Azadirachta indica

Azadirachta indica is also called as Neem,Neem is a tree in the mahogany family Meliaceae. It is native to India, Myanmar, Bangladesh, Sri Lanka, Malaysia and Pakistan. It grows in tropical and semi-tropical regions. It was also the state tree of Hyderabad Deccan.

Neem is a fast-growing tree in the world that can reach up to 15–20 m (about 50–65 feet) tall, and sometimes even to 35–40 m (115–131 feet). It is evergreen

Uses

Products made from neem have been used in India for over two millennia for their medicinal properties. They are said to be antifungal, antidiabantibacterial, antiviral, contraceptive and sedative. Neem products are also used in selectively controlling pests in plants. Neem is considered a part of Ayurvedic medicine.

Neem is also known as the' village pharmacy'

All parts of neem are used for preparing many different medicines, especially for skin disease.[4]

Part of the Neem tree can be used as a spermicide .
Neem oil is used for preparing cosmetics (soap and shampoo, as well as lotions and others), and is useful for skin care such as acnetreatment. Neem oil has been used effectively as a mosquito repellent.
Neem is useful for damaging over 500 types of insects, mites, ticks, and nematodes, by changing the way they grow and act. Neem does not normally kill pests right away, rather it slows their growth and drives them away. As neem products are cheap and not poisonous to animals and friendly insects, they are good for pest control

In the UK, plant protection products that contain azadirachtin, the active ingredient of neem oil, are illegal

Medicinal properties of Neem

For thousands of years the beneficial properties of Neem (Azadirachta indica A. Juss) have been recognized in the Indian tradition. Each part of the neem tree has some medicinal property. Biswas et al (2002) have recently reviewed the biological activities some of the neem compounds, pharmacological actions of the neem extracts, clinical study and plausible medicinal applications of neem along with their safety evaluation.

Neem has two closely related species: A. indica A. Juss and M. azedarac, the former is popularly known as Indian neem (margosa tree) or Indian lilac, and the other as the Persian lilac. Neem has been extensively used in ayurveda, unani and homoeopathic medicine.The Sanskrit name of neem tree is Arishtha meaning 'reliever of sickness' and hence is considered as Sarbaroganibarini. The tree is still regarded as 'village dispensary' in India. The importance of the neem tree has been recognized by US National Academy of Sciences, which published a report in 1992 entitled 'Neem – a tree for solving global problems'.

More than 135 compounds have been isolated from different parts of neem and several reviews have also been published on the chemistry and structural diversity of these compounds. The compounds have been divided into two major classes: isoprenoids (like diterpenoids and triterpenoids containing protomeliacins, limonoids, azadirone and its derivatives, gedunin and its derivatives, vilasinin type of compounds and C- secomeliacins such as nimbin, salanin and azadirachtin ) and non-isoprenoids, which are proteins (amino acids) and carbohydrates (polysaccharides), sulphurous compounds, polyphenolics such as flavonoids and their glycosides, dihydrochalcone, coumarin and tannins, aliphatic compounds, etc.

Biological activity of some Neem compounds

Nimbidin, a major crude bitter principle extracted from the oil of seed kernels of A. indica demonstrated several biological activities. From this crude principle some tetranortriterpenes, including nimbin, nimbinin, nimbidinin, nimbolide and nimbidic acid have been isolated.

Biological activity of Neem compounds

Anti-inflammatory; Antiarthritic; Antipyretic; Hypoglycaemic; Antigastric ulcer; Spermicidal; Antifungal; Antibacterial; Diuretic; Antimalarial; Antitumour; Immunomodulatory etc.

Medicinal Uses

Various parts of the neem tree have been used as traditional Ayurvedic medicine in India. Neem oil and the bark and leaf extracts have been therapeutically used as folk medicine to control leprosy, intestinal helminthiasis, respiratory disorders, constipation and also as a general health promoter. Its use for the treatment of rheumatism, chronic syphilitic sores and indolent ulcer has also been evident. Neem oil finds use to control various skin infections. Bark, leaf, root, flower and fruit together cure blood morbidity, biliary afflictions, itching, skin ulcers, burning sensations and pthysis

Immunostimulant activity

The aqueous extract of neem bark and leaf also possesses anticomplement and immunostimulant activity. Neem oil has been shown to possess activity by selectively activating the cell-mediated immune mechanisms to elicit an enhanced response to subsequent mitogenic or antigenic challenge.

