Neem oil

Neem oil is a vegetable oil pressed from the fruits and seeds of Neem (Azadirachta indica), an evergreen tree which is endemic to the Indian sub-continent and has been introduced to many other areas in the tropics. It is perhaps the most important of the commercially available products of neem.

Characteristics
Neem oil is generally light to dark brown, bitter and has a rather strong odour that is said to combine the odours of peanut and garlic. It comprises mainly triglycerides and large amounts of triterpenoid compounds, which are responsible for the bitter taste. It is hydrophobic in nature and in order to emulsify it in water for application purposes, it must be formulated with appropriate surfactants.

Neem oil also contains steroids (campesterol, beta-sitosterol, stigmasterol) and a plethora of triterpenoids of which Azadirachtin is the most well known and studied. The Azadirachtin content of Neem Oil varies from 300ppm to over 2000ppm depending on the quality of the neem seeds crushed.

Uses
Neem oil is not used for cooking purposes but, in India and Bangladesh, it is used for preparing cosmetics (soap, hair products, body hygiene creams, hand creams) and in Ayurvedic, Unani and folklore traditional medicine, in the treatment of a wide range of afflictions. The most frequently reported indications in ancient Ayurvedic writings are skin diseases, inflammations and fevers, and more recently rheumatic disorders, insect repellent and insecticide effects.

Traditional Ayurvedic uses of neem include the treatment of fever, leprosy, malaria, ophthalmia and tuberculosis. Various folk remedies for neem include use as an anthelmintic, antifeedant, antiseptic, diuretic, emmenagogue, contraceptive, febrifuge, parasiticide, pediculocide and insecticide. It has been used in traditional medicine for the treatment of tetanus, urticaria, eczema, scrofula and erysipelas. Traditional routes of administration of neem extracts included oral, vaginal and topical use. Neem oil has an extensive history of human use in India and surrounding regions for a variety of therapeutic purposes. Puri (1999) has given an account of traditional uses and therapeutic indications and pharmacological studies of this oil, in his book on neem.

General references

 * Puri, H.S. (1999) Neem:  The Divine Tree. Azadirachta indica.  Harwood Academic Publications, Amsterdam.  ISBN 90-5702-348-2.
 * Evaluation of Cold-Pressed Oil from the Seed Kernels of Azadirachta Indica (A.Juss), Meliaceae (Neem) for use in Listable Therapeutic Goods; Office of Complementary Medicines, Therapeutic Goods Administration (TGA), Australia
 * N. Kaushik and S. Vir. Variations in fatty acid composition of neem seeds collected from the Rajasthan state of India; Biochemical Society Transactions 2000 Volume 28, part 6
 * Schmutterer, H. (Editor) (2002) The Neem Tree: Source of Unique Natural Products for Integrated Pest Management, Medicine, Industry And Other Purposes (Hardcover),2nd Edition, Weinheim,Germany: VCH Verlagsgesellschaft .ISBN 3-527-30054-6
 * Vietmeyer, N. D. (Director) (1992), Neem: A Tree for Solving Global Problems. Report of an ad hoc panel of the Board on Science and Technology for International Development, National Research Council, Washington, DC, USA: National Academy Press. pp.71-72. ISBN 0-309-04686-6