Xylanase

About: Xylanase is a research topic. Over the lifetime, 7099 publications have been published within this topic receiving 163793 citations.

Bioprocessing of agro-industrial residues for optimization of xylanase production by solid- state fermentation in flask and tray bioreactor

Abstract: Xylanases encompass a broad spectrum of industrial applications like food, animal feed, textile and biofuel. This study aimed at optimization of solid-state fermentation by Aspergillus niger CCUG33991 for maximum xylanase production using low-cost agro-industrial residues 1 in tray bioreactor. SSF 2 was performed using wheat bran, sorghum stover, corn cob and soybean meal in flasks for investigation of appropriate substrate, initial pH, media composition and minerals solution. Thereafter, the obtained results combined with results of earlier experiments were used for exploring the effects of particle size, initial moisture content and temperature in tray bioreactor. OFAT method 3 was followed to select optimum level of each parameter. Next, effect of air-drying and pelleting condition were tested on enzyme stability. Finally, the extracted enzymes were subjected to zymography. The highest xylanase activity of 2919±174 U/g-IDW 4 at 48 h was achieved using wheat bran with particle size range of 0.3–0.6 mm, initial moisture level of 70%, moistened by distilled water containing 1% (v/v) glycerol and 1% (w/v) of (NH4)2SO4, and controlled bed temperature in the range of 28–35 °C with surface aeration. As a result, a 2.5-fold higher and 24 h faster xylanase production in trays than in flasks was attained. The enzyme also showed a great deal of stability to air-drying and pelleting condition. Zymogram analysis confirmed multiple isoforms of xylanase. SSF in tray bioreactor is a potential method for xylanase production. Wheat bran as low-cost, time-saving and xylan-containing hemicellulosic agro-waste is preferable to use as the carbon and energy sources for maximum production of xylanase.

In vivo enzymatic digestion, in vitro xylanase digestion, metabolic analogues, surfactants and polyethylene glycol ameliorate laccase production from Ganoderma sp. kk-02.

Abstract: Aims: The effect of in vivo enzymatic digestion (IVED), in vitro xylanase digestion (IVXD), metabolic analogues, surfactants and polyethylene glycol (PEG) on laccase production from Ganoderma sp kk-02 was studied Methods and Results: An acidic laccase producing Ganoderma sp kk-02 produced 160 U ml -1 and 3650 U g -1 of laccase, when grown under submerged (SmF) and solid state (SSF) fermentation conditions, respectively Modification of the substrate (wheat bran) molecular architecture by IVED and IVXD increased subsequent laccase production from Ganoderma sp kk-02 by 131-fold (210 U ml -1 ) (SmF); 221-fold (8100 U g -1 ) (SSF) and 110-fold (180 U ml -1 ) (SmF); 178-fold (6500 U g -1 ) (SSF) when compared with untreated wheat bran Further enhancement in laccase yield under SmF and SSF was obtained when IVED treated wheat bran was used in conjunction with amino acids [DL-tryptophan, 266-fold (560 U ml -1 ) SmF; 286-fold (23240 U g -1 ) SSF], vitamins [biotin, 171-fold (360 U ml -1 ) SmF; 306-fold (24830 U g -1 ) SSF], surfactants [Tween-40, 185-fold (390 U ml -1 ) SmF; 225-fold (18280 U g -1 ) SSF], and PEG [PEG 6000, 193-fold (400 U ml -1 ) SmF; 158-fold (12840 U g -1 ) SSF] Conclusions: The IVED of substrate (wheat bran) facilitated hyper laccase production in presence of additives from Ganoderma sp kk-02 Significance and Impact of the Study: The study highlights a new methodology viz IVED for concomitant and economic production of diverse enzymes using the same substrate The hyper laccase levels obtained could improve the economic competitiveness of environmentally benign processes applied in varied industries The work also provides an insight into the regulation of complex metabolic pathways governing the expression of extra cellular proteins from white-rot fungi