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Showing papers on "Azadirachta published in 2009"


Journal ArticleDOI
TL;DR: The adsorption of dye on neem sawdust was found to follow a gradual process and the dimensionless factor, R(L) of the malachite green, neemsawdust isotherm revealed that the adsorptive process is favourable in nature.

434 citations


Journal ArticleDOI
TL;DR: There is an untapped resource of endophytic microorganisms that could be exploited in the biotechnological, medicinal, and agricultural industries and shown to have broad spectrum significant antimicrobial activity, while about 4% of them showed strong and acute inhibition to pathogenic fungi and bacteria.
Abstract: Endophytic actinomycetes from Azadirachta indica A. Juss. were screened and evaluated for their anti-microbial activity against an array of pathogenic fungi and bacteria. A total of 55 separate isolates were obtained from 20 plants, and 60% of these showed inhibitory activity against one or more pathogenic fungi and bacteria. Actinomycetes were most commonly recovered from roots (54.5% of all isolates), followed by stems (23.6%), and leaves (21.8%). The dominant genus was Streptomyces (49.09% of all isolates), while Streptosporangium (14.5%), Microbispora (10.9%), Streptoverticillium (5.5%), Sacchromonospora sp. (5.5%), and Nocardia (3.6%) were also recovered. Streptomyces isolates AzR 006, 011, and 031 (all from roots) had acute activity against Pseudomonas fluorescens, while AzR027, 032, and 051 (also all from roots) showed activity against Escherichia coli. Meanwhile, an isolate of Nocardia sp. from leaves (AzL025) showed antagonism against Bacillus subtilis. Overall, 32 of the 55 were found to have broad spectrum significant antimicrobial activity, while about 4% of them showed strong and acute inhibition to pathogenic fungi and bacteria. Isolates of Streptomyces AzR031, 008, and 047, Nocardia sp. AzL025, and Streptosporangium sp. AzR 021 and 048 are of particular interest because they showed significant antagonistic activity against root pathogens, including Pythium and Phytophthora sp. Thus, many of the isolates recovered from A. indica in this study may be used in developing potential bio-control agents against a range of pathogenic fungi and bacteria and in the production of novel natural antimicrobial compounds. These results not only further our understanding of plant–microbe interactions but also indicate that there is an untapped resource of endophytic microorganisms that could be exploited in the biotechnological, medicinal, and agricultural industries.

210 citations


Journal ArticleDOI
TL;DR: This work demonstrates the possible use of biologically synthesized silver nanoparticles by its incorporation in cloths leading them to sterilization.
Abstract: Silver nanoparticles are known to have bactericidal effects. A new generation of dressings incorporating antimicrobial agents like silver nanoparticles is being formulated to reduce or prevent infections. The particles can be incorporated in materials and cloth rendering them sterile. Recently, it was found that aqueous silver ions can be reduced by aqueous extract of plant parts to generate extremely stable silver nanoparticles in water. Apart from being environmentally friendly process, use of Neem leaves extract might add synergistic antibacterial effect of Neem leaves to the biosynthesized nanoparticles. With this hypothesis the biosynthetic production of silver nanoparticles by aqueous extract of Neem leaves and its bactericidal effect in cotton cloth against E. Coli were studied in this work. Silver nanoparticles were synthesized by short term (1 day) and long term (21 days) interaction of Neem extract (20% w/v) and 0.01 M AgNO3 solution in 1:4 mixing ratio. The synthesized particles were characterized by UV visible spectroscopy, transmission electron microscopy, and incorporated into cotton disks by (i) centrifuging the disks with liquid broth containing nanoparticles, (ii) in-situ coating process during synthesis, and (iii) coating with dried and purified nanoparticles. The antibacterial property of the nanoparticles coated cotton disks was studied by disk diffusion method. The effect of consecutive washing of the coated disks with distilled water on antibacterial property was also investigated. This work demonstrates the possible use of biologically synthesized silver nanoparticles by its incorporation in cloths leading them to sterilization.

161 citations


Journal ArticleDOI
TL;DR: The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions and may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control.
Abstract: Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae) and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes.

142 citations


Journal ArticleDOI
TL;DR: How a developing country like Nigeria can harness the numerous opportunities presented by the multi-biological and multi-pharmacological nature of A. indica to solve some of her myriad problems, including those in the agricultural, health and economic sectors is reviewed.
Abstract: Azadirachta indica, commonly called neem or ‘dogonyaro’ in Nigeria, is a plant that has found varied use in ecological, medicinal and agricultural sectors. Biological and pharmacological activities attributed to different parts and extracts of these plants include antiplasmodial, antitrypanosomal, antioxidant, anticancer, antibacterial, antiviral, larvicidal and fungicidal activities. Others include antiulcer, spermicidal, anthelminthic, antidiabetic, anti-implantation, immunomodulating, molluscicidal, nematicidal, immunocontraceptive, insecticidal, antifeedant and insect repellant effects. But toxicological activities such as allergic, genotoxic, cytogenetic and radiosensitizing effects have also been reported in humans and some economic animals, particularly, aquatic organisms, chicks and goats. Bioassay-guided studies and phytochemical analyses utilizing modern state-of-the-art techniques such as HPLC–MS, GC–MS, NMR and Infra Red spectroscopy have revealed that phytocompounds like azadirachtins, nimocinol, isomeldenin, azadirachtol (a tetranortriterpernoid), 2,3′-dehydrosalanol gedunin, nimbin, nimolicinol, odoratone, azadironolide, isoazadironolide, naheedin and mahmoodin are responsible for the varied biological, pharmacological and toxicological properties observed. In this paper, we review how a developing country like Nigeria can harness the numerous opportunities presented by the multi-biological and multi-pharmacological nature of A. indica to solve some of her myriad problems, including those in the agricultural, health and economic sectors.

