n. taking unfair advantage of another’s misfortune, weakness, or *vulnerability. In medical ethics, the principle of *nonmaleficence means that doctors have an active duty to avoid any exploitation of their patients. This is usually held to require that professional boundaries are maintained and to prohibit personal or sexual relationships between professionals and their patients. Another example of potential exploitation is the practice of holding clinical trials and conducting research in developing countries when the treatments being tested are designed for sale and use in the West and will not be made available to those who acted as research participants or subjects.
Rauvolfia serpentinaApocynaceaeSan: SarpagandhaHin: ChandrabhagaMal: Sarpagandhi, AmalporiTam: Chivan amelpodiKan: SutranbhiTel: PatalagandhiIntroduction: Serpentwood is an erect, evergreen , perennial undershrub whose medicinal use has been known since 3000 years. Its dried root is the economical part which contains a number of alkaloids of which reserpine, rescinnamine, deserpidine, ajamalacine, ajmaline, neoajmalin, serpentine, -yohimbine are pharmacologically important. The root is a sedative and is used to control high blood pressure and certain forms of insanity. In Ayurveda it is also used for the treatment of insomnia, epilepsy, asthma, acute stomach ache and painful delivery. It is used in snake-bite, insect stings, and mental disorders. It is popular as “Madman’s medicine” among tribals. ‘Serpumsil’ tablet for high blood pressure is prepared from Rauvolfia roots. Reserpine is a potent hypotensive and tranquillizer but its prolonged usage stimulates prolactine release and causes breast cancer. The juice of the leaves is used as a remedy for the removal of opacities of the cornea.Distribution: Rauvolfia serpentina is native to India. Several species of Rauvolfia are observed growing under varying edaphoclimatic conditions in the humid tropics of India, Nepal, Burma, Thailand, Bangladesh, Indonesia , Cambodia, Philippines and Sri Lanka. In India, it is cultivated in the states of Uttar Pradesh, Bihar, Tamil Nadu, Orissa, Kerala, Assam, West Bengal and Madhya Pradesh (Dutta and Virmani, 1964). Thailand is the chief exporter of Rauvolfia alkaloids followed by Zaire, Bangladesh, Sri Lanka, Indonesia and Nepal. In India, it has become an endangered species and hence the Government has prohibited the exploitation of wild growing plants in forest and its export since 1969.Botany: Plumier in 1703 assigned the name Rauvolfia to the genus in honour of a German physcian -Leonhart Rauvolf of Augsburg. The genus Rauvolfia of Apocynaceae family comprises over 170 species distributed in the tropical and subtropical parts of the world including 5 species native to India. The common species of the genus Rauvolfia and their habitat as reported by Trivedi (1995) are given below.R. serpentina Benth. ex Kurz.(Indian serpentwood) - India ,Bangladesh, Burma, Sri Lanka, Malaya, IndonesiaR. vomitoria Afz. (African serpentwood) - West Africa, Zaire, Rwanda, Tanzania R. canescens Linn. syn. R. tetraphylla (American serpentwood) - America, India R. mombasina - East Africa , Kenya, MozambiqueR. beddomei - Western ghats and hilly tracts of KeralaR. densiflora - Maymyo, IndiaR. microcarpa - ThandaungR. verticillata syn. R. chinensis - HemslR. peguana - Rangoon-Burma hillsR. caffra - Nigeria, Zaire, South AfricaR. riularis - Nmai valleyR. obscura - Nigeria, ZaireR. serpentina is an erect perennial shrub generally 15-45 cm high, but growing upto 90cm under cultivation. Roots nearly verticle, tapering up to 15 cm thick at the crown and long giving a serpent-like appearance, occasionally branched or tortuous developing small fibrous roots. Roots greenish-yellow externally and pale yellow inside, extremely bitter in taste. Leaves born in whorls of 3-4 elliptic-lanceolate or obovate, pointed. Flowers numerous borne on terminal or axillary cymose inflorscence. Corolla tubular, 5-lobed, 1-3 cm long, whitish-pink in colour. Stamens 5, epipetalous. Carpels 2, connate, style filiform with large bifid stigma. Fruit is a drupe, obliquely ovoid and purplish black in colour at maturity with stone containing 1-2 ovoid wrinkled seeds. The plant is cross-pollinated, mainly due to the protogynous flowers (Sulochana ,1959).Agrotechnology: Among the different species of Rauvolfia, R. serpentina is preferred for cultivation because of higher reserpine content in the root. Though it grows in tropical and subtropical areas which are free from frost, tropical humid climate is most ideal. Its common habitats