Ethnobotanical Leaflets 12: 373-387. 2008.

 

Origins of Plant Derived Medicines

M. Maridass* and A. John De Britto

Animal Health Research Unit & Plant Molecular biology Research Unit

St.Xavier’s College (Autonomous)

Palayamkottai-627002

Email: orchideyadass@yahoo.com

 

Issued 11 June 2008

 

Abstract

This review article describes the origins of plant derived medicines that have been developed as a result of traditional knowledge being handed down from one generation to the next. Various industries are now searching into sources of alternative, more natural and environmentally friendly antimicrobials, antibiotics, diabetics, antioxidants and crop protection agents. Medicinal plants have provided a good source of a wide variety of compounds, such as phenolic compounds, nitrogen compounds, vitamins, terpenoids and some other secondary metabolites, which are rich in valuable bioactivities, e.g., antioxidant, anti-inflammatory, antitumor, antimutagenic, anti-carcinogenic, antibacterial, or antiviral activities. Medicinal plants have become the main object of chemists, biochemist, and pharmaceutics. Their research plays an important role for discovering and developing new drugs that hopefully have more effectiveness and no side actions like most modern drugs.

 

Origin of Medicine

Fossil records revealed that the human use of plants as traditional medicine date back to middle Paleolithic age, approximately 60,000 years ago (Solecki et al., 1975). The plants were used as flavors, foods, insect deterrents, ornamentals, fumigants, spices, and cosmetics (Kunin et al., 1996; Pieroni et al., 2004). Generally, the medicinally useful plants are sold as commodities in the market, and those that are sold for medicinal purposes dominate the market (Runner et al., 2001). At present, natural products (and their derivatives and analogs) represent over 50% of all drugs in clinical use, in which natural products derived from higher plants represent ca. 25% of the total (Alandrin et al., 1998). The World Health Organization estimated that over 80% of the people in developing countries rely on traditional remedies such as herbs for their daily needs (Tripathi et al., 2003), and about 855 traditional medicines include used crude plant extracts.  This means that about 3.5 to 4 billion of the global population rely on plants resources for drugs (Farnsworth, 1988).

               Many infectious diseases are known to be treated with herbal remedies throughout the history of mankind.  The maximum therapeutic and minimum side effects of herbal remedies have demonstrated or verified in numerous scientific investigations.  Even today, plant materials continue to play a major role in primary health care as therapeutic remedies in many developing countries (Czygan, 1993; Ody, 1993). 

Market Demands of Medicinal Plants

Nearly 95 percentage of plants used in traditional medicines are collected from forests and other natural sources. The plants collected from different sources show wide disparity in therapeutic values and also much variation in market rates. In the recent years there has been greater expansion of indigenous drug industry in India. Consequently the demand for the new material (medicinal plants) has enormously increased. According to latest estimate, there are about eight thousand licensed pharmacies of ISM in the country, engaged in the manufacture of bulk drugs to meet the requirement of people. The total annual requirement of the raw materials of these pharmacies was estimated to be thousands of quintals. This is presently met by cutting trees in the forest or uprooting herbs and shrubs either on nominal payment or unauthorized. Further, there is prime need to provide authentic or genuine drugs to manufacture standard medicine, as emphasized by earlier worker (Singh and Ghouse, 1993). The annual demand of the global market is $32 million of medicinal plants from developing countries. The herbal drug production in our country has been estimated to be rupees 4000 crores in the year 2000. Out of 15,000 - 20,000 medicinal plants, our rural communities use 7,000 - 7,500 medicinal plants. About 130 pure compounds, which are extracted from 100 species of higher plants of Indian origin, are used throughout the world. India can play a major role for supplying the raw herbs, standardized extracted materials and pure compounds isolated from natural resources (Mitra, 2002).

New medicines have been discovered with traditional, empirical and molecular approaches (Harvey, 1999). The traditional approach makes use of material that has been found by trial and error over many years in different cultures and systems of medicine (Cotton, 1996).

Table 1. Currently used Drugs in the United States that are obtained from flowering Plants.

