52results about How to "Improve freeze-drying survival rate" patented technology

The invention relates to a lyophilization process of lactobacillus plantarum, and belongs to a microbial agent preparation process. In the lyophilization process of lactobacillus plantarum, the process parameters are that the pH of a lyophilization protective agent is 7.0-7.5, the balancing time of bacterium mire and the protective agent is 20-40minutes, pre-lyophilization is carried out for 2.0-2.5h under the condition of minus 80 DEG C, a phosphate buffer is adopted to prepare the protective agent, lyophilization livability can be up to over 90%, and the viable count can be up to over 4.0*1010cfu/g. Compared with the general method, the method disclosed by the invention has the advantages that the livability of the lactobacillus plantarum is improved remarkably.

The invention provides a composite protective agent for increasing the freeze-drying survival rate of lactobacillus plantarum and a preparation method thereof. The protective agent is prepared from soybean polysaccharide, galactose, fructo-oligosaccharide, trehalose, skimmed milk, proline and distilled water. The preparation method includes the steps that the distilled water is divided into three parts, and soybean polysaccharide, galactose, fructo-oligosaccharide and trehalose are added to one part for dissolution and sterilization; the skimmed milk is added to another part of the distilled water for dissolution, and a skimmed milk solution is obtained and sterilized; proline is dissolved in the remaining distilled water, and membrane filtration sterilization is conducted; the three prepared solutions are evenly mixed under the sterile condition, and then the composite freeze-drying protective agent is obtained. According to the freeze-drying protective agent for lactobacillus plantarum, a freeze-drying protective additive is added in the fungus powder preparation process, the anti-freezing capacity of fungi can be improved, and therefore the freeze-drying survival rate of the fungus powder is increased, the storage period is long, and the survival rate is not likely to be reduced. The freeze-drying survival rate of the prepared fungus powder of lactobacillus plantarum ranges from 82.73% to 93.26%, and the viable count of the fungus powder ranges from 1.14*10<11> cfu/g to 1.98*10<11> cfu/g.

The invention relates to a preparation method of a freeze-dried powder preparation of Lactobacillus acidophilus, Lactobacillus paracasei or lactobacillus rhamnosus, and provides a culture medium used in the freeze-drying process of Lactobacillus acidophilus, Lactobacillus paracasei or lactobacillus rhamnosus products. The inventor combines two critical factors influencing bacterial fermentation together, and creatively carries out fermentation in a high-density fermentation process by means of combination of two-sectional pH and three-sectional temperature variation, so that the relatively single form of the maximum cell biomass and the highest fermentation activity is improved remarkably, meanwhile, the obtained freeze-dried preparation is high in viable count and excellent in stability. The invention also provides an excellent freeze-drying protective additive.

The invention discloses selenium-enriched bacillus bifidus micro-capsules. The selenium-enriched bacillus bifidus micro-capsules are prepared by adopting a method comprising the following steps: uniformly mixing a sodium alginate solution with selenium-enriched bacillus bifidus thallus and calcium carbonate powder so as to obtain a mixture; dropwise adding the mixture into vegetable oil containingan emulsifier, and carrying out stirring so as to obtain an emulsion; sequentially adding vegetable oil containing glacial acetic acid and an emulsifier solution into the emulsion, carrying out stirring, and allowing standing; and then, separating oil phase so as to obtain aqueous phase, and centrifuging the aqueous phase so as to obtain the selenium-enriched bacillus bifidus micro-capsules. By screening reagents, materials and dosage ratio adopted in micro-capsule preparing, coating and freeze-drying processes, embedding rate of the selenium-enriched bacillus bifidus micro-capsules disclosedby the invention are improved. The embedding rate of the selenium-enriched bacillus bifidus micro-capsules is up to 98% while the particle size is smaller than 200 microns and the freeze-drying survival rate is up to 85%. According to normal-temperature stability results, viable number of the selenium-enriched bacillus bifidus micro-capsules is still about 10<8> cfu/g within 180 days.

The invention aims to provide a method for improving the freeze-drying survival rate of Lactobacillus acidophilus. The method comprises the following steps of: culturing the Lactobacillus acidophilus for 18h at the temperature of 37 DEG C, performing sublethal treatment on the Lactobacillus acidophilus, centrifuging for 10 to 15min at the temperature of 4 DEG C at the rotating speed of 7,000rpm, adding skimmed milk and a phosphate buffer solution into bacterial sludge of the Lactobacillus acidophilus, pre-freezing for 8 to 12h at the temperature of -40 DEG C, and putting into a freeze dryer and freeze-drying for 18 to 24h at the temperature of between -50 and -60 DEG C under the vacuum degree of between 4 and 6Pa to obtain bacterial powder of the Lactobacillus acidophilus. In the method for improving the freeze-drying survival rate of the Lactobacillus acidophilus, a Lactobacillus acidophilus culture solution is subjected to cold shock, heat shock or acid shock treatment first so as to ensure that the Lactobacillus acidophilus induces to synthesize cold shock protein and heat shock protein under adverse circumstances or changes the composition of fatty acid of cell membranes, so that the resistance of the Lactobacillus acidophilus in the subsequent freeze-drying process is improved, and the freeze-drying survival rate and the viable count of the bacterial powder are improved.