Hypoglycaemic activity

Aqueous extract of neem leaves significantly decreases blood sugar level and prevents adrenaline as well as glucose-induced hyperglycaemia. Recently, hypoglycaemic effect was observed with leaf extract and seed oil, in normal as well as alloxan-induced diabetic rabbits.

Antiulcer effect

Neem leaf and bark aqueous extracts produce highly potent antiacid secretory and antiulcer activity.

Antifertility effect

Intra-vaginal application of neem oil, prior to coitus, can prevent pregnancy. It could be a novel method of contraception.

Antimalarial activity

Neem seed and leaf extracts are effective against both choroquin-resistant and sensitive strain malarial parasites.

Antifungal activity

Extracts of neem leaf, neem oil seed kernels are effective against certain fungi including Trichophyton, Epidermophyton, Microspor Trichosporon, Geotricum and Candida.

Antibacterial activity

Oil from the leaves, seed and bark possesses a wide spectrum of antibacterial action against Gram-negative and Gram-positive microorganisms, including M. tuberculosis and streptomycin resistant strains. In vitro, it inhibits Vibrio cholerae Klebsiella pneumoniae, M. tuberculosis and M. pyogenes. Antimicrobial effects of neem extract have been demonstrated against Streptococcus mutans and S. faecalis.

Antiviral activity

Aqueous leaf extract offers antiviral activity against Vaccinia virus, Chikungemya and measles virus.

Anticancer activity

Neem leaf aqueous extract effectively suppresses oral squamous cell carcinoma induced by 7, 12-dimethylbenz[a] anthracene (DMBA), as revealed by reduced incidence of neoplasm. Neem may exert its chemopreventive effect in the oral mucosa by modulation of glutathione and its metabolizing enzymes.

Antioxidant activity

The antioxidant activity of neem seed extract has been demonstrated in vivo during horse- grain germination.

Effect on central nervous system

Varying degrees of central nervous system (CNS) depressant activity in mice was observed with the leaf extract. Fractions of acetone extract of leaf showed significant CNS depressant activity.

Possible medicinal applications of neem

Neem extract Its effective to cure ringworm, eczema and scabies. Lotion derived from neem leaf, when locally applied, can cure these dermatological diseases within 3-4 days in acute stage or a fortnight in chronic case. A paste prepared with neem and turmeric was found to be effective in the treatment of scabies in nearly 814 people100.

Neem leaf extract has been prescribed for oral use for the treatment of malaria by Indian ayurvedic practitioners from time immemorial. Recently, a clinical trial has been carried out to see the efficacy of neem extract to control hyperlipidemia in a group of malarial patients severely infected with P. falciparum. The lipid level, especially cholesterol, was found to be lower during therapy when compared to non-malaria patients. Reports are available regarding the use of neem to treat patients suffering from various forms of cancer. One patient with parotid tumour and another with epidermoid carcinoma have responded successfully when treated with neem seed oi1.

NIM- 76, a refined product from neem oil, was studied in 10 human volunteers, where intra-vaginal application before sexual intercourse could prevent pregnancy with no adverse effect on vagina, cervix and uterus. The data suggested that intrauterine treatment is safe.

Safety evaluation with various parts of neem and neem products

Various studies have been reported on the safety evaluation of different parts of neem as well as its various biologically active products.

Nimbidin produces sub-acute toxicity in adult rats after daily administration of 25, 50 or 100 mg/kg for six weeks. A significant hypoglycaemic effect was observed by feeding nimbidin to fasting rabbits. Nimbidin also has spermicidal activity. Nimbolide, a major chemical component of neem seed oil, and nimbic acid were found to be toxic to mice when given intravenously or intraperitoneally. They are, however, less toxic to rats and hamster. Nimbolide and nimbic acid at a lethal dose cause death in most animals by dysfunction of kidney, small intestine and liver as well as by marked and sudden drop of arterial blood pressure.

