Showing papers on "Azadirachta published in 2006"

Bioefficacy of some plant derivatives that protect grain against the pulse beetle, Callosobruchus maculatus.

Abstract: Experiments were conducted to study the bioefficacies of different plant/weed derivatives that affect the development of the pulse beetle, Callosobruchus maculates F. (Coleoptera: Bruchidae) fed on black gram, Vigna mungo, seeds. Plant extracts, powder, ash and oil from nishinda (Vitex negundo L.), eucalyptus (Eucalyptus globules Labill.), bankalmi (Ipomoea sepiaria K.), neem (Azadirachta indica L.), safflower (Carthamus tinctorius L.), sesame (Sesamum indicum L.) and bablah (Acacia arabica L.) were evaluated for their oviposition inhibition, surface protectant, residual toxicity and direct toxicity effects on C. maculates. The results showed that plant oils were effective in checking insect infestation. The least number of F1 adults emerged from black gram seeds treated with neem oil. The nishinda oil extract was the most toxic of three extracts tested (nishinda, eucalyptus and bankalmi). Bablah ash was the most effective compared to the powdered leaves of nishinda, eucalyptus and bankalmi. The powdered leaves and extracts of nishinda, eucalyptus and bankalmi, at a 3% mixture, provided good protection for black gram seeds by reducing insect oviposition, F1 adult emergence, and grain infestation rates. The oil treatment did not show adverse effects on germination capability of seeds, even after three months of treatment.

New dimension of medicinal plants as animal feed

Abstract: The medicinal plants and herbs have been used for many years in the treatment of various diseases in animals and human beings. Now-a-days, utilization of these medicinal plants is increasing. These are used in animal feed as the growth promoters. Due to prohibition of most of the antimicrobial growth promoters in animal feed because of their residual effects, plant extracts are becoming more popular. They act as antibacterial, antioxidant, anticarcinogenic, antifungal, analgesic, insecticidal, anticoccidial and growth promoters. These plant extracts compete with the synthetic drugs. Majority of medicinal plants do not have the residual effects. Azadiracht indica, Zizyphus vulgaris, Ocimum gratissimum and Atlanta monophylla have the strong antibacterial activity, whereas ocimum plant has strong antioxidant, anticarcinogenic, antifungal, analgesic and antipyretic properties. Leaves of Azadirachta indica are used for feeding and reducing the parasitic load of animals. The fruit of Azadirachta indica also has the anticoccidial activity for poultry.

Root Extracts of Plants to Control Root-Knot Nematode on Edible Soybean

Abstract: Control of plant-parasitic nematodes essentially involves use of synthetic nematicides However, apart from cost, increased concern for the environment has necessitated a reduction in the amount of nematicides used for control Additionally, there has been an increase in the search for other efficient; ecologically sound and safe control methods Eggs of root-knot nematode, Meloidogyne incognita (Kofoid & White) Chitwood, were exposed to concentrations of root extracts of Siam weed [Chromolaena odorata (L) King and Robinson], Neem (Azadirachta indica A Jass), Castor bean (Ricinus communis L) and Lemon grass (Cymbopogon citratus L) Undiluted (100%) concentrations of root extracts of Siam weed and Neem exhibited 100% inhibition of egg hatch and larval mortality, while the 100% concentration of root extracts of Castor bean and Lemon grass exhibited 93 and 95% inhibition of egg hatch and 62 and 75% larval mortality, respectively Egg hatch inhibition and larval mortality decreased as extracts we

Effects of a neem extract on blood feeding, oviposition and oocyte ultrastructure in Anopheles stephensi Liston (Diptera: Culicidae)

Abstract: Secondary metabolites of the neem tree (Azadirachta indica A. Juss., Meliaceae) exhibit a wide range of biological activities in insects. However, few studies have addressed the effects of neem extracts or compounds in arthropods of medical importance. In this study, a laboratory strain of Anopheles stephensi was used to assess the effects of a commercial formulation (Neem Azal® (NA)), containing azadirachtin A at 34%, on blood feeding, oviposition and oocyte ultrastructure. Oral administration of Neem Azal® to A. stephensi females through artificial blood meals did impair blood intake and oviposition in a concentration dependent manner. Similar results were obtained on females, which had consumed Neem Azal® in sucrose solution before taking a blood meal of plain blood. Neem treated females displayed a delay in oocyte development in both the phase of vitellogenesis and the phase of choriogenesis. The ultrastructural studies on ovaries from Neem Azal® treated females revealed distinct structural modifications indicative of: (i) a complete block of oogenesis, (ii) impairment of vitellogenesis and vitelline envelope formation, (iii) a severe degeneration of follicle cells. In agreement with results obtained in other insects, this study indicates that Neem Azal® impairs hormone control of oogenesis and exerts a cytotoxic effect on both follicular cells and oocytes of the Asian malaria vector A. stephensi.

