69 results about "Kluyveromyces sp." patented technology

The invention provides a kluyveromyces marxianus engineering bacterium obtained from recombinant expression of porcine circovirus type II capsid protein; and porcine circovirus type II virus-like particles are obtained by cloning porcine circovirus type II capsid protein genes into an expression vector and conducting recombinant expression in kluyveromyces marxianus. The invention also provides a preparation method of a porcine circovirus type II virus-like particle vaccine, wherein the preparation method comprises the following steps: preparing the porcine circovirus type II virus-like particles through high-density fermentation of the recombinant kluyveromyces marxianus, and then conducting separation and purification so as to prepare the vaccine. The porcine circovirus type II virus-like particle vaccine provided by the invention, which can generate a high-level serum IgG antibody just by implementing injection immunization once, has the advantages of being good in immunizing effect, high in safety, simple in culture operation, high in yield, low in production cost and the like, and the porcine circovirus type II virus-like particle vaccine can achieve large-scale enlarged production; and the porcine circovirus type II virus-like particle vaccine can be used for relieving and preventing related clinical symptoms caused by the infection of porcine circovirus type II (PCV2).

The invention relates to a method for preparing cholesterol reducing eggnog fermenting drink by utilizing lactobacillus and microzyme which produce bile salt hydrolase, belonging to a functional drinkwhich is prepared from the following ingredients: 15% of whole egg pulp, 35% of milk, 7% of saccharose, 0.3% of CMC-Na. and 0.2% of carrageenin, wherein the ratio of the raw materials (the whole eggplug and the milk) to water is 1:1 (W/V). The primary fermentation condition is described as following: streptococcus thermophilus Tx, Lactococcus lactis subsp.lactis KS4 and Lactobacillus casei KL1 are mixed in proportion of 1:1:1, the inoculum size is 3%, and then the mixture is fermented for 8h at the temperature of 43 DEG C. The secondary fermentation condition is described as following: Kluyveromyces marxianus M3 and K1 are compounded in proportion of 1:1 or the inoculum size of the single strain is 1%, and then the composite is fermented for 24-26 h at the temperature of 30 DEG C (mixture strain) or 32-34 DEG C; after ripening is carried out for 1 day at the temperature of 4 DEG C, the reducing rate of raw material cholesterol reaches as high as 89.3%. By utilizing the characteristics of strain high-yielding BSH, exopolysaccharide and the like, the invention has the efficiencies of immunological regulation, cholesterol reducing, tumor prevention and the like, and the problem of egg smell is not only solved, but also the content of raw material cholesterol is efficiently reduced through egg pulp proper sterilization and eggnog secondary fermentation. The eggnog drink preparedby the invention has simple fermentation process, short period and lower cost and is suitable for industrialized production.

The invention belongs to the technical field of biological medicine, and concretely relates to a swine fever virus subunit vaccine and a preparation method and a purpose thereof. The invention provides a kluyveromyces marxianus yeast recombination strain used for preparing the swine fever virus subunit vaccine. The recombination strain is constructed by the following steps: swine fever virus envelope protein E2 is intercepted, through codon optimization, a coding sequence of the swine fever virus mE2 protein is obtained, and then is cloned to a kluyveromyces marxianus yeast expression vector,and the kluyveromyces marxianus yeast host strain is transformed. The invention also provides the method for preparing the swine fever virus subunit vaccine, which comprises the following steps: the kluyveromyces marxianus yeast host strain is subjected to recombination expression by using mE2, steps of culture, centrifugation, cell disruption, and separating purifying are carried out to obtain the swine fever virus mE2 protein antigen, and the purified antigen and an adjuvant are subjected to complex formulation to prepare the swine fever virus subunit vaccine. The injection immunotherapy ofswine fever virus mE2 protein recombination subunit vaccine can obtain a protective IgG antibody, and the subunit vaccine can reduce and prevent the swine fever virus infection-related disease.

The fusion protein may be expressed from a polynucleotide having a promoter element and/or a transcription termination sequence, in each case operatively associated with a polynucleotide encoding the fusion protein. The yeast may be S. cerevisiae, S. pombe, Pichia (Hansenula) sp. or Kluyveromyces sp.

