About: Azadirachta is a(n) research topic. Over the lifetime, 4758 publication(s) have been published within this topic receiving 78237 citation(s). The topic is also known as: Neem.
TL;DR: The rates of reduction of the metal ions by Neem leaf extract are much faster than those observed by us in earlier studies using microorganisms such as fungi, highlighting the possibility that nanoparticle biological synthesis methodologies will achieve rates of synthesis comparable to those of chemical methods.
Abstract: We report on the use of Neem (Azadirachta indica) leaf broth in the extracellular synthesis of pure metallic silver and gold nanoparticles and bimetallic Au/Ag nanoparticles. On treatment of aqueous solutions of silver nitrate and chloroauric acid with Neem leaf extract, the rapid formation of stable silver and gold nanoparticles at high concentrations is observed to occur. The silver and gold nanoparticles are polydisperse, with a large percentage of gold particles exhibiting an interesting flat, platelike morphology. Competitive reduction of Au3+ and Ag+ ions present simultaneously in solution during exposure to Neem leaf extract leads to the synthesis of bimetallic Au core-Ag shell nanoparticles in solution. Transmission electron microscopy revealed that the silver nanoparticles are adsorbed onto the gold nanoparticles, forming a core-shell structure. The rates of reduction of the metal ions by Neem leaf extract are much faster than those observed by us in our earlier studies using microorganisms such as fungi, highlighting the possibility that nanoparticle biological synthesis methodologies will achieve rates of synthesis comparable to those of chemical methods.
TL;DR: Les substances derivees du «neem», efficaces contre les insectes sont examines (influence sur le comportement de fixation, the ponte, the prise de nourriture, the metamorphose, the fecondite, the fitners) ainsi que les capacites potentielles des insecticides extraits du neem pour le controle des insectes nuisibles and leurs effets sur les animaux.
Abstract: Les substances derivees du «neem», efficaces contre les insectes sont examines (influence sur le comportement de fixation, la ponte, la prise de nourriture, la metamorphose, la fecondite, la fitners) ainsi que les capacites potentielles des insecticides extraits du neem pour le controle des insectes nuisibles et leurs effets sur les animaux a sang chaud et sur l'homme
TL;DR: This review gives a bird’s eye view mainly on the biological activities of some of the neem compounds isolated, pharmacological actions ofThe neem extracts, clinical studies and plausible medicinal applications of neem along with their safety evaluation.
Abstract: Neem (Azadirachta indica A. Juss) is perhaps the most useful traditional medicinal plant in India. Each part of the neem tree has some medicinal property and is thus commercially exploitable. During the last five decades, apart from the chemistry of the neem compounds, considerable progress has been achieved regarding the biological activity and medicinal applications of neem. It is now considered as a valuable source of unique natural products for development of medicines against various diseases and also for the development of industrial products. This review gives a bird’s eye view mainly on the biological activities of some of the neem compounds isolated, pharmacological actions of the neem extracts, clinical studies and plausible medicinal applications of neem along with their safety evaluation. MEDICINAL plants are part and parcel of human society to combat diseases, from the dawn of civilization. Azadirachta indica A. Juss (syn. Melia azadirachta) is well known in India and its neighbouring countries for more than 2000 years as one of the most versatile medicinal plants having a wide spectrum of biological activity. A. indica A. Juss and M. azedarach are two closely related species of Meliaceae. The former is popularly known as Indian neem (margosa tree) or Indian lilac, and the latter as the Persian lilac. Neem is an evergreen tree, cultivated in various parts of the Indian subcontinent. Every part of the tree has been used as traditional medicine for household remedy against various human ailments, from antiquity 1–6 . Neem has been extensively used in ayurveda, unani and homoeopathic medicine and has become a cynosure of modern medicine. The sanskrit name of the neem tree is ‘Arishtha’ meaning ‘reliever of sickness’ and hence is considered as ‘Sarbaroganib arini’. The tree is still regarded as ‘village dispensary’ in India. The importance of the 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 7,8
TL;DR: This review brings the reader up to date with both pure and applied research in the field and provides a detailed overview of present thinking into the mode of action of azadirachtin.
Abstract: Research into the insecticidal effects of azadirachtin, a limonoid from the Indian Neem tree, Azadirachta indica, has been ongoing for some 30 years. Its strong antifeedant, insect growth regulatory and reproductive effects are now well understood and documented although its biochemical effects at the cellular level are still unknown. Antiffedancy varies markedly between species with Lepidoptera being particularly sensitive to azadirachtin. The physiological effects on growth, moulting and reproduction are more consistent between species although cuticle or gut may provide barries to bioavailability in some species. The mode of action of azadirachtin lies in (i) effects on deterrent and other chemoreceptors resulting in antifeedancy (ii) effects on ecdysteroid and juvenile hormone titres through a blockage of morphogenetic peptide hormone release (e.g. PTTH; allatotropins) and (iii) direct effects on most other tissues studied resulting in an overall loss of fitness of the insect. The complexity of the molecular structure of azadirachtin has precluded its synthesis for pesticide use although novel synthesis of the parent molecule is now almost complete and research into simpler mimetic substances is ongoing. Applied research has concentrated on a variety of natural formulations from neem seed kernels which contain azadirachtin together with several structurally related molecules. This review brings the reader up to date with both pure and applied research in the field and provides a detailed overview of present thinking into the mode of action of azadirachtin. Wherever possible comparative approaches have been made between species of the effects of pure azadirachtin and areas for future research are indicated.
Abstract: The dye, Methylene Blue, was adsorbed on an adsorbent prepared from mature leaves of the Neem tree (Azadirachta indica). A batch adsorption study was carried out with variable adsorbate concentration, adsorbent amount, pH, and temperature. Ninety-three percent of the dye could be removed by 2 g of the Neem leaf powder from 1 L of an aqueous solution containing 25 mg of the dye at 300 K. The adsorption followed pseudo first order kinetics with a mean rate constant of 3.73 × 10−3 min−1 and an intra-particle diffusion rate constant of 6.36 × 10−2 mg g−1 min−0.5. A possible mechanism of adsorption was suggested on the basis of concurrently operating surface adsorption and pore diffusion. The experimental data yielded excellent fits with Langmuir and Freundlich isotherm equations. The Langmuir monolayer capacity had a mean value of 8.76 mg g−1. The adsorption of the dye was endothermic in nature (ΔH: 4.62–16.74 kJ mol−1) and was accompanied by an increase in entropy (ΔS: 54.22–90.23 J mol−1 K−1) and a decrease in Gibbs energy (ΔG: −10.33 to −13.62 kJ mol−1 in the temperature range of 300–330 K). The results indicated that the dye, Methylene Blue, strongly interacts with a biomass-based adsorbent, the Neem leaf powder.