receive an annual rain fall of 1500-3500 mm and the annual mean temperature is 10-38 C. It grows up to an elevation of 1300-1400m from msl. It can be grown in open as well as under partial shade conditions. It grows on a wide range of soils. Medium to deep well drained fertile soils and clay-loam to silt-loam soils rich in organic matter are suitable for its cultivation. It requires slightly acidic to neutral soils for good growth.The plant can be propagated vegetatively by root cuttings, stem cuttings or root stumps and by seeds. Seed propagation is the best method for raising commercial plantation. Seed germination is very poor and variable from 10-74%. Seeds collected during September to November give good results. It is desirable to use fresh seeds and to sock in 10% sodium chloride solution. Those seeds which sink to the bottom should only be used. Seeds are treated with ceresan or captan before planting in nursery to avoid damping off. Seed rate is 5-6 kg/ha. Nursery beds are prepared in shade, well rotten FYM is applied at 1kg/m2 and seeds are dibbled 6-7cm apart in May-June and irrigated.Two months old seedlings with 4-6 leaves are transplanted at 45-60 x 30 cm spacing in July -August in the main field. Alternatively, rooted cuttings of 2.5-5cm long roots or 12-20cm long woody stems can also be used for transplanting. Hormone (Seradix) treatment increases rooting. In the main field 10-15 t/ha of FYM is applied basally. Fertilisers are applied at 40:30:30kg N: P2O5 :K2O/ha every year. N is applied in 2-3 splits. Monthly irrigation increases the yield. The nursery and the main field should be kept weed free by frequent weeding and hoeing. In certain regions intercroping of soybean, brinjal, cabbage, okra or chilly is followed in Rauvolfia crop.Pests like root grubs (Anomala polita), moth (Deilephila nerii), caterpillar (Glyophodes vertumnalis), black bugs and weevils are observed on the crop, but the crop damage is not serious. The common diseases reported are leaf spot (Cercospora rauvolfiae, Corynespora cassiicola), leaf blotch (Cercospora serpentina), leaf blight (Alternaria tenuis), anthracnose (Colletotrichum gloeosporioides), die back (Colletotrichum dematrium), powdery mildew (Leviellula taurica), wilt (Fusarium oxysporum), root-knot (Meloidogyne sp.), mosaic and bunchy top virus diseases. Field sanitation, pruning and burning of diseased parts and repeated spraying of 0.2% Dithane Z-78 or Dithane M-45 are recommended for controlling various fungal diseases. Rauvolfia is harvested after 2-3 years of growth. The optimum time of harvest is in November -December when the plants shed leaves, become dormant and the roots contain maximum alkaloid content. Harvesting is done by digging up the roots by deeply penetrating implements (Guniyal et al, 1988).Postharvest technology: The roots are cleaned washed cut into 12-15cm pieces and dried to 8-10% moisture.The dried roots are stored in polythene lined gunny bags in cool dry place to protect it from mould. The yield is 1.5-2.5 t/ha of dry roots. The root bark constitutes 40-45% of the total weight of root and contributes 90% of the total alkaloids yield.Properties and activity: Rauvolfia root is bitter, acrid, laxative, anthelmintic, thermogenic, diuretic and sedative. Over 200 alkaloids have been isolated from the plant. Rauvolfia serpentina root contains 1.4-3% alkaloids. The alkaloids are classsified into 3 groups, viz, reserpine, ajmaline and serpentine groups. Reserpine group comprising reserpine, rescinnamine, deserpine etc act as hypotensive, sedative and tranquillising agent. Overdose may cause diarrhoea, bradycardia and drowsiness. Ajmaline, ajmalicine, ajmalinine, iso-ajmaline etc of the ajmaline group stimulate central nervous system, respiration and intestinal movement with slight hypotensive activity. Serpentine group comprising serpentine, sepentinine, alstonine etc is mostly antihypertensive. (Husain,1993; Trivedi, 1995; Iyengar, 1985).... serpentwood
“There is a large body of opinion to support the belief that a herb that has, without ill-effects, been used for centuries and capable of producing convincing results, is to be regarded as safe and effective.” (BHMA) Claims for efficacy are based on traditional use and inclusion in herbals and pharmacopoeias over many years. Their prescription may be prefixed by: “For symptomatic relief of . . .” or “An aid in the treatment of . . .”
To establish efficacy of treatment for a named specific disease by herbs, the DHSS requires scientific data presented to the Regulatory authorities for consideration and approval.
