| General
info
A tree belonging to
the mahogany family known as the "free tree" because of its
ability to "free the soil." Popular in the Philippines, more
for its insecticidal properties (pang-lamok) than for its medicinal
applications. In India, it is considered the most useful traditional
medicinal plant, and commercially beneficial as each part of the tree
has some medicinal property.
Botany
Neem is a medium-sized tree
growing to 15 meters high, with wide spreading branches forming an
oval crown. Leaves are pinnately compound. The drooping leaflets are
1 centimeter long, paired, lanceolate, acuminate with serrated margins. The
blade is shiny dark green on the upper surface and pale green on the
underside. Flowers are numerous, small, white and fragrant.
 Distribution
- Not widespread in
the Philippines.
- A good shade tree.
- Propagated by seeds
- Spread by bats.
- Probably a native of Burma.
- Cultivated from India to Indonesia.
Constituents
• From the seed
is produced a bitter fixed oil, nimbidin, known as
"Oil of Margosa" or neem oil.
• Neem seeds yield a fix oil of glycerides and bitter compounds
including nimbin, nimbinin and nimbidol.
• Neem bark and leaves contain tannin and oil.
• Azadirachtin, the insecticide constituent of the seeds, is
biodegradable, non-mutagenic, and nontoxic to birds, fish, and warm-blooded
animals. The EPA has approved a neem formulation (Margosan-O) as a pesticide
for limited use on nonfood crops
• Antiinflammatory (nimbidin, sodium nimbidate, gallic acid, catechin,
polysaccharides).
• Antiarthritic, hypoglycemic, antipyretic, hypoglycemic, diuretic,
anti-gastric ulcer (nimbidin)
• Antifungal (nimbidin, gedunin, cyclic trisulfide)
• Antibacterial (nimbidin, nimbolide, mahmoodin, margolone, margolonone,
isomargolonone)
• Spermicidal (nimbin, nimbidin)
• Antimalarial (nimbolidfe, gedunin, azadirachtin)
• Antitumor (polysaccharides)
• Immunomodulatory (NB-II peptoglycan, gallic acid, epicatechin,
catechin)
• Hepatoprotective (aqueous extract of neem leaf)
• Antioxidant (neem seed extract)
Properties
• Considered antibacterial, hypoglycemic, antiulcer, antifertility, spermicidal, anti-malarial, antitumor, immunomodulatory, hepatoprotective, antioxidant, antifungal, anti-inflammatory.
Parts
used
Whole plant.
.
Uses
Edibility
- Leaves and flowers are edible.
Folkloric
- Poultice of leaves for
swollen glands, bruises and sprains.
- Fresh leaf-tea used for malaria.
- Tree and root barks have been used for malaria, jaundice, and for intestinal
parasitism.
- Edible pulp of the fruit used for hemorrhoids.
- Used for scabies and many other skin diseases.
- When soaked in water, used for bathing and as postcoital contraceptive.
- Spermicide made from plant sold in India.
Ayurvedic medicine
• Leaf- leprosy, intestinal parasites, eye problems, skin ulcers
• Bark - pain and fever.
• Flower - bile suppression, intestinal worms and phlegm.
• Fruit - piles, intestinal worms, urinary disorder, nose bleeding , phlegm,
eye problem, diabetes, wounds and leprosy.
• Twig - cough, asthma, piles, intestinal worms, spermatorrhoea, urinary
disorders, diabetes.
• Gum - ringworm, scabies, wounds and ulcers.
• Seed pulp and oil- leprosy and intestinal worms.
• Neem oil may be useful for gingivitis.
• Oil used intravaginally for spermicidal and contraceptive properties.
Others
- Toothbrush: Young tender branches
are chewed for toothbrushing use.
- Toothpaste: Extracts used in the manufacture of toothpaste for its antibacterial property.
- Insecticide: Leaves and seeds are sources of powerful insecticide Azadirachtin. Leaf's oil is used as a local antiseptic and insecticide.
- Repellent: In the rural areas, burning of leaves and seeds used as mosquito repellant. Fresh seed oil has a strong garlic odor and used as ingredient for insect sprays.
- Timber: Wood used as mahogany substitute.
Studies
• Lipid
Effects / Antiviral: Effect of Supplemental Garlic and
Neem Leaves in Broiler Feeds on Blood Cholesterol, Triglycerides and
Antibody Titer: Study showed
neem had greater potential than garlic in reducing cholesterol, triglycerides
and increasing the antibody titers against viruses.
• Antibacterial / Anticariogenic: Study showed Neem bark constituents have the ability to suppress growth of cariogenic bacteria (Streptococcus sobrinus).
