Spinning Higher Dimensional Einstein-Yang-Mills black holes

We construct a Kerr-Newman-like spacetimes starting from higher dimensional (HD) Einstein-Yang-Mills black holes via complex transformations suggested by Newman-Janis. The new metrics are HD generalization of Kerr-Newman spacetimes which has a geometry precisely that of Kerr-Newman in 4D corresponding to Yang-Mills (YM) gauge charge, but the sign of charge term gets flipped in the HD spacetimes. It is interesting to note that gravitational contribution of YM gauge charge, in HD, is indeed opposite (attractive rather than repulsive) that of Maxwell charge. The effect of YM gauge charge on the structure and location of static limit surface and apparent horizon is discussed. We find that static limit surfaces become less prolate with increase in dimensions and are also sensitive to YM gauge charge thereby affecting the shape of ergosphere. We also analyze some thermodynamical properties of these BHs.Comment: Accepted for publication in EPJ

Production and Characterization of Glucoamylase by Aspergillus niger

Background and Objective: Glucoamylase is a potent starch degrading enzyme whose cheap production has been an area of research. Its production by Aspergillus niger in solid-state fermentation was studied using dried garden pea peel as a substrate, which enormously reduced the production cost. The current study intended to produce glucoamylase by a cost-effective strategy and exhaustively characterize the enzyme.Material and Methods: Garden pea peel was used as a substrate in solid state fermentation by Aspergillus niger for the production of glucoamylase under process parameters. Response surface methodology, a statistical tool for optimization, was applied to setup the experimental design for glucoamylase production. Characterization studies of the enzyme were carried out with temperature, pH, metal salts and elemental composition analysis.Results and Conclusion: The process parameters were temperature, amount of substrate and time of fermentation. Glucoamylase production was highest in the pH range of 5.4-6.2, was stable at pH 3.8, and maintained its maximum activity even at 70°C for 30 min. It showed higher catalytic efficiency when incubated with metal ions Fe2+, Cu2+, Mg2+, and Pb2+. Km and Vmax for glucoamylase were 0.387 mg of soluble starch ml-1 and 35.03 U μl-1 min-1, respectively. Glycogen was also used as a substrate, which gave an increased Km by 2.585, whose KI was found to be 0.631. Energy-dispersive X-ray spectroscopy was performed for obtaining composition of the pea peel. C, N, and O were found to be 12.53%, 29.9%, and 55.27% by atomic weights, respectively. Cost- and time-effective production of glucoamylase was achieved by utilizing dried garden pea peel (a vegetable residue) powder as the substrate for production. Its high stability ensures efficient utilization under industrial conditions. This work provides a very good platform for the enzyme immobilization studies and scale up production in future.Conflict of interest: The authors declare that there is no conflict of interest

Optimisation of fungal glucoamylase production by Response Surface Methodology and characterisation of the purified enzyme

A statistical approach was made for the production of glucoamylase by Aspergillus niger using wheat bran and green gram as fermentation medium. Box-Behnken design used to analyse the simultaneous impact of the substrate, hydration, inoculum volume, fermentation time and temperature, using a second-order polynomial. The experimental results were in good agreement with the proposed regression model with R2 = 0.9322 (p<0.05). The maximum yield (313 U/gds against the predicted value of 306 U/gds) was obtained using 12 gm substrate, 55% moisture, 1 gm sucrose and 0.05 gm tryptone. The purification and characterisation of the enzyme were also studied. Optimum thermal and pH stability was 60 °C and 5 respectively

Immobilization of fungal cellulase on chitosan beads and its optimization implementing response surface methodology

536-543The present study deals with the immobilization of cellulase produced from our isolated fungus Aspergillus niger ISSFR-019 on different matrices of which chitosan beads has been found to be the most suitable one. The optimization of the amount of cellulase, amount of beads, temperature and amount of glutaraldehyde used as a cross-linking agent for the procurement of maximum immobilization efficiency has been done on the basis of statistical approach BBD (Box-Behnken Design). Cellulase is found to be successfully immobilized on the chitosan bead surface, with 94.2% efficiency and immobilization yield is found to be 54.1% after statistical optimization. Significant enzymatic activity is recorded after 12 cycles of reuse of the beads. The kinetic study revealed that the Michael’s Menten constant (Km) is found to be 1.3 mM and 2 mM for free enzyme and immobilized enzyme respectively, the higher Km value for immobilized enzyme indicated conformational change in the enzyme that altered the accessibility of substrate towards the active site of the enzyme. The Vmax is found to be 2.7 and 4.4 U/mg-1 respectively for the immobilized and free enzyme. Fourier Transform Infrared Spectroscopy studies revealed the change in absorbance of functional groups when the enzyme is bound to chitosan beads

Utilization of Agro industrial Food Processing Wastes and Pollutants for Manufacture of Products of Industrial Value A review

Rapid industrialization as a consequence of the population explosion has led to the expansion of the agricultureand food processing sector to feed every mouth and to meet rapidly growing market demand. Extensive harvesting and processing of crops and raw agricultural harvests, and production of secondary and tertiary wastes from industrial manufacturing operations associated with agricultural and food products have impacted the environment in adverse ways, which is causing irreparable damages. To minimize the carbon load on earth, several sustainable technologies have been developed, which can save the environment as well as generate some useful and industrially important products. This review work focuses on the current scenario of these wastes, and their harmful effects on nature in general, and on the environment in particular. It also suggests that sustainable techniques can minimize these harmful impacts, and can instead manufacture some valuable products like antibiotics, enzymes, organic acid, organic chemicals, biomass, pigment, flavors, solid fuel, and bioalcohol. Thus, this is a comprehensive and extensive account of the utilization of agricultural and food processing wastes to derive valuable, useful products