A new shampoo based on neem (Azadirachta indica) is highly effective against head lice in vitro.

Abstract: Because topical compounds based on insecticidal chemicals are the mainstay of head lice treatment, but resistance is increasing, alternatives, such as herbs and oils are being sold to treat head lice. To test a commercial shampoo based on seed extract of Azadirachta indica (neem tree) for its in vitro effect, head lice (n=17) were collected from school children in Australia and immersed in Wash-Away Louse™ shampoo (Alpha-Biocare GmbH, Germany). Vitality was evaluated for more than 3 h by examination under a dissecting microscope. Positive and negative controls were a commercially available head lice treatment containing permethrin 1% (n=19) and no treatment (n=14). All lice treated with the neem shampoo did not show any vital signs from the initial examination after immersion at 5–30 min; after 3 h, only a single louse showed minor signs of life, indicated by gut movements, a mortality of 94%. In the permethrin group, mortality was 20% at 5 min, 50% at 15 min, and 74% after 3 h. All 14 head lice of the negative control group survived during the observation period. Our data show that Wash-Away Louse™ is highly effective in vitro against head lice. The neem shampoo was more effective than the permethrin-based product. We speculate that complex plant-based compounds will replace the well-defined chemical pediculicides if resistance to the commonly used products further increases.

Residues and persistence of neem formulations on strawberry after field treatment.

Abstract: Azadirachtoids were determined by liquid chromatography/mass spectrometry (LC/MS) in five methanolic seed extracts of the neem tree and in a commercial formulation. On average, seed extracts contain azadirachtin A (10.9%), azadirachtin B (3.5%), nimbin (10.4%), and large quantities of salannin (19.0%). The composition of the commercial formulations may present different azadirachtoids contents depending on the natural extracts used in the preparation. Because these compounds may also show insecticide activity, the efficacy on field of these formulations may be very different. Photodegradation of pure azadirachtoids was also studied. Azadirachtins and related compounds are very sensitive to sunlight, degrading rapidly, with half-lives of the order of 11.3 h for azadirachtin A and 5.5 h for azadirachtin B and few minutes for the other limonoids compounds studied. The residues of azadirachtins and the main constituents, e.g., salannin, nimbin, deacetylnimbin, and deacetylsalannin, of the neem seed extract were determined on strawberries after field treatment using two different formulations. This residue study on strawberry was carried out to assess not only the azadirachtin content but also the main azadirachtoids contents. Three days after field application at five times the dose recommended by the manufacturer, residues of azadirachtin A and B were 0.03 and 0.01 mg/kg, respectively, while residues of salannin (LOQ 0.01 mg/kg) and nimbin (LOQ 0.5 mg/kg) were not detectable.

Identification of an antimicrobial entity from the cyanobacterium Fischerella sp. isolated from bark of Azadirachta indica (Neem) tree

Abstract: The active principle in a methanolic extract of the laboratory-grown cyanobacterium, Fischerella sp. isolated from Neem (Azadirachta indica) tree bark was active against Mycobacterium tuberculosis, Enterobacter aerogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli as well as three multi-drug resistant E. coli strains in in vitro assays. Based on MS, UV, IR 1H NMR analyses the active principle is proposed to be hapalindole T having the empirical formula C21H23N2ClSO and a molecular weight of 386 with the melting point range 179–182 °C. The estimated production of Hapalindole T from the cyanobacterium is 1.25 mg g−1 lyophilized biomass. It is suggested that cyanobacteria colonizing specialized niches such as tree bark could be an antibacterial drug resource.

Adsorption and corrosion inhibitive properties of Azadirachta indica in acid solutions

Abstract: Purpose – To assess the protective effect and adsorption behaviour of Azadirachta indica extract in controlling mild steel corrosion in 1 M H2SO4 and 2 M HCl.Design/methodology/approach – The inhibitive effect of the plant extract was monitored using the gas‐volumetric technique. The inhibition mechanism was inferred by curve fitting of the experimental data to known adsorption isotherms and the trend of inhibition efficiency with temperature.Findings – Azadirachta indica extract effectively inhibited steel corrosion in the acid media studied by virtue of adsorption. The inhibitor adsorption characteristics were approximated by Langmuir isotherm. The extract functioned as a mixed inhibitor, depending on its concentration. The prime effect at lower concentration was mitigation of the cathodic reaction by physical adsorption of protonated species in the extract and at higher concentration the anodic reaction was inhibited by chemisorption of molecular species.Originality/value – This paper provides novel in...

