37results about How to "Good passage stability" patented technology

The invention discloses a three-dimensional simulation culture system for stem cells, and belongs to the technical field of biology. The invention solves the problems of complex operation, low efficiency, small yield and poor quality in an existing in-vitro culture of stem cells. The three-dimensional simulation culture system for the stem cells comprises a stem cell nest, a heart region first peristaltic pump, a lung region, a kidney region, a spleen region, a stomach region, a liver region, a first fluid pressure gauge, a first pressure regulating valve, a liquid level meter, a three-way valve, a first control valve, a temperature regulator, a thermometer, an oxygen/carbon dioxide measuring instrument, a PH measuring instrument, a nutritional ingredient measuring instrument, a second control valve, a second peristaltic pump, a third peristaltic pump, a urea/uric acid/inorganic salt measuring instrument, a fourth peristaltic pump, a third control valve, a second fluid pressure gauge,a second pressure regulating valve, a fourth control valve, a fifth control valve, a fifth peristaltic pump, a sixth control valve, a gas permeable membrane, a dialysis membrane, a central control platform, a cloud data center and an electromagnetic field. According to the three-dimensional simulation culture system for the stem cells, the stem cells with higher quality and quantity can be cultured, the stability is good, and the treatment effect of the stem cells is improved.

The invention discloses a caproic acid fermented strain and a caproic acid extracting method. The caproic acid fermented strain is js-22-03, js-22-07 and js-22-12. Bred bacterial strains are good in passage stability, and the yield of the bred bacterial strains is increased to 1.90 g/100 mL from 1.20 g/100 mL compared with an original bacterial strain. The high-yield bacterial strains js-22-03, js-22-07 and js-22-12 are obtained through culture and screening, and the advantages of being short in fermentation time, stable in genetic property, high in yield and the like are achieved. The fermentation time is shortened to be within 10 days, and the caproic acid yield is increased to 1.90 g/100 mL from original 1.20 g/100 mL.

The invention discloses a recombinant plasmid for genetic transformation of pleurotus eryngii and application thereof and provides a DNA (Deoxyribonucleic Acid) segment and the recombinant plasmid containing the DNA segment, wherein the DNA segment sequentially comprises a promotor shown as a sequence 1 and a terminator shown as a sequence 2 from upstream to downstream. According to a method for genetic transformation of the pleurotus eryngii, which is established by the invention, the foundation for theoretical basis and technical support for fundamental research and molecular breeding of the growth and development mechanism of the pleurotus eryngii is laid, the storage for developing a novel bioreactor is provided and wide application field for developing and utilizing pleurotus eryngiiresources and bioactive substances thereof is opened up.

The invention provides an L-homoserine production bacterial strain. The L-homoserine production bacterial strain is characterized by containing a single and stable chromosome and not containing DNA carrier plasmids or other free DNA carriers, one or more genes related to L-threonine synthesis on the chromosome DNA of the bacterial strain are subjected to knockout or weakening, and/or the genes aresubjected to mutation for enhancement, and/or one or more genes related to the L-homoserine metabolic pathway are integrated and copied on the chromosome DNA of the bacterial strain.

The invention provides lactobacillus paracasei SLP16 for producing polysaccharides, application of the lactobacillus paracasei SLP16 and a feed additive prepared from the lactobacillus paracasei SLP16, and relates to the technical field of feed additives. The lactobacillus paracasei SLP16 disclosed by the invention is Lactobacillus paracasei SLP16; the Latin name is Lactobacillus paracasei, the name of the preservation unit is Guangdong Microbial Culture Collection Center; the address is Floor 5, Building 59, No. 100 courtyard, Xianlie Middle Road, Guangzhou city; the preservation date is July 5, 2021; and the preservation number is GDMCCNo: 61769. The SLP16 disclosed by the invention is still stable after passage, can inhibit escherichia coli and staphylococcus aureus, has good cholate-resistant and acid-resistant effects, has cohesiveness, hydrophobicity and oxidation resistance, and also can generate exopolysaccharides.

