Fungi are considered good producers of industrially valuable enzymes with higher enzymatic activities. Among these cellulases are group of extracellular enzymes commonly employed in many industries for the hydrolysis of cellulolytic material. Aspergillus fumigatus produced exoglucanase having high enzymatic activity (83 U/gds) during the solid-state fermentation of wheat straw under optimum physical and nutritional conditions. Maximum production was obtained after 72 h of fermentation, at 55 °C temperature, pH 5.5, 80 % moisture level, and 2 mL fungal inoculum. Production was further increased by the addition of fructose (0.3 %) as additional carbon source, peptone (0.4 %) as nitrogen source, Tween-80 (0.3 %) as surfactant, and ammonium sulfate (0.2 %) in media. Exoglucanase was 2.30-folds purified by adding 40 % ammonium sulfate with volumetric activity 95.4 U/gds and specific activity 14.74 U/mg. Further, it was 5.18-folds purified by gel filtration chromatography with volumetric activity 115.2 U/gds and specific activity 33.10 U/mg. Purified exoglucanase has maximum activity at 55 °C and pH 4.8 using 1 % Avicel aqueous solution as substrate. The K(m) and V(max) were 4.34 mM and 7.29 μM/min, respectively. Calcium, magnesium, and zinc ions have positive effect on exoglucanase activity.

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The main objectives of this study were to optimize the culture conditions for the production of lignin peroxidase by Ganoderma leucidum, economic utilization of waste corn cobs as inducers substrate by pollution free fermentation technology and to optimize the solid state fermentation (SSF) process for lignin peroxidase (LiP) production. Growth medium employed for the culture of G. leucidum for the production of LiP was supplied with fermentation conditions that were optimized before selection like incubation period, inoculum size, temperature, pH, substrate to water ratio, nitrogen source, yeast extract and cane molasses. Culture was harvested on the fourth day and diluted five times with distilled water and filtrate was stored in Eppendoff tubes for enzyme assay using 310 nm wave lengths in the spectrophotometer. Lignin peroxidase production was enhanced and maximum LiP activity (2807 U/ml) was found in the growth medium after 96 h, inoculum size 3 ml, pH 4.5 and temperature 35°C with substrate to water ratio of 20 ml/5 g, yeast extract 4%, (NH 4) 2 SO 4, 2% and cane molasses 3%. Results indicate the excellent scope of corn cobs as solid state substrate for the production of lignin peroxidase by G. leucidum.

Textile dyes accounts for 22 % of total dyes utilization and are potential pollutants due to their toxicity and carcinogenicity. Brown Rot Fungi (BRF) have great potential of biodegradation of dyestuffs due to their efficient nonspecific ligninolytic enzyme system. Current study was conducted for application of indigenous Daedalea dickinsii IEBL-2, a brown rot fungi, to degrade single azo disperse dyes i.e. disperse violet-63 and disperse orange-30. Response Surface Methodology (RSM) with Box Behnken Design was employed to optimized biodegradation process. Ligninolytic enzymes involved in biodegradation were also studied and biodegradation process was monitored by High Performance Liquid Chromatography (HPLC). There was 72.14±1.1% and 68.71±1.04% biodegradation observed after screening experiments for dye-1 and dye-2. Optimization by RSM at step-1 increases biodegradation to 80.83±1.35% and 78.3±1.16% and after step-2, 88.93±1.32% and 93.32±1.54% respectively. Study of ligninolytic enzymes i.e manganese peroxidase, lignin peroxidase and laccase revealed their involvement in biodegradation process. HPLC analysis confirmed the biodegradation process and conversion of complex dyes into simple secondary amines i.e diphenylamine and 3-methyldiphenylamine. These findings would help to reduce the environmental pollution by textile effluent and also reduces the risk of certain diseases.

Endopolygalacturonases characterized until now have either low working temperatures, working pH in acidic range, high Michaelis–Menten constant (Km), or a high production cost. These characteristics are a hurdle in the industrial applications of these endopolygalacturonases. The purpose of this work was to characterize a novel endopolygalacturonase produced by Bacillus licheniformis IEB-8. Phylogenetic analysis of Bacillus licheniformis IEB-8 showed that the isolate was unique. Citrus peels were used as the only nutrient source for the growth of Bacillus licheniformis IEB-8, allowing a cheap production of endopolygalacturonase. All the synthetic carbon sources showed a negative impact on the production of endopolygalacturonase, while ammonium sulfate enhanced its production. Among different metal ions, Zn+2 showed a negative effect while Mg+2 and Ca+2 did not have any significant effect on the endopolygalacturonase activity. A Lineweaver-Burk plot was prepared for the characterization of the kinetic parameters including Km and Vmax, which were 0.45 mg/mL and 285.7 µM/min, respectively. A comprehensive comparison of the endopolygalacturonase from this study with the available literature indicated that it is better than the reported and commercially available endopolygalacturonases in having the optimum working temperature of 55 °C, a low Km of 0.57 mg/mL, and pH of 7 to 8, which indicated its novelty.