Comprehensive Physicochemical Profiling and Characterization of Neem Plant Leaf Extracts: Insights for Pharmaceutical & Biomedical Applications

This study presents a comprehensive physicochemical analysis of neem plant leaf extracts with a focus on their potential applications in pharmaceutical and biomedical contexts. Utilizing the soxhlet extraction method with n-hexane as the solvent, the study investigated the quantitative and qualitative composition of neem leaf extracts in reference to concentrations. The results revealed a diverse array of compounds, including cyanogenic glycoside, cardiac glycoside, tannin, steroids, phytate, flavone, oxalate, rutin, lunamarin, catechin, spatein, naringin, resveratrol, kaempferol, flavonones, epicatechin, and epihedrine, with notable concentrations. Further analyses indicated shared physicochemical properties, such as carboxyl and hydroxyl groups. Qualitative assessments affirmed the presence of flavonoid and phenolic compounds, while FTIR analysis confirmed the existence of carboxyl and hydroxyl groups. These findings emphasize the potential use of neem leaves as pharmaceutical raw materials due to their antioxidant-rich content. Additionally, the study explored the density, viscosity, saponification value, and foaming power of neem leaf extracts, providing insights into their industrial applicability. GC-MS analyses highlighted the presence of significant chemical compounds, with potential therapeutic implications. Mineral analysis demonstrated essential elements for human and animal nutrition. This study underscores neem plant leaves’ multifaceted potential across pharmaceutical, herbal medicine, cosmetic, and functional food sectors. It lays a solid foundation for further research into the specific health benefits, offering valuable insights for harnessing neem leaves’ potential in innovative products and treatments.

NEEM计划2537.36m透底深冰芯的钻取与成果概述

NEEM(格陵兰北部Eemian冰芯钻取)计划是目前最重要的国际冰芯研究计划,来自14个国家超过300名的科学家参与,目标是获得130～115ka BP甚至更古老的Eemian间冰期的透底冰芯和气候信息;此冰芯长达2 537.36m,最后2m冰芯含有数十万年的基岩和其他物质.介绍了NEEM计划深冰芯的钻取背景和NEEM计划概况,以及NEEM计划获取的成果,并详述我国科学家在2010年度深冰芯钻取过程中取得的认识.

雄性大鼠输精管内注射Neem油的绝育效果:一种可代替输精管切除的方法

本文报道了一种可代替输精管切除术的方法,该方法是通过在输精管内一次性注入Neem油,从而达到长期节育的目的。

Neem油抗生育研究进展

Neem油的体内、外研究表明:它具理想的抗生育作用,取材容易、价格低廉、给药方法简单、避孕作用可逆、不影响内分泌和性功能,有希望发展成为一种有效的抗生育植物药,用于人类生育控制,本文综述了Neem油在这方面的研究现状。

Comparative efficacy of neem and dimethyl phthalate (DMP) against malaria vector,Anopheles stephensi (diptera:culicidae)

Malaria is one of the most important parasitic diseases in the world which is transmitted by the Anopheles mosquitoes. There are several methods for malaria control.One of them is application of repellents on skin in malarious area as an intergrated vectro management measures.This study evaluated two repellents of DMP as a synthtic and locally product of neem oil as a botanical repellent against Anopheles stephensi.The modified method of K & D was used for the tests.Probing/biting rates on the shaved belly of white rabbits were counted. ED50 and ED95 values were calculated by probit statistic software.Calculation of effective dose(ED50, ED90 ) on human volunteer and white rabbit was performed using regression line.Protection and failure time of DMP and neem oil was also determined.ED50 value of DMP and neem oil was determined as 0.0076 and 0. 159 mg/cm respectively on white rabit.The figures of ED90 value of DMP and neem oil was determined as 0. 046 and 1.388 mg/cm^2.DMP and neem oil showed repellency effects against An.stephensi on human volunteers with ED50 value of 0.0037 and 0.127 mg/cm^2 respectively.ED90 value of DMP was determined as 0. 032 mg/cm^2.neem oil exhibited a ED90 value of 1.066 mg/cm^2 on human volunteer.The protection time of 6-7 hours for DMP and 31 minute for neem oil was determined.The failure times for DMP and Neem was 9 hours and 65 minutes rspectively on human bait.Our results exhibited that plant-based repellent is generally less effective than synthetic repellents.However,use of locally made botanical materials would be of great advantages for personal protection against mosquito biting.

