Fermentation technology by LH(Lactobacillus spp) as a probiotic

Objective To study the liquid medium optimization and fermentation conditions for probiotic strain Lactobacillus spp.Method Suitable culture medium was obtained through testing the effect of single medium elements on growth of LH,including carbon sources,nitrogen sources,inorganic salts and growth factor.The optimal prescription for LH fermentation,as determined by orthogonal design,was composed of molasses 12 g/L,yeast extract 5 g/L,peptone 1 g/L,glucose 4 g/L,corn steep liquor 3 g/L,CH3COONa 5 g/L,NaCl 5 g/L,K2HPO4 2.5 g/L,KH2PO4 2.5 g/L,MgSO4 0.5 g/L,MnSO4 0.25 g/L.Result The optimal fermentation conditions were as follows,based on the above optimal medium: temperature 30～35 ℃,inoculation volume 2%,medium volume 500 ml in 500 ml flask,and static incubation.Under the optimized conditions,the alive cells amount of LH were up to 1.74×109 CFU/ml.Conclusion The growth curve of LH revealed that the optimal inoculation time was at 24 hours and the culture period 36 hours.