141 citations


Journal ArticleDOI
TL;DR: The ethnobotanical efficacy of Indian medicinal plants; Achyranthes aspera, Artemisia parviflora, Azadirachta indica, Calotropis gigantean, Lawsonia inermis, Mimosa pudica, Ixora coccinea, Parthenium hysterophorus and Chromolaena odorata were found to be ineffective or showed poor inhibition on tested human and phytopathogenic bacteria.
Abstract: The ethnobotanical efficacy of Indian medicinal plants; Achyranthes aspera, Artemisia parviflora, Azadirachta indica, Calotropis gigantean, Lawsonia inermis, Mimosa pudica, Ixora coccinea, Parthenium hysterophorus and Chromolaena odorata were examined using agar disc diffusion method against clinical bacteria (Escherichia coli and Staphylococcus aureus) and phytopathogenic bacteria (Xanthomonas vesicatoria and Ralstonia solanacearum). Leaves were extracted using different solvents such as methanol, ethanol, ethyl acetate and chloroform. Among treatments, maximum in vitro inhibition was scored in methanol extracts of C. odorata which offered inhibition zone of 10, 9, 12 and 12 mm against E. coli, S. aureus, X. vesicatoria and R. solanaccearum, respectively, followed by chloroform extract of the same plant leaf with inhibition zone of 8, 4, 4 and 4 mm, respectively. A significant inhibition of E. coli was found in aqueous and in all tested solvent extracts of A. indica. In case of S. aureus, maximum inhibition of 8 mm was obtained in aqueous extracts of A. indica and 6 mm from methanol extract of L. inermis. The minimum inhibitory concentration (MIC) value for the clinical bacteria ranged between 0.35 to 4.0 mg/ml and 0.25 to 4.0 mg/ml for phytopathogenic bacteria when tested with all four solvents extracts of C. odorata. Whereas, extracts of A. aspera, A. parviflora, C. gigantean, L. inermis, M. pudica and I. coccinea were found to be ineffective or showed poor inhibition on tested human and phytopathogenic bacteria.

138 citations


Journal ArticleDOI
TL;DR: The X-ray structure confirms the previously elucidated structure of the compound that was done under standard spectroscopic methods and the importance of javanicin in establishing symbiosis between Chloridium sp.
Abstract: The endophytic fungus Chloridium sp. produces javanicin under liquid and solid media culture conditions. This highly functionalized naphthaquinone exhibits strong antibacterial activity against Pseudomonas spp., representing pathogens to both humans and plants. The compound was crystallized and the structure was elucidated by X-ray crystallography. The X-ray structure confirms the previously elucidated structure of the compound that was done under standard spectroscopic methods. The importance of javanicin in establishing symbiosis between Chloridium sp. and its host plant, Azadirachta indica, is briefly discussed.

127 citations


Journal ArticleDOI
TL;DR: In this article, HPLC method was employed to quantify the amount of azadirachtin and nimbin present in the seed, leaf and the bark extracts of neem.
Abstract: The leaf and bark fraction extracts of Azadirachta indica A. Juss. (neem) grown in the foothills (subtropical region) of Nepal were evaluated for their antioxidant activity, total phenolic (TP) and total flavonid (TF) contents. HPLC method was employed to quantify the amount of azadirachtin and nimbin present in the seed, leaf and the bark extracts of neem. The result showed that the highest azadirachtin content was found in the methanolic extract of the seed (3300 ig/g dw). Similarly, the hexane fraction of bark showed the highest nimbin content (271 ig/g dw) followed by the methanolic extract (260 ig/g dw). Antioxidant activity was determined by measuring 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, hydroxyl radical scavenging activity, DNA protection assay, metal chelating and the inhibition of peroxidation using linoleic acid system and their results were found at different magnitudes of potency. The results of TP content expressed in tannic acid equivalents ranged from 66.63 to 629.04 ig/mg in the bark extracts and 23.85 to 237.00 ig/mg in the leaf extracts. Likewise, the content of TF expressed in quercetine equivalents ranged from 12.87 to 17.07 ig/mg in the bark and 13.72 to 93.17 ig/mg in the leaf extracts.

