| Probiotics are cultured bacteria and their metabolites substance preparations in general. On the one hand probiotics for adjust and improve the level of human, animal or plant host health, on the other hand probiotics can facilitate the growth of normal flora in host body. Present, research on the development of probiotics has a great investment. Probiotics used as new generation of a substitute for antibiotics, because of its no pesticide residue, non-toxic side effects and does not cause biological resistance. Probiotics containing Lactobacillus produce organic acids and their metabolites helps to inhibit the growth of a number of pathogens, and it can activate the body’s immune factors, enhance immunity. Lactobacillus as a new feed additive, can promote the growth of animal bones, prevent intestinal diseases, and help improve the ecological environment, and therefore Lactobacillus has been widely used in many fields.This paper study on Lactobacillus plantarum, division of Lactobacillaceae, which belonging to the anaerobic and fermentation metabolic pathways, Bacteria morphology of straight, curved Brevibacterium, single, sometimes in pairs or in a chain. The most suitable growth temperature condition was30℃-35℃, pH value was6.5. This paper based on the biological characteristics of Lactobacillus plantarum, respectively study on optimization the liquid and solid-state fermentation process, high temperature strain drying, drying protective agents and drying storage for research, the results of the study as follows:1. By single factor experiment, optimize Lactobacillus plantarum liquid fermentation medium, medium components identified were:Sucrose2.0%, Soy peptone2.5%, Yeast extract2.5%, Sodium acetate0.5%, Citrate dibasic ammonium0.2%, KH2PO40.2%、 MnSO4-H2O0.05%, MgSO4·7H2O0.025%, Sodium thioglycolate0.02%, L-cysteine hydrochloride0.05g%, Calcium chloride anhydrous0.01%, Tween800.1%, optimum fermentation conditions were:strain age were8h, flask cultivation loading capacity is not required, inoculum7.0%(2.7×108CFU/g), fermentation temperature37℃, fermentation time18h. Culture process optimization conditions, spray-dried Lactobacillus plantarum fermentation agent in the water content of7.2%, the number of viable cells reached2.7×1010CFU/g, which was increased an order of magnitude.2. By single factor experiment, optimizing Lactobacillus solid state fermentation medium, we determine the optimal ratio of solid state fermentation medium matrix A and matrix B is3:1, mixing ratio of material to water ratio is1:1, optimum fermentation conditions as follows:strain age8h, inoculation amount7.0%(2.7×108CFU/g) canned flasks loading capacity is40g, the height is4cm, fermentation temperature37℃, fermentation time is24h. With process of optimization, the Lactobacillus in water content of7.8%, the number of viable cells reached2.4×1010CFU/g.3. Screening drying protective agent, then research results show that the addition of5%A protective agent, bacterial content of liquid fermentation agent bacterial content up to2.7×1010CFU/g, bacterial content of solid state fermentation agent up to2.4×1010CFU/g.4. Study on relationship between drying process of Lactobacillus fermentation agent and the cell survival. In the later period of drying stag, the number of viable bacteria was positively correlated with the moisture content of dried material. But the number of viable bacteria was opposite which was correlated with the drying temperature. The number of viable cells of material and temperature relationship is not very obvious, when the water of Lactobacillus fermentation agent was low. Lower the drying temperature and moisture content of materials, can improve the survival rate of preservation agents. The drying temperature is60℃, the water content after drying was7.8%of the number of bacteria was2.4×1010CFU/g.5. Study on storage temperature and storage time effects on Lactobacillus fermentation agent cell survival. The fermented liquid spray dried Lactobacillus fermentation agent and solid-state fermentation of Lactobacillus plantarum fermentation agent, respectively,4℃,37℃and room temperature in winter and spring three different temperatures sealed storage, testing every15d cell viability in a fermentation agent. The results show that,4℃conditions, spray-dried and forced air dried Lactobacillus fermentation agent in cell viability within180d was55.6%and83.4%, in winter and spring at room temperature, spray-dried and dried fermentation agent in cell viability within180d was35.2%and46.5%, at37℃, spray-dried and dried Lactobacillus plantarum ferment within the cell viability in90d was34.5%and42.9%... |
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