Production of cellulase in solid-state fermentation withTrichoderma reesei MCG 80 on wheat straw (original) (raw)
Related papers
Production of Cellulase for Ethanol Fermentation from Pretreated Wheat Straw
Iranian Journal of Science and Technology, Transactions A: Science, 2016
Effect of different media compositions on cellulase production was observed using a strain of Trichoderma viride. Medium with yeast extract as nitrogen source was found the best from the other sources used. Then two modes of fermentation solid state and submerged were compared for the enhanced cellulase production. Better cellulase activity was observed in submerged fermentation than the solid state fermentation. Effect of mash size and agitation was also studied. Small mash size with agitation showed higher cellulase activity than the large size pretreated wheat straw. Bacillus cellulosilyticus was also used for the cellulase production. Trichoderma produced enhanced activities of cellulase enzyme (20.738 ± 0.006 IU). Scarification of pretreated wheat straw released maximum sugar up to 16.1 g/L, after hydrolysis in 48 h using indigenously produced enzyme. The optimum conditions for the saccharification of pretreated wheat straw were 5 and 30°C for pH and temperature, respectively in 48 h. The yield of ethanol was observed 10.4 g/L in saccharified wheat straw based medium.
Applied Biochemistry and Biotechnology, 1996
Three mutants of Trichoderma reeseiwere grown in solid-state fermentation (SSF) in flasks and in a pan bioreactor. Mutant strain MCG 80 proved to be best at producing an optimal cellulase system using lignocellulosic material (wheat straw [WS]) as substrate. This preparation exhibited a ~-glucosidase activity (~GA) to FPA (FPA) ratio of about 1.0, which is indicative of a high potential for hydrolysis of cellulose. The yields of cellulase systems and the ratio of ~GA to FPA produced in flasks were comparable to that of the pan bioreactor. The cellulase system of T. reesei MCG 80 having a ratio of ~GA to FPA close to 1.0 gave the most complete (88-95%) hydrolysis of 5% delignified wheat straw (DWS). On the other hand, the cellulase system of cocultures of T. reesei QMY-1 and Aspergillus phoenicis failed to produce high hydrolytic yields in spite of having a very high ratio of ~GA to FPA (3.04). This failure was owing to the fact that coculture contained the relatively poor-quality cellulase system of the dominant organism, A. phoenicis. The resulting fermented WS can be used, as a source of enzyme (unextracted), for hydrolysis of wheat straw, and it gives increased yields of reducing sugars compared to analogous extracted enzyme preparations. The hydrolytic potential of two commercial enzymes tested were considerably lower than those of the cellulase systems produced on WS. It is evident that a complete cellulase system having a ~GA-to-FPA ratio close to 1.0 and high hydrolytic potential can be produced on lignocellulosic feedstocks in SSF.
Cellulase production using different streams of wheat grain- and wheat straw-based ethanol processes
Journal of Industrial Microbiology & Biotechnology, 2011
Pretreatment is a necessary step in the biomass-to-ethanol conversion process. The side stream of the pretreatment step is the liquid fraction, also referred to as the hydrolyzate, which arises after the separation of the pretreated solid and is composed of valuable carbohydrates along with compounds that are potentially toxic to microbes (mainly furfural, acetic acid, and formic acid). The aim of our study was to utilize the liquid fraction from steam-exploded wheat straw as a carbon source for cellulase production by Trichoderma reesei RUT C30. Results showed that without detoxification, the fungus failed to utilize any dilution of the hydrolyzate; however, after a two-step detoxification process, it was able to grow on a fourfold dilution of the treated liquid fraction. Supplementation of the fourfold-diluted, treated liquid fraction with washed pretreated wheat straw or ground wheat grain led to enhanced cellulase (filter paper) activity. Produced enzymes were tested in hydrolysis of washed pretreated wheat straw. Supplementation with ground wheat grain provided a more efficient enzyme mixture for the hydrolysis by means of the near-doubled β-glucosidase activity obtained.
Indian Journal of Biotechnology, 2006
Cellulase production studies were carried out using the fungal culture Trichoderma reesei NRRL 11460 using four different lignocellulosic residues (both raw and pre-treated) by solid-state fermentation. The effect of basic fermentation parameters on enzyme production was studied. Maximal cellulase production obtained was 154.58 U/gds when pre-treated sugarcane bagasse (PSCB) was used as substrate. The optimal conditions for cellulase production using PSCB were found to be initial moisture content - 66%, initial medium pH-7.0, incubation temperature -28°C, NH4NO3 at 0.075 M, and 0.005 M cellobiose. The optimal incubation time for production was 72 h. Results indicate the scope for further optimization of the production conditions to obtain higher cellulase titres using the strain under SSF.
