Search

Heavy metal contamination of water is a burning global issue, and enormous importance has been given on easily applicable watertreatment methods namely adsorption. However, search for an efficient and reusable adsorbent is ever-evolving. In this study, activated carbon from highly ligno-cellulosic jute stick (JS-AC), the agricultural by-product of jute (Corchorus olitorius), was evaluated as a new adsorbent for removing cadmium (Cd) from the aqueous medium. The direct and interaction effects of four independent adsorption factors namely, initial Cd(II) concentration (20–100 mg/L), adsorbent dose (0.5–1 g/L), solution pH (3–7), and time (30–180 min) were investigated by applying response surface methodology (RSM). A 24 Box-Behnken matrix model with 3 centre points indicated that the maximum % Cd(II) removal was achieved at the initial concentration, dose, pH and time of 60.87 mg/L, 0.5 g/L, 7, and 30 min, respectively. The adsorption equilibrium was investigated by applying Freundlich, Langmuir, Temkin, and Jovanoic isotherm models while Langmuir isotherm exhibited the best fit (R2 = 0.99). The maximum Cd(II) adsorption capacity value of JS-AC was 73.53 mg/g. Finally, JS-AC was regenerated with 0.1M HNO3 as the desorption medium and reused for five successive cycles. This study indicated that jute stick, the under-utilised agro-residue of a cash crop, could be converted into a valuable product like JS-AC which offers immense application potential as an efficient and reusable adsorbent to treat Cd(II) contaminated aqueous medium before releasing in the environment. [ABSTRACT FROM AUTHOR]

An attempt has been made to dissolve lac in methanol / sodium hydroxide solution and to use this lac solution as a coupling agent for jute fabric. Lac treated jute fabric has been used to reinforce the unsaturated polyester resin (USP). Flexural strength and inter-laminar shear strength (ILSS) of lac modified jute/USP biocomposite have been evaluated and then compared with sodium hydroxide treated jute as well as untreated jute based biocomposites. Lac treated jute fabric shows higher flexural properties of the biocomposite than that of untreated jute fabric, which infers that lac acts as a good compatibliser between jute fibre and USP. Lac treatment on jute fabric enhances the flexural properties of biocomposite better in alkaline medium than in solvent medium. It is concluded that lac treatment can be used to improve the flexural and ILSS properties of jute / thermoset resin based biocomposite. [ABSTRACT FROM AUTHOR]

With the advancements in the field of biotechnology and genetic engineering a totally new dimension have been developed. It had become possible, by genetic manipulation of genes obtained from one species to another to produce transgenics -having resistance to both biotic and abiotic stresses, which have been also proved to yield higher crop productivity. Proper standard to regulate the genetically modified foods have not been developed yet, although bioengineers have begun creating hundreds of new genetically engineered crops. Their impact on human being and environment had not been scientifically carried out. This review paper provides some aspects of genetically modified foods with their benefits, hazards and future prospects. [ABSTRACT FROM AUTHOR]

In this study, jute stick (JS), the underexplored by‐product of jute (Corchorus olitorius) cultivation system, has been used as a novel low‐cost adsorbent to remove methylene blue (MB), a cationic dye, from an aqueous medium. Box–Behnken design matrix and response surface methodology (RSM) have been used to evaluate the effect of four important process factors namely, solution pH (3–11), adsorbent dose (0.5–5 g L−1), initial dye concentration (50–200 mg L−1), and time (60–180 min). JS was characterized by physico‐chemical parameters, pHzpc (zero‐point charge), FTIR for the functional groups and SEM–EDX for surface morphology. The direct and interaction effects of adsorption parameters were studied. The optimum values of pH, dose, initial concentration, and time for maximum % dye removal were 10.27, 5 (g L−1), 200 (mg L−1), and 66.06 min. Regeneration and recycling studies were also carried out. The present study indicated that JS, a bio‐waste of jute cultivation system, can be effectively utilized as an adsorbent to treat MB contaminated aqueous medium/ wastewater before environmental disposal. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019 [ABSTRACT FROM AUTHOR]