The invention relates to 'a subcloned cell strain TF-1-A2, a preparation method thereof and application' and belongs to the technical field of biology. The preparation method of the stable subcloned cell strain TF-1-A2 includes the steps: domesticating GM-CSF (granulocyte-macrophage colony-stimulating factor) dependent TF-1 cells into NGF (nerve growth factor) dependent strains; cloning the induced NGF dependent TF-1 cells by the aid of methylcellulose semisolid media; picking monoclonal cells from the semisolid media and enlarging and cultivating the monoclonal cells; and preparing a dose-effect curve of each monoclonal cell strain to the NGF and performing screening to obtain the subcloned cell strain TF-1-A2. The subcloned cell strain TF-1-A2 obtained by the preparation method is highly sensitive to the NGF and has fine reactivity and continuous inheritance stability. A TF-1 cell growth method established by the aid of the subcloned cell strain TF-1-A2 is used for externally and quantitatively measuring biological activity of the nerve growth factor, and is high in signal-to-noise ratio, fine in repeatability and superior to an existing method.

The invention discloses an aspergillus niger strain and application thereof in ochratoxin A degradation, and belongs to the field of gene engineering. The invention provides the Aspergillus niger FS-UV-21 strain which is preserved in the China General Microbiological Culture Collection Center on November 9, 2020, and the preservation number of the Aspergillus niger FS-UV-21 strain is CGMCC No. 20751. The aspergillus niger FS-UV-21 has a good degradation effect on ochratoxin A, the degradation rate reaches 74.49%, and the degradation rate is improved by 18.23% compared with that of an original strain; the time for achieving the optimal degradation effect is advanced and is shortened by 18 hours; aspergillus niger belongs to food-grade microorganisms, has relatively high food safety, and can realize efficient biological degradation of fungaltoxin.

The invention discloses a high-yielding penicillin strain, a screening method of the strain, and application of the strain in penicillin production, and belongs to the technical field of antibiotics production and application. The strain is characterized in that penicillin fermenting unit is increased by 13.2%, so that the yield of penicillin is effectively increased, and the production cost is decreased. The screening method comprises the following steps: (A) preparing a protoplast; (B) performing high-energy electronic mutagenesis; (C) rationally screening; and (D) screening with a shake bottle. The penicillin strain screening method is high in purposiveness, and high in mutation probability.

The invention discloses a strain capable of highly producing vitamin K2 (MK-7), a screening method of the strain and a method for producing the vitamin K2 (MK-7) by using the strain, and belongs to the field of microbial fermentation. The strain is preserved in China Center for Type Culture Collection on August 23, 2021, and the preservation number is CCTCC M20211066. Mutagenesis is performed by using nitrosoguanidine, and the strain is obtained through shake flask screening, and has the characteristics of high shake flask titer, good passage stability and the like. When the strain is used for fermentation, a fermentation unit can reach 240 mg/L or above in cooperation with an optimal fermentation culture medium and a control process, the fermentation unit is improved by 243% compared with that of an original strain, the yield of the vitamin K2 (MK-7) can be effectively increased, the cost of raw materials, water, electricity, steam and the like for fermentation is obviously reduced, pollution emission of the unit yield is reduced, and the strain has high economic benefits.

The invention discloses a cell line for detecting the activity of human interferon-kappa and a construction and detection method thereof. The cell line is obtained by transfecting eukaryotic cells with ISRE (interferon-sensitive response element) luciferase reporter genes and stably screening monoclonal cell lines. The cell line constructed by the invention is easy to culture and amplify and good in passage stability, and has the advantages of high sensitivity, short detection time, completion within 4-6 hours, and capability of greatly improving the activity release efficiency of the human interferon-kappa in the production process.

The invention discloses bacillus with relatively high tolerance to methanol and belongs to the technical fields of microbial culture, molecular biology and application. The strain disclosed by the invention has been preserved in the China Center for Type Culture Collection on April 6, 2021, and the preservation number is CCTCC NO: M 2021326. The strain can tolerate 20% or even higher methanol, has good passage stability, still keeps methanol tolerance after 50 generations of passage, can be applied to construction of methylotrophication strains and synthesis of high-added-value products by using methanol as a substrate, and has wide industrial application prospects.

The present invention provides a kind of penicillin V potassium high-yielding bacterium and its application in fermentative production of penicillin V potassium, the penicillin V potassium high-yielding bacterium is Penicillium chrysogenum ( Penicillium Chrysogenum ) B181126 strain, the preservation date is October 14, 2019, the preservation number is CCTCC NO: M2019823, and the preservation unit is the China Center for Type Culture Collection (CCTCC). When Penicillium chrysogenum B181126 is used in production, with the optimal fermentation process, its fermentation unit can reach more than 80,000 U/mL, which is 36.4% higher than the starting strain, and the fermentation unit of penicillin V potassium is greatly increased. At the same time, 4 ‑ Hydroxypenicillin V potassium impurity content is less than 1.2%.