An integrated paradigm for cellulosic biorefineries: utilization of lignocellulosic biomass as self-sufficient feedstocks for fuel, food precursors and saccharolytic enzyme production

2012 ◽  
Vol 5 (5) ◽  
pp. 7100 ◽  
Author(s):  
Ming W. Lau ◽  
Bryan D. Bals ◽  
Shishir P. S. Chundawat ◽  
Mingjie Jin ◽  
Christa Gunawan ◽  
...  
Keyword(s):  
Lignocellulosic Biomass ◽  
Enzyme Production

scholarly journals Ideal Feedstock and Fermentation Process Improvements for the Production of Lignocellulolytic Enzymes

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 38
Author(s):  
Attia Iram ◽  
Deniz Cekmecelioglu ◽  
Ali Demirci
Keyword(s):  
Lignocellulosic Biomass ◽  
Enzyme Production ◽  
Bacterial Species ◽  
Hydrolytic Enzyme ◽  
Value Added ◽  
Special Focus ◽  
Lignocellulolytic Enzymes ◽  
Process Improvements ◽  
Fossil Fuel Industry ◽  
Nutrient Amendment

The usage of lignocellulosic biomass in energy production for biofuels and other value-added products can extensively decrease the carbon footprint of current and future energy sectors. However, the infrastructure in the processing of lignocellulosic biomass is not well-established as compared to the fossil fuel industry. One of the bottlenecks is the production of the lignocellulolytic enzymes. These enzymes are produced by different fungal and bacterial species for degradation of the lignocellulosic biomass into its reactive fibers, which can then be converted to biofuel. The selection of an ideal feedstock for the lignocellulolytic enzyme production is one of the most studied aspects of lignocellulolytic enzyme production. Similarly, the fermentation enhancement strategies for different fermentation variables and modes are also the focuses of researchers. The implementation of fermentation enhancement strategies such as optimization of culture parameters (pH, temperature, agitation, incubation time, etc.) and the media nutrient amendment can increase the lignocellulolytic enzyme production significantly. Therefore, this review paper summarized these strategies and feedstock characteristics required for hydrolytic enzyme production with a special focus on the characteristics of an ideal feedstock to be utilized for the production of such enzymes on industrial scales.

scholarly journals Chaetomella raphigera β-glucosidase D2-BGL has intriguing structural features and a high substrate affinity that renders it an efficient cellulase supplement for lignocellulosic biomass hydrolysis

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Mu-Rong Kao ◽  
Hsion-Wen Kuo ◽  
Cheng-Chung Lee ◽  
Kuan-Ying Huang ◽  
Ting-Yen Huang ◽  
...  
Keyword(s):  
Lignocellulosic Biomass ◽  
Structure Analysis ◽  
Enzyme Production ◽  
Large Scale ◽  
Production Costs ◽  
Site Directed Mutagenesis ◽  
Biofuel Production ◽  
Substrate Affinity ◽  
High Substrate ◽  
Chaetomella Raphigera

Abstract Background To produce second-generation biofuels, enzymatic catalysis is required to convert cellulose from lignocellulosic biomass into fermentable sugars. β-Glucosidases finalize the process by hydrolyzing cellobiose into glucose, so the efficiency of cellulose hydrolysis largely depends on the quantity and quality of these enzymes used during saccharification. Accordingly, to reduce biofuel production costs, new microbial strains are needed that can produce highly efficient enzymes on a large scale. Results We heterologously expressed the fungal β-glucosidase D2-BGL from a Taiwanese indigenous fungus Chaetomella raphigera in Pichia pastoris for constitutive production by fermentation. Recombinant D2-BGL presented significantly higher substrate affinity than the commercial β-glucosidase Novozyme 188 (N188; Km = 0.2 vs 2.14 mM for p-nitrophenyl β-d-glucopyranoside and 0.96 vs 2.38 mM for cellobiose). When combined with RUT-C30 cellulases, it hydrolyzed acid-pretreated lignocellulosic biomasses more efficiently than the commercial cellulase mixture CTec3. The extent of conversion from cellulose to glucose was 83% for sugarcane bagasse and 63% for rice straws. Compared to N188, use of D2-BGL halved the time necessary to produce maximal levels of ethanol by a semi-simultaneous saccharification and fermentation process. We upscaled production of recombinant D2-BGL to 33.6 U/mL within 15 days using a 1-ton bioreactor. Crystal structure analysis revealed that D2-BGL belongs to glycoside hydrolase (GH) family 3. Removing the N-glycosylation N68 or O-glycosylation T431 residues by site-directed mutagenesis negatively affected enzyme production in P. pastoris. The F256 substrate-binding residue in D2-BGL is located in a shorter loop surrounding the active site pocket relative to that of Aspergillus β-glucosidases, and this short loop is responsible for its high substrate affinity toward cellobiose. Conclusions D2-BGL is an efficient supplement for lignocellulosic biomass saccharification, and we upscaled production of this enzyme using a 1-ton bioreactor. Enzyme production could be further improved using optimized fermentation, which could reduce biofuel production costs. Our structure analysis of D2-BGL offers new insights into GH3 β-glucosidases, which will be useful for strain improvements via a structure-based mutagenesis approach.

