10 results about "Enzymic degradation" patented technology

The application belongs to the technical field of bioengineering, and particularly relates to a xanthan gum cleavage ancestral enzyme AncXLY196 based on ancestral sequence reconstruction, an amino acid sequence of which is shown as SEQ ID NO. 2. Based on the xanthan gum cleavage ancestral enzyme, a mutant AncXLY196-X7 is further obtained, an amino acid sequence of which is shown as SEQ ID NO. 4, xanthan gum degradation activity of which reaches 2.5 times of that of the xanthan gum cleavage ancestral enzyme, and the optimal catalytic temperature of the xanthan gum cleavage ancestral enzyme and the mutant thereof is increased to 45 DEG C, and the enzyme activity of the mutant of the xanthan gum cleavage ancestral enzyme is reserved by 50-80% after being treated at 45-55 DEG C for 12-24 h. The application provides a new enzyme resource for efficient enzymatic degradation of xanthan gum and preparation of functional oligosaccharides.

The invention relates to the technical field of biological catalysis engineering, and discloses a method for preparing enteromorpha oligosaccharide through composite enzymatic hydrolysis gradient alcohol precipitation, which comprises the following steps: in the enzymatic hydrolysis reaction process, establishing negative feedback coupling between stirring power and ethanol concentration increase operation, characterizing the consumption degree of a non-liquid-phase substrate in real time by using the stirring power, and calculating the concentration of the enteromorpha oligosaccharide. According to the present invention, the strong coupling relationship between the chemical reaction and the physical phase change is established, such that the enzymolysis is converted from the random collision process to the physical phase equilibrium-dominated deterministic ordered evolution process so as to achieve the selective precipitation and degradation of the product; and the capability of the system for automatically adapting to the raw material difference is improved, and the technical problems of disordered reaction and poor product selectivity in the existing enzymatic degradation are solved.

The present application relates to the technical field of biological catalysis engineering, and discloses a method for preparing Enteromorpha oligosaccharides by composite enzymolysis gradient alcohol precipitation, which comprises the following steps: in the process of enzymolysis reaction, a negative feedback coupling between stirring power and the increase operation of ethanol concentration is established, the stirring power is used to represent the consumption degree of non-liquid substrate in real time, and the increase of ethanol is triggered on the basis, so that the phase equilibrium is dynamically regulated, and the selective precipitation and degradation of products are realized. By establishing a strong coupling relationship between chemical reaction and physical phase change, the present application changes the random collision process of enzymolysis into a deterministic and orderly evolution process dominated by physical phase equilibrium, and improves the ability of the system to adapt to the differences in raw materials, thereby solving the technical problems of reaction disorder and poor product selectivity in the existing enzymatic degradation.

This invention discloses a BhrPETase keratinase mutant and its application in the degradation of polyethylene terephthalate (PET), belonging to the fields of environmental science and enzyme engineering. The site numbers are based on the amino acid sequence shown in SEQ ID NO:1. The mutant contains substitutions of S14G, H78Y, and S184G relative to SEQ ID NO:1, with the preferred amino acid sequence shown in SEQ ID NO:9. Under conditions of 1 mg enzyme protein / g substrate, 65°C, and 96 h, the preferred mutant exhibits a degradation rate of 90.4% for PET membranes and a half-life of 150 h at 60°C, making it suitable for enzymatic degradation and depolymerization of PET.

A C-terminal truncated alginate lyase and its application. This invention belongs to the fields of bioengineering, genetic engineering, and enzyme engineering, and relates to a C-terminal truncated alginate lyase TY2 designed with molecular docking assistance, its encoding gene, recombinant vector, strain, and its application in the preparation of low-polymerization degree alginate oligosaccharides. Using wild-type MhAly6 as the parent, the truncation boundary was determined through structural prediction and molecular docking. A portion of the linker peptide was retained, and the C-terminal GH28 family domain was deleted to obtain the truncated form TY2. TY2 has approximately twice the specific activity of the wild-type enzyme, and even higher residual activity after incubation at 45°C for 1 hour, achieving a synergistic improvement in catalytic activity and thermal stability. + The relative enzyme activity reached 4.3 times that of the control group, which can degrade pretreated Sargassum powder. The product is mainly ΔDP2–ΔDP4 low-polymerization brown algae oligosaccharides, which are suitable for related enzymatic degradation and oligosaccharide preparation.