Conclusion

It is heartening to see that a traditional Indian plant medicine has now led to several therapeutically and industrially useful preparations and compounds, which generates enough encouragement among the scientists in exploring more information about this medicinal plant. As the global scenario is now changing towards the use of nontoxic plant products having traditional medicinal use, development of modem drugs from neem should be emphasized for the control of various diseases. In fact, time has come to make good use of centuries-old knowledge on neem through modern approaches of drug development. For the last few years, there has been an increasing trend and awareness in neem research. Quite a significant amount of research has already been carried out during the past few decades in exploring the chemistry of different parts of neem. An extensive research and development work should be undertaken on neem and its products for their better economic and therapeutic utilization.

Neem Oil

Neem oil is a naturally occurring pesticide found in seeds from the neem tree. It is yellow to brown, has a bitter taste, and a garlic/sulfur smell. While it doesn’t sound very attractive, neem oil can be very beneficial by providing an all-natural pesticide that controls both pests and diseases.

Loaded with nutrients, neem oil is also used in natural skin care products because it contains high levels of antioxidants that help protect the skin from environmental damage. Neem also helps fight free radical damage in the skin because it contains carotenoids, which provide high antioxidant compounds. As a result, cold-pressed neem oil and neem extracts are widely used in cosmetics such as soap, hair products, cosmetics, hand creams and pet shampoos.

Neem oil is usually comprised of a mixture of components. Azadirachtin is the most active component and is used for for repelling and killing pests.After the extraction of azadirachtin, the portion left over is called clarified hydrophobic neem oil. As reported by Current Science, it works as an effective non-toxic insect control agent to agriculture.

Since neem is also especially high in important fatty acids and vitamin E and can quickly penetrate outer layers of skin, it is extremely effective in healing dry and damaged skin.

4 Benefits of Neem Oil

1. Combats Bed Bugs

The Environmental Protection Agency has reported that neem oil, when combined with with certain approved agents, can be safe and effective against bed bugs both at home and in commercial environments. Performance trials conducted show that neem oil helps control bed bug adults, nymphs and eggs.

The EPA issued registrations for two new products: TER-TRU1, containing 5.5 percent cold-pressed neem oil, is a ready-to-use formulation for spot treatment by residential and commercial users; TER-CX1, containing 22.0 percent cold-pressed neem oil, is a concentrate formulation for commercial use in the treatment of whole rooms.

2. Serves as a Natural Insecticide

Neem is considered a safe, naturally occurring insecticide. The Journal of Insect Science notes that

… control programs using conventional insecticides to target anthropogenic mosquito habitats are very expensive because these habitats are widespread, particularly in cities of most African countries. Additionally, there are serious environmental concerns regarding large-scale application of most conventional insecticides. Clearly there is a need for alternative methods that are more effective, less expensive, and environmentally friendly. One such method would be the application of preparations made from parts of the neem tree, Azadirachta indica A. Jussieu (Sapindales: Meliaceae).

Azadirachtin is the important ingredient in neem oil that can help prevent unwanted pests from destroying plants. While there are other ingredients in neem oil spray that show insecticidal properties, azadirachtin is responsible for 90 percent of the effect of neem oil insecticide.

EPA modeling of potential residues of neem oil following terrestrial treatments indicated that residues declined rapidly between applications and following the final application. Neem products do not provide absolute insect control; however, frequent applications can reduce pest populations dramatically by repelling them and inhibiting their larval development, growth, fertility, mating and egg laying, and deterring feeding.

How does it work? A solution of neem oil smothers insect pests and has antifungal properties as well. The oil coats the plant’s surface and prevents the germination of fungal spores. Neem oil can also be used as a safe, natural leaf polish, though some plants may be sensitive. It is always best to test first.

The American Orchid Society also reports that neem has been shown to ward off sand flies and mosquitoes, aiding in control of the spread of diseases such as malaria. It has been used to treat lice and scabies, and tea brewed from the leaf of the tree has been used for termite control. Neem, in the form of leaves, can be placed in the pockets of woolen clothing to fend off moths and added to stored grains and beans to help keep insects out.

Neem products are often used as a cattle-feed supplement to kill parasites. Because neem is relatively inexpensive, it’s even has been helpful to reduce post-harvest losses in developing countries.