118 citations


Journal ArticleDOI
TL;DR: In this paper, the proximate vitamins and mineral elements and phytochemical compositions of Azadirachta indica, Vernonia amygdalina and Gongronema latifolium were quantitatively determined using standard methods and compared.
Abstract: As part of an investigation into the antidiabetic mechanism of some indigenous medicinal plants, the proximate, vitamins and mineral elements and phytochemical compositions of Azadirachta indica, Vernonia amygdalina and Gongronema latifolium were quantitatively determined using standard methods and compared. Of the 3 plants G. latifolium had highest (p<0.05) crude protein and fat contents but lowest in fibre composition, whereas A. indica with highest fibre content had lowest crude protein composition. Fat and ash were lowest in V. amygdalina . Also G. latifolium showed highest composition (p<0.05) of vitamins A, E and niacin content compared to A. indica and V. amygdalina. A. indica and V. amygdalina have higher (p<0.05) vitamin C and riboflavin composition. Flavonoids, saponins and polyphenols were significantly predominant (p<0.05) in V. amygdalina relative to A. indica and G. latifolium , whereas alkaloids and HCN were highest (p<0.05) in A. indica . However, G. latifolium had the highest composition of tannins among the three plants. There appear to be a complement of biochemicals in the leaves of these plants which may account for reported hypoglycemic and antihyyperglycemic action.

114 citations


Journal ArticleDOI
TL;DR: A decrease in Bcl-2/Bax ratio with increased expression of Apaf-1 and caspase-3, and cleavage of poly(ADP-ribose) polymerase provide compelling evidence that nimbolide-induced apoptosis is mediated by the mitochondrial pathway.
Abstract: We investigated the cytotoxic effects of nimbolide, a limonoid present in leaves and flowers of the neem tree (Azadirachta indica) on human choriocarcinoma (BeWo) cells. Treatment with nimbolide resulted in dose- and time-dependent inhibition of growth of BeWo cells with IC50 values of 2.01 and 1.19 μM for 7 and 24 h respectively, accompanied by downregulation of proliferating cell nuclear antigen. Examination of nuclear morphology revealed fragmentation and condensation indicating apoptosis. Increase in the generation of reactive oxygen species (ROS) that was reversed by addition of reduced glutathione suggested ROS involvement in the cytotoxicity of nimbolide. A decrease in Bcl-2/Bax ratio with increased expression of Apaf-1 and caspase-3, and cleavage of poly(ADP-ribose) polymerase provide compelling evidence that nimbolide-induced apoptosis is mediated by the mitochondrial pathway. The results of the present study suggest that nimbolide has immense potential in cancer prevention and therapy based on its antiproliferative and apoptosis inducing effects.

101 citations


Journal ArticleDOI
TL;DR: All of the 32 compounds isolated from the seed extract of Azadirachta indica exhibited moderate or potent inhibitory effects against the Epstein-Barr virus early antigen (EBV-EA) activation induced by TPA.
Abstract: Thirty-one nortriterpenoids, including 28 limonoids (1-28) and 3 degraded limonoids (29-31), and one diterpenoid (32), were isolated from the seed extract of Azadirachta indica (neem). Among these, six were new compounds and their structures were established to be 15-hydroxyazadiradione (3), 7-benzoyl-17-hydroxynimbocinol (5), 23-deoxyazadironolide (12), limocin E (13), 23-epilimocin E (14), and 7alpha-acetoxy-3-oxoisocopala-1,13-dien-15-oic acid (32). Upon evaluation of compounds 1-32 on the melanogenesis in the B16 melanoma cells, five compounds, 20, 26, 27, 29, and 31, exhibited marked inhibitory effect (74-91% reduction of melanin content at 25 microg/mL) with no or almost no toxicity to the cells. Seven compounds, 1, 6, 9, 10, 18, 20, and 26, on evaluation for their inhibitory effect against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 microg/ear) in mice, exhibited, except for compound 26, marked anti-inflammatory activity (ID(50) values 0.09-0.26 mg/ear). In addition, all of the 32 compounds exhibited moderate or potent inhibitory effects (IC(50) values of 230-501 mol ratio/32 pmol TPA) against the Epstein-Barr virus early antigen (EBV-EA) activation induced by TPA. Furthermore, on evaluation of azadirachtin B (21) for its anti-tumor-initiating activity on the two-stage carcinogenesis of mouse skin tumor induced by peroxynitrite (ONOO-; PN) as an initiator and TPA as a promoter, this exhibited marked inhibitory activity.

01 Jan 2009
TL;DR: The results show that the Azadirachtin is promising as a larvicidal agent against Culex pipiens, naturally ocurring biopesticide could be an alternative for chemical pesticides.
Abstract: An insecticide containing azadirachtin, a tree ﺮﻴﺛﺄﺗ ﺔﺳارد ﺚﺤﺒﻟا اﺬه لوﺎﻨﺗ (Azadirachta indica) extract, was tested against Culex pipiens mosquito larvae and pupae in east of the Republic of Algeria under laboratory conditions. First, after treatment of larval stage, LC50 and LC90 values for Azadirachtin were 0.35 and 1.28 mg/L in direct effect and 0.3-0.99 mg/l in indirect effect, respectively. Second, after treatment of the pupal stage, the LC50 and LC90 in direct effect were measured as0.42 -1.24mg/l and in indirect effect was 0.39mg/l-1.14mg/l respectively. Mosquito adult fecundity were markedly decreased and sterility was increased by the Azadirachtin after treatment of the fourth instar and pupal stage. The tretment also prolonged the duration of the larval stage. The results show that the Azadirachtin is promising as a larvicidal agent against Culex pipiens, naturally ocurring biopesticide could be an alternative for chemical pesticides.