• Anti-ulcer: (1) Mechanism
of antiulcer effect of Neem (Azadirachta indica) leaf extract: effect
on H+-K+-ATPase, oxidative damage and apoptosis: Study suggests antiulcer
activity is achieved by blocking acid secretion through inhibition
of H+K+ATPase and preventing oxidative damage and apoptosis. (2) Study of A indica in albino rats showed significant inhibition of basal and histamine-induced gastric acid secretion. Cimetidine seemed to augment AI inhibition of gastric acid secretion. (3) Study of neem bark extract showed therapeutic potential in controlling gastric hypersecretion and gastroesophageal and gastroduodenal ulcers. (4) Study showed neem extract to have a regenerative potential in ethanol-induced mucosal damage in the stomach and ileum and may be adopted in the management of gastrointestinal ulcer disorders.
• Anti-candidal:
Anticandidal activity of Azadirachta indica: Study suggested hexane
and alcoholic extracts to have anticandidal potential.
• Antiplaque Activity: A study was done on the effectiveness of neem leaf extract against plaque formation. Results showed the dental gel containing neem extract significantly reduced the plaque index and bacterial count of S mutans and Lactobacillus species compared with commercial chlorhexidine gluconate mouthwash as control.
• Antidermatophytic Activity: A study showed the neem seed extract has high antidermatophytic properties and supports the alternative use of neem oil in the treatment of various skin infections.
• Biosorbent Activity: A study showed the effectiveness of the Neem leaf powder as a biosorbent for removing dyes like Congo Red from water.
• Hypoglycemic / Antidiabetic Activity: (1) In a study of 30 known or less known hypoglycemic medicinal plants in folk medicine, Azadirachta indica was one of 24 samples (18th or 24) that was observed to have significant blood glucose lowering activities. (2) Study on the aqueous extracts of C roseus, Azadirachta indica and A sativum indicated significant antidiabetic activity, supporting its traditional use in Ayurveda for therapy of diabetes.
• Hepatoprotective Activity: (1) A study showed A indica leaf extract showed hepatoprotective effects against paracetamol-induced hepatic damage probably through its antioxidant activity. (2) Leaf extract inhibited paracetamol induced damage. Results show A. indica offer protection to hepatocytes against paracetamol-induced hepatotoxicity in wistar rats.
• Anti-Fertility Activity / Rodent Control: A study showed Neem seed extract can be used as an anti-fertility agent on baits to control harmful agricultural rodents.
• Hypoglycemic: Study of leaf extract and seed oil showed a hypoglycemic effect in alloxan-induced diabetic rabbits. Pretreatment with A. indica leaf extract or seed oil partially prevented the blood glucose rise.
• Chemopreventive: In a study evaluating the anticarcinogenic potential of A. indica against N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis. Results showed A. indica may have anticancer potential against NDEA-induced hepatic cancer. There was significant reduction in tumor incidence, tumor multiplicity, and increase in survival.
• Apoptosis Induction: Induction of apoptosis if one of the active strategies to arrest cancer cell proliferation. Study of an ethanolic leaf extract showed chemopreventive effects probably mediated by induction of apoptosis.
• Larvicidal / Antimalarial: Study showed neem oil has good larvicidal properties for Anopheles gambiae and suppresses adult emergence. It presents as a readily available and inexpensive alternative to conventional larvicides.
• Antifungal / Postharvest Fruit Disease: Study showed neem seed kernel extract on post harvest diseases showed significant reduction of four pathogens.
• Natural Insecticide / Leaves / Azadirachtin: Azadirachtin, a liminoid from the Neem tree, has long been known for its strong antifeedant, insect growth regulatory and reproductive effects. Antifeedancy varies and mosquitoes are particularly sensitive. Study provides a detailed overview on azadirachtin. A prepared neem insecticide recorded mosquito bites after an hour, an efficiency of 100%. The efficiency decreased to 84.5% to 85% after one and a half to two hours.
• Hypolipidemic Effects: Study in streptozotocin-induced diabetic rats showed A. indica leaf extract significant reduced the total cholesterol, LDL, and VLDL cholesterol, and triglycerides. HDL-cholesterol remained unchanged.
• Quinone Reductase Inhibitor / Nimbolide: Nimbolide, a limonoid, and chlorophylls isolated from a chloroform extract showed the strongest QR inducing capacity among 4 extracts of neem flowers. Results suggest nimbolide and chlorophylls may be chemopreventive potential.
• Chemoprevention / Favorable Hematologic Parameters: Study in benzo(a)pyrene-induced murine forestomach tumorigenesis bioassay protocol showed favorable effects on hematological parameters with significant effect on overall well being, tumorigenesis and chemoprevention.
Toxicity Studies
• Acute Toxicity Study of Neem Oil: Study of neem oil by oral route in rats and rabbits showed dose-related pharmacotoxic symptoms along with biochemical and histopathological indices of toxicity, with the changes in the lungs and CNS as target organs of toxicity.
Availability
Wildcrafted.
Available in cybermarkets as supplements, oil, cakes, extracts, and
organic manure.
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