9results about How to "Efficient hydrolysis" patented technology

This invention discloses a chitin endonuclease gene, recombinant vector, recombinant bacteria, recombinant enzyme, preparation method, and applications of high expression of Poria cocos chitin endonuclease. The nucleotide sequence of the gene is shown in SEQ ID No. 1. The nucleotide sequence shown in SEQ ID No. 1 can be used to achieve high-level recombinant secretory expression of the target protein in Pichia pastoris host bacteria using a Pichia pastoris inducible expression vector. Under high-density fermentation conditions, the total secretory expression level of the target protein can reach 10.7 g / L. The recombinant enzyme is purified by DEAE ion exchange chromatography, and this recombinant enzyme can efficiently hydrolyze colloidal chitin to produce chitin oligosaccharides. The recombinant Poria cocos chitin endonuclease prepared by this invention has important application value and broad application prospects in the preparation of functional chitosan oligosaccharides, antibacterial, antitumor, environmental protection, and agriculture.

The application provides a recombinant polymyxin enzyme and a preparation and application method thereof, an amino acid sequence of the recombinant polymyxin enzyme is shown as SEQ ID NO. 1, and the recombinant polymyxin enzyme is obtained through site-directed mutation on an amino acid sequence of a wild-type polymyxin enzyme derived from Brevibacillus laterosporus. The recombinant polymyxin enzyme can specifically recognize and cut a peptide bond between a tripeptide side chain and a cyclic heptapeptide ring in a polymyxin structure and a peptide bond between threonine and diaminobutyric acid inside the cyclic heptapeptide ring, and further can specifically degrade or neutralize the recombinant polymyxin enzyme of polymyxin.

The invention discloses a preparation method and application of an enzyme preparation for enzymatically hydrolyzing bitter substances in citrus juice. Using Aspergillus tabingensis UA13 isolated in the early stage of the laboratory and mutagenized by atmospheric and room temperature plasma (ARTP) as the starting strain, limonin in lemon peel powder is used as an inducer to induce enzyme production, and the fermentation enzyme production process of the strain and the substrate affinity of the enzyme are studied. The results show that: in a 1 L fermentor medium, under the optimal conditions of limonin addition amount of 4.0 mg / L, inoculation amount of 10% (v / v), initial pH value of 5.0, stirring speed of 250 rpm, and fermentation at 30 °C, the highest limonin debittering enzyme activity can reach 48.52 U / mL. The results of the study on the substrate affinity of the enzyme for limonin show that the Km value of the limonin debittering enzyme for limonin is 0.622 mmol / L, indicating strong affinity. At the same time, the enzyme can still efficiently hydrolyze other bitter substances such as naringin and hesperidin, has good heat resistance and acid resistance, and has very good application effects in the citrus juice processing industry.

This invention discloses a method and application for treating moldy corn to synthesize polyhydroxy fatty acids (PHA) using a compound enzyme preparation, relating to the fields of fermentation engineering and waste resource utilization technology. The method for treating moldy corn to synthesize PHA using a compound enzyme preparation includes the following steps: 1) screening and culturing highly efficient halophilic bacteria as inoculum strains for open-enzyme PHA synthesis; 2) pretreating moldy corn with a compound enzyme preparation composed of α-amylase, β-amylase, and glucoamylase; 3) using the moldy corn hydrolysate as a fermentation carbon source, inoculating with PHA-producing halophilic bacteria for open-enzyme fermentation. This invention constructs a complete process system of specific halophilic bacteria screening – moldy corn enzymatic pretreatment – ​​open-enzyme fermentation to synthesize PHA, realizing the resource utilization and high-value utilization of moldy corn. Compared with existing technologies, it has significant economic, environmental, and industrial value, with outstanding comprehensive beneficial effects.