 

Plant Name

Family

Used Drugs

Ammi majus

Umbelliferae

Xanthotoxina

Ananas comosus

Bromeliaceae

Bromelain

Atropa belladonna

Solanaceae

Belladonna Extract

Avena sativa

Gramineae

Oatmeal Concentrate

Capsicum species

Solanaceae

Capsicum Oleoresin

Carica papaya

Caricaceae

Papain

Cassia acutifolia

Leguminosae

Sennosides A + B

Cassia angustifolia

Leguminosae

Sennosides A + B

Catharanthus roseus

Apocynaceae

Leurocristine (vincristine)

Vincaleukoblastine (vinblastine)

Cinchona species

Rubiaceae

Quinine

Citrus limon

Rutaceae

Pectin

Colchicum autumnale

Liliacae

Colchicine

Digitalis lanata

Scrophulariaceae

Digoxin,Lanatoside C,

Acetyligitoxin

Digitalis purpurea

Scrophulariaceae

Digitoxin

Digitalis whole leaf

Dioscorea species

Dioscoreaceae

Diosgenin

Duboisia myoporoides

Solanaceae

Atropine,Hyoscyamine

Scopolamine

Ephedra sinica

Ephedraceae

Ephedrine, Pseudoephedrine

Glycine max

Leguminosae

Sitosterols

Papaver somniferum

Papaveraceae

Opium,Codeine,Morphine

Noscapine, Papaverine

Physostigma venenosum

Leguminosae

Physostigmine (Eserine)

Pilocarpus jaborandi

Rutaceae

Pilocarpine

Plantago species

Plantaginaceae

Psyllium husks

Podophyllum peltatum

Berberidaceae

Podophyllin

Prunus domestica

Rosaceae

Prune Concentrate

Rauvolfia serpentine

Apocynaceae

Reserpine,Alseroxylon Fraction

Powdered whole root Rauwolfia

Rauvolfia vomitoria

Apocynaceae

Deserpidine, Reserpine

Rescinnamine

Rhamnus purshiana

Rhamnacee

Casanthranol

Rheum species

Polygonaceae

Rhubarb Root

Ricinus communis

Euphorbiaceae

Castor Oil, Ricinoleic Acid

Veratrum viride

Liliaceae

Veratrum viride  Cryptennamine

 

 Natural products have provided many effective drugs. These include  a wide range of older drugs such as quinine (Kremsner et al., 1994) and morphine (Benyhe et al., 1994) and newer drugs such as paclitaxel (TaxolTM) (Wani et al., 1971), camptothecin (Wall et al., 1966), etoposide (Endo et al., 1976), mevastatin (Keller-Juslén, et al., 1971), and artemisinin (Klayman, 1985). Further evidence of the importance of natural products is provided by the fact that almost half of the world’s 25 best selling pharmaceuticals in 1991 were either natural product or their derivatives (O’Neill, 1993).

 

 

 

The number of higher plant species (angiosperms and gymnosperms) on planet earth is estimated around 250,000 (Ayensu et al., 1978), with a lower level at 215,000 (Cronquist, 1981) and an upper level high as 500,000 (Tippo et al., 1977; Schultes, 1972). Of these, only about 6% have been screened for biological activity, and only 15% have been pharmacologically screened. Moreover, plant extracts contain up to several thousands of secondary metabolites. The major types of compounds identified in Indian medicinal herbs include alkaloids, saponin, flavonoids, anthroquinones, terpenoids, coumarins, lignans, polysaccharides, polypeptides and proteins. Efficient detection and rapid characterization of these components on a molecular basis offer better understanding of the pharmacological application of Indian herbal medicines. 

Plant-Derived Drugs from Traditional Systems of Medicine

For thousands of years, plant-derived (herbal) remedies have remained a vital part of traditional Chinese medicine, and even today it constitute about a 30% to 50% proportion of the total drug therapy for a fifth of the world’s population who live in the People’s Republic of China (PRC). Out of 5500 medicinal plants used in traditional Chinese medicine, between 300 and 500 are commonly used in regular prescriptions (Han et al., 1988). A drug that has been in use in China for at least 5000 years is Ephedra sinica (Ma huang), from which the potent sympathomimetic amine ephedrine was isolated and pharmacologically tested in the early years of this century, and is now used in western medicine in the form of various salts to combat bronchial asthma (Tyler et al., 1988). Recently phytochemical investigation on plants used in Chinese traditional medicine, both in the PRC and elsewhere, have led to the discovery of several hundred pharmacologically active substances, and about 60 new drugs being derived from such compounds. (Xiao and Fu, 1987).

