Biodegradation of 4-chlorophenol in batch and continuous packed bed reactor by isolated Bacillus subtilis.

In present work, biodegradation of 4-Chlorophenol (4-CP) has been successfully achieved using bacteria i.e. Bacillus subtilis (MF447841.1), which was isolated from the wastewater of a nearby drain of Hyundai Motor Company service centre, Agartala, Tripura (India). Geonomic identification was carried out by 16 S rDNA technique and phylogenetic processes. Both, batch and column mode of experiments were performed to optimize various parameters (initial concentration, contact time, dosages etc.) involved in the significant biodegradation of 4-CP. Based on R2 value (0.9789), the Levenspiel's model was found to be best fit than others. The kinetic parameters; specific growth rate (µ), yield of cell mass (YX/S), and saturation constant (KS), were obtained as 0.6383 (h-1), 0.35 (g/g), and 0.006884 (g/L), respectively. The isolated strain has shown the ability of degrading 4-CP up to 1000 mg/L initial concentration within 40 h. Bacterial strain was immobilized via developing calcium alginate beads along by optimizing weight proportion of calcium chloride and sodium alginate and size of the bead for further experiments. Various process parameters i.e. initial feed concentration, bed height, rate of flow of were optimized during packed bed reactor (PBR) study. Maximum biodegradation efficiency of 4-CP was observed as 45.39% at initial concentration of 500 mg/L within 105 min, using 2 mm size of immobilized beads which were formed using 3.5% w/v of both calcium chloride and sodium alginate within. Thus, Bacillus subtilis (MF447841.1) could be used for biological remediation of 4-CP pollutant present in wastewater. Moreover, because of affordable and eco-friendly nature of water treatment, relatively it has the better scope of commercialization.

Estimation of health risks due to copper-based nanoagrochemicals.

This study estimated health risks due to two types of copper-based nanoagrochemicals (Cu (OH)2 and CuO nanoparticles (NPs)), during inadvertent ingestion of soil and consumption of leafy vegetables for a hypothetical exposure scenario. The dissolution of copper-based nanoagrochemicals in human digestive system was considered for estimating realistic doses. No risk was found during soil ingestion (hazard quotient (HQ) <1). HQ (no dissolution of Cu (OH) 2 nanopesticides) (HQ= 0.015) comes out to be 2 times higher than that of HQ (100% dissolution of Cu (OH)2 nanopesticides into copper ions) (HQ= 0.007). In case of risk from consumption of leafy vegetables, the following order of risk was found (high to low HQ value): Cu (OH)2 (HQ= 1925) >CuO NPs (1402). Combined exposure of Cu (OH)2 nanopesticide through soil ingestion as well as consumption of contaminated edible leafy vegetables resulted in health risks. The calculated maximum allowable applicable concentration values of Cu (OH)2 and CuO NPs without posing risk to human and plant toxicity were found to be 1.14 and 0.45 mg/L, respectively. These findings can be used now for deciding safe use of copper-based nanoagrochemicals.

Lipases: Sources, Production, Purification, and Applications.

Background and Sources: Lipase enzyme is a naturally occurring enzyme found in the stomach and pancreatic juice. Its function is to digest fats and lipids, helping to maintain correct gallbladder function. Lipase is the one such widely used and versatile enzyme. These enzymes are obtained from animals, plants and as well as from several microorganisms and are sufficiently stable. These are considered as nature's catalysts, but commercially, only microbial lipases are being used significantly. Applications: They found enormous application in the industries of fat and oil processing, oleochemical industry, food industry, detergents, pulp and paper industry, detergents, environment management, tea processing, biosensors and cosmetics and perfumery. Various recent patents related to lipases have been revised in this review. Conclusion: Lipases are very peculiar as they have the ability to hydrolyse fats into fatty acids and glycerols at the water-lipid interface and can reverse the reaction in non-aqueous media. This natural ability makes it the most widely used enzyme in various industrial applications. This article deals with the immense versatility of lipase enzymes along with the recent advancements done in the various fields related to their purification and mass production in industries.

Mode of Action, Properties, Production, and Application of Laccase: A Review.

Background and Source: Laccase belongs to the blue multi-copper oxidases, which are widely distributed in fungi and higher plants. It is present in Ascomycetes, Deuteromycetes, and Basidiomycetes and found abundantly in white-rot fungi. Applications: Laccase enzymes because of their potential have acquired more importance and application in the area of textile, pulp and paper, and food industry. Recently, it is being used in developing biosensors for detection and removal of toxic pollutants, designing of biofuel cells and medical diagnostics tool. Laccase is also being used as a bioremediation agent as they have been found potent enough in cleaning up herbicides pesticides and certain explosives in soil. Because of having the ability to oxidize phenolic, non-phenolic lignin-related compounds and highly fractious environmental pollutants, laccases have drawn the attention of researchers in the last few decades. Commercially, laccases have been used to determine the difference between codeine and morphine, produce ethanol and are also being employed in de-lignify woody tissues. We have revised patents related to applicability of laccases. We have revised all the patents related to its wide applicability. Conclusion: For fulfillment of these wide applications, one of the major concerns is to develop a system for efficient production of these enzymes at a broad scale. Research in the field of laccases has been accelerated because of its wide diversity, utility, and enzymology. This paper deals with recent trends in implementation of the laccases in all practical possibilities with the help of optimizing various parameters and techniques which are responsible for mass production of the enzyme in industries.