Characterization, genetic regulation and production of cyanobacterial exopolysaccharides and its applicability for heavy metal removal.

Cyanobacteria are uniquely suited for the development of sustainable bioproduction platforms but are currently underutilized due to lack of genetic tools. Exopolysaccharide (EPS) is of significant biotechnological importance due to their technological application in various industries. It has been found that most of the research works are focused on isolation and characterization of new exopolysaccharides from microbial sources. The exopolysaccharides from cyanobacteria have been poorly explored despite their original structural features associated with specific biological and physicochemical properties. However, it could increase in a near future through the use of inexpensive cyanobacterial platform as well as available information on the structural data and specific properties of these biopolymers. This review covers genetic regulation for production of exopolysaccharide, analytical strategies for their characterization, evaluation of structure property relationship and design of extraction protocol from cyanobacterial biomass. In addition applications of exopolysaccharide for removal of heavy metal from wastewater are critically reviewed.

Performance improvement of microbial fuel cell (MFC) using suitable electrode and Bioengineered organisms: A review.

There is an urgent need to find an environment friendly and sustainable technology for alternative energy due to rapid depletion of fossil fuel and industrialization. Microbial Fuel Cells (MFCs) have operational and functional advantages over the current technologies for energy generation from organic matter as it directly converts electricity from substrate at ambient temperature. However, MFCs are still unsuitable for high energy demands due to practical limitations. The overall performance of an MFC depends on microorganism, appropriate electrode materials, suitable MFC designs, and optimizing process parameters which would accelerate commercialization of this technology in near future. In this review, we put forth the recent developments on microorganism and electrode material that are critical for the generation of bioelectricity generation. This would give a comprehensive insight into the characteristics, options, modifications, and evaluations of these parameters and their effects on process development of MFCs.

Optimization of physical and morphological regime for improved cellulase free xylanase production by fed batch fermentation using Aspergillus niger (KP874102.1) and its application in bio-bleaching.

The physiological and morphological changes were extensively studied during fed batch fermentation using newly isolated Aspergillus niger (KP874102.1). Significantly higher xylanase production was possible through optimization of environmental stresses by fed batch process. The fed batch fermentation was carried out for improved xylanase production (2524 U) where initial xylan was kept 1.5 g/L in the production medium. However, 3 g/L of xylan with 50 mM K2HPO4 having pH-7 was consecutively fed at 72 and 120 h of fermentation. K2HPO4 showed significant role both the morphology of the microorganism and produces enzymes in fed batch fermentation. During feeding phase, the pH was found in the range of 6.5 to 7 which was used as marker for the fed batch process. The crude enzyme was used for the bio-bleaching of banana pulp.

Rapid development of xylanase assay conditions using Taguchi methodology.

The present investigation is mainly concerned with the rapid development of extracellular xylanase assay conditions by using Taguchi methodology. The extracellular xylanase was produced from Aspergillus niger (KP874102.1), a new strain isolated from a soil sample of the Baramura forest, Tripura West, India. Four physical parameters including temperature, pH, buffer concentration and incubation time were considered as key factors for xylanase activity and were optimized using Taguchi robust design methodology for enhanced xylanase activity. The main effect, interaction effects and optimal levels of the process factors were determined using signal-to-noise (S/N) ratio. The Taguchi method recommends the use of S/N ratio to measure quality characteristics. Based on analysis of the S/N ratio, optimal levels of the process factors were determined. Analysis of variance (ANOVA) was performed to evaluate statistically significant process factors. ANOVA results showed that temperature contributed the maximum impact (62.58%) on xylanase activity, followed by pH (22.69%), buffer concentration (9.55%) and incubation time (5.16%). Predicted results showed that enhanced xylanase activity (81.47%) can be achieved with pH 2, temperature 50°C, buffer concentration 50 Mm and incubation time 10 min.