A review on physico-chemical delignification as a pretreatment of lignocellulosic biomass for enhanced bioconversion.

Effective pretreatment of lignocellulosic biomass (LCB) is one of the most important steps in biorefinery, ensuring the quality and commercial viability of the overall bioprocess. Lignin recalcitrance in LCB is a major bottleneck in biological conversion as the polymerization of lignin with hemicellulose hinders enzyme accessibility and further bioconversion to fuels and chemicals. Therefore, there is a need to delignify LCB to ease further bioprocessing.

Molecular Characterization, Regioselective and Synergistic Action of First Recombinant Type III α-L-arabinofuranosidase of Family 43 Glycoside Hydrolase (PsGH43_12) from Pseudopedobacter saltans.

α-L-Arabinofuranosidase (PsGH43_12) of family 43 glycoside hydrolase and subfamily 12 from Pseudopedobacter saltans was cloned, over-expressed and biochemically characterized. PsGH43_12 displayed molecular mass, ~ 65 kDa. It exhibited activity in pH (5-9) and temperature range (35-55 °C) with maxima at pH 6.

Assessment of combination of pretreatment of stalk and production of chimeric enzyme (β-glucosidase and endo β-1,4 glucanase, GH1-L1-GH5-F194A) and cellobiohydrolase (CBH5A) for saccharification to produce bioethanol.

Optimization of pretreatment and saccharification of stalk (Sds) was carried out. The chimeric enzyme (GH1-L1-GH5-F194A) having β-glucosidase (GH1) and endo β-1,4 glucanase activity (GH5-F194A) and cellobiohydrolase (CBH5A) from were used for saccharification. Chimeric enzyme will save production cost of two enzymes, individually.

Enzymatic hydrolysis of hemicellulose from pretreated Finger millet (Eleusine coracana) straw by recombinant endo-1,4-β-xylanase and exo-1,4-β-xylosidase.

This study focuses on enzymatic saccharification of hemicellulose part of the pretreated Finger millet straw (FMS) for production of xylose. The variation in the carbohydrate composition of FMS was analysed when subjected to different pretreatments. The recombinant endo-1,4-β-xylanase (CtXyn11A) was most active on the FMS pretreated with 1% (w/v) NaOH combined with oven heating at 120 °C for 20 min, resulting in a total reducing sugar yield (TRS) of 32 mg/g pretreated biomass.

Development of bi-functional chimeric enzyme (CtGH1-L1-CtGH5-F194A) from endoglucanase (CtGH5) mutant F194A and β-1,4-glucosidase (CtGH1) from Clostridium thermocellum with enhanced activity and structural integrity.

Site-directed mutagenesis of β-1,4-endoglucanase from family 5 glycoside hydrolase (CtGH5) from Clostridium thermocellum was performed to develop a mutant CtGH5-F194A that gave 40 U/mg specific activity against carboxymethyl cellulose, resulting 2-fold higher activity than wild-type CtGH5. CtGH5-F194A was fused with a β-1,4-glucosidase, CtGH1 from Clostridium thermocellum to develop a chimeric enzyme. The chimera (CtGH1-L1-CtGH5-F194A) expressed as a soluble protein using E.