Fermentation method for producing high-activity acidic cellulase from trichoderma reesei

Abstract

The invention provides a fermentation method for producing high-activity acid cellulase from trichoderma reesei, which comprises the following steps: S1, inoculating a trichoderma reesei strain into a culture medium, separating to obtain a single colony, culturing seeds, and preserving; s2, inoculating the preserved trichoderma reesei into an activated culture medium for culturing; S3, inoculating the culture solution in the step S2 into a seed amplification culture medium for culturing; and S4, inoculating the culture solution in S3 into a fermentation culture medium, and carrying out liquid submerged fermentation to obtain fermentation liquor containing acidic cellulase. According to the method, culture medium components and fermentation conditions are optimized, sophorose is used for inducing enzyme production, trichoderma reesei cellulase production is divided into two stages, the feeding speed in the enrichment period is increased as much as possible so that thalli are rapidly proliferated to 30% of wet weight, after the thalli density is reached, the feeding speed is reduced, the thalli enter the induced enzyme production period, glucose is rapidly consumed, the low-concentration sophorose is transferred into cells to play a strong induction role, so that the high-activity acidic cellulase is obtained in fermentation liquor.

Description

technical field [0001] The invention belongs to the technical field of bioengineering, and in particular relates to a fermentation method for producing highly active acid cellulase by Trichoderma reesei. Background technique [0002] Acid cellulase is a compound enzyme, which refers to the general term for multi-component enzymes that can participate in cellulose degradation under acidic conditions. According to its enzyme system, it can be divided into: endo-β-1,4-glucanase, Exo-β-1,4-glucanase, β-1,4-glucosidase three categories, widely used in feed industry, pulp and paper, textile industry, food brewing, bio-energy and wastewater treatment, etc. in the field. Microbial fermentation produces acid cellulase, which is widely used in industrial production due to its advantages of simple cultivation, low price, wide source and high yield. Among the microorganisms producing acid cellulase, Trichoderma reesei is a safe cellulase producing bacteria, and the research is more in...

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Problems solved by technology

[0003]In recent years, there have been many researches on the production of acid cellulase by microbial fermentation in my country, but the expression of bacteria has not been significantly improved, and the activity of acid cellulase has not been improved. Compared with foreign cellulase preparations, the difference is far, so that the acid cellulase used in my country's industrial production mainly depends on imports.

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