230 results about "Staphylococcus lactis" patented technology

The invention belongs to the field of fermentation, and particularly relates to a complex microbial inoculant, original cheese, processed cheese with a blood sugar reducing function and preparation and application of the complex microbial inoculant. Wherein the processed cheese is prepared by the method comprising the following steps: mixing the components including raw cheese, sugarcane juice, corn oil, casein, concentrated milk protein, blueberry powder, mono / diglycerol fatty acid ester, sodium citrate, sodium tripolyphosphate, sodium hexametaphosphate, salt guar gum, potassium sorbate and water, and then emulsifying to obtain the processed cheese, the sugar cane juice, the corn oil, the casein, the concentrated milk protein, the blueberry powder, the mono / diglycerol fatty acid ester, the sodium citrate, the sodium tripolyphosphate, the sodium hexametaphosphate, the salt guar gum, the potassium sorbate and the water, the original cheese is prepared from a complex microbial inoculant, and the complex microbial inoculant comprises lactococcus lactis bacterial powder, lactococcus lactis subsp. Lactis bacterial powder, lactobacillus delbrueckii subsp. Lactis bacterial powder, lactobacillus plantarum bacterial powder and lactobacillus paracasei bacterial powder. The processed cheese provided by the invention has a better function of controlling blood sugar, and meanwhile, the processed cheese is fine and uniform in texture and has good smearing performance.

The invention relates to the technical field of microorganisms, and particularly discloses a nitrogen-fixing and cadmium-reducing microbial agent as well as a preparation method and application thereof. The microbial agent consists of bacillus pseudomycoides, lactococcus lactis, azotobacter chroococcum and biochar, wherein the biochar is obtained by pyrolyzing and carbonizing rice straws. The bacillus pseudomycoides can reduce the bio-availability of soil cadmium; lactococcus lactis can secrete a large number of biological active substances such as exopolysaccharides and enzymes, and the activity of other microorganisms is stimulated and improved; azotobacter chroococcum converts nitrogen in air into ammonium, amino acid and peptide which can be utilized by plants and promotes plant growth, and released metallothionein contains free sulfydryl which is combined with Cd ions, so that a stable sulfide compound is formed. The biological carbon adsorbs and fixes the three bacteria, so that the microorganisms can continuously and effectively play a role and have a mutual synergistic effect, the fixation of Cd in the soil is further enhanced, the availability of nitrogen is improved, and the plant growth is effectively promoted.

The invention relates to the field of microorganisms, and discloses a Lactococcus lactis subsp. Lactis VB346 which is preserved in the China Center for Type Culture Collection on September 20, 2024, and the preservation number is CCTCC NO: M 20242013. The invention further discloses a preparation method of the Lactococcus lactis subsp. Lactis VB346. The lactococcus lactis subsp. Lactis VB346 disclosed by the invention has the capability of efficiently degrading purine nucleoside, and can decompose purine nucleoside in ingested food in intestinal tracts, so that the absorption amount of purine nucleoside by small intestines is reduced. The polypeptide has the ability of degrading bilirubin, and can be used for treating or improving hyperbilirubinemia, or improving liver and gall injury caused by hyperbilirubin; meanwhile, the acid resistance required by survival in the stomach, the cholate tolerance required by survival in the intestinal tract and the stable survival ability in the intestinal tract are achieved, and the bacillus subtilis has huge application prospects in preparation of drugs, microbial agents, health care products or food.

The invention belongs to the technical field of biological medicine, and discloses lactococcus lactis HX21473 and application thereof, the lactococcus lactis HX21473 is preserved in China General Microbiological Culture Collection Center (CGMCC) on January 20, 2025, and the preservation number is CGMCC NO.33476. The invention further discloses a preparation method of the lactococcus lactis HX21473. The invention provides a strain of lactococcus lactis HX21473 capable of efficiently expressing a foreign protein. The lactococcus lactis HX21473 has strong acid resistance, can be used as an oral vaccine live carrier, and promotes research, development and application of oral vaccines.