Physiological Response Of Laying Birds To Neem (Azadirachta Indica) Leaf Meal-Based Diets: Body Weight Organ Characteristics And Haematology

Abstract: A 12-weeks feeding trial was conducted to evaluate the effects of Neem (Azadirachta indica) leafmeal (NLM) on body weight gain, carcass and organ characteristics and haematological values of laying hens. The leaves were harvested, chopped to facilitate drying in the sun until they became crispy but still greenish in coloration. The Sun-dried leaves were milled using a hammer mill to produce the leaf meal. Four layers diets were formulated to contain the NLM at 0%,5%, 10% and 15% dietary levels respectively and were used to feed 120 Shikka brown layers already 10 months in lay. The birds were divided into 4 groups of 30 each and randomly assigned to the 4 treatment diets in a completely randomized design (CRD). NLM did not show any appreciable difference in weight gain between the birds at 0% and those at 5%, 10% dietary levels. Carcass weight, dressed weight, liver, heart and gizzard weights were significantly (P<0.05) increased at 5% dietary level of NLM. There were no significant difference in Hb and PCV between birds on O% and 5% treatment diets. However, these differed significantly (P<0.05%) from those of birds on 10% and 15% treatment diets. There were variations in the differential WB count , marked lymphocytopenia adversely affected the total leucocyte counts in the birds on 5%, 10% and 15% treatment diets. The results of this study suggest that laying birds could tolerate 5%- 15% dietary levels of NLM without deleterious effects.

Azadirachta indica leaf extract induces resistance in sesame against Alternaria leaf spot disease

Abstract: Induced resistance is an important component of disease-resis tance response of plants, and is accompanied by increased capability for activating defense responses upon pathogen ingress or elicitor treatment. Aqueous leaf extract of neem (Azadirachta indica Juss.) provided the control of Alternaria leaf spot pathogen (Alternaria sesami) of sesame (Sesamum indicum L: Syn. S. orientale L). Treatment with this extract led to the changes in plant metabolism as leaves of the treated plants exhibited significantly high level of enzymes phenylalanine ammonialyase (PAL), peroxidase (PO) and content of phenolic compounds. Further more, germination of A. s e s a m i spores was not significantly inhibited by neem extract. It is therefore, suggested that, protection of sesame plants against A. s e s a m i by neem extract might be due to stimulation of plants natural defence response.

Daily feeding of fresh Neem leaves (Azadirachta indica) for worm control in sheep.

Abstract: This study was Conducted To Evaluate The Anthelmintic Effect Of Neem (azadirachta Indica) On Nematode Parasites Of Sheep. Twelve Santa Ines Cross Bred Sheep From A Government Farm were randomly selected and equally divided into control (n = 6) and treated groups (n =6). Faecal egg counts (FEC) using the modified McMaster technique and the FAMACHA score for assessing clinical anaemia were carried out daily and recorded for 6 weeks. At the end of the study all the animals were slaughtered and the total worm count (TWC) was done. The results of FEC showed that there was no significant difference between the control and treated group (p = 0.081). However, worm burden estimations showed that the number of parasites was significantly higher in the control group compared to the treated group (p < 0.05). This result indicated that feeding Neem had an effect on worm numbers in sheep, but was not reflected in their faecal egg counts. Further work is needed to reconfirm the effect of Neem on helminth infections of sheep.

Short Communication The toxicity and behavioural effects of neem limonoids on Cnaphalocrocis medinalis (Guenee), the rice leaffolder

Abstract: Meliaceae plant products have been shown to exert pesticidal properties against a variety of insect species. In agricultural pest control programs, such products may have the potential to be used successfully as botanical insecticides. The effect of the neem (Azadirachta indica) limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on the biology and mortality of rice leaffolder larvae was investigated. In laboratory experiments, treatment with neem limonoids suppressed leaf folding behaviour of C. medinalis. Biological parameters (larval duration, pupal duration adult longevity and fecundity) were also affected by the treatment. Azadirachtin, salannin, and deacetylgedunin showed high bioactivity at all doses, while the rest of the neem limonoids were less active, and were only biologically active at high doses. Azadirachtin was most potent in all experiments and produced almost 100% larval mortality at 1 ppm concentration. These results indicate neem limonoids affect the larval behaviour. These effects are most pronounced in early instars. 2005 Elsevier Ltd. All rights reserved.

