Azadirachta Indica Leaf Powder Research Articles

Removal of fast green dye (C.I. 42053) from an aqueous solution using Azadirachta indica leaf powder as a low- cost adsorbent

Azadirachta indica (neem) leaf powder was used as an adsorbent for the removal of textile dye from aqueous solution. The adsorption of dye on A. indica was found to be dependent on contact time, dye concentration and amount of adsorbent. Spectrophotometric technique was used for the measurement of concentration of dye before and after adsorption. The removal data were fitted on Langmuir and Freundlich adsorption isotherm equations. The values of their corresponding constants were determined from the slope and intercepts of their respective plots. The adsorption isotherm data will employ to calculate the thermodynamic parameters like (
G) Gibb’s free energy, (
H) change in enthalpy and (
S) entropy. The values of percent removal and KD for Fast green dye on neem leaf powder was also calculated at temperatures ranging from 303-318 K.

Azadirachta indica leaf powder as a biosorbent for Ni(II) in aqueous medium

Azadirachta indica leaves are converted to a fine powder for use as a biosorbent for the removal of metal ions in aqueous solution. In this work, the adsorptive interactions between Ni(II) and the powder were studied under a variety of conditions involving variations in pH, Ni(II) concentration, biosorbent amount, interaction time and temperature, all in single batch processes. The experimental data have been interpreted on the basis of existing mathematical models of equilibrium kinetics and thermodynamics. The biosorption of Ni(II) increased in the pH range of 2.0–5.0 with ∼92.6% adsorption at pH 5.0 for the highest amount of the biosorbent (4 g/L). The biosorption followed second-order kinetics and intra-particle diffusion was likely to have significant influence in controlling the process. The Langmuir monolayer adsorption capacity varied from 2.4 to 9.1 mg/g and the equilibrium coefficient from 1.09 to 2.78 L/g with strong indication that the Ni(II) ions were held on the biosorbent surface by formation of an adsorption complex. The thermodynamic parameters showed the process to be exothermic in nature supported by appropriate ranges of values of enthalpy change, entropy change and Gibbs energy change.

Biosorption of Commercial Dyes on Azadirachta indica Leaf Powder: A Case Study with a Basic Dye Rhodamine B

Biosorbents, collected and prepared from nature, are most widely used for this purpose. In the present work, removal of a basic dye called Rhodamine B from aqueous solution by adsorption onto a biosorbent, Azadirachta indica (neem) leaf powder (AILP), was investigated. Removal was tested in a batch process with concentration of dye solution, AILP load, pH, temperature, and contact time as the working variables. The adsorption was favored by an acidic pH range and was best described by a second-order rate equation. The experimental data were verified by fitting into both Freundlich and Langmuir isotherms. Thermodynamically, the process was found to be exothermic accompanied by a decrease in entropy and increase in Gibbs energy as the temperature of adsorption was increased from 303 to 333 K. The effect of solution temperature, and the determination of the thermodynamic parameters of adsorption of Rhodamine B (RB) on AILP enthalpy of activation, entropy of activation, and free energy of activation, on the adsorption rates are important in understanding the adsorption mechanism. The rate and the transport/kinetic processes of dye adsorption onto the adsorbents are described by applying various kinetic adsorption models. This would lead to a better understanding of the mechanisms controlling the adsorption rate. The pseudo-second-order model was the best choice among all the kinetic models to describe the adsorption behavior of RB onto AILP, suggesting that the adsorption mechanism might be a chemisorption process. The negative value of the enthalpy change suggested that the rise in the solution temperature did not favor RB adsorption onto AILP.

Interactions of Pb(II), Cd(II) and Cr(VI) with Neem (Azadirachta indica) leaf powder: kinetics and thermodynamics

Neem leaf powder (NLP) is made from the leaves of the Neem tree (Azadirachta indica) for removing Pb(II), Cd(II) and Cr(VI) from water. The powder (surface area 21.45 m²/g), was used at pH ∼7.0 and pseudo first and second orders, Elovich equation, intra-particle and liquid film diffusion models were used to test the kinetics. The interactions mostly followed a second-order model involving transfer of the cations from the surrounding liquid film to the surface of the adsorbent particles. The interactions were exothermic and spontaneous. Enthalpy, entropy and Gibbs energy changes show a high potential of NLP as a biosorbent for metal ions.