   The drugs commonly used in People’s Republic of China PRC include tropane alkaloids anisodamine and anisodine from Scopolia tangutica, which are employed as a mild, naturally acting anticholinergic agent for septic shock in cases of bacillary dysentery, and in the treatment of migrane headache. An isoquinoline alkaloid, racemic tetrahydropalmatine, from Corydalis ambigua is used as an analgesic and tranquilizer, and indirubrin, a nitrogen-containing metabolite produced by Indigofera tinctoria, is effective in the treatment of chronic myelocytic leukemia (Xiao and Fu, 1987; Han et al., 1988).

 

Plant-Derived Antibacterial Chemotherapeutants

Infectious disease is the number one cause of death accounting for approximately one-half of all deaths in tropical countries. Death from infectious diseases, ranked 5th in 1981, has become the 3rd leading cause of death in 1992, with an increase of 58% (Pinner et al., 1996).

More than hundreds of plants world wide are used in traditional medicine as treatments for bacterial infection (Martin et al., 2003). Although many have been treated by conventional pharmaceutical approaches, there is a growing interest in the use of natural products by the general public. In addition the pharmaceutical industry continues to examine their potential as sources novel growth factor, immunomodulatory and antimicrobial activity (Ghose et al., 2003).

Plant-Derived Wound Healing Agents

Wound healing occupies an important field of research in modern biomedical sciences. Wound healing involves cellular, physiological, biochemical and molecular processes which result ultimately in connective tissue repair and the formation of a fibrous scar (Peacock, 1988). Wound healing process uses a combination of three mechanisms. Contraction is the major method by which wound healing occurs at an amputation site, such as the tip of a finger. Epithelisation predominates in the healing of abrasions and connective tissue deposition occurs when lacerations are sutured and closed (Cockbill et al., 2000).

Healing of wound is an important part of the reparative process. A detailed pathophysiology of wound was better understood following the establishment of the theory of a cell signal cascade system involved in the formation of new tissues repairing the wound. Like the alchemist’s dream of turning base metal into gold, efforts aimed at achieving a perfect wound healing has inspired many researchers in trying various therapeutic options which were thought to aid or accelerate the wound healing process. The cheaper and more effective the agent, may be better for the patient. Durodola (1977) demonstrated the effectiveness of crude extract of Ageratum conyzoides in inhibiting the growth of Staphylococcus aureus, a major wound pathogen in in-vitro cultures of the organism. Much work has recently been done on the wound healing effect of several medicinal plants (Oladejo et al., 2003; Biswas et al., 2003; Abo et al., 2004; Biswas et al., 2004).

 

Plant-Derived Anti-Diarrhoeal Agents

               Diarrhoea is a major health problem especially for children under the age of 5 years and up to 17% of all death in the indoor pediatric patients is related to diarrhoea.  Worldwide incidence of diarrhoeal death account for more than 5-8 million each year in infants and small children less than 5 year especially in developing countries (Fauci et al., 1998).  According to WHO estimate for the year 1998, there were about 7.1 million deaths due to diarrhoea (Park et al., 2000). A range of medicinal plants with anti-diarrhoeal properties has been widely used by the traditional healers; however, the effectiveness of many of these anti-diarrhoeal traditional medicines have not been scientifically evaluated (Chitme et al., 2004).

 

Plant-Derived Anti-Diabetic Agents

   There are 143 million people worldwide suffering from diabetes, almost five times more than the estimates ten years ago. This number may probably double by the year 2030. Therefore, the global human population appears to be in the midst of an epidemic of diabetes. Reports from the World Health Organization (WHO) indicate that diabetes mellitus is one of the major killers of our time, with people in Southeast Asia and Western Pacific being most at risk.