Short Communication Effect of neem limonoids on lactate dehydrogenase (LDH) of the rice leaffolder, Cnaphalocrocis medinalis (Guenee) (Insecta: Lepidoptera: Pyralidae)

Abstract: Neem is derived from the neem tree Azadirachta indica A. Juss. (Meliaceae), and its primary insecticidal component is the tetranortriterpenoid azadirachtin and other limonoids. The effect of neem limonoids azadirachtin, salannin, deacetylgedunin, gedunin, 17-hydroxyazadiradione and deacetylnimbin on enzyme lactate dehydrogenase (LDH) activity of the rice leaffolder (RLF) Cnaphalocrocis medinalis (Lepidoptera: Pyralidae) larvae was investigated. There was a decrease in enzyme activity relative to the control at all concentrations tested. When fed a diet of rice leaves treated with neem limonoids in bioassays, gut tissue enzyme, LDH levels in rice leaffolder larvae are affected. These results indicate neem limonoids affect LDH activity. These effects are most pronounced in early instar larvae. Azadirachtin was the most potent in of all the limonoids in all experiments indicating strong enzyme inhibition. Clear dose–response relationships were established with respect to LDH activity. � 2005 Published by Elsevier Ltd.

Effective method for extraction of larvicidal component from leaves of Azadirachta indica and Artemisia annua Linn

Abstract: Leaves of Artemisia annua linn. and Azadirachta indica were extracted in petroleum ether and hexane respectively by different methods of extraction i.e. cold extraction, reflux extraction and soxhlet extraction. The crude extract obtained was tested against third instar larvae of Anopheles stephensi. On comparison of larval mortality of crude extract obtained by these three methods, both soxhlet and reflux extraction method showed 100% mortality at 200 ppm after 48 hr in case of A. annua. However LC50 (20 ppm) value of crude extract obtained by soxhlet extraction showed better results than reflux extraction (35 ppm) method after 72 hr. In case of A. indica, crude obtained by soxhlet showed 100% mortality (after 48 hr) at 250 ppm and LC50 of 69 ppm at 72 hr. Reflux extraction does not show any appreciable mortality even at 250 ppm concentration.

Clinical investigation of hypoglycemic effect of seeds of Azadirachta-inidca in type-2 (NIDDM) diabetes mellitus.

Abstract: The present study was designed to investigate clinically the hypoglycemic effect of seeds of Azadirachta indica in Type-2 diabetes mellitus. After assaying fasting plasma and urinary glucose, 10 patients of type-2 diabetes mellitus with no previous medication, 10 patients of type-2 diabetes mellitus taking oral hypoglycemic agents with history of inadequate control and six control subjects were given low (0.5 g tid) and high (2 g tid) doses of powdered part, aqueous extract and alcoholic extract of Azadirachta indica for 14 days. On 15th day blood and urine samples for glucose were taken. Based on results obtained it was found that Azadirachta indica has significant hypoglycemic activity in high dose and can be successfully combined with oral hypoglycemic agents in type-2 diabetic patients whose diabetes is not controlled by these agents.

Avaliação de produtos alternativos para controle da requeima do tomateiro

Abstract: The efficacy of alternative products to manage tomato (Lycopersicon esculentum) late blight, caused by Phytophthora infestans, was evaluated in three field trials (E) that compared: E1- [chili pepper (Capsicum chinense) + black pepper (Piper nigrum) + clove (Syzygium aromaticum) + turmeric (Curcuma longa) + garlic (Allium sativum) extracts]; (black pepper + clove + garlic extracts); and (clove + turmeric + garlic extracts); E2 - neem (Azadirachta indica) oil (0.5%), crude cow milk diluted in water (20% v/v), and Bordeaux mixture; E3 - homeopathic preparation (from tomato tissue infected with P. infestans - C30), the water-ethanol mixture, and Bordeaux mixture. All experiments had two controls: no sprays and metalaxyl. Severity at halfway through the epidemic (Y50); at the end of the epidemic (Ymax); area under disease progress curve (AUDPC); and disease progress rate (r) were estimated. None of the extracts reduced Y50, Ymax, AUDPC, or r values. Neem oil and Bordeaux mixture resulted in similar Y50 values (3% and 1%, respectively). Ymax (44%) in plots treated with neem was higher than in those treated with Bordeaux mixture (14%). Milk at 20% did not reduce Ymax. Values of r (0.161) and AUDPC (533) were lower with neem oil than in control (r = 0.211 and AUDPC = 1186) and similar to the Bordeaux mixture plots (r = 0.156 and AUDPC = 130). Values of r and AUDPC on plots treated with milk were similar to those in the control plots. There was no significant reduction of Y50, Ymax, AUDPC, or r values when plants were treated with homeopathic product. Bordeaux mixture was the most efficient treatment in controlling late blight. Neem oil is potentially useful. Integrated management must be implemented to keep late blight at acceptable levels on alternative tomato production systems.