The invention belongs to the technical field of new energy materials, and particularly relates to a preparation method of a bamboo-based hard carbon sodium ion battery negative electrode material, which specifically comprises the following steps: (1) slicing, crushing, screening, sieving, drying and treating fresh bamboo under steam pressure to obtain bamboo powder; (2) bamboo powder and lactococcus lactis liquid are mixed and fermented, and after fermentation is completed, the bamboo powder and the lactococcus lactis liquid are washed to be neutral and dried; (3) placing the bamboo powder subjected to fermentation treatment in an inert atmosphere, heating, keeping constant temperature, and cooling to obtain a pre-carbonized sample; (4) soaking the pre-carbonized sample in a hydrochloric acid solution, continuously reacting, washing to be neutral, and drying; and (5) continuously heating the acid-washed and dried material in the step (4) in the inert atmosphere, carbonizing at a constant temperature, and cooling to obtain the final sodium-ion battery negative electrode material. The method disclosed by the invention has the advantages of remarkable environmental friendliness, low cost, simplicity and convenience in operation and the like; and the battery negative electrode material prepared by the method disclosed by the invention has excellent electrochemical performance.

The invention belongs to the technical field of aquaculture, and particularly relates to a pearl grouper fry rearing method. According to the method, firstly, after the roes are hatched, the fries are soaked with a bactericide, harmful bacteria on the surfaces of the roes and in a hatching pond can be effectively killed, and a bacteria solution of lactobacillus brevis serves as the bactericide, so that the use of antibiotics is reduced while the growth of pathogenic bacteria is inhibited; the culture pond is divided into 1m * 1m spaces by the partition plates, so that the phenomenon that the fries kill each other or snatch for food due to insufficient spaces is avoided, and uniform growth of the fries is facilitated; culture is carried out in stages according to nutritional requirements of different growth stages, and the Weissella microbial inoculum and the lactococcus lactis microbial inoculum are added to the feed in each stage, so that the intestinal microecological balance of the fry is adjusted, the growth and reproduction of harmful bacteria are inhibited, the intestinal digestion and absorption functions of the fry are enhanced, and the utilization rate of the feed is increased.

The invention belongs to the field of microorganisms, and particularly relates to lactococcus lactis Jlus 880314 and application thereof. The strain is classified and named as Lactococcus lactis, and is preserved in the China General Microbiological Culture Collection Center (CGMCC), and the preservation address is No.3, Yard 1, Beichen West Road, Chaoyang District, Beijing; the preservation number of the strain is CGMCC No. 33961. Time-of-flight mass spectrometry analysis shows that nisin exists in a metabolite of the strain, and the strain can be used for producing nisin. The compound shows an excellent and wide antibacterial function in antibacterial experiments, can be used for preparing antibacterial drugs, particularly has a remarkable inhibiting effect on growth of gram-negative bacteria and fungi, can be used for preparing drugs for relieving or treating enteritis, or preparing drugs, nourishment or health care products for regulating gastrointestinal tract micro-ecological balance of people or animals, and can be used for preparing medicines for relieving or treating enteritis. The compound can also be used for preparing antibacterial food additives and / or animal feed additives. A hemolysis experiment result shows that hemolysis is avoided, toxic and side effects are small, and wide development prospects and application values are achieved.

The invention discloses yoghurt oil with fruity flavor and a preparation method of the yoghurt oil, and belongs to the technical field of yoghurt oil processing. The Lactococcus lactis SITRS-0011 provided by the invention can be independently used as a leavening agent, when the Lactococcus lactis SITRS-0011 is used for fermenting yoghurt oil, the titration acidity can reach 83.21 DEG T, the yoghurt oil contains 2, 3-butanedione (1180 [mu] g / kg), acetoin (2092 [mu] g / kg), lactones (623 [mu] g / kg), 3-methylbutyraldehyde (117 [mu] g / kg), phenethyl alcohol (1863 [mu] g / kg), phenylacetaldehyde (336 [mu] g / kg) and other substances, and the Lactococcus lactis SITRS-0011 is rich in milk flavor, has flower fragrance and nut flavor, is unique in flavor, and can be used for preparing the and the overall sensory score is high.