The invention relates to the technical field of anaerobic digestion of crop straw raw materials, and particularly discloses a method for strengthening anaerobic methanation of crop straw based on biological micro-aerobic pretreatment combined with a microbial electrolysis cell. According to the method, crop straw is placed in a closed system added with calcium peroxide (CaO2) and inoculated sludge for biological micro-aerobic pretreatment. A micro-aerobic environment created by CaO2 is utilized to stimulate facultative hydrolytic bacteria to enrich and secrete a large amount of hydrolase, and the lignocellulose structure of the straw is efficiently cracked. After pretreatment, the system is transferred into a microbial electrolysis cell reactor, inhibition of residual oxidizing substances in pretreatment on methanogenic archaea is effectively eliminated by utilizing a cathode reduction effect, and meanwhile, electron transfer and methanogenic metabolism paths of the system are enhanced. Through a coupling strategy of'biological micro-aerobic pretreatment + microbial electrolysis cell ', synergistic improvement of hydrolysis and methanation processes is realized, and an innovative and feasible solution is provided for efficient anaerobic digestion of crop straws to produce methane.

The invention provides a method for simultaneously recovering neopentyl glycol, sodium butyrate and n-butyl alcohol, according to the method, polyol wastewater containing natural sodium hydroxide is used as the only hydrolysis alkali source of neopentyl glycol heavy component waste liquid, and efficient hydrolysis of esters in the neopentyl glycol heavy component waste liquid can be realized without adding any additional alkali agent; neopentyl glycol, sodium butyrate and n-butyl alcohol in the hydrolysate are simultaneously recovered through ozone oxidation, distillation, rectification and the like, so that an integrated process of'alkali source internal circulation-multi-component synergistic conversion-gradient separation and purification 'is realized. In the invention, the recovery rate of neopentyl glycol is greater than or equal to 85%; meanwhile, the purity of neopentyl glycol is greater than or equal to 97%, the purity of sodium butyrate is greater than or equal to 95%, and the purity of n-butyl alcohol is greater than or equal to 98%, all reach the industrial-grade raw material standard, and can be directly sold or reused for production.

The invention provides lactobacillus plantarum with high beta-glucosidase activity and application of the lactobacillus plantarum, and belongs to the technical field of microbial fermentation. The lactobacillus plantarum with the high beta-glucosidase activity, provided by the invention, comprises lactobacillus plantarum (Lactobacillus plantarum) LZU-J-LZ1-2 or Lactobacillus plantarum (Lactobacillus plantarum) LZU-J-QA5-2, and the lactobacillus plantarum with the high beta-glucosidase activity, the beta-glucosidase activity, the beta-glucosidase activity, the beta-glucosidase activity and the beta-glucosidase activity, and the beta-glucosidase activity and the beta-glucosidase activity of the beta-glucosidase activity and the beta-glucosidase activity of the beta-glucosidase activity are both high. The lactobacillus plantarum with high beta-glucosidase activity also has acid resistance, salt resistance and gastric juice and intestinal juice tolerance, has strong gastrointestinal tract survival potential, provides precious strain resources for developing efficient and safe multifunctional microbial preparations, and has important industrial application value.

The invention discloses application of xylanase, and belongs to the technical field of bioengineering. According to preferred codons of bacillus subtilis, a wild type xylanase (GH11 family) coding gene which is secreted by Cellulostridium morganii and is not represented is designed, and a genetic engineering technology is utilized, so that the wild type xylanase is subjected to recombinant expression in the bacillus subtilis. Through verification, the separated xylanase still has xylan hydrolysis activity under the conditions of high temperature (close to 100 DEG C) and strong alkali (pH 9-10.5), and shows good heat resistance and alkali resistance; and meanwhile, more than 60% of enzyme activity can still be maintained in a high-temperature (100 DEG C) environment within 1 hour, and the strain has relatively high thermal stability and has a good application prospect in extreme environments such as industrial production and the like.

The present application relates to the field of enzyme engineering and genetic engineering, and in particular to alpha-L-rhamnosidase BtRha78A-W435 mutant, and a preparation method and application thereof. The amino acid sequence of the mutant has one amino acid mutation with the alpha-L-rhamnosidase BtRha78A shown in SEQ ID NO. 1, and the mutation is that the tryptophan at the 435th position is mutated into lysine and arginine, respectively. The mutant of the present application has higher catalytic activity and catalytic efficiency on rutin, and has high substrate selectivity, high specificity and efficient hydrolysis of rutin, and provides theoretical guidance for industrialization of realizing green and efficient precise production of isorhamnetin with higher biological efficacy and higher bioavailability by hydrolyzing cheap and abundant rutin.