Background: False detection of pesticides in agricultural produce may raise serious questions regarding both consumer safety and trade. High levels of delta-hexachlorocyclohexane (δ-HCH; 11.7-22.3 mg/kg) were detected in some tobacco samples in a retention time-based GC analysis. Hence, the selection of an appropriate analytical method is an uncompromisable necessity. Objectives: This research work aimed to elucidate false detection of pesticides along with identification of coeluting tobacco matrix compounds to understand the dynamics of false detection with an increase in the number of analyzed pesticides and to screen suitable analytical methods. Methods: Initially, retention time-based GC analysis was performed for monitoring of 10 pesticide residues in tobacco leaf matrix, followed by GC-MS/selected-ion monitoring (SIM) analysis. Then, the total number of pesticides to be analyzed was increased to 47, and residue analysis was performed by involving GC-MS/SIM and multidimensional (MD) GC-MS. Results: A false-positive detection of δ-HCH due to a coeluting tobacco aroma compound, neophytadiene, during residue analysis of 10 pesticides in tobacco (Nicotiana tabacum L.) leaf was observed. This problem was resolved by employing the unique quantifier and qualifier ions in SIM mode. However, with 47 pesticides, neophytadiene completely masked the signal of δ-HCH, which resulted in an impure spectrum of δ-HCH (<30% similarity match) even after application of selective quantifier and qualifier ions. Finally, MDGC-MS analysis could resolve it by chromatographic separation of the said analyte from the coeluting matrix compound. Conclusions: The findings of this work offer the potential to minimize false reporting of target pesticides to comply with consumer safety and trade standards. Highlights: The study identifies various tobacco matrix compounds coeluting with pesticides during multiresidue analysis. Neophytadiene, a tobacco aroma compound, resulted in false-positive detection of δ-HCH. The MDGC-MS could be effectively used as a confirmatory analysis tool for reliable detection of pesticide residue in tobacco leaf matrix. [ABSTRACT FROM AUTHOR]

Abstract: The research was carried out to ascertain the effect of three chloroacetanilide herbicides, alachlor, butachlor and pretilachlor on soil microbial biomass growth and activity. Laboratory experiments were performed in a silty clay loam soil to relate changes of soil enzymatic activity to the herbicide persistence under laboratory condition up to 42 days at three application rates. The results showed that all the three herbicides caused enhancement of dehydrogenase activity. Higher concentrations of herbicide resulted in enhancement of the enzymatic activity. In addition, a similar trend was observed in β-glucosidase and acid phosphatase activity, although urease activity decreased upon incubation for 42 days as compared with initial soil incubation values. Based on the extent of impact for dehydrogenase activity in soil, the order was pretilachlor>alachlor>butachlor; whereas in case of urease activity, the order changed to pretilachlor>butachlor>alachlor. The soil half-lives of alachlor, butachlor and pretilachlor respectively, were 9.3, 12.7 and 7.3 days, which could be accounted for in terms of their respective chemical structures, as well as variable adsorption, degradation, differential effects of the agents on soil microbes. Soil management practices and the differing physicochemical properties of the herbicides may contribute to their rates of decay in soil. [Copyright &y& Elsevier]

For the first time, jute activated carbon (JAC), a byproduct of the jute industry, was characterised and evaluated for its cleanup efficiency in a mixture of 181 multiclass pesticide residue testing using gas chromatography tandem mass spectrometry (GC-MS/MS). Four commercially-important food matrices including okra, spinach, pomegranate and tea were chosen. Various physico-chemical techniques were used to characterise the material. The cleanup method involved dispersive solid phase extraction (dSPE) using a combination of JAC (5 mg) with 25 mg of primary secondary amine per mL of the sample extract (in ethyl acetate). The findings demonstrated a lower matrix effect and higher signal-to-noise ratio were recorded for JAC. Overall, the method offered satisfactory recoveries for most of the pesticides in all the tested matrices. The cleanup effectiveness of JAC showed superiority over the commercially available, non-renewable dSPE sorbent viz. graphitised carbon black (GCB). With a production cost of only US Dollar ~10/kg, JAC is a low-cost alternative to commercial GCB (cost = US Dollar 11–12/g). The study valorises the potential of JAC and anticipates its large-scale application in food testing laboratories. • Jute activated carbon (JAC) as a cleanup agent in pesticide residue analysis. • JAC provided efficient cleanup in okra, spinach, pomegranate and tea. • The GC-MS/MS method performance was satisfactory for multiclass pesticides. • JAC is a cost-effective alternative of commercially available carbon sorbents. [ABSTRACT FROM AUTHOR]