               Diabetes mellitus is a metabolic disorder characterized by hyperglycemia. It may be secondary to a deficiency or disturbance in the secretion of insulin or to an abnormal response of peripheral tissues to insulin. The resulting metabolic derangement of the intermediary metabolism of carbohydrate, lipid, and protein affects all organ systems but most prominent in the arteries, arterioles, and capillaries (Damjanov et al., 1996). There are two main categories of this disease. Type 1 diabetes mellitus also called insulin-dependent diabetes mellitus (IDDM) and Type 2, the non-insulin-dependent diabetes mellitus (NIDDM). IDDM represents a heterogenous and polygenic disorder, with a number of non-HLA loci (about 20) contributing to the disease susceptibility. Though this form of diabetes accounts for 5 to 10% of all cases, the incidence is rapidly increasing in specific regions.  It is estimated that incidence of Type 1 diabetes will be about 40% higher in the year 2010 than in 1997, and yet there is no identified agent substantially capable of preventing this type of disease. NIDDM is far more common and results from a combination of defects in insulin secretion and action. This type of disease accounts for 90 to 95% of all diabetic patients. Treatment of type 2 diabetes is complicated by several factors inherent to the disease process, typically, insulin resistance, hyperinsulinemia, impaired insulin secretion, and reduced insulin-mediated glucose uptake and utilization (Tiwari and Madhusudana Rao, 2002).

The recommended use of plants in the treatment for diabetes needs to be evaluated. Plants are important not only for the control of type 2DM but also for its prevention, especially for people with elevated levels of blood glucose and blood intolerance who have a greater risk of developing diabetes (Anderson et al., 2004). Botanical products can improve glucose metabolism and the overall condition of individuals with diabetes not only by hypoglycemic effects but also by improving lipid metabolism, antioxidant status, and capillary function (Bailey et al., 1989). A number of medicinal/culinary herbs have been reported to yield hypoglycemic effects in subjects with diabetes. These include cinnamon, cloves, bay leaves, turmeric (Khan et al., 1990), bitter melon (Srivastava et al., 1993; Raman and Lau, 1996), gurmar (Basakaran et al., 1990; Shanmugasundaram et al., 1990; Bishayee and Chatterjee, 1994), Korean ginseng (Sotaniemi et al., 1995), onions and garlic (Koch and Lawson, 1996), holy basil (Rai et al., 1997).

Table 2. Chemical drugs and drugs from medicinal plants.

Drugs

Chemical Action/Clinical Use

Plant Source

 

Acetyldigoxin

Cardiotonic  

Digitalis lanata

 

Adoniside

Cardiotonic

Adonis vernalis

 

Aescin

Anti-inflammatory

Aesculus hippocastanum

 

Aes culetin

Anti-dysentery

Frazinus rhychophylla

 

Agrimophol

Anthelmintic

Agrimonia supatoria

 

Ajmalicine

Circulatory disorders

Rauvolfia sepentina

 

Allantoin

Vulnerary

Several plants

 

Allyl isothiocyanate

Rubefacient

Brassica nigra

 

Anabesine

Skeletal muscle relaxant

Anabasis sphylla

 

Andrographolide

Baccillary dysentery

Andrographis paniculata

 

Anisodamine

Anticholinergic

Anisodus tanguticus

 

Anisodine

Anticholinergic

Anisodus tanguticus

 

Arecoline

Anthelmintic

Areca catechu

 

Asiaticos ide

Vulnerary

Centella asiatica

 

Atropine

Anticholinergic

Atropa belladonna

 

Benzyl benzoate

Scabicide

Several plants

 

Berberine

Bacillary dysentery

Berberis vulgaris

 

Bergenin

Antitussive

Ardisia japonica

 

Betulinic acid

Anticancerous

Betula alba

 

Borneol

 

Antipyretic, analges ic,

antiinflammatory 

Several plants   

 

 

Bromelain

Anti-inflammatory,proteolytic

Ananas cosmosus

 

Caffeine

CNS stimulant

Camellia sinensis

 

Camphor

Rubefacient

Cinnamomum camphora

 

Camptothecin

Anticancerous

Camptotheca acuminate

 

(+)-Catechin

Haemos tatic

Potentilla fragar ioides

 

Chymopapain

Proteolytic, mucolytic

Carica papaya

 

Cis sampeline

Skeletal muscle relaxant

Cissampelos pareira

 

Cocaine coca

Local anaesthetic

Erythroxylum

 

Codeine

Analgesic,        antitus sive

Papaver somniferum

 

Colchiceine amide

Antitumor agent

Colchicum autumnale

 

