Showing 4 results for Cellulase Enzyme
Volume 5, Issue 3 (9-2016)
Abstract
This study was undertaken to find out the optimum physicochemical parameters of fermentation, i.e. pH, incubation temperature and incubation time for the cellulase enzyme production of Trichoderma harzianum. The extracellular protein content was estimated by the dye binding method of Bradford. Endo-glucanase (EG), exoglucanase (or Cellobiohydrolase; CBH), β-glucosidase and total cellulase activity were investigated. The molecular weight of cellulase enzymes was studied using SDS-PAGE. To identify the predominant catalytic components in optimum conditions of enzyme production, cellulases were separated by an adapted two-dimensional electrophoresis technique. Estimated optimum conditions for cellulase enzyme were found as: pH 6.5, incubation temperature 28°C and incubation time 72 h. The SDS-PAGE profiles showed several enzyme bonds such as CBHs, EGs and BGLs. The T. harzianumhad both enzyme bonds of Cel7A (CBHI) and Cel7B (EG). Finally, the results of the 2D PAGE analysis showed that the profile of protein in optimium conditions of enzyme production had several enzymes such as CBHs, EGs and the high values of cellulose activity due to synergism that occurred between the CBH and EG.
Volume 8, Issue 3 (6-2019)
Abstract
In this study the cellulytic activity of different species of Iranian Trichoderma isolates including Trichoderma harzianum (NAS-H101), T. aureoviride (NAS-AV106), T. pleuroticola (NAS-P109), T. longibrachiatum (NAS-L110), T. ghanens (NAS-K108), T. virens (NAS- Vi114), T. atroviride (NAS-A113) and T. atroviride (NAS-A112) was studied. The extracellular protein concentration of these isolates was determined by the dye binding method of Bradford. The molecular weight of cellulase enzymes was studied using SDS-PAGE. The lowest extracellular protein production was observed in NAS-K108. The highest Endo and Exo-glucanase activity were observed in NAS-L110 and NAS-A113, respectively. The SDS-PAGE profiles had several enzyme bands such as cellobiohydrolases, endoglucanases and β-glucosidases. The NAS-K108and NAS-P109 had both enzyme bands of CBH I and CBH II, but other isolates had only a sharp enzyme band correlated to CBH I or CBH II. The highest synergy was observed in FPase of NAS-A112, that contained a large amount of Cel 6A (CBH II) and a minor amount of Cel 7B (EG I). The results indicated that NAS-A113 overproduces cellulases, ß-glycosidase, and the extracellular enzymes, which suggest that this species might be utilized as a biological agent and or a source of enzymes for cellulose degradation in colloidal cellulose.
Sanaz Noori, Parisa Hejazi,
Volume 12, Issue 1 (12-2020)
Abstract
In this study, cellulase enzyme production by Trichoderma reesei on three lignocellulosic substrates (corn bran, sawdust and wheat bran) and percentage of different combinations of sawdust and wheat bran by solid-state fermentation method for 6 days in scale checked out. Then, under optimal substrate component proportions obtained from Erlenmeyer-scale, the effect of aeration at three levels of 0.5, 1 and 1.5 liters per hour of initial dry substrate (l/(h.gds)) on the production of this enzyme in 0.5-Liter packed-bed bioreactor was studied. The initial substrate moisture and pH were 70 %(w/w) and 5 respectively, and the heating temperature was set at Erlenmeyer-scale and bioreactor at 30 and 28 °C, respectively. Cellulase enzyme production was evaluated based on the activity of endoglucanase and exoglucanase enzymes. The highest amount of endoglucanase and exoglucanase activity at substrate combination of 75% wheat bran and 25% sawdust in Erlenmeyer-scale at day 6 and 3 were obtained 13 and 6.4 U/gds, respectively, and in bioreactor at aeration of 1.5 (l/(h.gds)) at day 3 were attained 36 and 10 U/gds, respectively.
Volume 16, Issue 97 (2-2020)
Abstract
Wheat bran as a by-product of milling contain various compounds such as pentosans which have health promoting effects and functinal properties in industrial applications. In this study the extraction yield of pentosans by hot water 80oC, 0.01 mM sodium hydroxide and 2% alkaline hydrogen peroxide solutions as the conventional methods for pentosan extraction was evaluated. Then, the effects of pretreatments such as cellulase, ultrasound, autoclave and microwave in the presence of sodium hydroxide and water to increase the pentosan extraction yield were studied. Finally, in order to increase the extraction yield of the pentosans, pretreatments with the highest extraction yield (sonication, cellulase enzyme, hot water, sodium hydroxide, hydrogen peroxide) were evaluated as combined treatments. The results showed that the purity of pentosans extracted with sodium hydroxide was significantly higher than the hot water and hydrogen peroxide solution (p<0.05). Also, among the pretreatments of cellulase enzyme, ultrasound, autoclave and microwave in presence of water or sodium hydroxide, the combination of cellulase-sodium hydroxide and ultrasound-sodium hydroxide treatments resulted in the higher yields. The combined treatment of hot water (80oC)+cellulase enzyme+(0.1%)+ultrasound power (560 w, 2 minutes) and the combined treatment of hot water (80oC)+hydrogen peroxide (4%, pH=11.5) were identified respectively as the best combination factors to maximize extraction yield and pentosans purity from wheat bran.