scholarly journals The influence of feedstock characteristics on enzyme production in Trichoderma reesei: a review on productivity, gene regulation and secretion profiles

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Vera Novy ◽  
Fredrik Nielsen ◽  
Bernhard Seiboth ◽  
Bernd Nidetzky
Keyword(s):  
Gene Regulation ◽  
Lignocellulosic Biomass ◽  
Trichoderma Reesei ◽  
Enzyme Production ◽  
Enzymatic Saccharification ◽  
Lignocellulolytic Enzymes ◽  
Lignocellulosic Substrate ◽  
Related Factors ◽  
Promising Alternative ◽  
Set Up

Abstract Biorefineries, designed for the production of lignocellulose-based chemicals and fuels, are receiving increasing attention from the public, governments, and industries. A major obstacle for biorefineries to advance to commercial scale is the high cost of the enzymes required to derive the fermentable sugars from the feedstock used. As summarized in this review, techno-economic studies suggest co-localization and integration of enzyme manufacturing with the cellulosic biorefinery as the most promising alternative to alleviate this problem. Thus, cultivation of Trichoderma reesei, the principal producer of lignocellulolytic enzymes, on the lignocellulosic biomass processed on-site can reduce the cost of enzyme manufacturing. Further, due to a complex gene regulation machinery, the fungus can adjust the gene expression of the lignocellulolytic enzymes towards the characteristics of the feedstock, increasing the hydrolytic efficiency of the produced enzyme cocktail. Despite extensive research over decades, the underlying regulatory mechanisms are not fully elucidated. One aspect that has received relatively little attention in literature is the influence the characteristics of a lignocellulosic substrate, i.e., its chemical and physical composition, has on the produced enzyme mixture. Considering that the fungus is dependent on efficient enzymatic degradation of the lignocellulose for continuous supply of carbon and energy, a relationship between feedstock characteristics and secretome composition can be expected. The aim of this review was to systematically collect, appraise, and aggregate data and integrate results from studies analyzing enzyme production by T. reesei on insoluble cellulosic model substrates and lignocellulosic biomass. The results show that there is a direct effect of the substrate’s complexity (rated by structure, composition of the lignin–carbohydrate complex, and recalcitrance in enzymatic saccharification) on enzyme titers and the composition of specific activities in the secretome. It further shows that process-related factors, such as substrate loading and cultivation set-up, are direct targets for increasing enzyme yields. The literature on transcriptome and secretome composition further supports the proposed influence of substrate-related factors on the expression of lignocellulolytic enzymes. This review provides insights into the interrelation between the characteristics of the substrate and the enzyme production by T. reesei, which may help to advance integrated enzyme manufacturing of substrate-specific enzymes cocktails at scale.

Enhanced Delignification of Lignocellulosic Biomass by Recombinant Fungus Phanerochaete chrysosporium Overexpressing Laccases and Peroxidases

2018 ◽  
Vol 28 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Nancy Coconi Linares ◽  
Francisco Fernández ◽  
Achim M. Loske ◽  
Miguel A. Gómez-Lim
Keyword(s):  
Lignocellulosic Biomass ◽  
Phanerochaete Chrysosporium ◽  
Wheat Bran ◽  
Enzyme Production ◽  
Lignin Degradation ◽  
Laccase Activity ◽  
Ligninolytic Enzymes ◽  
Lignocellulose Degradation ◽  
Total Phenolic ◽  
Recombinant Strains