Antibacterial Activity of 9-Octadecanoic Acid-Hexadecanoic Acid-Tetrahydrofuran-3,4-Diyl Ester from Neem Oil

The 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester from neem oil was investigated for antibacterial activity against three bacterial strains viz., Staphylococcus aureus ATCC No. 25923, Escherichia coli ATCC No. 44102 and Salmonella sp. ATCC No. 50 041 in vitro. The minimum inhibitory concentration （MIC） and minimum bactericidal concentration （MBC） values of the 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester were determined by using the broth microdilution dilution （BMD） method at different concentrations ranging from 20 to 0.625 mg mL-1. Its time-inhibition curve against E. coli was also tested and showed that the MIC values for the bacterial strains S. aureus, E. coli and Salmonella sp. were 20, 5 and 10 mg mL-1, respectively. Its MBC values were 20, 20 and 10 mg mL-1, respectively. The antibacterial activity of 9-octadecanoic acid-hexadecanoic acid-tetrahydrofuran-3,4-diyl ester against three strain tested showed the relationship with time and concentration.

Comparative evaluation of modified neem leaf, neem leaf and woodash extracts on soil fertility improvement, growth and yields of maize (<i>Zea mays</i>L.) and watermelon (<i>Citrullus lanatus</i>) (Sole and Intercrop)

Two field experiments were carried out at Akure (7oN, 5o101E) in the rainforest zone of Nigeria in 2006 and 2007 to determine the effectiveness of neem leaf, woodash and modified neem leaf extracts as fertilizer sources in improving soil fertility, growth and yield of maize (Zea mays L) and watermelon (Citrulus lanatus) sole and intercrop. There were six treatments namely, poultry manure, neem leaf extract (sole), woodash extract, modified neem leaf (neem leaf + woodash), NPK 15-15-15 and a control (no fertilizer nor extract), replicated three times and arranged in a randomized complete block design (RCB). The extracts (neem leaf, wood ash and modified neem leaf) were applied at 1200 litres per hectare each, NPK 15-15-15 at 300 kg/ha and poultry was applied at 6t/ha. The results showed that there were significant increases (P 2O), K, Ca, Mg, Na, O.M, P and N compared to NPK 15-15-15 and neem leaf extract. For instance, modified neem leaf extract increased soil pH (H2O), K, Ca, Mg, Na, O.M, P and N by 12.4%, 32.8%, 25%, 23.7%, 19.32%, 17.24% and 20% respectively compared to neem leaf extract under intercrop plot. The high soil K/Ca, K/Mg and P/Mg ratios in the NPK 15-15-15 fertilizer treatment led to an imbalance in the supply of P, K, Ca and Mg nutrients to maize and watermelon crops. The least values for growth, yield and soil parameters were recorded under the control treatment. In these experiments, modified neem leaf extract (woodash + neem leaf extracts) applied at 1200 litres/ha was the most effective in improving soil fertility, growth and yield of maize and watermelon (sole and intercrop) and could substitute for 6 tons per hectare of poultry manure and 300kg/ha of NPK 15-15-15 fertilizer.

Breakdown of Azadirachtin A in a Tropical Soil Amended with Neem Leaves and Animal Manures