The invention provides a preparation method of a powdery bdellovibrio bacteriovorus lyophilized preparation with high survival rate. The method comprises the steps of obtaining a bacteria solution or a bdellovibrio bacteriovorus bacterial suspension from which a harmful host is separated according to a conventional culture method of bdellovibrio bacteriovorus; preparing a protective agent solution; carrying out freeze drying on a to-be-lyophilized mixed solution, repeatedly vacuumizing and filling an inert gas to finally prepare the preparation into powder; and carrying out sealing packaging on the bdellovibrio bacteriovorus lyophilized preparation under a vacuum condition or under the condition of filling the inert gas to prepare a finished product, namely the bdellovibrio bacteriovorus lyophilized preparation. Through compounding of multiple lyophilized protective agents, the freeze-drying survival rate of bdellovibrio bacteriovorus is improved, the character of the bdellovibrio bacteriovorus lyophilized preparation is powder, and dispersion and compounding of the lyophilized preparation are facilitated.

The invention discloses a streptococcus thermophilus freeze-drying protective agent and a preparation method thereof. The streptococcus thermophilus freeze-drying protective agent comprises the following components in parts by mass: 10-20 parts of dried skim milk, 3-10 parts of raffinose, 4-10 parts of soybean oligosaccharides, 1.05-5.0 parts of dextran D40, 0.3-0.8 parts of sodium tripolyphosphate, 0.005-0.02 parts of propylgallate and 100 parts of distilled water, wherein the soybean oligosaccharides and the dextran D40 can both be purchased from LUOSHENBO science and technology Ltd.. The anti-freezing ability of thallus can be increased by adding a freeze-drying protective agent during a thallus powder preparing process, thus the freeze-drying survival rate of the thallus powder can be increased, the storage period can be longer, and the survival rate can not be easily lowered.

The invention provides a lactobacillus acidophilus anti-freeze culture medium and an application method thereof. The culture medium includes the following components by weight: 16-20 g of glucose, 0.4-0.8 g of fructus tribuli polysaccharide, 3-5 g of yeast extract, 4-6 g of sodium chloride, 0.3-0.5 g of mannitol, 0.8-1.2 g of sodium glutamate, 8-12 g of soybean peptone, 0.5-2.0 g of diammonium hydrogen citrate, 0.2-0.5 g of betaine, 1.0-2.5 g of dipotassium phosphate, 0.1-0.2 g of MgSO4, 0.5-1.0 ml of Tween-80 and 1,000 ml of distilled water. The culture medium has the advantages that: after lactobacillus acidophilus is cultured by using the anti-freeze culture medium, the freeze-dry survival rate of the lactobacillus acidophilus can reach up to 79.54 percent, and viable count of fungal powder reaches up to 4.09*10<11> cfu/g; and the lactobacillus acidophilus MRS (de Man, Rogosa and Sharp) broth is used for culture, so that the freeze-dry survival rate of the prepared fungal powder isonly 49.72 percent, and the viable count is only 1.24*10<11> cfu/g.

The invention belongs to the technical field of microorganism application, particularly relates to bifidobacterium longum SYSU-02 and application thereof, and discloses the bifidobacterium longum SYSU-02 with the preservation number of CGMCC (China General Microbiological Culture Collection Center) No.20651. The invention further discloses a preparation method of the bifidobacterium longum SYSU-02. An inhibition zone experiment and an MIC experiment show that the strain has an inhibition effect on pathogenic staphylococcus epidermidis and pseudomonas aeruginosa, and can be added into nasal cavity, oral cavity or skin cleaning products. Animal experiments prove that the strain can relieve the severity of acute ulcerative colitis and has a good protection effect on intestinal tracts. Meanwhile, the bifidobacterium longum-chitosan-inulin-calcium alginate microcapsule is constructed by adopting a microencapsulation technology and a freeze-drying technology, so that the stress resistance and the room-temperature storage stability of the strain are also improved on the basis of maintaining a relatively high freeze-drying survival rate; therefore, the survival rate of the bifidobacterium longum in the production, transportation and storage processes is ensured.