A product is not considered a herbal remedy if its active principle(s) have been isolated and concentrated, as in the case of digitalis from the Foxglove. (MAL 2. Guidance notes)
A herbal product is one in which all active ingredients are of herbal origin. Products that contain both herbal and non-vegetable substances are not considered herbal remedies: i.e. Yellow Dock combined with Potassium Iodide.
The British Government supports freedom of the individual to make an informed choice of the type of therapy he or she wishes to use and has affirmed its policy not to restrict the general availability of herbal remedies. Provided products are safe and are not promoted by exaggerated claims, the future of herbal products is not at risk. A doctor with knowledge and experience of herbal medicine may prescribe them if he considers that they are a necessary part of treatment for his patient.
Herbalism is aimed at gently activating the body’s defence mechanisms so as to enable it to heal itself. There is a strong emphasis on preventative treatment. In the main, herbal remedies are used to relieve symptoms of self-limiting conditions. They are usually regarded as safe, effective, well-tolerated and with no toxicity from normal use. Some herbal medicines are not advised for children under 12 years except as advised by a manufacturer on a label or under the supervision of a qualified practitioner.
World Health Organisation Guidelines
The assessment of Herbal Medicines are regarded as:–
Finished, labelled medicinal products that contain as active ingredients aerial or underground parts of plants, or other plant material, or combinations thereof, whether in the crude state or as plant preparations. Plant material includes juices, gums, fatty oils, essential oils, and any other substances of this nature. Herbal medicines may contain excipients in addition to the active ingredients. Medicines containing plant material combined with chemically defined active substances, including chemically defined, isolated constituents of plants, are not considered to be herbal medicines.
Exceptionally, in some countries herbal medicines may also contain, by tradition, natural organic or inorganic active ingredients which are not of plant origin.
The past decade has seen a significant increase in the use of herbal medicines. As a result of WHO’s promotion of traditional medicine, countries have been seeking the assistance of WHO in identifying safe and effective herbal medicines for use in national health care systems. In 1989, one of the many resolutions adopted by the World Health Assembly in support of national traditional medicine programmes drew attention to herbal medicines as being of great importance to the health of individuals and communities (WHA 42.43). There was also an earlier resolution (WHA 22.54) on pharmaceutical production in developing countries; this called on the Director-General to provide assistance to the health authorities of Member States to ensure that the drugs used are those most appropriate to local circumstances, that they are rationally used, and that the requirements for their use are assessed as accurately as possible. Moreover, the Declaration of Alma-Ata in 1978 provided for inter alia, the accommodation of proven traditional remedies in national drug policies and regulatory measures. In developed countries, the resurgence of interest in herbal medicines has been due to the preference of many consumers for products of natural origin. In addition, manufactured herbal medicines from their countries of origin often follow in the wake of migrants from countries where traditional medicines play an important role.
In both developed and developing countries, consumers and health care providers need to be supplied with up-to-date and authoritative information on the beneficial properties, and possible harmful effects, of all herbal medicines.
The Fourth International Conference of Drug Regulatory Authorities, held in Tokyo in 1986, organised a workshop on the regulation of herbal medicines moving in international commerce. Another workshop on the same subject was held as part of the Fifth International Conference of Drug Regulatory Authorities, held in Paris in 1989. Both workshops confined their considerations to the commercial exploitation of traditional medicines through over-the-counter labelled products. The Paris meeting concluded that the World Health Organisation should consider preparing model guidelines containing basic elements of legislation designed to assist those countries who might wish to develop appropriate legislation and registration.
The objective of these guidelines, therefore, is to define basic criteria for the evaluation of quality, safety, and efficacy of herbal medicines and thereby to assist national regulatory authorities, scientific organisations, and manufacturers to undertake an assessment of the documentation/submission/dossiers in respect of such products. As a general rule in this assessment, traditional experience means that long-term use as well as the medical, historical and ethnological background of those products shall be taken into account. Depending on the history of the country the definition of long-term use may vary but would be at least several decades. Therefore the assessment shall take into account a description in the medical/pharmaceutical literature or similar sources, or a documentation of knowledge on the application of a herbal medicine without a clearly defined time limitation. Marketing authorisations for similar products should be taken into account. (Report of Consultation; draft Guidelines for the Assessment of Herbal Medicines. World Health Organisation (WHO) Munich, Germany, June 1991) ... herbal medicine
Ravensara aromatica
FAMILY: Lauraceae
SYNONYMS: Madagascar clove-nutmeg, aromatic ravensare, Ravensara anisata, Agatophyllum aromaticum.