Journal ArticleDOI
TL;DR: In the search of developing herbal acaricides, eight medicinal plants were screened for their efficacy against Boophilus microplus, the widely distributed tick species in India, and the extracts prepared from the Annona squamosa seed showed very high level of efficacy after 24 h of treatment.
Abstract: In the search of developing herbal acaricides, eight medicinal plants were screened for their efficacy against Boophilus microplus, the widely distributed tick species in India. Of the seven extracts screened, the extracts prepared from the Annona squamosa seed showed very high level of efficacy (70.8%) after 24 h of treatment. The effect of treatment on oviposition of the survived ticks was also assessed, and a significant reduction (P < 0.05) in the reproductive index was noted in comparison to control. When efficacy of the in vitro optimized concentration of A. squamosa was compared with previously tested extract of Azadirachta indica in in vivo model, it was observed that the extracts prepared from A. indica is more efficacious than the extracts of A. squamosa. A comparable efficacy against B. microplus fed on animals treated with herbal extracts and commonly used synthetic acaricide was noted. The possibility of using the herbal extracts in IPM format for the management of ticks is discussed.

Journal ArticleDOI
TL;DR: Two new solanapyrone analogues and three known compounds were isolated from the fermentation culture of Nigrospora sp.
Abstract: Two new solanapyrone analogues, solanapyrones N and O (1 and 2, resp.), and three known compounds, solanapyrone C (3), nigrosporalactone (4), and phomalactone (5), were isolated from the fermentation culture of Nigrospora sp. YB-141, an endophytic fungus isolated from Azadirachta indica A. Juss. The structures of the new compounds were elucidated on the basis of spectroscopic analysis. The antifungal activities of 1-5 towards seven phytopathogenic fungi were tested. Most of the compounds exhibited no or only weak antifungal activities.

Journal ArticleDOI
TL;DR: The study proved that the concoction-brewed compost (T1) is effective, inexpensive, easy to prepare and constitutes a sustainable and eco-friendly approach to control floral malformation in mango when it is sprayed at bud break stage and again at fruit set stage.
Abstract: Floral malformation caused by Fusarium mangiferae is a serious threat to mango cultivation in various countries. Different long-term measures suggested to control it were found to be unsuccessful. Present studies clearly showed strong antifungal activity of a concoction brewed from Datura stramonium, Calotropis gigantea, Azadirachta indica (neem) and cow manure (T1) followed by methanol-water (70/30 v/v) extracts of Datura stramonium, Calotropis gigantea and Azadirachta indica (T2) against Fusarium mangiferae. Optimal control of floral malformation was found in trees sprayed with T1 followed by T2 at bud break stage and again at fruit set stage when compared with the control. All the malformed buds or panicles completely dried two days after foliar spray with T1 or T2. In the trees treated with T1 at fruit set stage, flower abscission was observed from the fourth day after spraying and all flowers dropped by the ninth day without requiring any manual de-blossoming, whereas in the control, the malformed panicles remained green and competed with the growing fruits for plant nutrients. In vitro culture of fresh malformed tissues in MS media along with T1 or T2 showed no growth of any fungus in the media. However, in vitro culture of the completely dry malformed tissues in MS media after foliar treatment with T1 or T2 revealed growth of F. mangiferae on the twenty fifth day indicating that the concoction-brewed compost (T1) or methanol-water (70/30 v/v) extracts (T2) could not completely eliminate the pathogen but helped in controlling malformation by suppressing the activity of F. mangiferae. Mango trees sprayed with T1 and T2 revealed significant differences in percent fruit set and retention when compared with the control. This could be due to observed higher levels of nitrogen, phosphorus, potassium, calcium, magnesium, copper, zinc, iron and manganese in T1, followed by T2 when compared with T3 (control). Among the different fruit quality parameters analysed, the total flavonoids were found to be significantly higher in T1 and T2 when compared with T3. The study proved that the concoction-brewed compost (T1) is effective, inexpensive, easy to prepare and constitutes a sustainable and eco-friendly approach to control floral malformation in mango when it is sprayed at bud break stage and again at fruit set stage. In this present study, exogenous treatment of emerging buds with (Tc) further proved that with increase in the number of malformed panicles/tree the number of buds developing into healthy panicles/tree decrease.