The invention discloses a lactococcus lactis strain with high nisin yield and application, and belongs to the technical field of industrial microorganisms. According to the invention, a nisin-tolerant nisin high-producing strain (Lactococcus lactis MN6) is successfully bred on the basis of compound mutation of ethyl methane sulfonate and heavy ion beam and in combination with nisin resistance screening, the strain can tolerate a fermentation environment with the nisin concentration of 6000 IU. ML <-1 >, the nisin yield through shake flask horizontal fermentation can reach 10776 IU. ML <-1 >, which is 9.76 times of the shake flask fermentation yield of original bacteria, the strain has good passage stability, and the strain can be used for producing a high-yield strain of nisin. The method is more suitable for industrial production.

The invention relates to a polygonatum sibiricum probiotic compound preparation with an aging delaying effect and application thereof. The compound preparation comprises a polygonatum sibiricum extract and a probiotic composition, the bacterial strains in the probiotic composition comprise a combination of a bifidobacterium animalis subsp. Lactis BLa36 bacterial strain, a bifidobacterium longum BL21 bacterial strain, a bifidobacterium adolescentis BAC30 bacterial strain, a lactobacillus plantarum Lp90 bacterial strain, a lactobacillus casei LC89 bacterial strain, a bifidobacterium breve BBr60 bacterial strain and a pediococcus acidilactici CCFM7902 bacterial strain. After the rhizoma polygonati component and the probiotic component are combined for use, the rhizoma polygonati component and the probiotic component have potential synergistic effects in the aspects of improving the intestinal flora structure, regulating the intestinal environment, delaying senescence, reducing inflammation-related symptoms and the like. Moreover, further, various probiotic strains are compounded and combined for use, so that the capability of a related compound preparation in the aspect of delaying various symptoms of senescence can also be improved in a combined manner.

The invention discloses a lactococcus lactis recombinant bacterium for expressing cyclic diadenylate and application of the lactococcus lactis recombinant bacterium. Homologous DAC is introduced into lactococcus lactis NZ9000, PDE is knocked out to improve expression of cyclic diadenylate in lactic acid bacteria, and meanwhile, the yield of a cyclic diadenylate precursor ATP is increased by increasing the expression quantity of glycolysis key enzyme PFK; and the ldh gene is knocked out to reduce the accumulation of byproducts, so that the yield of the inner ring diadenylate of the lactic acid bacteria is further improved.

The invention provides a preparation method of a novel PEDV (porcine epidemic diarrhea virus) subunit vaccine, and belongs to the technical field of biology. The novel PEDV subunit vaccine is prepared by adopting a method comprising the following steps: (1) treating lactococcus lactis by using a high-pressure damp-heat method to obtain peptidoglycan particles; (2) treating the peptidoglycan particles by adopting an ultrahigh-pressure microjet technology to obtain a peptidoglycan carrier with the particle size of 280-850nm; and (3) mixing the peptidoglycan carrier with a PEDV subunit antigen of which the amino acid sequence is SEQ ID NO: 1 to obtain the novel PEDV subunit vaccine. The novel PEDV subunit vaccine comprises a peptidoglycan carrier with a specific size, can improve the in-vivo presentation efficiency of an antigen and rapidly induce efficient body fluid and mucous membrane immune response, and is of great significance to research and development of vaccines for porcine epidemic diarrhea diseases and the like.

