NATURAL PRODUCTS FROM PLANT BIODIVERSITY AND MALARIA

Dr. Joseph M Nguta, Department of Public Health, Pharmacology and Toxicology

UNIVERSITY OF NAIROBI

Natural products from plants as drug sources

The material culture of every civilization throughout the world is based more on plants than on animals.

People of the earth have depended for along time on plants as a source of food, clothing, shelter, transportation, medicines, rituals and traditions

The plant kingdom met the health needs of humans when no synthetic drugs were available and no concept of surgical management existed

Cont.

The world has witnessed growing scientific and commercial interests in medicinal plants, mainly due to their immense economic potential and the widespread cultural acceptability of plant based products.

An inventory of medicinal plants compiled by WHO lists 21,000 species of medicinal plants.

According to WHO, 80% of the 5 billion people in the dev. World rely on herbal remedies for their basic health care needs.

Cont.

The dev. world is rich in natural resourses, including floral resources

However, the south's floral wealth has not been utilized for the benefit of its people.

Ethnopharmacology to modern medicine

Drug/Chemical Action Plant Source

Acetyldigoxin Cardiotonic Digitalis lanata (Grecian foxglove, woolly foxglove)

Adoniside Cardiotonic Adonis vernalis (pheasant's eye, red chamomile)

Aescin Antiinflammatory Aesculus hippocastanum (horse chestnut)

Aesculetin Antidysentery Frazinus rhychophylla

Agrimophol Anthelmintic Agrimonia supatoria

Ajmalicine Treatment for circulatory disorders Rauvolfia sepentina

Allantoin Vulnerary Several plants

Allyl isothiocyanate Rubefacient Brassica nigra (black mustard)

Anabesine Skeletal muscle relaxant Anabasis sphylla

Andrographolide Treatment for baccillary dysentery Andrographis paniculata

Anisodamine Anticholinergic Anisodus tanguticus

Anisodine Anticholinergic Anisodus tanguticus

Arecoline Anthelmintic Areca catechu (betel nut palm)

Asiaticoside Vulnerary Centella asiatica (gotu cola)

Ethnopharmacology to modern medicine (Cont.)

Drug/Chemical Action Plant Source

Atropine Anticholinergic Atropa belladonna (deadly nightshade)

Benzyl benzoate Scabicide Several plants

Berberine Treatment for bacillary dysentery Berberis vulgaris (common barberry)

Bergenin Antitussive Ardisia japonica (marlberry)

Betulinic acid Anticancerous Betula alba (common birch)

Hyoscyamine Anticholinergic Hyoscyamus niger (black henbane, stinking nightshade, henpin)

Irinotecan Anticancer, antitumor agent Camptotheca acuminata

Kaibic acud Ascaricide Digenea simplex (wireweed)

Kawain Tranquilizer Piper methysticum (kava kava)

Kheltin Bronchodilator Ammi visaga

Lanatosides A, B, C Cardiotonic Digitalis lanata (Grecian foxglove, woolly foxglove)

Lapachol Anticancer, antitumor Tabebuia species (trumpet tree)

a-Lobeline Smoking deterrant, respiratory stimulant Lobelia inflata (Indian tobacco)

Menthol Rubefacient Mentha species (mint)

Ethnopharmacology to modern medicine (Cont.)

Drug/Chemical Action Plant Source

Monocrotaline Topical antitumor agent Crotalaria sessiliflora

Morphine Analgesic Papaver somniferum (poppy)

Neoandrographolide Treatment of dysentery Andrographis paniculata

Nicotine Insecticide Nicotiana tabacum (tobacco)

Nordihydroguaiaretic acid Antioxidant Larrea divaricata (creosote bush)

Noscapine Antitussive Papaver somniferum (poppy)

Ouabain Cardiotonic Strophanthus gratus (ouabain tree)

Pachycarpine Oxytocic Sophora pschycarpa

Palmatine Antipyretic, detoxicant Coptis japonica (Chinese goldenthread, goldthread, Huang-Lia)

Papain Proteolytic, mucolytic Carica papaya (papaya)

Papavarine Smooth muscle relaxant Papaver somniferum (opium poppy, common poppy)

Phyllodulcin Sweetener Hydrangea macrophylla (bigleaf hydrangea, French hydrangea)

Physostigmine Cholinesterase inhibitor Physostigma venenosum (Calabar bean)

Picrotoxin Analeptic Anamirta cocculus (fish berry)

Pilocarpine Parasympathomimetic Pilocarpus jaborandi (jaborandi, Indian hemp)

Ethnopharmacology to modern medicine (Cont.)

Drug/Chemical Action Plant Source

Podophyllotoxin Antitumor, anticancer agent Podophyllum peltatum (mayapple)

Protoveratrines A, B Antihypertensives Veratrum album (white false hellebore)

Pseudoephredrine Sympathomimetic Ephedra sinica (ephedra, ma huang)

nor-pseudoephedrine Sympathomimetic Ephedra sinica (ephedra, ma huang)

Quinidine Antiarrhythmic Cinchona ledgeriana (quinine tree)

Quinine Antimalarial, antipyretic Cinchona ledgeriana (quinine tree)

Qulsqualic acid Anthelmintic Quisqualis indica (Rangoon creeper, drunken sailor)

Rescinnamine Antihypertensive, tranquilizer Rauvolfia serpentina

Reserpine Antihypertensive, tranquilizer Rauvolfia serpentina

Rhomitoxin Antihypertensive, tranquilizer Rhododendron molle (rhododendron)

Rorifone Antitussive Rorippa indica

Rotenone Piscicide, Insecticide Lonchocarpus nicou

Rotundine Analagesic, sedative, traquilizer Stephania sinica

Rutin Treatment for capillary fragility Citrus species (e.g., orange, grapefruit)

Ethnopharmacology to modern medicine (Cont.)