A field investigation was conducted to assess the breakdown of azadirachtin A in a tropical coastal savanna soil amended with neem leaves （NL） combined with poultry manure （PM） or cow dung （CD） using gas chromatography. Samples in polythene bags 15 cm long and 4.8 cm in diameter were randomly placed to a depth of 14 cm in the soil, and azadirachtin A concentration was assessed on days 0, 14, 28, 42, 56, 70, and 84. Azadirachtin A degradation in the soil followed first-order reaction kinetics with different half-lives obtained for varying combinations of the amendments. Higher neem amendment levels of 100 g gave shorter half-lives of azadirachtin A than the lower levels of 50 g. Within the 50 g NL group the additions of the poultry manure and the cow dung gave significantly shorter （P 〈0.05） half-lives of azadirachtin A than the sole neem amendment, whereas in the 100 g NL group only additions of 10 g CD and 10 g PM were significantly less （P 〈 0.05） than the sole neem amendment. Different changes resulting from the kind and quantity of animal manure added were observed in the half-lives of azadirachtin A. The 100 g NL group had significantly higher （P 〈0.05） moisture content, which, coupled with the likely differeaces in microbial biomass, could be the major factor responsible for variations in the half-llfe of the compound. Therefore, the quantity of the neem leaves applied and the addition of animal manure affected the breakdown of azadirachtin A in the soil amended with neem leaves.

Hardening Characteristics of Plain Carbon Steel and Ductile Cast Iron Using Neem Oil as Quenchant

The hardening characteristics of medium carbon steel and ductile cast iron using neem oil as quenching medium has been investigated. The samples were quenched to room temperature in Neem oil. To compare the effectiveness of the neem oil samples were also quenched in water and SAE engine oil the commercial quenchants. The microstructures and mechanical properties of the quenched samples were used to determine the quench severity of the neem oil. The result shows that hardness value of the medium carbon steel increased from 18.30HVN in the as-cast condition to 21.60, 20.30and 20.70HVN while that of ductile cast iron samples increased from 18.90HVN in the as-cast condition to 22.65, 20.30 and 21.30HVN for water, neem oil and SAE40 engine oil respectively. The as-received steel sample gave the highest impact strength value and water quenched sample gave the least impact strength. The impact strength of the medium carbon steel samples is 50.84, 41.35, 30.50 and 45.15 Joule and that of ductile iron is 2.71, 1.02, 0.68 and 1.70 Joule for as-cast condition, neem oil, water and SAE 40 engine oil quenched respectively. The microstructure of the samples quenched in the Neem oil revealed the formation of martensite. Hence, neem oil can be used where cooling severity less than that of water but greater than SAE 40 engine oil is required for hardening of plain carbon steels and ductile cast iron.

Comparative Isotherms Studies on Adsorptive Removal of Congo Red from Wastewater by Watermelon Rinds and Neem-Tree Leaves

Equilibrium adsorption studies for detoxification of Congo Red (CR) dye from single component model wastewater by powdered watermelon rinds and neem leaves adsorbents were carried out with the view to test the applicability of the adsorption process to Langmuir, Freundlich, Temkin, Dubinin-Radushkevich and Harkins-Jura isotherm models. The values of correlation coefficient, R2 (0.9359 - 0.9998), showed that all the experimental data fitted the linear plots of the tested isotherm models. Dubinin-Radushkevich’s monolayer maximum adsorption capacity qD (20.72 - 26.06 mg/g) is better than Langmuir’s qm (18.62 - 24.75 mg/g) for both adsorbents with the capacities higher for adsorption on watermelon rind than on neem leaves. Values of Langmuir separation factor (RL) suggest unfavourable adsorption processes (i.e. chemisorption) of the dye on both the adsorbents, while Freundlich constant (nF) indicates unfavourable process only for CR adsorption onto neem leaves. The Dubinin-Radushkevich’s mean free energy of adsorption, E (0.29 - 0.32 kJ/mol), suggests physical adsorption processes. Values for Temkin’s heat of adsorption, bT (-0.95 to 0.74 kJ/mol), also show physical adsorption process.

Therapeutic Potential of Neem Synthesized Silver Nanoparticles on Human Gastric Cancer Cells in Vitro

Nanotechnology has shown significant promise in development of drugs and drug delivery systems that can overcome all limitations and address urgent needs to improve efficacy of diagnosis and therapy of various diseases including cancer. The functionalization with neem compounds as synthesis and capping agent had shown very high anticancer activities against Gastric cancer cells in vitro. The biochemical factors like albumin, glucose, and DNA concentrations were modulated along with Protease inhibitor and Catalase activates, the various cancer specific proteins like p53, GRD 70 - 78 kDa and other proteins of sizes 35 - 40 kDa corresponding to H+K+ATPase protein etc. The apoptic activity and antiproliferative activity were demonstrated with Gastric cancer cells in vitro.

