CN-122012269-A - Method for improving lactobacillus plantarum metabolite through illumination pretreatment

Abstract

The invention provides a method for improving lactobacillus plantarum metabolites through illumination pretreatment, and belongs to the field of microbial fermentation. The method is to irradiate the strain suspension with visible light for a specific time period and a specific light before activating the lactobacillus plantarum. Compared with a control group which is not subjected to illumination treatment, the lactobacillus plantarum treated by the method has the advantages that the activity of key enzymes in cells is enhanced, the concentration of thalli is almost unaffected, the antioxidant activity is improved, and meanwhile, the yield of extracellular polysaccharide is also effectively improved.

Inventors

• WANG YUEHUA
• LI BIN
• ZHAO TIANTIAN
• LI YUNJIE
• XIE XU
• SUN XIYUN
• GAO NINGXUAN
• JIAO XINYAO

Assignees

• 沈阳农业大学

Dates

Publication Date

20260512

Application Date

20260226

Claims (10)

1. 1. A method for improving the metabolic products of lactobacillus plantarum by light treatment is characterized by comprising the following steps of carrying out light pretreatment on lactobacillus plantarum strains before an activation culture stage of lactobacillus plantarum.
2. 2. The method according to claim 1, wherein the alternating irradiation with red and blue light is performed for 20-100min before the lactobacillus plantarum is activated.
3. 3. The method according to claim 2, wherein the wavelength of red light is 620nm, the wavelength of blue light is 450nm, and the red light and the blue light are alternately irradiated for 40min.
4. 4. The method according to claim 1, wherein the strain used for lactobacillus plantarum is P-8.
5. 5. The method of claim 1, wherein the light-treated object is a liquid bacterial suspension.
6. 6. The method of claim 5, wherein the concentration of the liquid bacterial suspension is 10 6 -10 9 CFU/mL.
7. 7. The method according to claim 1, wherein the light pretreatment is specifically that lactobacillus plantarum activated once is absorbed by 1% of bacterial liquid into sterilized secondary activated culture medium, the bacterial liquid is evenly placed into the same 6-hole plate, the hole plate filled with the bacterial liquid is placed into a dark environment before secondary activation, a light source is arranged at the top, and red and blue lights are respectively irradiated for 20 minutes.
8. 8. The method according to any one of claims 1 to 6, wherein the activation culture stage of lactobacillus plantarum is preceded by a first-generation activation of the strain and followed by a second-generation activation.
9. 9. The method of claim 8, wherein the first activation is performed at a temperature of 37 ℃ for a period of 18-24 hours, and the second activation is performed at a temperature of 37 ℃ for a period of 14-24 hours.
10. 10. The method according to claim 8, wherein the activation culture is performed in MRS liquid medium at 37℃for 16 hours, a first activation time of 24 hours, and a second activation time of 16 hours.

Description

Method for improving lactobacillus plantarum metabolite through illumination pretreatment Technical Field The invention relates to the technical field of microbial fermentation, in particular to a method for improving lactobacillus plantarum metabolites through illumination pretreatment. Background Lactobacillus plantarum is an important lactobacillus and is widely applied to the fields of food fermentation, probiotic preparations, animal husbandry and the like. Has effects in regulating intestinal flora, enhancing immunity, and reducing cholesterol. Its activity and metabolites (e.g., various enzymes and extracellular polysaccharides) directly determine its utility. The enzyme activity affects the metabolic capacity and the functional characteristics, the extracellular polysaccharide is closely related to the probiotics characteristics and the fermentation product quality, and the thallus concentration is a key index for measuring the growth efficiency and the biomass. However, during industrial production, storage and passage through the gastrointestinal tract, the activity and stability of lactobacillus plantarum are affected by various environmental stresses, resulting in a decrease in viable count and reduced function, which greatly limits its utility. At present, the method for improving the activity and the metabolic products of lactobacillus plantarum mainly focuses on optimizing the components of a culture medium (such as adding carbon sources, nitrogen sources and growth factors), changing physical conditions (such as temperature and pH value) or performing strain breeding. Although effective, these methods have some limitations in that the strain breeding period is long and uncertainty is high, adding chemicals to the culture medium may increase cost, and may introduce exogenous components into the final product, which is not suitable for food pursuing "clean tag", and has problems of high cost, complicated operation, etc. Light irradiation is used as a green and physical regulation means, has been applied to the culture of microalgae and certain photosynthetic bacteria, but the systematic influence and the research for directionally improving the activity of thallus and metabolic products are still blank in the culture of non-photosynthetic lactobacillus, especially lactobacillus plantarum. In the prior art, researches on the influence of illumination on lactobacillus are focused on the fermentation process, and the results are different, and even some reports suggest that the illumination can generate free radicals to damage thalli. In the prior art, a key time node of 'before activation' does not exist, and various performances (including enzyme activity, oxidation resistance, extracellular polysaccharide and the like) of lactobacillus plantarum are systematically improved by using light illumination as a pretreatment means. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides a method for improving the metabolic products of lactobacillus plantarum through illumination treatment, which comprises the following steps of carrying out illumination pretreatment on lactobacillus plantarum strains before an activation culture stage of lactobacillus plantarum. Further, before lactobacillus plantarum is activated, red and blue light is alternately irradiated for 20-100min. Further, the wavelength of red light is 620nm, the wavelength of blue light is 450nm, and the red light and the blue light are alternately irradiated for 40min. Further, the strain adopted by the lactobacillus plantarum is P-8 Further, the object of the light treatment is liquid bacterial suspension. Further, the concentration of the liquid bacterial suspension is 10 6-109 CFU/mL. Further, the light pretreatment is specifically that lactobacillus plantarum which is activated once is absorbed by 1% of bacterial liquid into a sterilized secondary activated culture medium, the bacterial liquid is evenly placed into the same 6-hole plate, the hole plate filled with the bacterial liquid is placed into a dark environment before secondary activation, a light source is arranged at the top, and red and blue light is respectively irradiated for 20 minutes. Further, the lactobacillus plantarum is specifically before the activation culture stage, specifically after the first generation of activation of the strain and before the second generation of activation. Further, the first activation is carried out at 37 ℃ for 18-24 hours, preferably 24 hours, and the second activation is carried out at 37 ℃ for 14-24 hours, preferably 16 hours. Further, the activation culture is carried out in MRS liquid culture medium, the culture temperature is 37 ℃, the time is 16 hours, the first-generation activation time is 24 hours, and the second-generation activation time is 16 hours. The technical scheme of the invention has the following advantages: The invention provides a method for improving the metabolic products