To reduce the toxicity or adverse effects of certain drugs. To shorten the duration of drying. To make the plant material more convenient to store. Storing Medicinal plants should be properly stored to preserve their quality. Otherwise, they may be attacked by insects, mites and fungus. Storage can also ensure the continuous supply and availability of the materials whenever they are needed. Dried plants should be kept in covered plastic containers or bottles. These should be covered tightly and kept in a cool, dry place away from sunlight. Label the container properly 13 with the name of the plant and the date when it was collected. Do not use any stored herbal plant which has molds or is discolored. Preparing Herbal Medicine Plant materials can be either fresh or dry, depending on the need and preparation. If dried plants are to be used as a substitute for fresh parts, adjust the quantity or the weight since water is lost during drying. Decoction Boil the plant parts in water, preferably for 15-20 minutes from the time the water has started boiling. Some healers recommend boiling the plant materials until the original volume of the water is reduced to one half. Some plants are soaked or moistened. Ideally, plant materials should be decocted twice in order to extract their active ingredients thoroughly. Strain or filter the liquid either while it is still hot or after cooling. Decoction Infusion Pour hot or cold water onto the fresh or dry plant material and allow it to stand. Cover the preparation tightly to stop important ingredients from being lost. The 14 length of time needed to prepare an infusion depends on the type of plant material and whether the water is hot or cold. In general, hot infusions need to stand for only 5-15 minutes; cold infusions may require up to 24 hours. Filter the preparation (and allow hot liquid to cool) before administering to the sick. Infusion Powder Pound and grind the dried plant materials into coarse, intermediate or fine particle sizes. Sift the powder (once or several times) through coarse or fine sieves to get the required particle size. Powder Juice 15 Pound the fresh plant materials, then pass them through a cheesecloth or any fine piece of cloth in order to get the juice. Or you may just squeeze the plant parts to extract the juice. Juice Poultice or paste A poultice is a moist, semisolid preparation which is applied directly on the skin. Prepare it by grinding the plant materials (either fresh or dry), sometimes with a little oil, water, molasses, honey, or other liquids. Poultice or paste Bolus 16 A bolus is made by pounding fresh or dried plant material' and adding sufficient binding agent such as honey or molasses. Roll it or shape it with your hand to make a round or oval ball Bolus Gathering of Ethnomedicinal information Gathering information about a medicinal plants used traditionally for treating an ailment requires ethnomedicinal/ethnobotanical survey. The survey involves visits to traditional medical practitioners, herbalists, herb sellers and some other persons who have knowledge in medicinal plants, and indeed the therapeutic uses using a semi structured questionnaire. The interview need to be carried out in local languages with the questionnaire as a guide, using a tape recorder and/ or camera where applicable. In order to bridge the gap normally posed by language barrier, interpreters were incorporated where such barrier was encountered. The questionnaire need to encompass the ailment for which the plant is used, part of the plant that is used to effect treatment, method and solvent of preparation, mode and route of administration, dosage regimen, name of collector, place of collection, date/season of collection, identity of the plant etc. 17 Classification of Medicinal Plants on the Basis of Life Forms There is a large number of medicinal and aromatic plants in the nature which are used for medicinal and aromatic purposes. Moreover, medicinal plants are sometimes used for aromatic purposes similarly aromatic plants may also be used for medicinal purpose! Hence, classification of medicinal and aromatic plants is difficult. Since there is a large number of plants in these two groups an attempt has been made here to facilitate for further study. Classification of Medicinal Plants Medicinal plants are generally classified on the basis of their growth habit. It may be either a tree, shrub, herb, annuals, biennial, tubers, rhizomes or climbers. Classification based on therapeutic properties (of plants found in Nigeria) 1. Analgesic plants S/ Common Botanical Name Therapeutic uses Parts No names used 1 2 3 4 5 2. Expectorant plants 1 2 3 18 4 5 3. Antimalarial plants 1 2 3 4 5 6 4. Anticancer plants 1 2 3 5. Antihypertensive plants 1 2 3 4 5 6 7 6. Antidiabetic plants 1 2 3 19  4 7. Antihyperlipidaemic plants 1 2 3 4 5 Transformation of the crude drugs from medicinal plant into conventional drugs 1. Extraction of active components from plant materials followed by pharmacological evaluation. 2. Partitioning of the extract using solvents of various properties followed by pharmacological evaluation. 3. Isolation of phytochemical compounds followed by pharmacological evaluation. 4. Toxicological evaluation 5. Clinical trial of the pharmacologically active agents 6. Characterization of phytochemical compounds. Best solvents for extraction Polar solvent – water, alcohol (e.g methanol, ethanol) Intermediate polar solvent – acetone, dichloromethane, Non polar solvent – n-hexane, ether, chloroform 20 Active ingredients in plants. They are phytochemicals which possess therapeutic or pharmacologic properties and are considered as medicine or drugs. These include alkaloids, anthocyanins, anthraquinone, bitters, cardiac glycosides, cyanogenic glycosides, coumarines, flavonoids. These are also called secondary metabolites. Methods of Phytochemical analysis Separation and separating techniques. Chromatographic techniques such as thin layer chromatography, high performance-liquid chromatography, gas chromatography mass- spectroscopy, liquid chromatograph-mass spectroscopy and non-chromatographic techniques such as immunoassay as well as monoclonal antibodies, phytochemical screening assay, flourier transform mass spectroscopy are used to obtain pure compounds. Good luck By Dr Isah Audu Otaru 21