Journal ArticleDOI
TL;DR: In this article, the authors used gravimetric, gasometric and IR methods to study the corrosion of mild steel in H 2SO 4 using Azadirachta indica extracts.
Abstract: The corrosion of mild steel in H 2SO 4 was studied using gravimetric, gasometric and IR methods. The results indicate that the rate of corrosion of mild steel in H 2SO 4 increases with increase in the concentration of the acid and that ethanol extracts of the seeds and leaves of Azadirachta indica inhibit the corrosion of mild steel in H 2SO 4. Inhibition efficiencies of the leaves and seeds extract range from 82.62 to 94.24% and from 60.55 to 84.78%, respectively. The inhibition potential of these extracts is attributed to the presence of tannin, saponin, glycoside, anthraquinone, flavonone and other phytochemicals in the extracts. IR study confirms that the inhibitors are adsorption inhibitors and the adsorption of the inhibitors on mild steel surface is exothermic, spontaneous and consistent with the assumptions of Flory-Huggins adsorption isotherm. Based on the values of the activation, free energy of adsorption and the variation of inhibition efficiency with temperature, a physical adsorption mechanism is proposed for the adsorption of ethanol extract of leaves and seeds of Azadirachta indica on the surface of mild steel.

Journal ArticleDOI
TL;DR: This review deals with the pharmacological and biochemical studies carried out regarding the antiulcer activities of Neem extracts and their mechanism of action, including the inhibition of acid secretion.
Abstract: H(2)-receptor blockers and proton pump inhibitors are now used extensively to control gastric and duodenal ulcer, inflammation and pain, but these drugs have limitations and are not always affordable. The development of novel nontoxic antiulcer drugs, including from medicinal plants, is therefore desirable, and Azadirachta indica A. Juss, commonly known as Neem, is known to have potent gastroprotective and antiulcer effects. This review deals with the pharmacological and biochemical studies carried out regarding the antiulcer activities of Neem extracts and their mechanism of action, including the inhibition of acid secretion. A comparison with ranitidine and omeprazole in some animal models has been included and clinical studies, where available, have also been incorporated, along with a safety evaluation. Neem bark extract has the potential for the development of novel medicines for the therapeutic control of gastric hyperacidity and ulcer.

Journal Article
TL;DR: In the present study, aqueous extract of eight plants, namely Azadirachta indica A. azedarach, N. indicum and A. indica were tested for antifeedant and toxic effects against Pieris brassicae (Linn.) and ethanol extract of four potential plants were further tested for their biological activity against the test insects.
Abstract: In the present study, aqueous extract of eight plants, namely Azadirachta indica A. Juss, Melia azedarach Linn., Lantana camara L. Moldenke., Cannabis sativa Linn., Nerium indicum Mill., Eucalyptus sp., Ricinus communis Linn. and Solanum nigrum Linn. were tested for antifeedant and toxic effects against Pieris brassicae (Linn.). The ethanol extract of four potential plants were further tested for their biological activity against the test insects. Aqueous extract of A. indica and M. azedarach repelled maximum number of larvae protected 94.0 per cent and 89.2 per cent cabbage foliage, respectively. Aqueous extract of M. azedarach, N. indicum and A. indica showed higher mortality of larvae (19.6, 19.6 and 18.5%, respectively) while R. communis was the least toxic resulting in 8.9 per cent larval mortality. In case of ethanol extract, seed extract of M. azedarach protected 58.3 per cent cabbage foliage while Eucalyptus sp. protected minimum cabbage foliage. The maximum protection to the cabbage foliage was provided at 5 per cent of M. azedarach (88.3%) and A. indica (82.5%). Ethanol extract of A. indica exhibited statistically higher larval mortality of 50.0 per cent and N. indicum the lowest mortality of 3.2 per cent. In general, antifeedant and larval mortality was dose dependent.

Journal ArticleDOI
TL;DR: Azadirachtin did not provide adequate control of nematodes, at the recommended or higher doses, and further research will be necessary to improve the efficacy of azadIRachtin against Meloidogyne incognita.

Journal ArticleDOI
TL;DR: The extract of A. muricata (seed) had the highest mortality with acaricide activity and 100% efficacy followed by extracts of S. malaccensis (75 and 59.24%) and A. indica (65 and 38.49%).
Abstract: Plant extracts were studied to evaluate its efficiency in the control of Rhipicephalus (Boophilus) microplus (Canestrini, 1887) in laboratory. Engorged female ticks were collected from the cattle, kept in Petri dishes. Organic alcoholic extracts 2% (weight/volume) were used: seeds of Annona muricata L. (Annonaceae) (soursop); flowers of Syzygium malaccensis (L.) (Myrtaceae) (iamb), leaves of Cymbopogon citratus (DC.) Stapf (Poaceae) (holy grass), leaves of Azadirachta indica A. Juss (Meliaceae) (neem) and hexane extract 2% (weight/volume) of A. indica (seeds). The control groups consisted of untreated females and females treated with distilled water and sterile and dimethylsulfoxide (DMSO) a concentration of 1%. The extract of A. muricata (seed) had the highest mortality with acaricide activity and 100% efficacy followed by extracts of S. malaccensis (75 and 59.24%) and A. indica (65 and 38.49%). The seed extract of A. muricata reduced 100% larvae hatch.