The invention belongs to the technical field of biomedical treatment and biological fermentation, discloses a metagen composition for effectively inhibiting oral dental caries and application thereof, and aims to solve the problems of great side effect, weak effect and unknown mechanism of the existing dental caries prevention and treatment means. The composition is prepared by mixing a metagen 1 which is prepared by fermenting lactobacillus salivarius Postbio-YY with a metagen 2 which is prepared by fermenting lactococcus lactis Postbio-F3 and lactobacillus paracasei Postbio-P6 step by step. In the preparation process, the active ingredients are reserved by accurately controlling the fermentation pH, time and pasteurization parameters. The composition can be prepared into multiple dosage forms such as toothpaste and the like, can remarkably inhibit the growth of streptococcus mutans and destroy the thallus structure, inhibits biofilm and exopolysaccharide synthesis by down-regulating fimI, wcaJ and wcae genes, is safe and free of side effects, and provides an efficient scheme for decayed tooth prevention and treatment.

The invention relates to the technical field of functional microbial preparations, in particular to a biological preparation for relieving intestinal discomfort caused by alcohol and a preparation method and application thereof.The main technical scheme is that the biological preparation is prepared from, by weight, 5-20 parts of bacillus coagulans, 10-30 parts of pediococcus pentosaceus, 5-10 parts of lactobacillus rhamnosus and 0-20 parts of saccharomycetes. 0-5 parts of bifidobacterium longum and 0-5 parts of lactococcus lactis. By constructing an alcohol metabolism-intestinal protection dual-function synergistic system, specific florae such as bacillus coagulans, pediococcus pentosaceus and lactobacillus rhamnosus are scientifically compatible with functional components such as inulin and L-cysteine, alcohol is efficiently metabolized, and a carbon source is generated; the technical problems of low metabolic efficiency, weak intestinal protection and serious gastric acid inactivation of a traditional product are comprehensively solved.

The invention belongs to the technical field of biological genetic engineering, and discloses a lactococcus lactis carrier oral vaccine for enterotoxigenic escherichia coli F18 fimbriae and application. Four lactococcus lactis antigen surface display strains are prepared and are mixed for oral immunization. The oral immunization mode is convenient to operate, the stress reaction of injection immunization to animals is avoided, meanwhile, the immunization effect is greatly improved, and diarrhea of enterotoxigenic escherichia coli to piglets can be effectively prevented. The escherichia coli vaccine is an oral escherichia coli vaccine, a mouse immune challenge experiment shows that the vaccine can be completely survived under the challenge dosage of LD50, a piglet immune challenge experiment shows that the diarrhea condition of piglets can be completely protected, and it is indicated that an immune group generates effective mucosal immune protection capacity.

The invention relates to selenium-enriched pediococcus acidilactici Se34 with anti-oxidation, cholesterol-lowering and anti-tumor effects and application of the selenium-enriched pediococcus acidilactici Se34. The pediococcus acidilactici Se34 is preserved in the China General Microbiological Culture Collection Center (CGMCC), the preservation number of the pediococcus acidilactici Se34 is CGMCC No.33933, and the preservation date of the pediococcus acidilactici Se34 is March 24, 2025. The pediococcus acidilactici Se34 provided by the invention integrates excellent probiotic characteristics (acid-resistant bile salt, safe and colonizable), efficient selenium enrichment capacity and remarkably enhanced activity of resisting oxidation, reducing cholesterol and inhibiting specific cancer cell proliferation and metastasis after selenium enrichment. The strain and the selenium-rich product thereof have important application value in the fields of developing functional foods (selenium-rich probiotic products), antioxidant / cholesterol-reducing health-care foods, potential auxiliary anticancer biological preparations or prodrugs and the like.