Azadirachta indica A. Juss Induced Changes in Spermatogenic Pattern in Albino Rats

Objective: The leaves of Azadirachta indica A. Juss was tested to find the antispermatogenicity in seminiferious epithelium of rats. Materials and methods: Male albino rats were administered orally (by gavage), 100 mg/ body weight Azadirachta indica leaf powder with or without testosterone (IM). Suitable controls were maintained. Results: Damaged seminiferous tubules and abundance of vacuoles of varying size were observed in Azadirachta indica treated rats. The germ cells showed overall decrease in cytoplasmic ground substance. Leydig cells exhibited characteristics of degeneration with condensed nuclei. Total count of spermatocytes, spermatids and Leydig cells were reduced. The cell and nuclear diameter of spermatogonia, spermatocytes, spermatids and Leydig cells were also reduced. Conclusion: From the results obtained, it can be observed that Azadirachta indica effects on the testis are possibly due to gonadotrophic hormone deficiency, caused directly or indirectly. The probable mode of antiandrogenic and antispermatogenic actions of the medicinal plant is discussed.

Azadirachta indica (Neem) leaf powder as a biosorbent for removal of Cd(II) from aqueous medium

A biosorbent, Neem leaf powder (NLP), was prepared from the mature leaves of the Azadirachta indica (Neem) tree by initial cleaning, drying, grinding, washing to remove pigments and redrying. The powder was characterized with respect to specific surface area (21.45 m 2 g −1), surface topography and surface functional groups and the material was used as an adsorbent in a batch process to remove Cd(II) from aqueous medium under conditions of different concentrations, NLP loadings, pH, agitation time and temperature. Adsorption increased from 8.8% at pH 4.0 to 70.0% at pH 7.0 and 93.6% at pH 9.5, the higher values in alkaline medium being due to removal by precipitation. The adsorption was very fast initially and maximum adsorption was observed within 300 min of agitation. The kinetics of the interactions was tested with pseudo first order Lagergren equation (mean k 1 = 1.2 × 10 −2 min −1), simple second order kinetics (mean k 2 = 1.34 × 10 −3 g mg −1 min −1), Elovich equation, liquid film diffusion model (mean k = 1.39 × 10 −2 min −1) and intra-particle diffusion mechanism. The adsorption data gave good fits with Langmuir and Freundlich isotherms and yielded Langmuir monolayer capacity of 158 mg g −1 for the NLP and Freundlich adsorption capacity of 18.7 L g −1. A 2.0 g of NLP could remove 86% of Cd(II) at 293 K from a solution containing 158.8 mg Cd(II) per litre. The mean values of the thermodynamic parameters, Δ H, Δ S and Δ G, at 293 K were −73.7 kJ mol −1, −0.24 J mol −1 K −1 and −3.63 kJ mol −1, respectively, showing the adsorption process to be thermodynamically favourable. The results have established good potentiality for the Neem leaf powder to be used as a biosorbent for Cd(II).

CHANGES IN SERTOLI CELLS OF ALBINO RATS INDUCED BY Azadirachta indica A. Juss LEAVES

Azadirachta indica leaf powder, 0.05 mg testosterone, or combined leaf powder + testosterone was administered for 48 days to different groups of 3-month-old albino rats. Twenty-four hours after the final dose, the treated animals received mild ether anesthesia and the testes were dissected out and processed for light and electron microscope studies. Animals treated with A. indica leaf powder showed damaged tubules and exhibited an abundance of vacuoles, including inter-cellular spaces and intra-epithelial vacuoles of varying size in the cytoplasm of Sertoli cells. Upon treatment with A. indica leaf powder, bridges between Sertoli cells-Sertoli cells and Sertoli cell-germ cells were disturbed, coupled with changes in the Sertoli cells and cytoplasm along with its organelles. We suggest that the anti-androgenic property of A. indica leaves probably affects Sertoli cells, followed by the degeneration of germ cells, resulting in exfoliation.

