Optimized Production of Xylanase by Penicillium purpurogenum and Ultrasound Impact on Enzyme Kinetics for the Production of Monomeric Sugars From Pretreated Corn Cobs

Abstract

Corn cob is an abundant organic source with significant potential in sustainable energy development. For the effective conversion of the feedstocks to valued commodities, effective biocatalysts are highly desired. The present study aims at optimizing the critical parameters required for xylanase production by Penicillium purpurogenum isolated from rotten wood sample using the Taguchi orthogonal array layout of L25 (5 ∧ 6). The optimized conditions like temperature 40 • C, pH 3, size of inoculum 1.2 × 10 8 spores/ml, moisture 70%, peptone 0.8%, and 5 days of incubation resulted in 1,097 ± 6.76 U/gram dry substrate (gds) xylanase which was 65.72% more when compared to un-optimized production of xylanase. The xylanase thus produced, effectively carried out pretreated corn cob saccharification and the reaction was further improved with ultrasound assistance which has increased the saccharification yield to 12.02% along with significant reduction in reaction time. The saccharification efficiency of pretreated corn cob was found to be 80.29% more compared to the raw corn cob, reflecting its recalcitrance to digestion. Indeed, xylan being the second most abundant polymer in lignocellulosic biomass, considerable attention is being paid for its effective conversion to valued products.

Use of Wheat Straw for Value-Added Product Xylanase by Penicillium chrysogenum Strain A3 DSM105774

“…Mostly, the optimal incubation temperature prompting the maximal xylanase production by the mesophilic fungi was reported to localize at 25-30 • C. The maximal xylanase production by P. citrinum xym2 [56], P. chrysogenum F-15 strain [54], and P. glabrum [57] was realized at 30, 20, and 25 • C, respectively. On the contrary, the maximum xylanase production by P. purpurogenum was accomplished at 40 • C [35]. At most, applying mild incubation temperatures (25-30 • C) in enzyme bioprocessing, would not only prevent the protein misfolding and its undesirable consequences [58] but also contribute greatly to energy saving, accompanying by lower bioprocesses' expenditures.…”

“…Over the few last decades, numerous fungal strains were tried for the production of live xylanases using lignocelluloses agro-industrial waste byproducts such as sorghum straw by Thermomyces lanuginosus (D 2 W 3 ) [ 22 ], rice husk by T. lanuginosus strain A3-1 DSM 105773 [ 23 ], rice bran by Humicola lanuginosa [ 24 ], rice straw by Aspergillus fumigatus NITDGPKA3 [ 25 ], wheat bran by P. chrysogenum PCL501 [ 26 ], wheat straw by Paecilomyces thermophia [ 27 ] and Melanocarpus albomyces IITD3A [ 28 ], and maize straw by Trichoderma viride [ 29 ]. Several Penicillum spp (e.g., Penicillium oxalicum ZH-30 [ 30 ], P. oxalicum T3.3 [ 31 ], P. pinophilum NTG1 II/6 [ 32 ], P. decumbens [ 33 ], P. janthinelum CRC 87M-115 [ 34 ], P. purpurogenum [ 35 ], P. echiulatum [ 36 ], P. expansum [ 37 ], P. chrysogenum PCL501 [ 26 ], and P. canescens (10-10c) [ 38 ] have been intensely studied for their capability to manufacture live xylanases upon their cultivation on wheat bran, wheat straw, rice straw, corncob, oat husk, and barely straw. However, the valorization of WS to a value-added product xylanase by P. chrysogenum (recently designated as P. rubens ) has not been attempted yet.…”

Citrus Segment Degradation Potential, Enzyme Safety Evaluation, and Whole Genome Sequence of Aspergillus aculeatus Strain ZC-1005

“…Filamentous fungi are the main microbial strains for cellulase production, including Trichoderma , Aspergillus , and Penicillium ( Zhang et al, 2003 ). These studies mainly focused on the production process of xylanase (such as culture conditions and enzyme inducers) ( Ramanjaneyulu and Rajasekhar Reddy, 2016 ; Sunkar et al, 2020 ), purification and identification of xylanase, and enzymatic characteristics ( Gao et al, 2017 ; Sherien et al, 2020 ; Torkashvand et al, 2020 ; Cao et al, 2021 ). Aspergillus niger ( Diogo et al, 2018 ), Trichoderma ( Schmoll, 2018 ), Streptomyces cirratus ( Zhang, 2004 ), Streptomyces lividans ( Dupont et al, 1996 ), Streptomyces olivochromogenes ( Gregory et al, 1987 ), and rumen microorganisms ( Yousuf et al, 2010 ) are the main microorganisms that degrade hemicellulose.…”

Bioprospecting Fungal Glycosyl Hydrolases: Multi-locus Phylogenetic Analysis and Enzyme Activity Profiling for Enhanced Biomass Valorization

“…Enzymatic sacchari cation of lignocellulosic biomass is a feasible alternative to physico-chemical treatment but its usage is limited owing to the high cost of enzymes. On the other hand, a vast array of indigenous microorganisms can be exploited for production of desirable glycosyl hydrolases via submerged (SmF) or solid-state fermentation (SSF) by substituting puri ed xylan with lignocellulosic biomass as substrate for providing the necessary nutrients for the microbial growth and the induction of the enzymatic production (Sunkar et al 2020). SmF system accounts nearly for 90% of total xylanase produced worldwide (Polizeli et al 2005) and is considered more exible for allowing large-scale fermentations (Taddia et al 2020).…”

“…Holocelluloses (cellulose and all of the hemicellulose) forms major fraction of lignocelluloses along with lignin which can be ideally hydrolyzed to monosaccharides for effective conversion to various value-added products. Traditional thermochemical methods utilized for degradation of lignocelluloses typically generate toxic by-products, therefore emphasis is laid on enzymatic sacchari cation considering the cost and yield in the biore neries (Varghese et al 2017;Sunkar et al 2020). Lignocellulosic biomass is naturally degraded by diverse glycosyl hydrolases (GHs) producing microorganisms that can be utilized for several industrial as well as biotechnological applications.…”