This invention belongs to the field of environmental science and relates to a method for the complete depolymerization of thermoplastic polyester polyurethane (PBA-PU) using a dual-enzyme approach. Specifically, PBA-PU is used as a substrate, and esterases PETase and Aes72 are added to initiate the depolymerization reaction. PETase hydrolyzes the ester bonds, while Aes72 primarily hydrolyzes the carbamate bonds. The two enzymes synergistically promote the complete depolymerization of PBA-PU. This invention utilizes a dual-enzyme approach to degrade PBA-PU, improving enzymatic hydrolysis efficiency while completely depolymerizing PBA-PU into the monomer MDA. The monomers generated after depolymerization can then be repolymerized or utilized for other high-value applications, thereby improving product utilization and enhancing the competitive advantage of enzymatic degradation of PBA-PU.

The invention discloses an enzymolysis gleditsia sinensis saponin-copper chelate as well as a preparation method and application thereof in prevention and treatment of citrus canker, and belongs to the technical field of crop prevention and treatment. The preparation method comprises the following steps: extracting gleditsia sinensis saponin, purifying the gleditsia sinensis saponin, carrying out enzymatic degradation on the gleditsia sinensis saponin, and then adding CuSO4. 5H2O to carry out chelation reaction to obtain the enzymolysis gleditsia sinensis saponin-copper chelate. The initial contact angle of an aqueous solution of the chelate on citrus leaves is small, the chelate can be rapidly wetted and spread on the leaves, the deposition effect is good, the chelate has excellent leaf adhesion performance and anti-scouring capacity, meanwhile, the enzymolysis gleditsia sinensis saponin-copper chelate has excellent inhibitory activity on xanthomonas carpesium, and the enzymolysis gleditsia sinensis saponin-copper chelate can be used for preparing the citrus leaf-copper chelate. The compound can be used as a green, environment-friendly, safe and efficient bactericide, and has excellent application potential in the aspect of citrus canker prevention and control.

The invention belongs to the technical field of biochemistry, and particularly discloses an algal polysaccharide degradation method, a degradation product and application of the degradation product. According to the method provided by the invention, sodium persulfate (Na2S2O8) is taken as an oxidizing agent, and the low-molecular-weight active polysaccharide is prepared by efficiently cracking a polysaccharide chain through a free radical chain reaction. Compared with a traditional chemical degradation method, a physical degradation method or an enzymatic degradation method, the method has the advantages that the degradation efficiency is obviously improved, the uniformity of degradation products is high, the process compatibility is strong, and the cost is low. Polysaccharide degradation products with different molecular weights can be obtained by adjusting the concentration of sodium persulfate, the degradation temperature and the degradation time, and an efficient and controllable scheme is provided for industrial production of low-molecular-weight active polysaccharides. The obtained algal polysaccharide degradation product can be used for preparing drugs for improving intestinal microecological balance and relieving and / or treating colitis, can repair intestinal mucosa structures, promote inflammatory cell regression, reduce proinflammatory factor expression and the like, and has potential clinical application potential.

This invention relates to a method for degrading PET fibers using a mechanical enzymatic method and recycling the degradation products, comprising: (1) extracting crude enzyme solution using screened PET-degrading strains. When the bacteria are in the late logarithmic growth phase, the supernatant of the culture medium is collected by centrifugation, and then placed in a freeze dryer to remove water from the crude enzyme solution, thereby obtaining the desired enzyme powder. (2) accurately weighing a certain amount of PET and placing it in a homogenizer, adding a certain amount of enzyme powder and sodium phosphate buffer with added green surfactant, performing preliminary mechanical treatment using a homogenizer, and then incubating the treated mixture at a constant temperature. (3) reacting the degradation products in the solid reaction mixture with sodium carbonate solution, filtering through cotton, and then acidifying with hydrochloric acid to precipitate substances such as terephthalic acid. Finally, centrifuging is used to remove the acidic supernatant to separate the degradation products such as terephthalic acid. This process avoids the use of large amounts of solvent, reduces costs and environmental impact, realizes the direct enzymatic hydrolysis of highly crystalline PET fibers, and simultaneously achieves high-purity recovery of degradation products, which can be recycled for the production of new PET products.

The application discloses an enzymatic Gleditsia japonica saponin-copper chelate, a preparation method thereof and application thereof in the prevention and treatment of citrus canker, and belongs to the technical field of crop prevention and treatment. The Gleditsia japonica saponin is extracted, purified and degraded by an enzyme method, CuSO4*5H2O is added to perform a chelation reaction, and the enzymatic Gleditsia japonica saponin-copper chelate is obtained. The initial contact angle of the aqueous solution of the chelate on citrus leaves is small, the aqueous solution can rapidly wet and spread on the leaves, the deposition effect is good, the chelate has excellent leaf adhesion and anti-washing capacity, the enzymatic Gleditsia japonica saponin-copper chelate has excellent inhibitory activity on Xanthomonas axonopodis, can be used as a green, environmentally-friendly, safe and efficient bactericide, and has excellent application potential in the prevention and treatment of citrus canker.