Pre-storage treatments to improve viability in Casuarina equisetifolia seeds

Casuraina equisetifolia is an important plantation tree which is propagated through seed. Seeds loose their initial viability of 40-50% rapidly and reach 5% at the end of one year. Keeping these in view, an attempt was made to develop a technology to slow down the speed of seed deterioration using chemicals and botanicals viz., neem (Azadirachta indica), turmeric (Curcuma longa), acorus (Acorus calamus), arappu (Albizzia amara), acetyl salicylic acid and halogenation. Evaluations were made at bimonthly intervals on physiological potential and enzyme activity of seeds viz., amylase, catalase, peroxidase and superoxide dismutase. The results indicated that neem (Azadirachta indica) leaf powder and acetyl salicilic acid is capable of sustaining the activity of the enzymes during the storage period which can inturn maintain the seed germination potential and seedling vigour as well.

Adsorption of Chromium (VI) on Azadirachta Indica (Neem) Leaf Powder

A novel adsorbent was developed from mature leaves of the Neem tree (Azadirachta Indica) for removing metal ions from water. The adsorbent, in the form of fine powder, was found to be very effective in removing chromium (VI) from aqueous solution. The adsorption was carried out in a batch process taking different concentrations of the metal ion in aqueous solution with variation in adsorbent amount, pH, agitation time and temperature. The suitability of the adsorbent was tested with Langmuir and Freundlich isotherms and with various equilibrium kinetic data. A small amount of the Neem Leaf Powder (NLP) (1.6 g dm−3) could remove as much as 87% of Cr (VI) in 300 min from a solution of concentration 14.1 mg dm−3 at 300 K. The optimum range of pH for the adsorption process was 4.5–7.5 and since the natural pH of the Cr (VI) solution was 5.5, no addition of acid or alkali was necessary for achieving maximum adsorption. The adsorption coefficients indicated a high potentiality for the NLP to be used as an adsorbent for removing Cr (VI) from water.

Kinetics and thermodynamics of Methylene Blue adsorption on Neem ( Azadirachta indica) leaf powder

The dye, Methylene Blue, was adsorbed on an adsorbent prepared from mature leaves of the Neem tree ( Azadirachta indica). A batch adsorption study was carried out with variable adsorbate concentration, adsorbent amount, pH, and temperature. Ninety-three percent of the dye could be removed by 2 g of the Neem leaf powder from 1 L of an aqueous solution containing 25 mg of the dye at 300 K. The adsorption followed pseudo first order kinetics with a mean rate constant of 3.73 × 10 −3 min −1 and an intra-particle diffusion rate constant of 6.36 × 10 −2 mg g −1 min −0.5. A possible mechanism of adsorption was suggested on the basis of concurrently operating surface adsorption and pore diffusion. The experimental data yielded excellent fits with Langmuir and Freundlich isotherm equations. The Langmuir monolayer capacity had a mean value of 8.76 mg g −1. The adsorption of the dye was endothermic in nature (Δ H: 4.62–16.74 kJ mol −1) and was accompanied by an increase in entropy (Δ S: 54.22–90.23 J mol −1 K −1) and a decrease in Gibbs energy (Δ G: −10.33 to −13.62 kJ mol −1 in the temperature range of 300–330 K). The results indicated that the dye, Methylene Blue, strongly interacts with a biomass-based adsorbent, the Neem leaf powder.

