Neem oil, also known as margosa oil, is a vegetable oil pressed from the fruits and seeds of the neem ( Azadirachta indica ), a tree which is indigenous to the Indian subcontinent and has been introduced to many other areas in the tropics. It is the most important of the commercially available products of neem, and its chemical properties have found widespread use as a pesticide in organic farming.
Azadirachtin is the most well known and studied triterpenoid in neem oil. Nimbin is another triterpenoid which has been credited with some of neem oil's properties as an antiseptic, antifungal, antipyretic and antihistamine. [1]
Neem oil has a history of use in Ayurvedic folk medicine. [2] [3]
The ingestion of neem oil is potentially toxic and can cause metabolic acidosis, seizures, kidney failure, encephalopathy and severe brain ischemia in infants and young children. [2] [4] [5] Neem oil should not be consumed alone without any other solutions, particularly by pregnant women, women trying to conceive or children. [2] It can also be associated with allergic contact dermatitis. [6]
Recently, neem oil has been utilized to prepare various polymeric resins. These resins are used to formulate different types of polyurethane coatings. [7] [8]
Formulations that include neem oil have found wide usage as a biopesticide for horticulturists [9] and for organic farming, as it repels a wide variety of insect pests including mealy bugs, beet armyworms, aphids, cabbage worms, thrips, whiteflies, mites, fungus gnats, beetles, moth larvae, mushroom flies, leaf miners, caterpillars, locusts, nematodes and Japanese beetles. [10] [11]
When sufficiently dilute and not concentrated directly into their area of habitat or on their food source, neem oil is not known to be harmful to mammals, birds, earthworms or some beneficial insects such as butterflies, honeybees and ladybugs. It can be used as a household pesticide for ants, bedbugs, cockroaches, houseflies, sand flies, snails, termites and mosquitoes both as a repellent and as a larvicide. [3]
Neem extracts act as an antifeedant and block the action of the insect molting hormone ecdysone. Azadirachtin is the most active of these growth regulators (limonoids), occurring at 0.2–0.4% in the seeds of the neem tree. [12]
Azadirachta indica, commonly known as neem, margosa, nimtree or Indian lilac, is a tree in the mahogany family Meliaceae. It is one of two species in the genus Azadirachta. It is native to the Indian subcontinent and to parts of Southeast Asia, but is naturalized and grown around the world in tropical and subtropical areas. Its fruits and seeds are the source of neem oil. Nim is a Hindustani noun derived from Sanskrit nimba (निंब).
A mango is an edible stone fruit produced by the tropical tree Mangifera indica. It originated from the region between northwestern Myanmar, Bangladesh, and northeastern India. M. indica has been cultivated in South and Southeast Asia since ancient times resulting in two types of modern mango cultivars: the "Indian type" and the "Southeast Asian type". Other species in the genus Mangifera also produce edible fruits that are also called "mangoes", the majority of which are found in the Malesian ecoregion.
Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. Acaricides, which kill mites and ticks, are not strictly insecticides, but are usually classified together with insecticides. The major use of Insecticides is agriculture, but they are also used in home and garden, industrial buildings, vector control and control of insect parasites of animals and humans. Insecticides are claimed to be a major factor behind the increase in the 20th-century's agricultural productivity. Nearly all insecticides have the potential to significantly alter ecosystems; many are toxic to humans and/or animals; some become concentrated as they spread along the food chain.
Varnish is a clear transparent hard protective coating or film. It is not to be confused with wood stain. It usually has a yellowish shade due to the manufacturing process and materials used, but it may also be pigmented as desired. It is sold commercially in various shades.
Azadirachtin, a chemical compound belonging to the limonoid group, is a secondary metabolite present in neem seeds. It is a highly oxidized tetranortriterpenoid which boasts a plethora of oxygen-bearing functional groups, including an enol ether, acetal, hemiacetal, tetra-substituted epoxide and a variety of carboxylic esters.
An essential oil is a concentrated hydrophobic liquid containing volatile chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the oil of the plant from which they were extracted, such as oil of clove. An essential oil is essential in the sense that it contains the essence of the plant's fragrance—the characteristic fragrance of the plant from which it is derived. The term "essential" used here does not mean indispensable or usable by the human body, as with the terms essential amino acid or essential fatty acid, which are so called because they are nutritionally required by a living organism.
