About author :
Amir Khan*, Arvind Kumar Yadav
*Dept. of Biotechnology & Biochemistry
Sardar Bhagwan Singh Post Graduate Institute of Biomedical Sciences & Research, Dehradun, India
Neem (Azadirachta indica), is native of India and naturalized in most of tropical and subtropical countries are of great medicinal value and distributed widespread in the world. The chemical constituents contain many biologically active compounds that can be extracted from neem, including alkaloids, lavonoids, triterpenoids, phenolic compounds, carotenoids, steroids and ketones, biologically most active compound is azadirachtin A-G and azadirachtin E is more effective. Other compounds that have a biologaical activity are salannin, volatile oils, meliantriol and nimbin2. It is evergreen but under severe drought it may shed most or nearly all of its leaves. For thousands of years, the beneficial properties of Neem have been recognized in the Indian tradition. The importance of neem tree has been recognized by the US National Academy of Sciences, which published a report in 1992 entitled ‘Neem – a tree for solving global problems’. The advancement of Neem research has earlier been documented.
Key words: alkaloids, lavonoids, triterpenoids, phenolic, Neem, India
TAXONOMY OF AZADIRACHTA INDICA:
Kingdom: Plantae, Division: Magnoliophyta, Class: Dipsacales, Order: Rutales, Sub-order : Rutinae, Genus: Azadirachta, Species: indica
Abortifacient, anthelminthic, antiyeast, antiulcer, antifertility, antifilarial, antifungal, antiviral, diuretic, antihyperglycemic, antiinflammatory, antimalarial, antinematodal, antipyretic, antispermatogenic, hypercholesteremic, antispasmodic, insecticidal, antitumor, hypoglycaemic, immunomodulator
All parts of tree have been used medicinally for centuries. It has been used in Ayurvedic medicine for more than 4000 years due to its medicinal properties. The earliest Sanskrit medical writings refer to the benefits of Neem’s fruits, seeds, oil, leaves, roots and bark. Each has been used in the Indian Ayurvedic and Unani medicine and now being used in pharmaceutical and cosmetics industries.
Hot water extract of the bark is taken orally by the adults females as a tonic and emmenagouge. Anthraquinone fraction of dried flower, fruits and leaf is taken orally for leprosy. Hot water extract of the flower and leaf is taken orally as an anti-hysteric remedy and used externally to treat wound. The dried flower is taken orally for diabetes. Hot water of dried fruit is used for piles and externally for skin disease and ulcers. Hot water extract of the entire plant is used as anthelmintic, an insecticide and purgative. Juices of bark Andrographic puniculata, Azadirachta indica, Tinospora cardifolia, are taken orally as a treatment for filariasis. The hot water extract is also taken for fever, diabetes, and as a tonic refridgerant, atheminthic. Leaves due to insecticidal properties are kept with with woolen and other cloths for long time. Leaf juice is given in gonorrhea and leucorrhoea. Leaves applied as poultice to relieve boils, their infusion is used as antiseptic wash to promote the healing of wound and ulcers. A paste of leaves is used to treat wounds, ring worms, eczema and ulcers. Bathing with Neem leaves is beneficial for itching and other skin disease. Leaf juice is used as nasal drop to treat worm infestation in nose. The tender twigs of the tree are used as tooth brush which is believed to keep the body system healthy, the breath and mouth clean and sweet. Seed oil is used in leprosy, syphilis, eczema, chronic ulcers.
The pharmacological hypoglycemic action of Neem has examined in diabetic rats. After 24 hrs treatment, Neem 250mg/kg, reduced glucose (15%), cholesterol (15%), triglycerides (32%). Urea (13%), creatinine (23%) and lipids (15%), Multiples dose study for 15 days also reduced creatinine, urea, lipids, triglycerides and glucose. In glucose tolerance test in diabetic rats with neem extract 250mg/kg demonstrated glucose levels were significantly less compared to the control group. Azadirachta indica significantly reduce glucose levels at 15th day in diabetic rats.
Extracts form young flowers and leaves have strong antioxidant potential. An indicator of oxidative stress, malondialdehyde (MDA) was reduced by 46.0% and 50.6% for flower and leaf-based extracts, respectively, prompting the recommendation to use Neem as a vegetable bitter tonic to promote good health.
In HIV/AIDS patients, a12-week oral administration of acetone water neem extract (IRAB) had a significant influence in vivo on CD4 cells (which HIV reduces) without any adverse effects in the patients. Of the 60 patients who completed treatment, 50 were completely laboratory- test compliant. The mean levels of CD4 cells increased by 159% in 50 patients, which is major increase; the no. of HIV/AIDS significant increases were experienced in body weight (12%), hemoglobin concentration (24%), and lymphocyte differential count (24%).
Neem bark extract reduced human gastric acid hypersecretion, and gastro-esophageal and gastroduodenal ulcers.
A study on Neem has revealed a chemo preventive capability by regressing the hepatocarcinogenesis induced by diethyl Nitrosamine (DEN) / 2 Acetylaminofluorence (AAF) carcinogens on Spraque- Dawly rats.
Neem and seed extracts administerd orally at the beginning of post-implantation stage resulted in pregnancy termination in rodents and primates, without permanent effect.
Antihypertensive and antihypercholesteremic effect:
Administration of aqueous extract of neem along with DOCA salt prevented the development of hypertension in rats. Administration of mature leaf extract decreased serum cholesterol significantly without changing serum protein, protein urea and uric acid levels in rats.
The above collected regarding the use of Azadirachta indica (NEEM) in world is matched with available literature. Recent years, especially of plant origin received much attention as they are well tested for their efficiency and generally believed to be safe for human use. Thorough screening of literature available on Azadirachta indica depicted the fact that it is a popular remedy among the various ethnic groups, Unani, Ayurvedic and traditional practitioners for treatment of ailments. Researchers are exploring the therapeutic potential of this plant as it has more therapeutic properties which are not known.