5results about How to "Stable passage" patented technology

The application belongs to the technical field of biology and particularly relates to an African swine fever virus pNP868R protein monoclonal antibody and a preparation method and application thereof. The application takes the pNP868R protein prepared by eukaryotic expression as an antigen, immunizes BALB / c mice, uses hybridoma technology, and obtains a hybridoma cell line capable of stably secreting the anti-African swine fever virus pNP868R protein monoclonal antibody through cell fusion, indirect ELISA method screening, limited dilution method subcloning and hybridoma continuous passage culture. The application also obtains an African swine fever virus pNP868R protein monoclonal antibody. The monoclonal antibody has high affinity with the pNP868R protein and can be applied in Western-Blot experiments, indirect immunofluorescence experiments, immunoprecipitation experiments and the capture of proteins interacting with pNP868R, and can be used for the diagnosis, prevention or treatment of African swine fever.

This disclosure belongs to the field of cell culture technology, and specifically relates to a serum-free culture medium for MSCs and its preparation method. The culture medium contains a fixed ratio of basic nutrients and six key regulatory factors, namely transferrin, ascorbic acid, human serum albumin, human fibroblast growth factor rhFGF, platelet-derived growth factor PDGF-BB, and transforming growth factor TGF-β1. By optimizing the combination and concentration of these six key regulatory factors, the proliferation rate and activity of MSCs are significantly improved. It also provides four suitable formulations: high proliferation, high activity, balanced, and economical. The culture effect is stable and reproducible, with high safety and a simple process, making it suitable for laboratory research and large-scale clinical-grade MSC culture.

The application provides a proliferation culture medium for long-term stable passage of bovine cells, a method for promoting long-term stable passage of bovine cells and application. The components of the proliferation culture medium include complete culture medium, cycloastragenol and metformin hydrochloride. Research shows that the proliferation culture medium can make bovine fetal fibroblasts (BFFs) break through the proliferation limit in the process of in-vitro passage culture, form a continuous cell line, and be beneficial to the production of cell culture meat products of excellent quality. The culture medium provided by the application can support the continuous passage of BFFs to 145 generations, and the cell type of the bovine fetal fibroblast cell line passed to 145 generations is unchanged, having the advantage of long-term stable passage. The induction by the proliferation culture medium can make BFFs break through the aging limit, realize long-term stable passage (≥100 generations) and maintain a positive rate of >90% of vimentin, meet the demand of cell culture meat mass production for the number of cells, and have very broad application prospects.

This invention provides a *Chitozobacterium mangroveense* FCG-7 strain and its application in the preparation of N-acetylglucosamine, belonging to the field of microbial technology. The *Chitozobacterium mangroveense* FCG-7 strain provided by this invention is deposited at the Guangdong Provincial Microbial Culture Collection Center, with accession number GDMCC No: 63488. This strain exhibits good low-temperature resistance and the ability to produce extracellular chitinase, enabling it to efficiently degrade chitin under low-temperature conditions to produce N-acetylglucosamine with excellent biological effects. Furthermore, this strain remains stable after subculturing and holds promise for application in the production of high-value-added N-acetylglucosamine from chitin-based biomass under low-temperature conditions.

The application discloses screening of aspergillus oryzae with high yield of mycelial protein and application thereof, and belongs to the technical field of fermentation engineering. The aspergillus oryzae strain WL03 with high spore production capacity, good adaptability, stable subculture, and high mycelial concentration and mycelial protein content is screened, the culture medium for aspergillus oryzae fermentation is optimized, and the scale-up culture is further carried out in a 5L fermenter and a 20L fermenter. The strain of the application achieves the effects of 21g / L mycelial concentration and 46% mycelial protein content in the 5L fermenter, and achieves the effects of 20g / L mycelial concentration and 46% mycelial protein content in the 20L fermenter, and has the industrial application potential.