High-resolution mass spectrometric characterization of dissolved organic matter from warm and cold periods in the NEEM ice core

Dissolved organic matter(DOM) is an important component of ice cores but is currently poorly characterized. DOM from one Holocene sample(HS, aged at 1600–4500 B.P.) and one Last Glacial Maximum sample(LS, aged at 21000–25000 B.P.) from the North Greenland Eemian Ice Drilling(NEEM) ice core were analyzed by ultra-high resolution Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS). CHO compounds contributed 50% of the compounds identified in negative-ionization mode in these two samples, with significant contributions from organic N, S, and P compounds, likely suggesting that marine DOM was an important source in these samples. Overall, the chemical compositions are similar between these two samples, suggesting their consistent DOM sources. However, subtle differences in the DOM between these two samples are apparent and could indicate differences in source strength or chemistry occurring through both pre-and post-depositional processes. For example, higher relative amounts of condensed carbon compounds in the HS DOM(5%), compared to the LS DOM(2%), suggest potentially important contributions from terrestrial sources. Greater incorporation of P in the observed DOM in the LS DOM(22%), compared to the HS DOM(13%), indicate more active microbiological processes that likely contribute to phosphorus incorporation into the DOM pool. Although these two samples present only a preliminary analysis of DOM in glacial/interglacial periods, the data indicate a need to expand the analysis into a broader range of ice-core samples, geographical locations, and glacial/interglacial periods.

Selected physical and chemical properties of mechanically extracted neem seed oil sourced as a preservative for ligno-cellulose in south-western Nigeria

Most of the seeds produced by neem （Azadirachta indica A. Juss） trees in Nigeria are currently underutilized. Hence, relevant literature provides only limited information conceming many of the seed oils from this country, especially where it concems the potential applications of these oils as preservatives for ligno-cellulose against bio-deterioration. Using standard procedures therefore, this study was carried out to evaluate and document selected physical and chemical properties of neem seed oil （NSO）, mechanically extracted using a cold press at 31.03 N-mm^-2 pressure and a room temperature of 25 ± 2℃. The results show that oil yield was 38.42% with a specific gravity of 0.91 ± 0.01. The amount of acid was 18.24 ± 1.31 mg KOH.g^-1 and that of iodine 93.12 ± 2.01 g-100 g^- 1, while saponification and peroxide values were 172.88 ± 2.06 and 1.42 ± 0.04 mg·g^-1 respectively. The implication of the values obtained, particularly those for the chemical properties, as they concern the potential application of NSO as a preservative for ligno-eellulose, is likely that it may be useful in this regard since the values may support some of the documented anti-microbial properties of the oil, although other physical and chemical properties that may affect this potential are recommended for investigations. Conclusions and other recommendations follow in line with the results of the study.

