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CN-118579802-B - Clay modification method and application thereof

CN118579802BCN 118579802 BCN118579802 BCN 118579802BCN-118579802-B

Abstract

The invention belongs to the technical field of microbial fermentation, and particularly provides a clay modification method which comprises the following steps of (1) crushing clay, sieving, adding long-chain fatty acid into the sieved clay for reaction, filtering, washing and drying to obtain primary modified clay, (2) adding inorganic acid and fatty amine into the primary modified clay for reaction, filtering, washing and drying after reaction to obtain secondary modified clay, and (3) adding water into the secondary modified clay, and baking to obtain modified clay. And provides a method for producing cellulase by using the modified clay, the immobilized Trichoderma reesei and the immobilized Trichoderma reesei based on the method. Trichoderma reesei cannot enter fermentation liquor after being fixed by the modified clay, but metabolic products of the Trichoderma reesei can be gradually dissolved in the fermentation liquor, so that separation of thalli and the fermentation liquor is realized, mass transfer resistance in a fermentation process is reduced, post-treatment process pressure is reduced, cost is reduced, and the modified clay can be reused in new batch of trichoderma reesei seed immobilization.

Inventors

  • RAO JIANJUN
  • ZHANG LI
  • ZHOU XIANG
  • LI CHAO
  • WANG QIJUN
  • ZHANG CHENGJIE

Assignees

  • 武汉新华扬生物股份有限公司

Dates

Publication Date
20260512
Application Date
20240625

Claims (10)

  1. 1. A clay modification method, characterized by comprising the steps of: (1) Crushing clay, sieving, adding long-chain fatty acid into the sieved clay for reaction, and filtering, washing and drying after the reaction to obtain primary modified clay, wherein the long-chain fatty acid is one or more of oleic acid, linoleic acid, stearic acid, linolenic acid, palmitic acid and myristic acid; (2) Adding inorganic acid and fatty amine into the primary modified clay to react, filtering, washing and drying after the reaction to obtain secondary modified clay, wherein the inorganic acid is one or more of hydrochloric acid, nitric acid, sulfuric acid and perchloric acid; (3) Adding water into the secondary modified clay, and baking to obtain the modified clay.
  2. 2. The method for modifying clay according to claim 1, wherein in the step (1), a long-chain fatty acid solution having a mass concentration of 3 to 5% is added to the clay after sieving, and a solid-liquid ratio of the clay to the long-chain fatty acid solution is1 (5 to 7).
  3. 3. The method for modifying clay according to claim 1, wherein the step (2) comprises adding an aliphatic amine solution with a mass concentration of 3-5% to the primary modified clay in a mass ratio of 1:3:3, wherein the mass ratio of the inorganic acid is 0.02-0.05 mol/L.
  4. 4. The clay modification method according to claim 1, wherein the reaction temperature in step (1) and step (2) is 70-80 ℃ and the reaction time is 16-24 hours.
  5. 5. A modified clay, characterized in that the modified clay is prepared by the clay modification method according to any one of claims 1 to 4.
  6. 6. An immobilized Trichoderma reesei comprising Trichoderma reesei and the modified clay according to claim 5.
  7. 7. The immobilized Trichoderma reesei of claim 6, comprising a modified clay and Trichoderma reesei seed solution in a solid-to-liquid ratio of 1:2-3.5.
  8. 8. A method for producing cellulase by immobilized Trichoderma reesei, which is characterized by adopting the immobilized Trichoderma reesei of any one of claims 6-7, and specifically comprising the following steps: (1) Preparing a fermentation medium; (2) Adding the immobilized Trichoderma reesei into a fermentation medium for fermentation to produce cellulase.
  9. 9. The method for producing cellulase by immobilized Trichoderma reesei of claim 8, wherein the amount of the immobilized Trichoderma reesei added in the step (2) is 3-5% based on the amount of the fermentation medium.
  10. 10. The method for producing cellulase by immobilized Trichoderma reesei of claim 8, wherein the feeding is started when the dissolved oxygen amount in the fermentation process of the step (2) is reduced to the minimum and rebounds to more than 50%, and the dissolved oxygen amount in the feeding is controlled to be 10-20%.