3. Offers Wide-Ranging Skin Care — Smoothes Wrinkles, Stimulates Collagen, Relieves Dry Skin & Reduces Eczema and Acne

The Department of Biochemistry and Biotechnology at Kwame Nkrumah University of Science and Technology (KNUST) states that neem oil is rich in essential fatty acids (EFAs), triglycerides, vitamin E and calcium. Because of its EFAs and vitamin E, neem oil penetrates deep within the skin to heal the miniscule cracks brought on by severe dryness. Fatty acids present in the neem kernel oil are oleic acid (52.8 percent), linoleic acid (2.1 percent), palmitic acid (12.6 percent) and stearic acid (21.4 percent).

The fatty acids and vitamin E found in neem oil are easily absorbed into the skin without leaving the skin greasy. Once absorbed, these powerful properties work to rejuvenate the skin’s cells and restore elasticity. Benefit-rich vitamin E acts as a free radical scavenger, by hindering the oxidizing processes in the skin. It promotes soft and supple skin, helps in reducing old scars and promotes healing.

Need also stimulates collagen production, good for aging skin. Indeed, if used regularly, neem may help smooth wrinkles and fine lines while helping to prevent the signs of aging. Neem oil may prove to be a natural remedy for eczema symptoms — including dry, red, itchy skin — and be very soothing, but it will not cure the root causes for eczema.

There are anti-inflammatory compounds known as nimbidin and nimbin that help relieve swelling and redness. another compound known as quercetin supports the body’s ability to respond to inflammation by inhibiting both the manufacture and release of histamine and other irritants.

KNUST also states that neem oil, when used as a soap, is antimicrobial and helps people suffering from skin diseases such as acne because it can help to soothe irritation and inflammation by removing bacteria from the surface of the skin; therefore, preventing more break-outs.

Neem oil has been used in traditional folk medicine and as a home remedy for acne because of the aspirin-like compound that helps rid the skin of bacteria. It also helps reduce redness and inflammation. The high fatty-acid content in neem oil is said to prevent and treat scars from acne and is non-comedogenic. The leaves are also an excellent exfoliant that can be used in a facial mask to pull out impurities and tighten pores.

4. Mosquito Repellent

Neem oil makes for a great natural mosquito repellent that is safe to use. As reported in the Journal of the American Mosquito Control Association, when 2 percent neem oil was mixed with coconut oil, then applied to the exposed body parts of human volunteers, it provided complete protection for approximately 12 hours from the bites of all anopheline species. They claim that the application of neem oil is safe and can even be used for protection from malaria in endemic countries.

How to Buy & Use Neem Oil

It is important that you read labels carefully before making a purchase since many pre-mixed versions have been refined. You want it to be yellow in color, cloudy, and have an odor similar to garlic and sulfur. Look for 100 percent pure neem oil. It’s also helpful to use organic neem oil because this ensures that it’s not contaminated with solvents or petrochemicals that may have been used in the purification process.

Commercial neem oil sprays often contain a refined neem oil extract, usually smell better and are ready to use; however, making your own is much more efficient and costs less. This is more important because neem oil extract has a lower concentration of azadirachtin, and azadirachtin is the ingredient that affects insects.

If we are talking about a pesticide, just how safe is it then? Neem is considered harmless to humans, animals, birds, beneficial insects and earthworms, and has been approved by the U.S. Environmental Protection Agency for use on food crops and bed bugs. Azadirachtin and other active ingredients in the neem seed have insecticidal properties that are effective against a broad spectrum of insects, many mites and nematodes, and even snails and fungi, and do not seem to generate resistance in the pests they affect.

Regarding plants, The American Orchid Association tell us that oil solutions should never be applied to plants during hot weather (85° F [29° C] or warmer) or in direct sunlight. To prevent burning of tissues, treated plants should be shaded until the application is dry. Avoid strong or excessive amounts of detergent or use of ammonia-based cleaners, as these may damage your plants.