Neem (Azadirachta indica) Leaves for Removal of Organic Pollutants

Neem (Azadirachta indica) leaves was employed in a batch adsorption technique for the detoxification of congo red (CR) and methyl orange (MO) dyes from a single component model wastewater. The adsorption efficiency of the leave was judged based on changes of parameters like agitation time, adsorbent dosage, adsorbent particle size, and adsorbate initial concentration and pH. Adsorbate concentration during the adsorption process was monitored using T60-U UV-Visible spectrometer from TG Instruments. While FTIR and SEM were employed to study the surface functional group and morphological changes of the adsorbent before and after the adsorption process. Percent adsorption increased with increase in agitation time (5 - 240 minutes), adsorbent dosage (0.1 - 0.5 g), initial concentration (100 - 300mg/L), and with decrease in particle size (≥75 μm to ≤300 μm) of adsorbent. The adsorption processes were found to be pH-dependent, increasing or decreasing in acidic (pH 2 - 6) or alkaline (pH 8 - 12) range over the studied pH (2 - 12) range. The correlation coefficient (R2 – values) ranging from 0.9359 - 0.9998 shows good agreement of the experimental data for all the tested isotherms. The monolayer maximum adsorption capacity for Langmuir’s qm (18.62 - 24.75mg/g) and Dubinin-Radushkevich, qD (20.72 - 26.06mg/g) are comparable. Both Langmuir’s separation factor (RL) and Freundlich constant (nF) suggests unfavourable adsorption of the dyes onto the adsorbent. The mean free energy of adsorption, ?? (79.06 - 316.23 J/mol) calculated from Dubinin-Radushkevich equation suggest a physical adsorption. Restricted range of values for heat of adsorption, bT (?946.9 to 737.4 J/mol), was obtained from Temkin equation. Reduction in band intensities and vibrational changes observed in FTIR spectra indicate possible involvement of carbonyl (-C=O), carboxyl (-COOH), hydroxyl alcoholic (-OH) and amino (-NH2) functional groups on the adsorbents’ surfaces during the adsorption and interaction with the sulfonic acid groups (-SO3H) on the adsorbate molecules. The difference in irregular and porous texture surface morphology of fresh and dye-loaded adsorbents characterized the adsorption of the dyes by neem leaves. The study shows that neem leaves are potential alternative low-cost adsorbents for the effective removal of Congo red (CR) and Methyl orange (MO) from wastewater.

In vitro activity of neem oil [Azadirachta indica A. Juss (Meliaceae)] on Aspergillus flavus growth, sporulation, viability of spores, morphology and Aflatoxins B1 and B2 production

The effectiveness of neem (Azadiracta indica) oil on the growth, morphology, sporulation, viability of spores, aflatoxin B1 and B2 production by A. flavus on Yeast Extract-Sucrose medium was determined. Neem oil inhibited the fungal growth (i.e. mycelia dry weight, diameter of colony and growth rate) on solid media at concentrations from 0.5 to 5.0% v/v, although it significantly increased sporulation in the same conditions. Spores obtained from cultures grown without neem oil reduced germination when incubated in a neem oil supplemented medium. Colonies grown on solid media and in submerged cultures in the presence of neem oil exhibited morphological alterations, including granular cytoplasm, atypical hyphae branching pattern, abnormal and undifferentiated conidiophores. High Performance Liquid Chromatography was used to measure aflatoxins. In submerged cultures, neem oil at concentrations from 0.5 to 4.0% v/v caused approximately 95% inhibition in Aflatoxin B1 and B2. On other hand, these conditions failed to suppress fungal growth. Current research emphasized that neem oil was not fungistatic or fungicidal, but exhibited anti-aflatoxigenic activity.

Effect of a 5% Neem Solution on the Presence of Ticks in Cattle in Two Locations in Jalisco, Mexico

The objective of this work was to evaluate the effect of a 5% neem extract on the presence of ticks. Forty creole cattle were used, divided into four groups: 2 experimental and 2 controls, in the towns of Cocula and El Chante, Jalisco. The tick count was by direct palpation, and with an acarometer (25 cm2). Eight body regions were evaluated: neck, thorax, flank and thigh, left and right. At zero time, after the initial tick count, it was applied by spraying and once, the 5% neem extract, at a dose of 10 ml/L. Ticks were quantified at 7, 14, 21, 28, 35 and 42 days post-treatment. The data were subjected to descriptive statistical analysis and Sum of Kruskal-Wallis Ranges (α = 0.05) (SigmaStat 3.1). In Cocula, at zero time, the average of ticks was in neck 32, in thorax 64, in flanks 96 and in thighs 129 (average per animal 323 ticks). In subsequent sampling, the average decreased in the experimental group to 1 or 4 parasites. In “El Chante”, an average of 60 ticks was found at the time of the neck, in the thorax 121, in flanks 181 and in thighs 242 (average per animal 600 ticks). In subsequent sampling, the average decreased in the experimental group, with averages of 1 to 4. Statistical differences (p ≤ 0.001) were found between the groups. It can be concluded that 5% neem extract has a repellent and tick effect in cattle for at least 42 days.