The invention provides lactococcus lactis, a composite dairy leavening agent and application of the lactococcus lactis, the lactococcus lactis has the effects of increasing sweetness and aroma, the classification name of the lactococcus lactis is lactococcus lactis, the preservation number of the lactococcus lactis is CGMCC No.18950, and the preservation date of the lactococcus lactis is November 13, 2019. The strain has the remarkable sweetness increasing and aroma increasing characteristics, and in the fermentation process, the content of the lactococcus lactis in the fermentation process is increased, and the content of the composite dairy leavening agent is increased. Strong FOS (fructo-oligosaccharide) and acetaldehyde generating capacity is shown, endogenous sweet and fragrant flavor substances can be provided for the fermented milk, and the taste and flavor of the fermented milk are remarkably improved. The lactococcus lactis C15, the lactobacillus casei AU9077 and the lactobacillus rhamnosus AU9260 are compounded to obtain the composite dairy leavening agent, the composite dairy leavening agent has a remarkable synergistic effect in the aspect of releasing fructo-oligosaccharide, a stable endogenous sweetening effect is continuously provided for fermented milk, and the requirements of consumers for healthy and flavored dairy products are met while the quality of dairy products is improved.

The invention discloses a streptomyces Targetron gene targeting vector as well as a construction method and application of the streptomyces Targetron gene targeting vector. According to the invention, an II-type intron Ll.LtrB from lactococcus lactis is cloned to an escherichia coli-streptomyces shuttle plasmid to construct a streptomyces genetic manipulation tool-vector pSC30 based on targeting of the II-type intron, and gene targeting in streptomyces coelicolor is successfully realized by using the tool. Screening a biosynthetic gene cluster of red pigment in streptomyces roseosporus; and activating a biosynthetic gene cluster of janus doxorubicin in streptomyces spinosus. According to the invention, the conversion rate and the gene targeting efficiency of the Ll.LtrB intron in streptomyces with high GC content are effectively improved, and a new tool is provided for construction of a gene mutation library.

The application discloses a Vibrio harveyi oral vaccine and a preparation method and application thereof. The application uses a lactococcus lactis NZ9000 expression system, modifies transformation parameters, effectively expresses Vibrio harveyi OmpU protein, constructs a lactococcus lactis (NZ9000) engineering bacterium expressing Vibrio harveyi outer membrane protein (OmpU), develops an oral vaccine against Vibrio harveyi infection, aims to reduce the infection of economic animals in seawater aquaculture by oral administration, provides a new scheme for dealing with the harm of Vibrio harveyi infection and antibiotic resistance and the like, promotes the breeding of fry and fingerlings, and promotes the development of biological agriculture and related industries. The strategy is expected to overcome the problems of traditional injection vaccines, such as inconvenient operation and great stress, and can provide a new technical scheme for reducing the dependence of the aquaculture industry on antibiotics and promoting the establishment of a green and healthy breeding mode.

The invention discloses a method for improving yield of branched chain aldehyde of lactococcus lactis based on regulation and control of a luxS gene and application, and belongs to the field of system biology. Gene function verification and genome scale metabolic network model analysis are creatively combined, the phenotypic effect of the luxS gene is confirmed, and more importantly, the internal action mechanism of the luxS gene is disclosed from the system level, that is, the whole metabolic network flow is influenced by regulating and controlling multiple key enzymes such as transaminase, decarboxylase, dehydrogenase and decarboxylase. The invention reveals that the quorum sensing core gene luxS has a new function of regulating and controlling synthesis of branched chain aldehyde in lactococcus lactis for the first time, and an intercellular communication system is directly linked with production of specific flavor metabolites. The invention provides a brand-new and higher-level regulation target and thought for producing flavor substances by microbial fermentation, and gets rid of the limitation that only metabolic pathway terminal enzyme is singly modified traditionally.