Adsorption of Pb(II) from aqueous solution by Azadirachta indica (Neem) leaf powder

An adsorbent was developed from the mature leaves of the Neem ( Azadirachta indica) tree for removing Pb(II) from water. Adsorption was carried out in a batch process with several different concentrations of Pb(II) by varying amount of adsorbent, pH, agitation time and temperature. The uptake of the metal was very fast initially, but gradually slowed down indicating penetration into the interior of the adsorbent particles. Both first-order and second-order kinetics were tested and it was found that the latter gave a better explanation. The experimental data closely followed both Langmuir and Freundlich isotherms. The adsorbent had a considerably high Langmuir monolayer capacity of 300 mg/g. A small amount of the adsorbent (1.2 g/L) could remove as much as 93% of Pb(II) in 300 min from a solution of concentration 100 mg/L at 300 K. The adsorption continuously increased in the pH range of 2.0–7.0, beyond which the adsorption could not be carried out due to the precipitation of the metal. The adsorption was exothermic at ambient temperature and the computation of the parameters, Δ H, Δ S and Δ G, indicated the interactions to be thermodynamically favourable.

Azadirachta indica leaf powder as an effective biosorbent for dyes: a case study with aqueous Congo Red solutions

In the present work, the leaves of Azadirachta indica (locally known as the Neem tree) in the form of a powder were investigated as a biosorbent of dyes taking aqueous Congo Red solution as a model system. The sorbent was made from mature Neem leaves and was investigated in a batch reactor under variable system parameters such as concentration of the aqueous dye solution, agitation time, adsorbent amount, pH, and temperature. An amount of 0.6 g of the Neem leaf powder (NLP) per litre could remove 52.0–99.0% of the dye from an aqueous solution of concentration 2.87×10−2 mmol l−1 with the agitation time increasing from 60 to 300 min. The interactions were tested with respect to both pseudo first-order and second-order reaction kinetics; the latter was found to be more suitable. Considerable intra-particle diffusion was found to occur simultaneously. The sorption process was in conformity with Langmuir and Freundlich isotherms yielding values of the adsorption coefficients in the following ranges: Freundlich n: 0.12–0.19, Kf: 0.1039–0.2648 L g−1; Langmuir qm: 41.24–128.26 g kg−1, b: 443.3–1898.0 l mmol−1, which supported favourable adsorption. The Langmuir monolayer capacity (qm) was high and the values of the coefficient b indicated the equilibrium, dye+NLP=dye⋯NLP being shifted overwhelmingly towards adsorption. Thermodynamically, the sorption process was exothermic with an average heat of adsorption of −12.75 kJ mol−1. The spontaneity of the sorption process was also confirmed by the favourable values of Gibbs energy (mean values: −1.09 to −1.81 kJ mol−1) and entropy of adsorption (range: −18.97 to −56.32 J mol−1 K−1). The results point to the effectiveness of the Neem leaf powder as a biosorbent for removing dyes like Congo Red from water.

Azadirachta indica leaf powder as an effective biosorbent for dyes: a case study with aqueous Congo Red solutions

In the present work, the leaves of Azadirachta indica (locally known as the Neem tree) in the form of a powder were investigated as a biosorbent of dyes taking aqueous Congo Red solution as a model system. The sorbent was made from mature Neem leaves and was investigated in a batch reactor under variable system parameters such as concentration of the aqueous dye solution, agitation time, adsorbent amount, pH, and temperature. An amount of 0.6 g of the Neem leaf powder (NLP) per litre could remove 52.0–99.0% of the dye from an aqueous solution of concentration 2.87×10 −2 mmol l −1 with the agitation time increasing from 60 to 300 min. The interactions were tested with respect to both pseudo first-order and second-order reaction kinetics; the latter was found to be more suitable. Considerable intra-particle diffusion was found to occur simultaneously. The sorption process was in conformity with Langmuir and Freundlich isotherms yielding values of the adsorption coefficients in the following ranges: Freundlich n: 0.12–0.19, K f: 0.1039–0.2648 L g −1; Langmuir q m: 41.24–128.26 g kg −1, b: 443.3–1898.0 l mmol −1, which supported favourable adsorption. The Langmuir monolayer capacity ( q m) was high and the values of the coefficient b indicated the equilibrium, dye+NLP=dye⋯NLP being shifted overwhelmingly towards adsorption. Thermodynamically, the sorption process was exothermic with an average heat of adsorption of −12.75 kJ mol −1. The spontaneity of the sorption process was also confirmed by the favourable values of Gibbs energy (mean values: −1.09 to −1.81 kJ mol −1) and entropy of adsorption (range: −18.97 to −56.32 J mol −1 K −1). The results point to the effectiveness of the Neem leaf powder as a biosorbent for removing dyes like Congo Red from water.