The invention provides a culture medium for improving the freezing tolerance of Lactobacillus bulgaricus and application of the culture medium. The culture medium contains the following components byweight: 12g-30g of mannose, 5g-10g of mycose, 3g-6g of casein peptone, 3g-6g of anhydrous sodium acetate, 5g-10g of beef extract powder, 3g-6g of potassium acetate, 1.5g-4.0g of anhydrous calcium chloride, 0.1g-0.8g of magnesium sulfate, 0.1g-0.5g of manganese sulfate, 0.1g-1g of L-cysteine hydrochloride, 0.6mL-1.2mL of Tween-80 and 1000mL of distilled water. By utilizing the freezing-resistant culture medium and particularly a freeze-drying protection method provided by the invention, relatively high freeze-drying survival rate of Lactobacillus bulgaricus can be realized, the preservation period is relatively long, and the survival rate is unlikely to be decreased.

The invention relates to a method for improving lyophilized activity of Oenococcus oeni by utilizing stress pretreatment, which comprises the following steps: performing enrichment culture of Oenococcus oeni strain to reach the stable period, centrifugally collecting the bacterial sludge, resuspending in the culture medium ATB containing the stress treatment fluid, standing at 25 DEG C for 2-3h, centrifuging, harvesting bacterial body, adding proper sodium pyruvate solution with mass concentration of 2-5% as the lyophilized protective agent and performing freeze drying to obtain lyophilized bacteria powder. The lyophilized bacteria powder prepared by the method of the invention can be used as direct Oenococcus oeni fermentation starter. The method of the invention introduces the idea of stress pretreatment, and uses sodium pyruvate as the lyophilized protective agent, which is the main component of the monosodium glutamate and is safe and no harm to human and poultry and has various health-care effects, the introduced idea can be used in the production process of direct edible fermentation starter.

The invention discloses an overexpressed UGPase (UDP-glucose pyrophosphorylase) gene and a method for constructing recombinant lactobacillus acidophilus thereof. The method is characterized by comprising the specific steps as follows: (1) a UGPase gene LBA0625 is amplified with lactobacillus acidophilus genome DNA as a template; an expression vector pMG36e is subjected to single restriction digest with restriction enzyme Hind III, and after dephosphorylation and gel recovery are performed, a recombinant expression vector is constructed by inserting a PCR amplification product into the expression vector pMG36e; (2) an overexpression plasmid subjected to extraction and concentration is imported into lactobacillus acidophilus through electrotransformation, the lactobacillus acidophilus is resuscitated at 37 DEG C for 2 h, applied to an erythrocin resistant plate and cultured at 37 DEG C for 36 h for screening transformants; the transformants are subjected to PCR verification, and the recombinant lactobacillus acidophilus PLY127-1 of the overexpressed UGPase gene is obtained. The freeze-drying survival rate of the lactobacillus acidophilus can be increased substantially.

The invention provides a swine pasteurellosis vaccine enrichment medium, and relates to the field of biology. The swine pasteurellosis vaccine enrichment medium is prepared from the following raw materials by weight: 20.0g of meat liver and stomach membrane digestive juice powder, 8.0g of bovine pancreas digestive juice, 10.0g of peptone, 5.0g of NaCl, 1.0g of a growth promoting factor, and purified water added to 1000ml. A preparation method of the swine pasteurellosis vaccine enrichment medium comprises the following steps: adding all the raw materials for preparing the swine pasteurellosisvaccine enrichment medium into purified water, fully dissolving the raw materials, and carrying out sterilization at 121 DEG C for 15 minutes for later use. The invention relates to an application ofa synthetic dry powder culture medium in swine pasteurellosis vaccine production. The synthetic dry powder culture medium has the beneficial effects that commercial raw materials can be selected, theculture medium is clear, the number of cultured bacteria is high, and the freeze-drying survival rate of the bacteria is increased.

The invention discloses a freeze-drying protective agent and an application thereof to freeze-drying of bifidobacterium adolescentis, belongs to the technical field of microorganisms, and provides thefreeze-drying protective agent capable of obviously increasing the freeze-drying survival rate of the bifidobacterium adolescentis. The freeze-drying protective agent comprises the components of sorbitol, raffinose and whey protein; and when lyophilized powder of the bifidobacterium adolescentis is prepared by use of the freeze-drying protective agent, the freeze-dried survival rate of the bifidobacterium adolescentis is as high as 97.43 plus or minus 4.98%.

The invention relates to a novel thermophilic lactobacillus and the application thererof in the wet corn soaking process. The bacterial species preservation information of the thermophilic lactobacillus is as follows: name of preservation unit: Common Microbial Center of China Microbial Strain Collection Management Committee; Depository address: Institute of Microbiology, Chinese Academy of Sciences, No. 3 Academy, No. 1 Beichen West Road, Chaoyang District, Beijing; Date of deposit: 18 April 2018; Deposit No.: CGMCC No. 15623; Taxonomic name: Bacillus coagulans.