N,N-Diethyl-meta-toluamide, also called diethyltoluamide or DEET, is the oldest, most effective and most common active ingredient in commercial insect repellents. It is a slightly yellow oil intended to be applied to the skin or to clothing and provides protection against mosquitoes, flies, ticks, fleas, chiggers, leeches, and many other biting insects.
The tetranortriterpenoid class of naturally occurring organic compounds, of which the most noted compound is azadirachtin, extracted from the neem tree that displays insecticidal properties. Azadirachtin mimics insect hormones called ecdysones that regulate the pupation of insects; application of azadirachtin interrupts the development and pupation of insects, eventually killing them.
Smart materials, also called intelligent or responsive materials, are designed materials that have one or more properties that can be significantly changed in a controlled fashion by external stimuli, such as stress, moisture, electric or magnetic fields, light, temperature, pH, or chemical compounds. Smart materials are the basis of many applications, including sensors and actuators, or artificial muscles, particularly as electroactive polymers (EAPs).
Microencapsulation is a process in which tiny particles or droplets are surrounded by a coating to give small capsules, with useful properties. In general, it is used to incorporate food ingredients, enzymes, cells or other materials on a micro metric scale. Microencapsulation can also be used to enclose solids, liquids, or gases inside a micrometric wall made of hard or soft soluble film, in order to reduce dosing frequency and prevent the degradation of pharmaceuticals.
An insect repellent is a substance applied to the skin, clothing, or other surfaces to discourage insects from landing or climbing on that surface. Insect repellents help prevent and control the outbreak of insect-borne diseases such as malaria, Lyme disease, dengue fever, bubonic plague, river blindness, and West Nile fever. Pest animals commonly serving as vectors for disease include insects such as flea, fly, and mosquito; and ticks (arachnids).
Azadirachta is a genus of two species of trees in the mahogany family Meliaceae. Numerous species have been proposed for the genus but only two are currently recognized, Azadirachta excelsa and the economically important tree Azadirachta indica, the neem tree, from which neem oil is extracted. Both species are native to the Indomalaysian region, and A. indica is also widely cultivated and naturalized outside its native range.
Icaridin, also known as picaridin, is an insect repellent which can be used directly on skin or clothing. It has broad efficacy against various arthropods such as mosquitos, ticks, gnats, flies and fleas, and is almost colorless and odorless. A study performed in 2010 showed that picaridin spray and cream at the 20% concentration provided 12 hours of protection against ticks. Unlike DEET, icaridin does not dissolve plastics, synthetics or sealants, is odorless and non-greasy and presents a lower risk of toxicity when used with sunscreen, as it may reduce skin absorption of both compounds.
Neem cake organic manure is the by-product obtained in the process of cold pressing of neem tree fruits and kernels, and the solvent extraction process for neem oil cake. It is a potential source of organic manure under the Bureau of Indian Standards, Specification No. 8558. Neem has demonstrated considerable potential as a fertilizer. For this purpose, neem cake and neem leaves are especially promising. Puri (1999), in his book Neem : The Divine Tree Azadirachta, has given details about neem seed cake as manure and nitrification inhibitor. The author has described that, after processing, neem cake can be used for partial replacement of poultry and cattle feed.
A larvicide is an insecticide that is specifically targeted against the larval life stage of an insect. Their most common use is against mosquitoes. Larvicides may be contact poisons, stomach poisons, growth regulators, or (increasingly) biological control agents.
p-Menthane-3,8-diol, also known as para-menthane-3,8-diol, PMD, or menthoglycol, is an organic compound classified as a diol and a terpenoid. It is colorless. Its name reflects the hydrocarbon backbone, which is that of p-menthane. A total of eight stereoisomers are possible, based on the three stereocenters of the ring. Depending on the source, one or more may predominate.
Ethyl butylacetylaminopropionate is an insect repellent whose trade name is IR3535 and was developed and commercialized by Merck KGaA (Germany). It is a colorless and odorless oil with a good skin feel in final products, and it is biodegradable.
Nimbin is a triterpenoid isolated from Neem. Nimbin is thought to be responsible for much of the biological activities of neem oil, and is reported to have anti-inflammatory, antipyretic, fungicidal, antihistamine and antiseptic properties.
Carapa guianensis is a species of tree in the family Meliaceae, also known by the common names andiroba or crabwood.
Azadiradione is a naturally occurring compound found in several plants, most notably the neem tree. It is a tetracyclic triterpenoid.