Store your neem oil in the refrigerator, or in an area that is cool and dark so that it will keep longer. It should keep for a year or two. Make sure you label it appropriately wherever you choose to store it. However, neem oil can solidify at low temperatures. You can simply place the container in warm water to get it back to a liquid form for use, but make sure it doesn’t get too warm, (85 degrees F/30 degrees C or lower), since heat destroys the azadirachtin (the most effective component).

Because neem oil does not mix with water, you will need to add an emulsifier such as a small amount of soap, detergent or shampoo. While you could use any liquid soap, it’s safest to use a proper insecticidal soap that will not hurt plants. Household soaps may burn or harm sensitive plants.

The EPA also reports that based on the data available, it has been determined that there are no unreasonable adverse effects to the U.S. population and the environment when label instructions are followed and good agricultural practices are employed. Laboratory studies indicate that the active ingredient is not toxic following oral, inhalation or dermal exposure.

The most likely human exposure to cold-pressed neem oil will occur via dietary consumption to treated fruits, seeds or leafy vegetables.

History and Interesting Facts

The neem tree, Azadirachta indica, (also known as Indian lilac or margosa), is thought to have originated in India or Burma. Neem is a large, fast-growing evergreen that can reach approximately 40 to 80 feet in height. It is drought resistant, heat tolerant and may live up to 200 years! It grows in many Asian countries as well as tropical areas of the Western hemisphere. Neem oil, which is extracted from the tree’s seeds, has been used for its medicinal and insecticidal properties for more than 4,000 years.

The bark, leaves and seeds are used to make medicine. Less frequently, the root, flower and fruit are also used. The leaves are generally available year-round as the tree is evergreen except during severe droughts or if exposed to frost.

The major active constituents in neem are terpenoids, such as azadirachtin, which are considered to be antimicrobial acting as an insect repellant among many other actions. People in the tropics sometimes chew neem twigs instead of using toothbrushes, but this can cause illness; neem twigs are often contaminated with fungi within two weeks of harvest and should be avoided.

The EPA goes on to explain that cold-pressed neem oil is a mixture of several C26 terpenoids that are naturally occurring organic compounds. Azadirachtin, the most common terpenoid in cold-pressed neem oil, is a federally registered active ingredient pesticide. Cold-pressed neem oil also contains steroids, fatty acids and a number of essential oils that are commonly found in a normal diet. These substances are generally recognized as safe (GRAS) by the United States Food and Drug Administration.

Neem Oil Recipes

Neem Oil Wrinkle Cream With Lavender

Ingredients:

½ ounce of pure, organic neem oil
8 ounces of organic jojoba oil
4–5 drops pure lavender oil

Directions:

Place ingredients in a cosmetic container or small cosmetic bottle. Mix or shake well. Make sure all ingredients are well blended. Apply, as a moisturizer, to your to skin liberally.

For skin problems, apply directly onto the skin two or three times a day.

You should not use undiluted neem oil on your skin. Always try a very small amount on a small area of skin to make sure your skin does not have a negative reaction.

Neem Oil Foliar Spray Solution (from the American Orchid Society and suggested by growers)

Ingredients:

1 teaspoon neem oil
½ teaspoon plant-safe liquid soap
1 quart warm water

Directions:

Place in a plastic spray bottle and make sure to mix all ingredients well, shaking intermittently to ensure they remain well mixed.

Because the oil smothers insect pests, be sure to completely cover all plant surfaces for maximum effectiveness. Some sources indicate that the mixture begins to break down after eight hours, so a fresh batch should be used at every application.

The insect-controlling properties of neem lose effectiveness over time, especially in warmer temperatures, and may be washed off during watering or by rainfall, so repeat sprayings at weekly to biweekly intervals are needed to control successive generations of pests. In addition, it is useful to keep up manual removal of bugs as part of the control regime.

Risks and Side Effects

It is important to consider the appropriate dose of neem based on the user’s age, health, and any other conditions. There is not enough scientific information to determine an appropriate range of doses for neem at this time; however, keep in mind that you should always consult your doctor before using any natural products, especially children, pregnant women and nursing mothers. Be sure to follow relevant directions on product labels.

While neem leaf extracts appear to be safe, it is possible that unknown interactions exist. If you take medication, always discuss the potential risks and benefits of adding a new supplement with your doctor or pharmacist.