GENERAL DESCRIPTION: The genus Ravensara includes many species of evergreen trees or shrubs native to Madagascar and the Comoro Islands. These evergreen trees can grow up to 30 metres tall in rainforests, usually on all type of soils. The best-known species of this genus is R. aromatica used for its essential oil. It grows to a height of about 20 metres with several buttress roots at the base, with reddish bark, dark green shiny leaves and small yellow-green flowers. The fruit, a fleshy berry, are an important food source for birds. All parts of the tree are aromatic.
DISTRIBUTION: R. aromatica is native to Madagascar and once thrived in the rainforests, but is now an endangered species due to de-forestation and over-exploitation. By the early part of this century, this species required protection as the production of the essential oil from the bark, used by the pharmaceutical industry, was particularly destructive as it required felling the trees. Only the leaves can now be used for oil production, to prevent cutting down the whole tree. There is now a conservation programme in place to protect these trees: it is therefore important to obtain the essential oil of the leaf from sustainable sources.
OTHER SPECIES: There are over 30 species of Ravensara that grow in Madagascar. The common name of the genus Ravensara is actually a latinization of the Malagasy term ravintsara which means ‘good leaves’, a term originally used by the natives to describe another species of tree. European botanists in the nineteenth century made several attempts to classify the various indigenous aromatic trees of Madagascar, but due to the similarity of the two names ‘ravintsara’ and ‘ravensara’ they came to be used almost interchangeably. The botanical confusion between these two species has continued to cause a great deal of uncertainty as to their precise origins. In fact, the essential oils derived from these two species are very different aromatically as well as in their chemical composition. However, most of so-called ‘ravensara’ oil from Madagascar, is actually produced from the Cinnamomum camphora species (even if it is said to derive from R. aromatica) so great care needs to be taken in identifying the correct source of each oil. See also entry for Ravintsara.
HERBAL/FOLK TRADITION: In Madagascar, this genus of trees is commonly called hazomanitra, meaning ‘tree that smells’, as the whole part of the plant is aromatic. Traditionally, the Malagasy people used the bark and stem as a tonic and as an antibacterial medicine. The leaves were also burnt in homes after a death to prevent the spread of disease while the anise-flavoured bark was used in the production of local rum. The oil from the Ravensara genus is referred to locally as ‘the oil that heals’ because it is used for so many different conditions. The essential oil from the bark, R. anisata (a synonym for R. aromatica) is known as ‘havozo’ and has a strong anise-like odour.
ACTIONS: Antiviral, antibacterial, antifungal, anti-infectious, antiseptic, antispasmodic, expectorant, immune-stimulant.
EXTRACTION: 1. Ravensara oil is steam distilled from the leaves of the plant. 2. The essential oil distilled from the bark is called havozo. 3. An essential oil is also extracted occasionally from the fleshy fruits or berries.
CHARACTERISTICS: 1. Ravensara oil (from the leaf) has a sweet, fresh, slightly lemony, licorice-like scent with an earthy undertone. 2. Havozo (from the bark) has a fresh, strong aniseed-like odour.
PRINCIPAL CONSTITUENTS: 1. The oil from the leaf contains relatively small amounts of methyl chavicol (estragole), myrcene, a-pinene and linalool with the main constituents being limonene (approx. 13–22 per cent) and sabinene (approx. 10–16 per cent) with very little 1,8-cineole (1.8–3.3 per cent). 2. Havozo (bark oil) has a high methyl chavicol content (up to 90 per cent).
SAFETY DATA: 1. Ravensara (R. aromatica) is generally considered a safe oil (non-toxic and non-irritant) although it is best avoided during pregnancy. 2. Havozo oil is not recommended for use in aromatherapy due to its high methyl chavicol content, as it is a suspected carcinogen. Research has shown, nevertheless this oil has potent anti-microbial properties, being active against E. coli.
AROMATHERAPY/HOME: USE
Skin care: Chickenpox, cold sores, herpes (all types), shingles.
Circulation muscles and joints: Aching limbs, arthritis, cramp, gout, muscle fatigue, rheumatism.
Respiratory system: Bronchitis, colds, congestion, influenza, sinusitis, throat and lung infections, whooping cough.
Immune system: Viral infections especially herpes, hepatitis, chicken pox.
Nervous system: Anxiety, insomnia, nervous tension, stress.
OTHER USES: Ravensara species have been used for a long time to produce essential oils for the pharmaceuticals industry. In perfumery usage, it is employed as a middle note.... ravensara
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