Journal ArticleDOI
TL;DR: Effects of some pure fractions of extracts from neem (Azadirachta indica) seeds on feeding activity and metamorphosis of Epilachna varivestis (Col. Coccinellidae) are investigated.
Abstract: Effects of some pure fractions of extracts from neem (Azadirachta indica) seeds on feeding activity and metamorphosis of Epilachna varivestis (Col. Coccinellidae) In a number of publications of various authors on the ingredients of neem tree (Azadirachta indica) seeds only azadirachtin was mentioned as an effective growth regulator in insects of various orders. This triterpenoid was also identified as a potent phagorepellent and sterilant. In the present investigation some fractions of extracts from neem seeds of West African origin (Togo) were purified. Four finally obtained pure fractions showed strong to very strong growth disruption effects in Epilachna varivestis, a fifthone was somewhat less active. After uptake of the neem seed ingredients by feeding on treated bean leaves various more-or-less typical symptoms appeared in fourth instar larvae. They can be described as follows: Under the influence of fractions 18-79a I and 18-79a II the larvae gradually shriveled until they died; fraction 18-79b I caused blackish legs in the shriveling test insects. After the uptake of fractions 18-80b and 18-80d reddish-brown spots appeared in the dorso-lateral zones of the thorax. The larvae showing this type of symptoms were very large and died not before about three weeks after appearance of such spots. Only fraction 18-79a I showed obvious phagorepellent properties mainly during the first day of the so-called “petri dish test”. Fractions 18-79a I, 18-79a II and 18-80b also prevented moulting from the 3rd to the 4th instar larva even in very low concentrations. After uptake of fraction 18-79b I and 18-80d the majority of 3rd instar larvae was able to moult but the resulting 4the instar larvae refused to feed on untreated bean leaves and died some days afterwards. Zusammenfassung In bisherigen Veroffentlichungen uber Inhaltsstoffe aus Neem-(Azadirachta indica-) Samen wurde lediglich das Triterpenoid Azadirachtin als metamorphosestorender Stoff bei Insekten verschiedener Ordnungen erwahnt. Gleichzeitig wurde es als sehr wirksames Phagorepellent identifiziert. Eine von laufenden Biotesten begleitete Fraktionierung der Extrakte aus Neem-Samen westafrikanischer Herkunft ergab, das insgesamt vier stark bis sehr stark und ein weiterer, schwacher wirksamer Inhaltsstoff vorhanden sind, die tiefgreifende Einflusse auf die Metamorphose von Epilachna varivestis ausuben konnen. An Viertlarven treten nach oraler Aufnahme der Wirkstoffe unterschiedliche, mehr oder weniger typische Symptome auf, die sich in drei Gruppen einteilen lassen: Bei den Reinfraktionen 18-79a I und 18-79a II schrumpfen die Testtiere allmahlich zusammen, bei 18-79b I werden vor dem Einschrumpfen des Korpers die Beine schwarz. Bei den Fraktionen 18-80b und 18-80d treten auf dem Thorax 1–4 rotbraune Flecke auf und die Larven sterben erst nach mehreren Wochen ab. Lediglich die Fraktion 18-79a I zeigt eine deutliche frasabschreckende Wirkung, besonders wahrend des 1. Versuchstages. Die Fraktionen 18-79a I, 18-79a II und 18-80b verhindern selbst in sehr niedriger Konzentration die Hautung von der L3 zur L4. Die Reinfraktionen 18-79b I und 18-80d konnen die Hautung zwar bei den meisten L3 nicht verhindern, doch sterben die L4 dann wenige Tage spater, meist ohne vorher noch Futter aufgenommen zu haben.

Journal ArticleDOI
23 Jul 2009-Toxins
TL;DR: Given its accessibility and low cost, neem oil could be implemented as part of a sustainable integrated pest management strategy for plant disease, as it has been shown to be fungitoxic by inhibition of growth and sporulation.
Abstract: In vitro trials were conducted to evaluate the effect of Azadirachta indica (neem) extracts on mycelial growth, sporulation, morphology and ochratoxin A production by P. verrucosum and P. brevicompactum. The effect of neem oil extract from seeds and leaf was evaluated at 0.125; 0.25 and 0.5% and 6.25 and 12.5 mg/mL, respectively, in Yeast Extract Sucrose (YES) medium. Ochratoxin A production was evaluated by a thin-layer chromatography technique. Oil extracts exhibited significant (p ≤ 0.05) reduction of growth and sporulation of the fungi. No inhibition of ochratoxin A production was observed. Given its accessibility and low cost, neem oil could be implemented as part of a sustainable integrated pest management strategy for plant disease, as it has been shown to be fungitoxic by inhibition of growth and sporulation.