The application discloses a beta-1,4-xylanase mutant and a construction method thereof, and comprises the following steps: constructing a beta-1,4-xylanase recombinant expression vector; introducing the recombinant vector pNZ8048-P5-XynA into a competent lactococcus lactis by using an electrotransformation technology to construct a wild-type expression vector; on the basis, designing and constructing a multi-site mutant recombinant plasmid by using a site-directed mutation method, wherein the eighth asparagine (Asn) of the beta-1,4-xylanase is mutated into tyrosine (Tyr), the 22nd serine (Ser) is mutated into proline (Pro), and the 59th alanine (Ala) is mutated into lysine (Lys); introducing the multi-site mutant recombinant plasmid into the competent lactococcus lactis to construct a heterologous expression strain of the mutant beta-1,4-xylanase (Mut-1); and stably obtaining the mutant xylanase beta-1,4-xylanase (Mut-1) with high activity by using a metal affinity chromatography (Ni 2+ ) method. The specific enzyme activity of the mutant reaches 1929.30±5.36 U / mg, and the optimal temperature is increased by 15 DEG C compared with that of the wild type.

The invention belongs to the technical field of microorganisms, and particularly relates to a method for expressing human lactoferrin by using lactococcus lactis. The method comprises the following steps: step 1, obtaining a codon-optimized hLF gene nucleotide sequence; 2, constructing a recombinant plasmid containing the hLF gene nucleotide sequence obtained in the step 1; and step 3, transferring the recombinant plasmid obtained in the step 2 into lactococcus lactis for induced expression. The heterologous expression of the human lactoferrin hLF is realized by utilizing the lactococcus lactis, the method is low in cost, convenient and fast, and a new way is provided for high-purity and high-yield preparation of the human lactoferrin hLF.

A starter culture for the fermentation of a plant-based milk alternative is provided, which is particularly suitable for the production of a plant-based yogurt alternative. The starter culture comprises lactic acid bacteria isolated from legume plant material, especially pea plant material. Preferably, the starter culture comprises lactic acid bacteria of the species Lactobacillus rhamnosus and / or Lactococcus lactis subsp. cremoris.

The application provides a lactococcus lactis, a compound dairy product fermenting agent and application thereof, the lactococcus lactis has the functions of sweetening and flavoring, and is classified and named as lactococcus lactis Lactococcus lactis The strain has significant sweetening and flavoring characteristics, exhibits strong fructo-oligosaccharide (FOS) and acetaldehyde generation capacity in the fermentation process, can provide endogenous sweet taste and aroma flavor substances for fermented milk, and significantly improves the taste and flavor of the fermented milk.The lactococcus lactis C15 is compounded with lactobacillus casei AU9077 and lactobacillus rhamnosus AU9260 to obtain a compound dairy product fermenting agent, which has a significant synergistic effect in releasing fructo-oligosaccharide, continuously provides stable endogenous sweetening effect for fermented milk, improves the quality of dairy products, and meets the needs of consumers for healthy and flavored dairy products.

This invention aims to address the technical bottlenecks of existing milk curd products, such as weak functional activity, unclear process parameters, and unstable flavor and quality. It utilizes *Pediococcus pentosaceus* HM4, *Streptococcus thermophilus* HM6, *Lactococcus lactis* JY4, and *Lactobacillus plantarum* NC1, employing these four strains in an optimal ratio as a compound fermentation agent to achieve synergistic effects. Using milk and goji berries as raw materials, the fermentation process of milk curds and goji berry milk curds was systematically optimized through single-factor experiments, Plackett-Burman experiments, and response surface methodology. The physicochemical indicators and flavor characteristics of the products under different process conditions were analyzed. The obtained milk curds achieved a DPPH free radical scavenging rate of 91.38%–94.15%, providing technical support for the high-value utilization of milk curds and enriching the variety of functional dairy products.

A composition for use in treating or preventing colorectal cancer (CRC) comprising or a fraction of Lactococcus lactis supernatant having a molecular weight greater than 100 kDa which may be obtained by filtration through a 100 kDa molecular weight filter. The composition also comprises a physiologically acceptable excipient and the fraction may be a protein fraction of the L. lactis supernatant. The composition may be formulated for oral ingestion, a powder, liquid, paste, cream, tablet, capsule, or caplet or in a food or beverage item. Additionally, the composition may be formulated in a daily dosage. Also claimed is a kit for treating or preventing colorectal cancer wherein a first container comprises the fraction of L. lactis culture supernatant.

