Column study using modified banana pseudo stem as adsorbent for removal of Pb (II).

Eco-friendly adsorbents such as banana pseudo stem play a fundamental role in the removal of heavy metal elements from the wastewater. Key water resources and chemical industries have been encountering difficulties in removing heavy metal elements using existing conventional methods. The lead-removal process is currently a challenging task for environmental scientists and engineers in terms of cost, effluent disposal, and safety concerns. Hence, this work demonstrates the adsorption of Pb (II) onto modified banana pseudo stem (MBPS) powder as a potential adsorbent to treat different effluents. A characterization of modified banana pseudo-stem powder was performed using scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy which confirms the material. Experiments carried out using a column process for the removal of lead (II) from an aqueous solution at a fixed concentration of 50 ppm, pH 6 and contact time 120 min. The BET surface area of MBPS was found to be 7.27 m2/g. The results showed that the column studies explain better performance for the removal of Pb (II) and the maximum removal was found to be 49% at lower flow rate (5 mL/min) of fixed initial concentration of 50 ppm.

Genome-wide identification and expression analysis of the mating-responsive genes in the male accessory glands of Spodoptera litura (Lepidoptera: Noctuidae).

BACKGROUND: Mating elicits significant changes in gene expression and leads to subsequent physiological and behavioural modifications in insects. The reproductive success of both sexes is contributed immensely by the male accessory gland (MAG) proteins that are transferred along with sperms to the female reproductive tract during mating where they facilitate several processes that modify the post-mating behaviour. The mating-responsive genes in the MAGs have been identified and reported in many insects but have not been well-characterized in the important agricultural pest Spodoptera litura. Here, we present RNA sequencing analysis to identify mating-responsive genes from the accessory glands of virgin males and males interrupted during mating. RESULTS: Overall, 91,744 unigenes were generated after clustering the assembled transcript sequences of both samples, while the total number of transcripts annotated was 48,708 based on sequence homology against the non-redundant (NR) database. Comparative transcriptomics analysis revealed 16,969 genes that were differentially expressed between the two groups, including 9814 up-regulated and 7155 down-regulated genes. Among the top 80 genes that were selected for heat map analysis, several prominent genes including odorant binding protein, cytochrome P450, heat shock proteins, juvenile hormone binding protein, carboxypeptidases and serine protease were differentially expressed. CONCLUSIONS: The identified genes are known or predicted to promote several processes that modify the female post-mating behaviour. Future studies with the individual MAG protein or in combination will be required to recognize the precise mechanisms by which these proteins alter female physiology and reproductive behaviour. Thus, our study provides essential data to address fundamental questions about reproduction within and among insects and also paves way for further exploration of the functions of these proteins in female insects.

Critical analysis of application of generalized distance function for optimization of important variables for esterase synthesis by Saccharomyces cerevisiae.

The generalized distance function approach is employed to obtain a suitable near optimal conditions of variables. The optimal values of variables (medium constituents, microbiological parameters, and process parameters) have been evaluated separately using single responses (either specific esterase activity or cell mass) as per central-composite-design and multi-responses following generalized distance function approach. The optimal conditions (medium composition (gl(-1)): dextrose, 13.43; peptone, 7.285; yeast extract, 2.55; and malt extract, 1.695; microbiological parameters: slant age, 39.9h; inoculum age, 9.6 h; and number of cells, 1.49 x 10(8) numbers ml(-1); process conditions: temperature, 29.9 degrees C; and pH, 6.2) obtained by generalized distance approach can be considered as a 'near optimal' solution of interactive multi-response systems of intracellular esterase synthesis by Saccharomyces cerevisiae.

Production and applications of esterases.

Esterase plays a major role in the degradation of natural materials and industrial pollutants, viz., cereal wastes, plastics, and other toxic chemicals. It is useful in the synthesis of optically pure compounds, perfumes, and antioxidants. The potential applications of esterase with reference to agriculture, food, and pharmaceutical industries, are discussed in this review. Promising applications in this avenue can be supported by appropriate production strategies.