Efficiency and profitability of an IPM package against insects, blast, and nematodes in irrigated rice

In Burkina Faso, major biotic constraints to rice production in irrigated conditions include insects, diseases, and nematodes. Lepidopterous stem borers (Chilo zacconius, C. diffusilineus, Maliarpha separatella, and Sesamia calamistis) can cause up to 33% yield losses (Dakouo et al 1991). A 1% increase in damage of the African rice gall midge is correlated with a 2% yield loss (Nacro et al 1996). Pot trials showed a yield loss of 30% caused by rice root nematode Hirschmaniella spinicaudata (Thio 1992). Rice blast (caused by Pyricularia oryzae) causes yield losses with an estimated value of more than US$10 million in West Africa (WARDA 1995). Pest control in irrigated rice still largely depends on the use of chemicals without meeting the necessary criteria of efficiency and profitability for small-scale farmers. Therefore, a cost-effective integrated pest management (IPM) package was developed by a multidisciplinary team to minimize reliance on toxic and expensive chemicals. This IPM package combines the use of local natural products made of organic manure (5 t ha-1) against nematodes, rice straw ash (2.5 t ha-1) against blast, dry neem (Azadirachta indica) leaf powder against nematodes, and alcoholic extracts of neem seed powder (200 g into 0.25 L of alcohol and 0.75 L of water) against insects. The efficiency and profitability of the package were evaluated during the 2000 wet season at two irrigated rice schemes, Banzon and Karfiguela, near Bobo-Dioulasso, southwest Burkina. Its efficiency was optimized with the use of a rice gall midge-tolerant variety, BW 348-1. The IPM package (T3) was compared with two other treatments, T1 and T2. The first treatment (T1) was the control with no products against pests. T2 was a reference chemical treatment combining the insecticide Basudin (diazinon) at 1,000 g ai ha-1 in foliar sprays at 20, 40, and 60 d after transplanting (DAT), the nematicide Basamid (dazomet) at 100 kg ha-1 (incorporated into the soil 14 d before transplanting), and the fungicide Kitazin (di-isopropyl-sbenzil-thiophosphate) in a foliar spray at 720 g ai ha-1 at panicle emergence. The experimental design was a completely randomized block with three treatments and four replications, a plot size of 60 m2 (10 6 m), and plant density of 25 25 cm. Insect damage (deadhearts and onion shoots) was assessed at 40, 60, 80, and 100 DAT. Foliar blast was evaluated at 35, 49, and 63 DAT and neck blast incidence at 15 and 30 d after panicle emergence (DAPE). Nematode populations were estimated at the time of Basamid application—before transplanting and at 30, 60, 90, and 120 DAT.

Plants with insecticidal activities against four major insect pests in Pakistan

Abstract Local flora was screened for pesticidal activity against insect pests of field crops, Aesculus indica (flower and leaf) extract was found effective (up to 75% mortality) against sugarcane mealybug (Saccharicoccus sacchari). Schinus molli (leaf), and Aesculus Indica (leaf and flower) extract caused significant (60–70%) mortality in yellow rice stem borer (Schirpophaga incertulas) larvae. Azadirachta indica leaf powder fed to chickpea pod borer (Heliothis armigera) caused failure in pupation and adult emergence. Addition of Azadirachta Indica and Broussentia papyrifera to artificial diet restricted the adult emergence in Heliothis armigera. Similarly, prolonged larval period (21 days compared to 14 in control), delayed pupation and deformed adult formation resulted after treatment with Azadirachta indica (leaf) and Melia azedarech (fruit) powder. Significant mortality (60–90%) was observed in sugarcane pyrilla (Pyrilla perpusilla) adults treated with Azadirachta indica, Dryopteris ramosa and Schinu...