Sequential cellulase production, saccharification and ethanol fermentation using rice straw
2012
This study presents alkali pretreated rice straw for cellulase production using Aspergillus niger CP1 by solid state fermentation (SSF). On 8th day, 140±2.4 IU g/l dry substrate (ds) carboxy methyl cellulose CMCase), 15±1.2 IU g/l ds filter paper activity (FPA) and 24±1.1 IU g/l ds â-glucosidase activities were noted. On extraction of 120 g material with 1 l of 0.1 mol/l citrate buffer, 5.9±0.12 IU ml/l CMCase, 0.62±0.001 IU ml/l FPA and 1.11±0.002 IU/ml â-glucosidase were obtained. When extracted enzyme was used for saccharification of 120 g fresh pretreated rice straw containing 100 g holocellulose, 45±0.2 g, sugars (50 g/l) were released in 900 ml hydrolysate to give 45% hydrolysis. Hydrolysate after yeast fermentation gave 15.6±0.05 g/l ethanol with a yield of 0.4±0.011 g/l/h and 78% fermentation efficiency. In sequential enzyme production, saccharification and fermentation studies, on 8th day of cellulase production by SSF, temperature was shifted from 28±1°C to 55°C for 36 h, ...
EXCLI journal, 2014
Bioethanol production from lignocellulosic raw materials involves process steps like pre-treatment, enzymatic hydrolysis, fermentation and distillation. In this study, wheat straw was explored as feedstock for on-site cellulase production by T. reesei 3EMS35 mutant, and as a substrate for second generation bioethanol production from baker yeast. Scanning electron microscopy (SEM) and X-ray diffractography (XRD) of untreated wheat straw (UWS) and acid treated wheat straw (TWS) were done to understand the structural organization and changes in the cellulase accessibility and reactivity. The effect of delignification and structural modification for on-site cellulase enzyme production was comparably studied. The efficiency of crude cellulase enzyme for digestion of UWS and TWS and then production of ethanol from TWS was studied using same-vessel saccharification and fermentation (SVSF) technique, both in shaking flasks as well as in fermenters. Two different methods of operation were te...
3 Biotech, 2011
Cellulose is a major constituent of renewable lignocellulosic waste available in large quantities and is considered the most important reservoir of carbon for the production of glucose, for alternative fuel and as a chemical feedstock. Over the past decade, the emphasis has been on the enzymatic hydrolysis of cellulose to glucose and the efficiency of which depends on source of cellulosic substrate, its composition, structure, pretreatment process, and reactor design. In the present study, efforts were made to produce cellulase enzyme using rice straw. The produced enzyme was used for the hydrolysis of selected lignocellulosic substrate, i.e., sorghum straw. When rice straw was used as a substrate for cellulase production under solid state fermentation, the highest enzyme activity obtained was 30.7 FPU/gds, using T. reesei NCIM 992. 25 FPU/g of cellulase was added to differently treated (native, alkali treated, alkali treated followed by 3% acid treated and alkali treated followed by 3 and 5% acid treated) sorghum straw and hydrolysis was carried out at 50°C for 60 h. 42.5% hydrolysis was obtained after 36 h of incubation. Optimization of enzyme loading, substrate concentration, temperature, time and buffer yielded a maximum of 546.00 ± 0.55 mg/g sugars (54.60 ± 0.44 g/l) with an improved hydrolysis efficiency of 70 ± 0.45%. The enzymatic hydrolyzate can be used for fermentation of ethanol by yeasts.
Elsevier, 2019
Solid-state fermentation (SSF) is a very useful modern-day tool that replenishes microbial growth on a moist surface if inert carriers and insoluble substrates are used. SSF offers several proportionate monetary as well as implementation advantages over the earlier submerged fermentation (SmF) technique that yields products with higher concentration, curtailed costs, and uncomplicated fermentation equipment, and generates reduced amounts of effluents along with a waste output that is more or less negligible. In the current scenario, SSF finds its place mostly in enzyme production as well as in organic compounds and metabolite manufacturing. Biofuel, paper, and pulp, along with detergent and textile production, show great dependence on cellulases. Endoglucanase, exoglucanase, and β-glucosidase are the three major cellulose components that can efficaciously unwind the chains of cellulose into small lignocellulose subunits and thereby produce smaller cellobiose and glucose sugar units. Different types of fungal species (filamentous, thermophilic, endophytic, etc.) are the most popular cellulase producers because they can degrade the cellulase comprehensively. A wide array of fungal species are involved in the vast production of cellulase these days with the help of this strategy because it offers lower cost with higher cellulase production.
2010
The purpose of the present work was to study the production and process parameters optimization for the synthesis of cellulase from Trichoderma viride in solid state fermentation (SSF) using an agricultural wheat straw as substrates; as fungal conversion of lignocellulosic biomass for cellulase production is one among the major increasing demand for various biotechnological applications. An optimization of process parameters is a necessary step to get higher yield of product. Several kinetic parameters like pretreatment, extraction solvent, substrate concentration, initial moisture content, pH, incubation temperature and inoculum size were optimized for enhanced production of third most demanded industrially important cellulase. The maximum cellulase enzyme activity 398.10±2.43 μM/mL/min was achieved when proximally analyzed lignocellulosic substrate wheat straw inocubated at 2% HCl as pretreatment tool along with distilled water as extraction solvent, 3% substrate concentration 40%...