Journal Article
TL;DR: Ex vitro rooting and use of the bio-control agent could bring down the cost of production and make micropropagation of neem feasible and to be adopted as a rural enterprise.
Abstract: The hardening of in vitro propagated microshoots of neem (Azadirachta indica A. Juss.) was carried out using 3 methods under semi-sterile conditions in low cost mini-polytunnels and a shade house. The percentage survival and rooting response was 16.25% in the first (2:1, v/v, sand and soil with 1�� × 1 �� central cylindrical cocopeat plugs) and second method (1:1, v/v, cocopeat : bio-fertilizer), but was 100% in the third method (2:1, v/v, sand and soil with 1:1, v/v, cocopeat:biofertilizer and addition of Trichoderma viride. During the acclimatization process, the chlorophyll content in leaves gradually increased from 0.97 (stage I) to 1.35 (stage II), 1.56 (stage III) and 2.14 mg/g (stage IV), indicating a shift in the mode of nutrition from heterotrophic through myxotrophic to autotrophic. Similarly, the percentage water loss from the leaves of plantlets decreased from 90.38 (stage I) to 46.83% (stage IV), indicating stomatal development and progressive hardening. Ex vitro rooting and use of the bio-control agent could bring down the cost of production and make micropropagation of neem feasible and to be adopted as a rural enterprise.

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TL;DR: A protocol for somatic embryogenesis in Azadirachta indica A Juss has been standardized using in vivo leaflets and the histological study of somatic embryos showed resembles to zygotic embryos.
Abstract: A protocol for somatic embryogenesis in Azadirachta indica A Juss. has been standardized using in vivo leaflets. Experiments were carried out to examine the effect of various auxins, cytokinins, sucrose, inorganic and organic salts on subsequent somatic embryo induction and maturation. Embryogenic calli were induced on Murashige and Skoog (MS) medium supplemented with 1.5 mg dm−3 kinetin and 1.5 mg dm−3 indole-3-acetic acid and subsequently all the stages of somatic embryo development (globular, cordate, torpedo and cotyledonary) were observed. Maturation of these embryos was accomplished with the same growth regulators after three subcultures. The histological study of somatic embryos showed resembles to zygotic embryos. The matured somatic embryos were transferred onto half strength MS-medium devoid of growth regulators for their germination (82 %). Plantlets were acclimatized in the field with a survival rate of 80–83.5 %.

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TL;DR: Aqueous extracts of neem wood and bark chippings can be produced locally and their use has the potential to be a low-tech component of integrated malaria vector control schemes in sub-Saharan Africa.
Abstract: Azadirachta indica A. Juss (the neem tree), a source of limonoid insect growth regulatory (IGRs), grows well in many places in sub-Saharan Africa. We explored the potential of neem wood and bark chippings in malaria vector control by evaluating their aqueous extracts as a larvicide and growth disruptor of Anopheles gambiae s.s. (Diptera: Culicidae) under laboratory conditions. Immature stages of the mosquito were tested using WHO guidelines. Fifty percent inhibition of adult emergence (IE50) of all larval instars was obtained with <0.4 g of neem chippings in 1 liter of distilled water. For pupae, significant mortality occurred at 5 g/liter. Inhibition of pupation was seen with some larvae staying as LIVs for 9 d before dying. In addition to growth retardation, reduced reaction by larvae to visual and mechanical stimuli observed at higher neem concentrations may make them more susceptible to natural predators. There were no significant differences in the sex ratio of emerged adults or wing length of females compared with the controls. High-performance liquid chromatography of aqueous extracts showed a series of constituents of varying polarity, including the limonoids nimbin and salannin, which were quantified. Azadirachtin was not detected and the observed activities are attributed to other constituents of the chippings. Such larvicides can be particularly effective where larval habitats are relatively large and readily identifiable. Aqueous extracts of neem wood chippings can be produced locally and their use has the potential to be a low-tech component of integrated malaria vector control schemes in sub-Saharan Africa.

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TL;DR: In this paper, the optimal ratio between carrageenan and chitosan to form a stable polyelectrolyte complex was found as 1 : 0.36.
Abstract: Microcapsules containing neem (Azadirachta Indica A. Juss.) seed oil (NSO) were prepared by encapsulation of natural liquid pesticide NSO in a polyelectrolyte complex of κ-carrageenan and chitosan. The optimum ratio between carrageenan and chitosan to form a stable polyelectrolyte complex was found as 1 : 0.36. The microencapsulation method for NSO loading was also optimized. SEM study demonstrated that the surface of the microcapsules became more irregular as oil loading increased. The release rates of NSO were studied by varying the percentage of oil loading, concentration of cross-linking agent, and polymer concentration. Fourier transform infrared spectroscopy (FTIR) study confirmed the complex formation between κ-carrageenan and chitosan. Differential scanning calorimetry (DSC) and FTIR study indicated the absence of any significant interaction between polyelectrolyte complex of κ-carrageenan -chitosan and NSO. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