The invention discloses a recombinant yeast Kluyveromyces for expressing antibodies or antibody analogues and application thereof. The invention provides a method for constructing the recombinant yeast Kluyveromyces for expressign antibodies or antibody analogues. The method comprises the following steps: encoding genes of the antibodies or the antibody analogues are guided into the yeast Kluyveromyces to obtain recombinant bacteria; the antibody analogues are fusion proteins formed by Fc fragments of the antibodies and proteins or protein subunits; the encoding genes of the antibodies are heavy chain and light chain encoding genes of the antibodies. The recombinant yeast Kluyveromyces for expressing antibodies or antibody analogues can be cultured to produce complete antibodies or antibody analogues. The invention uses the yeast Kluyveromyces to prepare the antibodies or antibody analogues to preliminarily overcome the difficulties of difficult antibody production, high purity and large quantity requirements for products and provide good application prospects.

The invention belongs to the technical field of aquaculture, and particularly relates to a special-purpose immunopotentiating agent for Cynoglossus semilaevis Gunther. The special-purpose immunopotentiating agent for the Cynoglossus semilaevis Gunther is formed by mixing the following main components in parts by weight: 0.2-0.4 part of beta-glucan, 4-12 parts of acanthopanax roots, 5-10 parts of ampelopsis grossedentata, 10-15 parts of lepidium meyenii, 12-15 parts of kluyveromyces fragilis, 10-20 parts of eucommia ulmoides leaves, 5-10 parts of malt, and 65-80 parts of bamboo vinegar. The abuse of antibiotics cannot be ignored in the industry of the aquaculture. The special-purpose immunopotentiating agent for the Cynoglossus semilaevis Gunther, disclosed by the invention, uses purely natural plant ingredients, and a small amount of beta-glucan is added, so that the immunopotentiation effect of a composition can be effectively enhanced; and in addition, the components do not contain the antibiotics, so that a series of consequences caused by the abuse of the antibiotics are avoided.

The invention discloses a method for fermenting Anfu ham by utilizing a compound micro-ecological fermenting agent and belongs to the field of food fermentation. The method for fermenting Anfu ham by utilizing the compound micro-ecological fermenting agent comprises the following steps: pre-treating, salting, dehydrating, firstly fermenting and secondly fermenting. The bacterial strains in the compound micro-ecological fermenting agent include lactobacillus pentosus, lactobacillus plantarum, kluyveromyces lactis and issatchenkia orientalis, wherein the number ratio of lactobacillus pentosus to lactobacillus plantarum to kluyveromyces lactis to issatchenkia orientalis is 1:(1-3): (1-3):(1-5) and the total amount of viable bacteria of the compound micro-ecological fermenting agent is 3*106-8*10<6>cfu/mL. According to the method for fermenting Anfu ham by utilizing the compound micro-ecological fermenting agent disclosed by the invention, the ham having characteristics of short production period, natural product color, high yield, various flavors and the like can be prepared in the manner of adding the compound micro-ecological fermenting agent and the compound seasoning into the ham meat.

The invention provides a Kluyveromyces marxianus recombinant strain capable of being used for preparing feruloyl esterase AnfaeA. The recombinant strain is constructed by cloning an aspergillus nigerferuloyl esterase AnfaeA gene with an optimized sequence to an expression vector and converting a Kluyveromyces marxianus host strain, and the yield of the feruloyl esterase obtained by high-density fermentation of the recombinant strain reaches 120000 U/ml. The invention also provides a method for preparing ferulic acid by hydrolyzing corncob powder with the feruloyl esterase. The feruloyl esterase AnfaeA prepared from the recombinant strain and xylanase have a synergistic effect, so that the corncob powder can be efficiently hydrolyzed to obtain the ferulic acid. The feruloyl esterase provided by the invention can be used for preparing phenolic substances such as ferulic acid, p-coumaric acid and the like through biodegradation of agricultural byproducts such as corncobs, rice bran, cornbran and the like, so that the feruloyl esterase has a wide application value in the fields of foods, papermaking, feeds, medicines and the like. Meanwhile, the preparation method is simple in process, high in yield and very suitable for large-scale production.