In-vitro assay of some plant extracts against Fusarium oxysporum f. sp. lycopersici causal agent of tomato wilt

Abstract: The effect of crude extracts of neem (Azadirachta indica) leaf, neem seed and garlic (Allium sativum) at concentrations ranging from 5% to 30% of the material in 100 ml of Potato Dextrose Agar on mycelial growth of Fusarium oxysporum f. sp. lycopersici was assessed. All the extracts inhibited mycel- lial growth at various levels. Dry neem seed extract gavel 100% inhibition of mycelial growth. Fresh neem leaf extract reduced mycelial growth with increasing concentration while in garlic there were no differences in growth inhibition among the various concentrations used. However garlic extracts de- creased sporulation with increasing concentration and cultures grown on extract amended agar plates remained viable.

Mosquitocidal activities of malaysian plants

Abstract: ZARIDAH, M. Z., NOR AZAH, M. A. & ROHANI, A. 2006. Mosquitocidal activities of Malaysian plants. Extracts from about 30 species of plants in Malaysia were tested for their ability to kill the larvae or to repel or knock down the adults of Aedes aegypti, the vector mosquito for dengue and dengue hemorrhagic fever. Observation of mortality was made after 24 hours of exposure to the plant extract/essential oil to obtain the median lethal concentration (LC50) of the plant extract/essential oil tested. In repellency and knockdown effects of adult mosquitoes, median effective concentration (EC50) was obtained after each test. The three best extracts for killing larvae were the essential oils of Zanthoxylum acanthopodium stem, Aquilaria malaccensis wood and Pelargonium citrosum plant. For repelling adult mosquitoes, the most effective was the leaf essential oil of Cymbopogon nardus, followed by that of A. malaccensis. Knock-down ability was best with mosquito coils made from the seed kernel of Azadirachta indica, followed by the leaf of C. nardus and the wood of Fernandoa adenophylla.

Larvicidal properties of Lepidagathis alopecuroides and Azadirachta indica on Anopheles gambiae and Culex quinquefasciatus

Abstract: Comparative analysis of the larvicidal properties of aqueous extracts of leaves of Lepidagathis alopecuroides and Azadirachta indica (neem) was carried out on Anopheles gambiae and Culex quinquefasciatus. Assays showed that L. alopecuroides was more toxic to both larvae, while C. quinquefasciatus was more susceptible to extracts of both plants. For extracts from 500 mg of leaves in 1 L of water, the lethal time (LT50) for C. quinquefasciatus and A. gambiae with L. alopecuroides extract was in the ratio 1:4.5, while it was 1:21.8 with neem extract. No mortality was recorded in A. gambiae exposed to neem at all the concentrations until the emergence of the adult. The results suggest that L. alopecuroides is more potent than neem and could be developed as a cheap, effective and renewable resource that could be incorporated into the Roll Back Malaria program in Nigeria and other countries

Comparison of free radical scavenging activity of Siamese neem tree (Azadirachta indica A. Juss var. siamensis Valeton) leaf extracts prepared by different methods of extraction.

Abstract: Objective: The aim of this study was to investigate the antioxidant activity of the aqueous extracts of leaves of Siamese neem tree ( Azadirachta indica A. Juss var. siamensis Valeton) from several extracting and drying methods using 2,2-diphenyl-1-picrylhydrazyl (DPPH)scavenging assay. Materials and Methods: The leaves of Siamese neem tree were extracted using percolation, decoction, maceration, soxhlet extraction, freeze drying or spray drying methods. The extract was tested for antioxidant activity using DPPH-scavenging assay. Thin-layer chromatography of the extract from decoction was also investigated. Results: The freeze drying method gave the highest yield (51.50%, w/w) of crude extract, while decoction gave the most effective DPPH-scavenging activity (EC 50 : 31.4 � g/ml). Thin-layer chromatography analysis was used to screen the leaf extract obtained using decoction, and the chromatogram showed spots corresponding to quercetin and rutin fl avonoids which exhibited antioxidant activities (EC 50 : 2.29 and 34.67 � g/ ml, respectively). Conclusion: Siamese neem tree leaf extracts possessed free radical scavenging activity