7 results about "Free thiol" patented technology

The present invention relates to a method for preparing a modified protein composition under conditions in which the free thiol groups of β-lactoglobulin are exposed to and modified by a reaction with an oxidized phenol compound. The resulting modified protein product (e.g., a protein-rich beverage product) has been found to have excellent performance, and in particular, it has been shown to reduce the level of unpleasant odors during sterilization heat treatment at a neutral pH and when such beverage products are consumed.

The application belongs to the field of antitumor drug preparation, and particularly relates to albumin binding and non-binding gemcitabine prodrugs, and a preparation method and application thereof. The acryloyl chloride gemcitabine prodrug is a compound formed by bridging gemcitabine and acryloyl chloride through an amide bond, and the two non-albumin binding prodrugs are compounds formed by bridging gemcitabine and 3-succinimidyl propionic acid / propionic acid through an amide bond. The ethylene group in the prodrug is a binding target for the free thiol group of the 34th cysteine on albumin, can be rapidly and specifically combined with albumin in the systemic circulation, and further forms an albumin prodrug complex. The complex can significantly improve the stability of gemcitabine in the systemic circulation, and prolong the systemic circulation time. The macromolecular prodrug strategy designed in the application can improve the delivery efficiency of chemotherapeutic drugs, improve the antitumor effect of chemotherapeutic drugs, and provides a new direction and new ideas for the delivery of chemotherapeutic drugs.

The application discloses a kind of complex and its preparation method and application, including cysteine modified chitosan and peroxidase, and cysteine modified chitosan and peroxidase form stable complex;The complex provided by the application has good stability, and particle size is uniform;The complex described in the application has simple composition, and preparation and purification method are simple, production efficiency is high, it is helpful to batch production and popularization and application, cost can be controlled, and even with high concentration of the complex described in the application and eye drop is applied to mouse or rabbit eye surface, still cannot cause eyeball anomaly by safety experiment verification;The free thiol group on the surface of cysteine modified chitosan can increase the adhesion of complex on the ocular surface, so as to overcome the limitation of rapid clearance of ocular drug, significantly prolong the residence time of peroxidase on the ocular surface, greatly improve the feasibility of peroxidase in the field of dry eye treatment application.

This invention belongs to the field of genetic engineering technology, specifically relating to a method for improving the stability of antibody-drug conjugates (ADCs) and cysteine-engineered antibodies. The invention provides a method for improving the stability of ADCs by mutating at position 14 of the first frame region of the antibody's light chain variable region to cysteine; the antibody includes Fab antibodies and / or single-chain antibodies. This invention performs a site-directed mutation at amino acid position 14 of the first frame region of the antibody's light chain variable region. This site is far from the antigen-binding interface, thus preserving antigen-binding activity while providing a modifiable free thiol group, and simultaneously reducing interchain mismatches caused by the traditional C-terminal tandem cysteine ​​residue.

This invention provides a method for preparing recombinant serum albumin with thiol preservation and conformational fidelity, relating to the field of recombinant protein preparation. Its key feature is the use of a dual protection system—low temperature and temperature control throughout the process, and specificity—to directionally protect the free thiol group at the Cys34 position and maintain the protein's native conformation. Combined with a two-stage purification process of first-stage ultrafiltration and second-stage chromatography, impurities and aggregates are efficiently removed. The final product is obtained through conformational locking and aseptic filtration. The advantages of this invention are: the recombinant serum albumin exhibits a Cys34 free thiol group retention rate ≥90%, purity ≥98%, and aggregate content ≤1%, demonstrating high activity, high stability, and high formulation compatibility. The process is animal-free, industrially scalable, and has high patent barriers, making it particularly suitable for high-end cosmetic raw materials.

The application discloses a kind of small ice wheat dough and gluten protein by enzyme modification, comprising the following steps: different adding amount Xyn, β-Glu small ice wheat dough preparation;Xyn, β-Glu and Xyn+β-Glu different adding amount on the texture determination of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu different adding amount on the determination and analysis of free thiol and disulfide bond of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu on the determination and analysis of thermal characteristics of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu on the determination and analysis of dynamic rheology and creep-recovery of small ice wheat dough;Xyn, β-Glu and Xyn+β-Glu on the influence analysis of small ice wheat gluten;Three kinds of different adding amount of enzyme all have significant difference (P<0.05) on the texture parameter of dough, the influence law of different adding amount of Xyn, β-Glu and Xyn+β-Glu on dough is basically identical, and hardness and chewiness present the trend of first falling and then rising with the increase of adding amount, wherein the hardness of 4mg / kg Xyn+40mg / kg β-Glu decreases most obviously, is 776.873±31.969g, and is reduced by 24.89% compared with small ice wheat dough without adding enzyme.

This invention discloses an oligomeric wheat peptide and its preparation method, belonging to the field of plant peptide technology. The method uses wheat bran as raw material, which undergoes extrusion puffing and ultrafine grinding pretreatment, followed by alkaline extraction combined with amylase hydrolysis to obtain a wheat bran protein extract. Subsequently, it undergoes low-temperature controlled denaturation pretreatment, followed by freeze-thaw cycles to partially unfold the protein. Cysteine ​​is added as a conformation-locking agent to form reversible mixed disulfide bonds with exposed free thiol groups to stabilize the metastable conformation. Then, site-specific enzymatic hydrolysis is performed in an ultrasound-assisted enzyme membrane reactor, with ultrafiltration separating the oligopeptides in real time. Finally, electrodialysis desalination, nanofiltration concentration, and spray drying yield high-purity wheat bran oligomeric wheat peptides with gastric mucosal protective activity. This invention achieves high-value utilization of wheat bran components, with a green and efficient process, and produces peptides with high uniformity and strong activity, significantly improving the quality and market competitiveness of wheat peptide products.