The invention discloses construction and application of heat-resistant yeast engineering bacteria capable of producing glycerine under high temperature aerobiotic condition. A heat-resistant kluyveromyces marxianus is used as a platform, methods of genetic engineering, metabolic engineering and the like are utilized, a strain having triose phosphate isomerase (TPI1) deletion is constructed, and the constructed strain has the capacity of efficiently producing the glycerine through efficient utilization of glucose, levulose and xylose under the high temperature aerobiotic condition. The obtainedkluyveromyces marxianus strain YZB115 produces 40.32 g/L glycerine through 80g/L glucose, produces 41.84 g/L glycerine through 80g/L levulose and 18.64g/L glycerine through 80g/L xylose under the aerobiotic condition of 42 DEG C, the production rates are respectively 0.84g/L/h, 0.50g/L/h and 0.22g/L/h, the yields are respectively 0.50g/g, 0.50g/g and 0.23g/g, in the fermentation process of the constructed engineering strain, a by-product namely ethanol is not produced, and xylitol is not accumulated when the operation of producing the glycerine through fermentation of xylose is ended.

The invention discloses a heat-resistant yeast engineering strain producing xylitol under a high-temperature aerobic condition and a construction method and application thereof. The heat-resistant yeast engineering strain is a heat-resistant yeast engineering strain YZB194, and the classification name of the strain is Kluyveromyces marxianus, the strain is collected in the China General Microbiological Culture Collection Center (CGMCC) in No.3 Yard 1, Beichen West Road, Chaoyang District, Beijing on November 25, 2019 with the collection number of CGMCCC NO.19004. YZB194 synthesizes 203g/L xylitol by using 121 g/L glucose and 205 g/L xylose by batched supplement fermenyation with a fermentation tank under the aerobic condition of 42 DEG C, the synthesis rate of xylitol is 2.99g/L/h, and theconversion rate of xylitol reaches 99% of the maximum theoretical value.

The invention discloses a low-yield n-propanol yeast, which is classified and named as Kluyveromyces marxianus Y245, is preserved in the China Center for Type Culture Collection on March 15, 2021, and has the preservation number of CCTCC NO: M2021225. The yeast is applied to production of fen-flavor Xiaoqu raw wine, the content of n-propanol in a wine body is reduced by 39.85% compared with that of a production control group, and the produced Xiaoqu raw wine is pure in fen-flavor, refreshing and clean in mouth, harmonious in fragrance and typical in style.

The invention provides a method for constructing a multi-copy kluyveromyces lactis expression vector efficiently in an in-vitro manner. The method comprises the following steps: 1) 10 primers for PCR are designed and synthesized according to the gene sequence of a carrier pKLAC2 of kluyveromyces lactis GG799; 2), synthesizing the gene segments of yeast expression nuclear structures of four restriction enzyme loci; 3) constructing the expression vector BpKLAC2; 4) using the restriction enzyme loci to verify the accuracy of the expression vector through digestion; 5) inserting a target gene in the expression vector BpKLAC2 to become the single-copy expression vector containing the target gene; and 6) applying the biological bricking method to achieve the in-vitro multi-copy of the expression vector. Through the application of the method, the expression quantity and the stability of the target protein gene of the kluyveromyces lactis can be improved.

The invention belongs to the technical field of fermentation, and particularly relates to a preparation method of an apple-flavor yeast culture and application of the yeast culture. The preparation method of the yeast culture comprises the following steps: (1) mixing and crushing soybean meal and corn bran to serve as a base material for later use; (2) preparing kluyveromyces marxianus fermentation liquor; (3) supplementing the mannobiose trisaccharide hydrolysate into the kluyveromyces marxianus fermentation liquor, uniformly mixing, and inoculating into the base material; and (4) carrying out aerobic shallow fermentation on the inoculated base material to obtain the yeast culture after the fermentation is finished. According to the invention, Kluyveromyces marxianus is used as a fermentation strain for solid-state fermentation, and the mannobiose trisaccharide hydrolysate is used as a carbon source, so that the prepared yeast culture has high viable count, and a wet material after fermentation has apple fragrance and better phagostimulant property; the saccharomyces cerevisiae solves the problem that the traditional saccharomyces cerevisiae produces strong wine flavor after fermentation and affects the animal intake, and can significantly improve the feed intake and daily gain as an animal feed additive.