Ligninolytic enzyme production and lignin degradation are typically the rate-limiting steps in the biofuel industry. To improve the efficiency of simultaneous bio-delignification and enzyme production, <i>Phanerochaete chrysosporium</i> was transformed by shock wave-induced acoustic cavitation to co-overexpress 3 peroxidases and 1 laccase and test it on the degradation of sugarcane bagasse and wheat bran. Lignin depolymerization was enhanced by up to 25% in the presence of recombinant fungi in comparison with the wild-type strain. Sugar release on lignocellulose was 2- to 6-fold higher by recombinant fungi as compared with the control. Wheat bran ostensibly stimulated the production of ligninolytic enzymes. The highest peroxidase activity from the recombinant strains was 2.6-fold higher, whereas the increase in laccase activity was 4-fold higher in comparison to the control. The improvement of lignin degradation was directly proportional to the highest peroxidase and laccase activity. Because various phenolic compounds released during lignocellulose degradation have proven to be toxic to cells and to inhibit enzyme activity, a significant reduction (over 40%) of the total phenolic content in the samples treated with recombinant strains was observed. To our knowledge, this is the first report that engineering <i>P. chrysosporium</i> enhances<i></i> biodegradation of lignocellulosic biomass.

scholarly journals Evaluation of the capacity of laccase secretion of four novel isolated white-rot fungal strains in submerged fermentation with lignocellulosic biomass

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 6706-6722
Author(s):  
Qi An ◽  
Wen-Yi Shi ◽  
Yi-Xuan He ◽  
Wen-Yao Hao ◽  
Kai-Yue Ma ◽  
...  
Keyword(s):  
Lignocellulosic Biomass ◽  
Industrial Application ◽  
Submerged Fermentation ◽  
Enzyme Production ◽  
Laccase Activity ◽  
White Rot Fungi ◽  
White Rot ◽  
Pleurotus Pulmonarius ◽  
Toona Sinensis ◽  
Sorghum Straw

The capacity of novel isolated white-rot fungi secreting laccase was evaluated for various kinds of lignocellulosic biomass in submerged fermentation. The laccase secreted by Neofomitella fumosipora Han 386 and Pleurotus pulmonarius Han 527 was significantly faster than that by Coriolopsis trogii Han 751 and Coriolopsis sanguinaria An 282. Maximum laccase from N. fumosipora Han 386 on the four kinds of lignocellulosic biomass tested appeared on the first day. This phenomenon indicated that N. fumosipora Han 386 secreted laccase rapidly compared with other tested strains in this study and showed the superiority in the rate of secreting laccase. Based on the maximum laccase activity, the ability of secreting laccase of C. sanguinaria An 282 was superior to other tested novel isolated strains. On the whole, N. fumosipora Han 386 and P. pulmonarius Han 527 preferred Toona sinensis to produce laccase, C. trogii Han 751 preferred to produce laccase on Populus beijingensis, and C. sanguinaria An 282 grown on Sorghum straw was more suitable for secreting laccase. The results will be helpful for developing bioprocesses using various kinds of lignocellulosic biomass for lignocellulolytic enzyme production and enlarging the number of laccase producing strains for industrial application.

KINETIC AND ENZYME RECYCLING STUDIES OF IMMOBILIZED b-GLUCOSIDASE FOR LIGNOCELLULOSIC BIOMASS HYDROLYSIS

2018 ◽  
Vol 17 (6) ◽  
pp. 1385-1398 ◽  
Author(s):  
Deepak K. Tuli ◽  
Ruchi Agrawal ◽  
Alok Satlewal ◽  
Anshu S. Mathur ◽  
Ravi P. Gupta ◽  
...  
Keyword(s):  
Lignocellulosic Biomass ◽  
Biomass Hydrolysis ◽  
Enzyme Recycling

L-asparaginase, acrylamide quenching enzyme production from leaves of Tamarindus indica and seeds of Vigna radiata–Fabaceae

2019 ◽  
Vol 52 (1) ◽  
Author(s):  
Ambreen Aisha ◽  
Muhammad Anjum Zia ◽  
Muhammad Asger ◽  
Faqir Muhammad
Keyword(s):  
Vigna Radiata ◽  
Enzyme Production ◽  
Tamarindus Indica ◽  
Acrylamide Quenching
Sign in / Sign up

Export Citation Format

Share Document