Description

Clay modification method and application thereof Technical Field The invention belongs to the technical field of microbial fermentation, and particularly relates to a clay modification method and application thereof. Background Cellulase is a complex enzyme system consisting of exoglucanase, endoglucanase and beta-glucanase. The cellulase enzyme system produced by Trichoderma reesei is complete and the enzyme activity is stable. However, in the fermentation process of Trichoderma reesei, when the thallus quantity is too large, the phenomenon of viscous fermentation liquid can occur, and the fermentation mass transfer process is influenced, so that the fermentation enzyme activity can not reach a higher level. Meanwhile, after fermentation, the post-treatment process of the fermentation liquid can generate larger resistance due to thallus, so that the post-treatment process is influenced, and the fermentation cost is increased. Disclosure of Invention The invention aims to solve the problems that the fermentation enzyme activity can not reach a higher level and the post-treatment process cost is high in the prior art due to the excessive growth of Trichoderma reesei in the later fermentation period. For this purpose, the invention provides a clay modification method, which comprises the following steps: (1) Crushing clay, sieving, adding long-chain fatty acid into the sieved clay for reaction, filtering, washing and drying after the reaction to obtain primary modified clay; (2) Adding inorganic acid and fatty amine into the primary modified clay for reaction, filtering, washing and drying after the reaction to obtain secondary modified clay; (3) Adding water into the secondary modified clay, and baking to obtain the modified clay. Specifically, in the step (1), a long-chain fatty acid solution with the mass concentration of 3-5% is added into the sieved clay, and the solid-liquid ratio of the clay to the long-chain fatty acid solution is 1:5-7. Specifically, in the step (2), 0.02-0.05 mol/L of inorganic acid and 3-5% of fatty amine solution are added into the primary modified clay according to the mass ratio of 1:3:3. Specifically, the reaction temperature in the step (1) and the step (2) is 70-80 ℃ and the reaction time is 16-24h. The invention also provides modified clay, which is prepared by adopting the clay modification method. The invention also provides an immobilized Trichoderma reesei, which comprises the Trichoderma reesei and the modified clay. Specifically, the immobilized trichoderma reesei comprises modified clay and trichoderma reesei seed solution with a solid-to-liquid ratio of 1:2-3.5. The invention also provides a method for producing cellulase by immobilized Trichoderma reesei, which adopts the immobilized Trichoderma reesei and specifically comprises the following steps: (1) Preparing a fermentation medium; (2) Adding the immobilized Trichoderma reesei into a fermentation medium for fermentation to produce cellulase. Specifically, the amount of the immobilized Trichoderma reesei added in the step (2) is 3-5% based on the amount of the fermentation culture medium. Specifically, when the dissolved oxygen amount in the fermentation process of the step (2) is reduced to the minimum and rebounded to more than 50%, starting material feeding, wherein the dissolved oxygen amount in the material feeding process is controlled to be 10-20% Compared with the prior art, the invention has the following advantages and beneficial effects: According to the clay modification method provided by the invention, the wettability and other properties of the clay are modified, and the obtained modified clay can be used as an immobilization material to immobilize Trichoderma reesei seed liquid on the modified clay, so that the modified clay can be applied to Trichoderma reesei fermentation. Because of the specificity of the immobilized Trichoderma reesei, the Trichoderma reesei cannot enter the fermentation liquid, but the metabolite of the Trichoderma reesei can be gradually dissolved in the fermentation liquid, so that the separation of thalli and the fermentation liquid is realized, the mass transfer resistance in the fermentation process can be reduced, and the fermentation process can be normally carried out. Meanwhile, the pressure of the post-treatment process can be reduced, the total fermentation cost is reduced, and the problem of excessive growth of trichoderma reesei in the later period of fermentation is solved. And taking out the modified clay blocks after fermentation is finished, thus obtaining the cellulase fermentation liquid, and the modified clay blocks can be reused for immobilization of a new batch of Trichoderma reesei strain. Detailed Description The technical solutions of the present invention will be clearly and completely described in the following examples, and it is obvious that the described examples are only some examples of the present invention, but not all examples. Although repr