The invention belongs to the technical field of preparation of tobacco flavors, and provides a preparation method of a fermented plum refined extract. The preparation method comprises the following steps: inoculating Debaryomyces hansenii and Kluyveromyces marxianus into plum slurry according to a mass ratio of 1: (2-3), fermenting, and extracting the obtained fermented product to obtain the fermented plum refined extract. According to the technical scheme, the problems that plums are poor in extraction effect, light and rough in fragrance and poor in sensory effect when applied to tobacco shreds in the prior art are solved.

The invention belongs to the technical field of bioengineering, and particularly provides a safe and efficient Kluyveromyces marxianus high-density fermentation medium and a use method thereof, optimal fermentation conditions are obtained by optimizing a fermentation process, and by adopting the method provided by the invention, the fermentation efficiency is improved, and the fermentation cost is reduced. The feeding speed is adjusted, so that the viable count of the Kluyveromyces marxianus fermentation tank can be remarkably increased, the concentration of bacteria in the final fermentation liquid in the tank can reach about 1.2 * 10 < 10 > cfu/mL, the problem that the viable count of the yeast in the fermentation liquid in the tank is generally low in the existing Kluyveromyces marxianus fermentation process is solved, and high-quality industrial production conversion is realized.

The invention belongs to the technical field of microorganisms, and particularly relates to Kluyveromyces. The Kluyveromyces is Kluyveromyces siamensis THUZTY2041, the preservation date is October 19, 2020, the preservation unit is China General Microbiological Culture Collection Center (CGMCC), the preservation address is institute of microbiology, Chinese Academy of Sciences, 3#, 1# yard, West Beichen road, Chaoyang District, Beijing, and the preservation number is CGMCC NO. 20917. The invention further provides application of the Kluyveromyces in production of xylitol. Straw sugar fermentation tail liquid is used as a raw material, the Kluyveromyces can be cultured at high temperature to obtain the xylitol under the condition of low cost, the condition constraint of traditional industrial production is eliminated, the advantages of high-temperature fermentation production are exerted, and the comprehensive utilization value of agricultural straw is improved.

The invention relates to a method for preparing high-purity galactooligosaccharide by beta-galactosidase. The method comprises the following steps: (1) preparing galactooligosaccharide (GOS) by usingfree beta-galactosidase to catalyze lactose through a transglycosylation reaction; (2) performing whole-cell fermenting preparation with Kluyveromyces lactis; and (3) obtaining the high-purity galactooligosaccharide by whole-cell purification with the Kluyveromyces lactis. After a GOS synthesis is carried out for 2 hours, the GOS yield is 22.78%, and after whole-cell treatment with Kluyveromyces lactis is carried out for 15 hours, the purity of GOS is over 90%. The process provides a simple, efficient and inexpensive method for production of high-purity oligosaccharides. The GOS produced by the method is high in purity, low in production process cost and high in efficiency, is green and environmentally friendly, and is expected to be widely applied.

The invention belongs to the technical field of microorganisms, and particularly relates to a Lachancea thermotolerans strain and application thereof. The preservation number of the Saccharomyces cevevisiae strain is CGMCC (China General Microbiological Culture Collection Center) No.21713 or CGMCC No.21714, and the classification name is Lachancea thermotolerans. Experimental results show that the strain has the capacity of stably producing lactic acid at high yield under different fermentation substrates and improving the volatile aroma of grape wine. In the process of brewing dry red wine and rose wine, the yeast strain and Saccharomyces cevevisiae are mixed and fermented, so that the acidity of the wine can be increased, the pH of a wine sample can be reduced, the glycerol content of the wine can be increased, the contents of ethyl lactate, ethyl butyrate and phenethyl alcohol can be increased, the wine is endowed with more flower fragrance, and the complexity of the fragrance of the wine can be increased. The yeast strain provided by the invention is strong in fermentation capability and excellent in fermentation performance, and has an important value in the application of improving the acidity and quality of the wine.