Drug/Chemical Action Plant Source

Sanguinarine Dental plaque inhibitor Sanguinaria canadensis (bloodroot)

Santonin Ascaricide Artemisia maritma (wormwood)

Scillarin A Cardiotonic Urginea maritima (squill)

Scopolamine Sedative Datura species (e.g., Jimsonweed)

Sennosides A, B Laxative Cassia species (cinnamon)

Silymarin Antihepatotoxic Silybum marianum (milk thistle)

Sparteine Oxytocic Cytisus scoparius (scotch broom)

Stevioside Sweetener Stevia rebaudiana (stevia)

Strychnine CNS stimulant Strychnos nux-vomica (poison nut tree)

Taxol Antitumor agent Taxus brevifolia (Pacific yew)

Teniposide Antitumor agent Podophyllum peltatum (mayapple or mandrake)

a-Tetrahydrocannabinol (THC) Antiemetic, decreases occular tension Cannabis sativa (marijuana)

Tetrahydropalmatine Analgesic, sedative, tranquilizer Corydalis ambigua

Tetrandrine Antihypertensive Stephania tetrandra

Theobromine Diuretic, vasodilator Theobroma cacao (cocoa)

Theophylline Diuretic, bronchodilator Theobroma cacao and others (cocoa, tea)

Thymol Topical antifungal Thymus vulgaris (thyme)

Ethnopharmacology to modern medicine (Cont.)

Drug/Chemical Action Plant source

Trichosanthin Abortifacient Trichosanthes kirilowii (snake gourd)

Tubocurarine Skeletal muscle relaxant Chondodendron tomentosum (curare vine)

Valapotriates Sedative Valeriana officinalis (valerian)

Vasicine Cerebral stimulant Vinca minor (periwinkle)

Vinblastine Antitumor, Antileukemic agent Catharanthus roseus (Madagascar periwinkle)

Vincristine Antitumor, Antileukemic agent Catharanthus roseus (Madagascar periwinkle)

Yohimbine Aphrodisiac Pausinystalia yohimbe (yohimbe)

Yuanhuacine Abortifacient Daphne genkwa (lilac)

Yuanhuadine Abortifacient Daphne genkwa (lilac)

Antimalarial plants in South Coast, Kenya

Nguta et al., Journal of ethnopharmacology 2010a, 128: 424-432

Malaria is the most difficult problem afflicting people in the tropics

In Africa, more than 100 million people are infected annually, with a mortality of 1-1.5m a year

Currently the drug of choice is artemesinin and its derivatives

High rate of resistance development to drugs by the parasite makes the necessity for research in new antimalarial drugs

One possible solution is to carry out research on to the traditionally used herbal remedies

STUDY AREA Msambweni district

Conducting an interview

Herbal Clinic

Objective of the studyTo establish an inventory of plants and

formulations used to manage Malaria in Msambweni community

The study

How do they identify malaria?Which plants do they use to manage malaria?Which is the most preferred plant?Which part of plant do they use?How is it formulatedWhich is the route of administration?Are the plants readily available?Are the plants used safe?

How the Study was done Semistructured questionnaires and interviews Focused group discussion Botanical identification of the collected plants by

a taxonomist

Information gathered included plant species parts used plant habit method of preparation dosage vernacular names

Ethnodiagnosis

The most frequently mentioned symptoms

fever joint pains vomiting tiredness Loss of appetite headache

Commonly used plants

27 species in 24 genera distributed in 20 families were documented.

13 species were reported for the first time The most commonly used species were Azadirachta indica (L) Burm. (95%) Zanthoxylum chalybeum (Eng) Engl. (25%) Aloe deserti Berger. (25%) Harrisonia abyssinica Oliv. (15%) Ricinus communis L.(10%)

Habit of the species used in treatment of malaria

41%

33%

22%

4% Shrub

HerbTreeLiana

Part of the species used in treatment of malaria.

Percentage frequency

Column1

Column20%

10%

20%

30%

40%

50%

60%

Percentage frequency

Conclusion The commonly used plants were Azadirachta

indica (L) Burm, Zanthoxylum chalybeum (Eng) Engl and Aloe deserti Berger.

13 plant species are documented for the first time for the treatment of malaria

Some species documented in this study have been widely used as antimalarials in other continents e.g Ricinus communis, Lantana camara

The leaves were the most commonly used part Roots were the second most commonly used plant

part-and this calls for conservation and good harvesting practices

Way forward

Toxicological screening of crude extracts as used by the south coast community

Acknowledgements

The Carnegie Corporation of New York

Nairobi Node-RISE-AFNNET)

The community of Msambweni district

University of Nairobi

COLLABORATORS: KIAMA GITAHI JAMES MBARIA DANIEL GAKUYA PETER GATHUMBI

THANK YOU FOR ACTIVE PARTICIPATION