A cultivation medium for Auricularia auricula that can increase riboflavin content, belonging to the technical field of breeding and cultivation of high-riboflavin Auricularia auricula strains, is composed of basswood sawdust, quicklime, gypsum powder, purified water and a fermented product. The fermented product, calculated by weight, is prepared by mixing 10 - 12 parts of Chrysanthemum morifolium Ramat., 5 - 8 parts of Ginkgo biloba leaves, 3 - 6 parts of Glycyrrhiza uralensis Fisch., 20 - 30 parts of pine cones and 15 - 18 parts of walnut shells into a mixed powder 1, adding chaff, corn flour and sucrose powder to form a mixed powder 2, and then fermenting with Hansenula anomala, Lactococcus lactis and Bacillus licheniformis after sterilization. The cultivation medium prepared by the present invention effectively increases the riboflavin content in Auricularia auricula, reaching more than 2 mg / 100 g of dry Auricularia auricula, shortens the cultivation cycle of Auricularia auricula, and at the same time, the dry Auricularia auricula yield reaches more than 120 g / bag. The above cultivation method can be used for the seedling cultivation of high-riboflavin Auricularia auricula strains, and high-quality strains of high-riboflavin Auricularia auricula can be obtained through the cultivation with this cultivation medium.

The invention belongs to the technical field of gene engineering, and particularly relates to an efficient electrotransformation method of lactococcus lactis BL19. According to the method disclosed by the invention, the electric shock conversion efficiency of the lactococcus lactis BL19 is remarkably improved, and a foundation is laid for genetic engineering transformation in the future.

The present invention relates to the field of biological fermentation. Specifically, it relates to a method and application for fermenting Platycladus orientalis leaves with a composite bacterium, and the composite bacterium includes Lactococcus lactis and Pichia pastoris. The method includes the following steps: (1) pretreatment of Platycladus orientalis leaves; (2) enzymatic treatment of Platycladus orientalis leaves; (3) fermentation of Platycladus orientalis leaves; (4) treatment of the fermentation broth. The present invention has the following beneficial effects: (1) The present invention optimizes the enzymatic hydrolysis parameters, fermentation parameters, and the method for extracting the fermentation broth, and obtains a better fermentation method; (2) The fermentation of Platycladus orientalis leaves in the present invention simplifies the components compared with the fermentation of various traditional Chinese medicine raw materials in the prior art, making the invention more convenient; (3) The mouse experiments of the present invention prove that by using the optimized fermentation method, more flavonoids can be obtained, the anti-hair loss effect is better, and it is more beneficial to the application of Platycladus orientalis leaves.

The present invention relates to a method for improving the antioxidant activity of Lactococcus lactis and its application. The method for improving the antioxidant activity of Lactococcus lactis is to construct a recombinant lactic acid bacterium that produces lycopene, thereby improving the antioxidant activity of Lactococcus lactis. The method for constructing the recombinant lactic acid bacterium that produces lycopene is to construct a lycopene heterologous synthesis plasmid, knock out the lactate dehydrogenase (LDH) gene in Lactococcus lactis or overexpress MVA pathway genes in strains of different sources to obtain the recombinant Lactococcus lactis, thereby achieving heterologous synthesis of lycopene by Lactococcus lactis. Compared with the prior art, the present invention constructs a recombinant lactic acid bacterium that produces lycopene, measures its own antioxidant activity and that in skim milk, and finds that the antioxidant activity of the recombinant Lactococcus lactis is more than 1 times that of the original strain, and the DPPH, ABTS and ·OH free radical scavenging abilities are significantly enhanced. The recombinant Lactococcus lactis is expected to be developed into an antioxidant probiotic product or fermentation agent.