Colchicine

Antitumor agent, anti-gout

Colchicum autumnale

 

Convallatoxin

Cardiotonic

Convallaria majalis

 

Curcumin

Choleretic

Curcuma longa

 

Cynarin

Choleretic

Cynara s colymus

 

Danthron

Laxative

Cassia species

 

Demecolcine

Antitumor agent

Colchicum autumnale

 

Des erpidine

Antihypertensive, tranquillizer

Rauvolfia canescens

 

Deslanoside

Cardiotonic

Digitalis lanata

 

L-Dopa

Anti-parkinsonism

Mucuna sp

 

Digitalin

Cardiotonic

Digitalis purpurea

 

Digitoxin

Cardiotonic

Digitalis purpurea

 

Digoxin

Cardiotonic

Digitalis purpurea

Emetine

Amoebicide, emetic

Cephaelis ipecacuanha

Ephedrine

Sympathomimetic, antihis tamine                  

Ephedra sinica

Etoposide

Antitumor agent

Podophyllum peltatum

Galanthamine

Cholinesterase inhibitor

Lycor is squamigera

Gitalin

Cardiotonic

Digitalis purpurea

Glaucarubin

Amoebicide

Simarouba glauca

Glaucine

Antitussive

Glaucium flavum

Glasiovine

Antidepressant

Octea glaziovii

Glycyrrhizin

Sweetener, Addison’s disease

Glycyrrhiza glabra

Gossypol

Male contraceptive

Gossypium species

Hemsleyadin

Bacillary dysentery

Hemsleya amabilis

Hesperidin

Capillary fragility

Citrus species

Hydrastine

Hemostatic, astringent

Hydrastis Canadensis

Hyoscyamine

Anticholinergic

Hyoscyamus niger

Irinote

Anti cancer,antitumour agent

Camptotheca acuminate

Kaibic acud

Ascaricide

Digenea simplex

Kawain

Tranquillizer

Piper methysticum

Kheltin

Bronchodilator

Ammi visage

Lanatosides A, B, C

Cardiotonic

Digitalis lanata

Lapachol

Anticancer, antitumor

Tabebuia sp.

a-Lobeline

Smoking deterrant, respiratory stimulant   

Lobelia inflate

Menthol

Rubefacient

Mentha species

Methyl salicylate

Rubefacient

Gaultheria procumbens

Monocrotaline

Antitumor agent (topical)