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TL;DR: A statistical evaluation of variance showed a significant difference between mycelial radial growths values recorded on the various plant extracts concentrations used compared with the control, which indicated that the extracts were sparingly effective for a short period on the field experiment.
Abstract: A study on the use of ginger ( Zingiber officinale ), aloe ( Aloe ve ra), bitter kola ( Garcinia cola ) and neem ( Azadirachta indica ) extracts in the control of root rot of cowpea caused by Pythium aphanidermatum was carried out in vitro and in the field ( in vivo ). They were evaluated for their antifungal activity over P. aphanidermatum , a rot fungus of many economic crops. Vegetative growth values over the fungus at 40, 60, 80 and 100% concentrations were generally low compared with the control, complete inhibition of fungal mycelia growth was exhibited at all concentrations in ginger extract. Aloe at 60% completely inhibited mycelial growth; this was followed by bitter kola with only retardation of mycelial growth while neem was the least effective. Highest mycelial dry weight was noticed on bitter kola extract but more sporangia formation in neem after a prolong incubation. However, the extracts were sparingly effective for a short period on the field experiment. A statistical evaluation of variance showed a significant difference between mycelial radial growths values recorded on the various plant extracts concentrations used compared with the control.

Journal Article
TL;DR: The results of the study indicate that the inclusion of neem leaf meal up to 15% in the ration of matured rabbit bucks could cause mild depressive effect on the spermatogenesis, semen quality and seminiferous tubule diameter.
Abstract: Background: To ascertain the effects of tropical leaf meals on semen production and semen quality. Objective: This study was conducted with the main objective of investigating the effect of neem leaf meal on physiological responses of rabbit bucks fed graded levels of neem leaf (Azadirachta indica A. Juss) meal. Materials and Methods: The varying levels of neem leaf meal (NLM) in the different experimental diets were 0, 5, 10 and 15% respectively. Four groups of nine crossbred New Zealand type rabbit bucks each, aged 7-8 months were randomly assigned to four diets containing neem leaf meal (NLM) at 0% (control) (CD0), 5% (CD1), 10% (CD2) and 15% (CD3) respectively for 16 weeks. Results: The sperm concentration values obtained were 20.15 ×106 /ml, 18.04×106 /ml, 13.65×106 /ml, 6.46 ×106 /ml for the CD0, CD1, CD2 and CD3 groups respectively. The results obtained indicate that sperm motility were lowest (pl0.05) in the treatment groups than the control group. Total sperm per ejaculate was similar (pg0.05) between the control and those on 5–10 %NLM dietary groups however, the value for the 15%NLM group was significantly (pl0.05) lower than that of the control. Abnormal sperm percentage of the bucks fed 15% NLM was significantly (pl0.05) higher than those bucks on CD1, CD2 and CD3 groups. The seminiferous tubule diameters were significantly smaller in the 15% NLM (203µm) than the other 3 dietary groups. All the other variables measured including semen volume, weight of testis and reaction time did not differ (pg0.05) among the experimental group. Conclusion: The results of the study indicate that the inclusion of neem leaf meal up to 15% in the ration of matured rabbit bucks could cause mild depressive effect on the spermatogenesis, semen quality and seminiferous tubule diameter.

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TL;DR: Results provide evidence for the chemopreventive efficacy of neem leaf fractions in the rat mammary tumour model, with EAF rich in constituent phytochemicals was more effective than MF in modulating multiple molecular targets.

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TL;DR: The studies suggest that the antioxidant and protective effects of active neem leaf fractions against H2O2-induced lipid peroxidation and pBR322 DNA damage can be attributed to their ability to inhibit various free radicals.
Abstract: We evaluated the protective effects of subfractions of the ethyl acetate fraction (EAF) and the methanolic fraction (MF) from the crude ethanolic extract (CEE) of Azadirachta indica A. Juss (neem) leaves against various free radicals and hydrogen peroxide (H 2 O 2 )-induced oxidative damage to red blood cells (RBCs) and pBR322 DNA. Neem leaf fractions reduced DPPH * , ABTS ++ , superoxide (O ·― ), hydroxyl (OH'), and nitric oxide radicals to nonradical forms in a concentration-dependent manner. Treatment with the benzene insoluble fraction from EAF (EBIF), the chloroform insoluble fraction from EAF (ECIF), the chloroform insoluble fraction from MF (MCIF), and the ethyl acetate insoluble fraction from MF (MEIF) significantly mitigated H 2 O 2 -induced oxidative damage to RBCs and pBR322 DNA. Although we found low in vitro free radical scavenging activity for the benzene insoluble fraction from EAF (EBSF), the chloroform soluble fraction from EAF (ECSF), the chloroform soluble fraction from MF (MCSF), and the ethyl acetate soluble fraction from MF (MESF), these fractions showed no effect on H 2 O 2 -induced lipid peroxidation and pBR322 DNA damage. High-performance liquid chromatography (HPLC) and TLC-latroscan analysis revealed that the greater efficacy of EBIF, ECIF, MCIF, and MEIF may be due to the presence of more polar compounds such as nimbolide and quercetin. Our studies suggest that the antioxidant and protective effects of active neem leaf fractions against H 2 O 2 -induced lipid peroxidation and pBR322 DNA damage can be attributed to their ability to inhibit various free radicals.