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[Display omitted] • Hydrothermal pretreatment is a sustainable approach for the recovery of XOS. • XOS and GOS of 23.7 and 18.3% respectively was obtained under best conditions. • Conduritol B epoxide served as inhibitor for controlled hydrolysis to get cellobiose. • After controlled hydrolysis 174 mg of cellobiose was obtained per gram of biomass. Globally, the demands for sustainably sourced functional foods like prebiotic oligosaccharides have been constantly increasing. This study assessed the potential of pineapple leaves (PL) as lignocellulosic feedstock for sustainable production of cellulose and hemicellulose-derived oligosaccharides through its hydrothermal pretreatment (HT) followed by controlled enzymatic hydrolysis. PL was subjected to HT at 160, 175, and 190 °C for 20, 30, 60, and 90 min without any catalyst for xylooligosaccharide (XOS) production, whereas, the resulting solid content after HT was subjected to controlled enzymatic hydrolysis by commercial cellulase using conduritol B epoxide (0.5–5 mM) for glucooligosaccharides (GOS) production. HT at 160 °C for 60 min resulted in maximum yield of XOS and GOS at 23.7 and 18.3 %, respectively, in the liquid phase. Controlled enzymatic hydrolysis of HT treated (160 °C) PL solids for 20 and 30 min yielded ∼ 174 mg cellobiose/g dry biomass within 24 h, indicating overall high oligosaccharide production. [ABSTRACT FROM AUTHOR]

Bio-ethanol production from pretreated biomass in a single vessel was investigated in which cellulase production via SSF by Penicillium janthinellum EMS-UV-8, hydrolysis of biomass and ethanol fermentation was carried out sequentially. In this study, feasibility of using whole fermented matter with enzyme, fungal mycelia, spores and residual substrate, for the saccharification of pretreated wheat straw or avicel and its further fermentation to ethanol was investigated. Whole fermented matter produced during cellulase production via solid-state fermentation and extracted cellulase was compared for hydrolysis efficiency toward cellulosic biomass. Ethanol fermentation by Kluveromyces marxianus MTCC 4136 was investigated for both the above cases and no significant difference was observed. We could obtain similar titers of ethanol by both methods. Employing the whole fermented matter offered advantages over using extracted enzyme by reducing enzyme extraction step and thereby reducing economic constraint. [ABSTRACT FROM AUTHOR]

Present study was focused on cellulase production from an indigenously isolated filamentous fungal strain, identified as Penicillium oxalicum . Initially, cellulase production under submerged fermentation in shake flasks resulted in cellulase activity of 0.7 FPU/mL. Optimization of process parameters enhanced cellulase production by 1.7-fold and resulted in maximum cellulase activity of 1.2 FPU/mL in 8 days. Cellulase production was successfully scaled-up to 7 L fermenter under controlled conditions and incubation time was reduced from 8 days to 4 days for achieving similar cellulase titer. Optimum pH and temperature for activity of the crude enzyme were pH 5 and 50 °C, respectively. At 50 °C the produced cellulase retained approximately 50% and 26% of its activity at 48 h and 72 h, respectively. Hydrolytic efficiency of P. oxalicum was comparable to commercial cellulase preparations which indicate its great potential for application in the lignocellulose hydrolysis. [ABSTRACT FROM AUTHOR]

This study concerns in-house development of cellulases from a mutant Penicillium janthinellum EMS-UV-8 and its application in separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes for bioethanol production from pre-treated wheat straw. In a 5 L fermentor, the above strain could produce cellulases having activity of 3.1 FPU/mL and a specific activity of 0.83 FPU/mg of protein. In-house developed cellulase worked more efficiently in case of SSF as ethanol concentration of 21.6 g/L and yield of 54.4% were obtained which were higher in comparison to SHF (ethanol concentration 12 g/L and 30.2% yield). This enzyme preparation when compared with commercial cellulase for hydrolysis of pre-treated wheat straw was found competitive. This study demonstrates that P. janthinellum EMS-UV-8 is a potential fungus for future large-scale production of cellulases. [ABSTRACT FROM AUTHOR]

Co-culture of fungal strains Penicillium janthinellum EMS-UV-8 (E), Penicillium funiculosum strain P (P) and Aspergillus sp. strain G (G) and blending of their crude cellulase were evaluated for improvements in cellulase activities as well as for enhanced hydrolysis of dilute acid pretreated wheat straw (PWS). The blending of crude enzymes of P and E enhanced the hydrolysis of PWS more effectively due to synergism in cellulolytic enzyme activities. Here, three types of blends were made on the basis of equal FPUs, equal protein content or fixed volume containing different proportions of individual enzymes, the former blend hydrolyzed 42.6% of PWS due to the 98%,62%, 64% and 34% synergistic enhancement in endo-glucanase, cellulase (FPU), β-glucosidase and xylanase activities, respectively. Hydrolysis at 10% solid loading of PWS in roller bottle reactor with this blend further enhanced hydrolysis yield to 74% within 24 h, which was much better than the corresponding hydrolysis yields of individual (38.1% by E and 61.5% by P) or the commercial enzyme (62.3%). This study proved that synergistic blends of cellulases from two Penicillium spp. are cost-effective tools for efficient wheat straw hydrolysis for on-site biofuel production. [ABSTRACT FROM AUTHOR]