54 results about "Tryptic hydrolysis" patented technology

The present invention relates to a refining process of Ganoderma lucidum polysaccharide, which is prepared from dried Ganoderma lucidum by pulverizing and sieving, ultrasonic extracting polysaccharide, trypsin hydrolyzing protein impurities, cation exchange resin deenzyme, forward osmotic membrane treatment, spray drying and other technological steps, so as to obtain refined Ganoderma lucidum polysaccharide. Protein impurities in Ganoderma polysaccharide extract are hydrolyzed with single trypsin, the isoelectric point of trypsin is high than that optimum reaction pH, and after enzymatic hydrolysis, a cation exchange resin is directly used to deenzyme, thus eliminating the need to adjust pH value again, and the process is simple. The deenzymatic polysaccharide extract is filled with 100-fold water-absorbent grafted starch and treated with forward osmotic membrane with molecular weight cut-off of 5000Da. The proteolytic peptides are removed at the same time of concentration. The separation efficiency is high and the energy consumption is low. The trypsin enzymatic hydrolysis, cation exchange resin deenzyme and forward osmosis membrane treatment are carried out in series, which can not only completely remove protein impurities and achieve high purity of polysaccharide, but also mild deproteinization conditions and stable structure of polysaccharide can be achieved.

The invention provides a method for preparing exorphins from soybean protein isolate by fractional hydrolysis, which relates to a method for preparing exorphins. The invention solves the problem that the traditional exorphins preparing method has high preparing cost and is easy to produce harmful substances in the preparing process. The method 1: after being hydrolyzed, the pepsin is hydrolyzed by trypsin, acid protease, alkaline protease or neutral protease; the method 2, after being hydrolyzed, the trypsin is hydrolyzed by pepsin, acid protease, alkaline protease or neutral protease; the method 3, after being hydrolyzed, the alkaline protease is hydrolyzed by pepsin, trypsin, acid protease or neutral protease; the method 4, after being hydrolyzed, the neutral protease is hydrolyzed by pepsin, trypsin, acid protease or alkaline protease; and the method 5, after being hydrolyzed, the acid protease is hydrolyzed by pepsin, trypsin, alkaline protease or neutral protease. The invention has low cost, and does not produce harmful substances in the preparing process.

The invention discloses a preparation method of a whey protein peptide with antibacterial activity, and relates to the technical field of biology. The preparation method comprises steps of preprocessing, enzymolysis, separation and purification, wherein the purification step adopts a simulated mobile chromatography separation method for industrial production of the coarse whey protein peptide after separation, and the whey protein peptide with antibacterial activity is obtained. According to the preparation method, trypsin is adopted to hydrolyze the whey protein to prepare the peptide with antibacterial activity, so that deep processing of the whey protein is realized; the process of the preparation method is simple, the antibacterial activity of the hydrolysis product is high, and the preparation method is suitable for industrial popularization and production; the method is high in automation degree, low in production cost and high in extraction efficiency, and the antibacterial peptide prepared with the method not only has more remarkable bacteriostatic effect, but also is safe and nutritional, provides a reliable base material or ingredient for development of a natural preservative agent, can increase the weight of preservative products of China and improve the safety of the preservative products of China, and meets the requirement of market development of natural food additives.

The invention provides a preparation method of chlorella anti-tumor polypeptide, which is characterized in that firstly, the chlorella protein is extracted by using a low-temperature ultra-high pressure continuous flow cell crusher, and then the chlorella protein is hydrolyzed by trypsin, filtered by an ultrafiltration centrifuge tube, and obtained Chlorella polypeptides with molecular weights ranging from 0-3KD, 3-5KD, 5-10KD and greater than 10KD. The chlorella polypeptide prepared by the present invention has anti-tumor activity, for example, it has a certain inhibitory effect on the growth of human liver cancer cell HepG2 in vitro. The cell (HepG-2) growth inhibition rates in vitro reached 7%, 14% and 10%, respectively, which is conducive to the development and utilization of anti-tumor health food and pharmaceutical products.

The invention belongs to the technical field of analysis, and relates to a method for absolutely quantifying mass spectrum of histidine tag-containing recombinant human endostatin. The method is based on LC-MS / MS, and extracts histidine tag-containing recombinant human endostatin from a plasma sample through utilizing Ni<2+> sepharose gel resin, and realizes absolute quantification of histidine tag-containing recombinant human endostatin in the plasma sample through utilizing a quantifying strategy for a specific peptide generated during hydrolysis of recombinant human endostatin with trypsin and taking a synthetic peptide having a sequence similar to that of the specific peptide as an interior label. The invention mainly includes a biological sample preparation method, an LC-MS / MS measuring method, standard curve preparation and precision degree measurement. The method has good linear relation, high accuracy degree and excellent reproducibility, and can be used for measuring the blood concentration of histidine tag-containing recombinant human endostatin and studying the pharmacokinetics.