Neem oil is a vegetable oil pressed from the seeds of Azadirachta indica, an evergreen tree which is endemic to the Indo-Pakistan sub-continent
and has been introduced to many other areas in the tropics.
Use
Neem oil is not used for cooking purposes but, in India, is used for preparing cosmetics (soap, hair products, body hygiene creams, hand creams) and in Ayurvedic, Urani 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.
Characteristics
Neem seed oil is a thick dark brown semisolid with bitter taste and 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.
The method of processing is likely to affect the composition of the oil, since the methods used,
such as pressing, solvent extraction or steam extraction are unlikely to remove exactly the same
mix of components in the same proportions.
The oil can be obtained through pressing (crushing) of the seed kernel both through cold pressing or through a process incorporating temperature controls. Neem seed oil can also be obtained by steam extraction or solvent extraction of the seed kernels, although the composition of oils obtained by different extraction techniques may differ.
The yield that can be obtained from neem seed kernels varies also widely in literature and varies from 25% to 45%.
Neem oil also contains steroids (campesterol, beta-sitosterol , stigmasterol) and a plethora of triterpenoids of which Azadirachtin is the most well known and studied.
Scientific references
- 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