Evaluation of the Repellency Effect of Neem (<i>Melia azedarach</i>) Plant Extracts Based on the Mittler &Dadd Method

Using insect repellent compounds, especially during the warm months, provides comfort for people and preventsspreading of the insect-borne diseases such as dengue fever, malaria and Leishmaniasis. Poisons derived from plants contain alkaloids, glucoside and some essential oils that are taken from plant tissues. They may have repellent and insecticide properties with little toxicity to humans and animals. In this study, Neem plant1 from Bandar Abbas city was used to assess its repellency effect. Therefore, after drying and powdering using maceration method, final Neem extract concentration of 5%, 10% and 20% was provided. Mittler & Dadd methodology was hired to assess this effect. In this method, the antifeedant effect of the?Neem plant extract was evaluated on cabbage-feeding aphid (Brevicoryne brassicae). After 24 and 48 hours, the reduced numbers of feces spot of aphids showed that the ingestion of the provided food mixture contained Neem plant extract was significantly decreased. Here it was shown that the Neem plant extract could be used as an efficient repellent.

Animal Manure, Neem Cake, Biochar, Vermicompost or Urea: Choosing the Better Option for <i>Spinacia oleracea</i>Growth and Soil Fertility

Production of safe food through organic farming while maintaining soil sustainability is the crucial challenge of recent time. As such a pot experiment was conducted using animal manure (TAM), neem-cake (TNC), vermicompost (TVC), biochar (TBC) and urea (TU) with control (TC) to assess their capacity to stimulate Spinacia oleracea growth under field condition and their impact on soil fertility. Six treatments: TC, TAM, TNC, TVC, TBC, TU with three replications were used in completely randomized design (CRD). All the plant growth parameters were measured at regular interval up to maturity. Complete chemical analysis of plant tissue, amendments and soil was carried out. Nitrogen use efficiency (NUE) under different treatments was calculated at 45 and 60 days. All the treatments showed statistically significant (P < 0.001) increase in yield over control and urea. The highest plant height (24 cm), leaf area index (0.154), and dry weight (1254 kg/ha) were found at TNC which increased respectively 132%, 258%, 450% over control and 125%, 431%, 448% over urea. TVC was the second best treatment followed by TBC for plant growth. NUE was significantly (P < 0.001) higher in treatment TVC than any other treatments and was higher at maturity than vegetative state. TNC had lower NUE than TVC and TBC but the inherent N content was higher in TNC than TVC and TBC. Uptake of certain macro nutrients showed significant (P < 0.05) positive correlation with plant growth parameters i.e., plant height with P (R = 0.887);leaf area with N (R = 0.957) and P (R = 0.985);dry weight with N (R = 0.996), P (R = 0.994) and K (R = 0.860). Significant (P < 0.001) increase in post-harvest soil C and CEC content was found with all the treatments. The highest availability of N, P and S was observed under treatment TNC. For short duration crop like spinach, TNC is the best option followed by TVC as they release nutrient quickly than TBC and TAM.

Evaluation of Neem-based Compound Fertilizer for Crop Production in Samaru, Moist Savanna of Nigeria

Nutrient mining is one of the major threats facing crop production in Africa and inputs of nutrients are required to overcome this constraint. Greenhouse and field trials were conducted to investigate the effect of sole and combined applications of neem-based and conventional compound （NPK 15-15-15） fertilizers on five crops. In another set of treatments, a factorial combination of the neem fertilizer and urea at 30, 60 and 90 kg N ha-1 was applied to maize, millet and sorghum in the field in a randomized complete block design. The results obtained on cowpea and soybean showed that application of 20 kg N hal from the neem-based compound fertilizer produced both grain and haulm yields that were comparable to what was obtained with the application of 30 kg N ha1 from the conventional fertilizer. Based on maize performance, combined application of neem-based and NPK in ratio 0.25：0.75 respectively gave significantly （P 〈 0.01） higher plant height, stem girth, shoot and dry weight compared to other treatment combinations. The causes of the interactions between the two fertilizer sources resulting in added benefits from their mixed rather than sole application could be attributed to improvement in phosphorus availability and other soil conditions.