Crotalaria sessiliflora

Morphine

Analgesic

Papaver somniferum

Neoandrographolide

Dysentery

Andrographis paniculata

Nicotine

Ins ecticide

Nicotiana tabacum

Nordihydroguaiaretic acid    

Antioxidant

Lar rea divaricata

Nos capine

Antitussive

Papaver somniferum

Ouabain

Cardiotonic

Strophanthus gratus

Pachycarpine

Oxytocic

Sophora pschycarpa

Palmatine

Antipyretic,detoxicant

Coptis japonica

Papain

Proteolytic, mucolytic

Carica papaya

Papavarine

Smooth muscle relaxant

Papaver somniferum

Phyllodulcin

Sweetner

Hydrangea macrophylla

Physostigmine

Cholinesterase Inhibitor             

Physostigma venenosum

Picrotoxin

Analeptic

Anamirta cocculus

Pilocarpine

Parasympathomimetic

Pilocarpus jaborandi

Pinitol

Expectorant

Several plants

Podophyllotoxin

Antitumor anticancer agent

Podophyllum peltatum

Protoveratrines A, B

Antihypertens ives

Veratrum album

Pseudoephredrine

* Sympathomimetic

Ephedra sinica

Pseudoephedrine,

nor- Sympathomimetic

Ephedra sinica

Quinidine

Antiarrhythmic

Cinchona ledgeriana

Quinine

Antimalarial,antipyretic

Cinchona ledgeriana

Qulsqualic acid

Anthelmintic

Quisqualis indica

Rescinnamine

Antihypertensive, tranquillizer

Rauvolfia serpentine

Res erpine

Antihypertensive, tranquillizer

Rauvolfia serpentine

Rhomitoxin

Antihypertensive, tranquillizer

Rhododendron molle

Rorifone

Antitussive

Rorippa indica

Rotenone

Piscicide, Insecticide

Lonchocarpus nicou

Rotundine

Analagesic, sedative, traquillizer

Stephania sinica

Rutin

Capillary fragility

Citrus species

Salicin

Analgesic

Salix alba

Sanguinarine

Dental plaque inhibitor

Sanguinaria Canadensis

Santonin

Ascaricide

Artemisia mar itma

Scillarin A

Cardiotonic

Urginea maritime

Scopolamine

Sedative

Datura species

Sennosides A, B

Laxative

Cassia species

Silymarin

Antihepatotoxic

Silybum marianum

Sparteine

Oxytocic

Cytisus scoparius

Stevioside

Sweetner

Stevia rebaudiana

Strychnine

CNS stimulant

Strychnos nux-vomica

Toxol

Antitumor agent

Taxus brevifolia

Teniposide

Antitumor agent

Podophyllum peltatum

a- ntiemetic

occular tens ion decrease

Cannabis sativa

Tetrahydropalmatine

sic, sedative, traquillizer

Corydalis ambigua

Tetrandrine

Antihypertensive

Stephania tetrandra

Theobromine

Diuretic, vasodilator

Theobroma cacao

Theophylline

Diuretic, bronchodilator

Theobroma cacao and others

Thymol

Antifungal (topical)

Thymus vulgaris

Topotecan

Antitumor, anticancer agent

Camptotheca acuminate

Trichos anthin

Abortifacient

Trichosanthes kirilowii

Tubocurarine

Skeletal muscle relaxant

Chondodendron tomentosum

Valapotriates

Sedative

Valeriana officinalis

Vasicine

Cerebral stimulant

Vinca minor

Vinblastine

Antitumor, Antileukemic agent

Catharanthus roseus

Vincristine

Antitumor, Antileukemic agent

Catharanthus roseus

Yohimbine

Aphrodis iac

Pausinystalia yohimbe

Yuanhuacine

Abortifacient

Daphne genkwa

 

 

       Plant-Derived Drugs from Chinese Herbal Remedies and Other Systems of Traditional Medicine

During the past decade, traditional systems of medicine have become a topic of global importance. Current estimates suggest that, in many developing countries, a large proportion of populations relies heavily on traditional practices and medicinal plants may be available in these countries, herbal medicines (phytomedicines) have often maintained popularity for historical and cultural reasons. Concurrently, many people in developed countries have begun to turn to alternative or complementary therapies, including medicinal herbs.

 

Chinese Traditional Medicine

Traditions of plant-collecting and plant based medications have been handed down from generation to generation. For thousands of years, plant-derived (herbal) remedies have remained a vital part of traditional Chinese medicine, and even today constitute about a 30% to 50% proportion of the total drug therapy for a fifth of the world’s population who live in the People’s Republic of China (PRC).  Of about 5500 medicinal plants used in traditional Chinese medicine, between 300 and 500 are commonly used in regular prescriptions.  One drug that has been in use in China for at least 5000 years in Ephedra sinica (Ma huang), from which the potent sympathomimetic amine ephedrine was isolated and pharmacologically tested in the early years of this century, and is now used in western medicine in the form of various salts to combat bronchial asthma. Recently phytochemical investigation on plants used in Chinese traditional medicine, both in the PRC and elsewhere, have led to the discovery of several hundred pharmacologically active substances, with about 60 new drugs being derived from such compounds (Xiao and Fu, 1987).

  

Examples of plant drugs that are of use in the PRC include the tropane alkaloids anisodamine and anisodine  from Scopolia tangutica, which are employed as a mild, naturally acting antichol inergic agent for septic shock in cases of bacillary dysentery, and as a migraine treatment, respectively.  An isoquinoline alkaloid, racemic tetrahydropalmatine, from Corydalis ambigua is used as an analgesic and tranquilizer, and indirubrin , a nitrogen-containing metabolite produced by Indigofera tinctoria, is effective in the treatment of chronic myelocytic leukemia.

Conclusion of our research article reported that traditional knowledge on medicinal plants plays a vital role in the primary health care and has potential of the discovery of new herbal drugs, new sources of pharmaceuticals, contraceptives and for sustainable utilization of medicinal plants genetic resources and their conservation.

 

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