【 Principle 】

Protein peptone, beef extract, yeast extract, and glucose provide the necessary carbon and ammonia sources, vitamins, and growth factors for bacterial growth; Tween-80, sodium acetate, phosphate, triammonium citrate, magnesium salts, and manganese salts provide various growth factors required by lactic acid bacteria, while also inhibiting the growth of bacteria other than lactic acid bacteria; Agar is a coagulant.

Main components

Composed of peptone, beef extract, yeast extract, glucose, dipotassium hydrogen phosphate, Tween-80, magnesium sulfate, manganese sulfate, agar, triammonium citrate, sodium acetate, and distilled water.

Storage conditions and expiration date

Storage conditions: This product should be stored in a dark environment at 2-8 ℃.

Validity period: The unopened original packaging has a validity period of 3 months.

This product is a disposable product.

Count of lactic acid bacteria in food: quantitative detection of lactic acid bacteria in fermented foods such as yogurt and kimchi.

Screening of probiotic strains: isolating beneficial bacteria such as Bifidobacterium and Lactobacillus for identification and research and development.

Fermentation environment monitoring: Screening the proportion of dominant lactic acid bacteria in the fermentation workshop and raw material coating samples.

Pure strain propagation amplification: Purified lactic acid bacteria are transferred and amplified for subsequent experiments.

Distinguish between lactic acid bacteria and miscellaneous bacteria: low pH+inhibitors inhibit miscellaneous bacteria and selectively enrich lactic acid bacteria.

Fermentation deterioration traceability: Abnormal fermentation of food with dominant lactic acid bacteria or mixed bacteria contamination.

Short term preservation package: activation and recovery of lactic acid bacteria, preparation of bacterial suspension for fermentation performance testing.

Lactic acid bacteria

Biological characteristics: mostly Gram positive, lactobacilli are rod-shaped with varying lengths, and lactobacilli streptococcus are chain shaped; No spores, no flagella, mostly unpowered; Heterotrophic fermentation of glucose produces a large amount of lactic acid, with strong acid resistance and tolerance to low pH MRS environments; Micro aerobic or anaerobic growth, with weak growth under aerobic conditions; Widely present in fermented foods, human intestines, and probiotic preparations, most of which are beneficial probiotics that regulate gut microbiota. Can tolerate the inhibitory effect of acetate salts, making it difficult for miscellaneous bacteria such as Escherichia coli, Bacillus, and mold to proliferate in this environment.

Plate culture (anaerobic at 36 ℃, 24-48 hours): The colonies are milky white/porcelain white, round and raised, with a smooth and moist surface, neat edges, and some strains are relatively small; Fermented glucose produces acid, no indicator color, no hemolysis, no black precipitate, and slight yellowing around long-term cultured colonies; G ⁻ bacteria such as large intestine and Salmonella are inhibited; Staphylococcus and mold grow very weakly and cannot form dominant colonies.