Study Of The High Cell Density Fermentation Of Bacillus Coagulans

As one of the novel microbial ecological agents,Bacillus coagulans has been used in various aspects such as medicine,food and feed.The sporation could survive well and go through the stomach to the intestines for probiotic function.Therefore,it is important to improve the living bacterium number and spore concentration.In this paper,by using the method of atmospheric and room temperature plasma(ARTP),strains with good vitality and high spore rate are isolated.Based on the isolated strains,which were of solid fermentation and liquid fermentation were studied.The optimum culture conditions of B.coagulans BC304 in solid-state fermentation were confirmed by single-factor experiment:soyean meal 40%,additional water 60%,corn steep powder 2%,lactose 1%,every bottle(250 mL)was filled with 50g of solid medium,relative humidity 60%and the medium was cultivated at 37? for 48h.In the pure solid-state ferment with 8%inoculums concentrations,the viable counts and the spore counts of B.coagulans BC304 were 7.20×109 CFU/g and 5.80 × 109 CFU/g.The viable count of dried sample were 9.40 × 109 CFU/g.While in the process of mixed ferment with 5%B.subtilis natto,viable counts and the spore counts of B.coagulans BC304 were 9.20× 109 CFU/g and 8.50 × 109 CFU/g.The viable counts of B.coagulans BC304 and B.subtilis nattoin in dried sample were 1.75 ×1010 CFU/g and was 7.82 × 109 CFU/g..The optimal culture condition of liquid medium was determinded as follows(g/L):soyean meal 50,lactose20,corn steep powder 10,calcium carbonate 10,magnesium sulfate 0.2,manganese sulfate 0.2,dipotassium phosphate 1.0,cultivated at 37? for 48 h..In the pure liquid-state ferment 10%with inoculums concentrations,the viable counts and the spore counts of B.coagulans BC304 were 9.20×108 CFU/mL and 8.10×108 CFU/mL.In the process of co-ferment with 8%B.subtilis natto,viable counts and the spore counts of B.coagulans BC304 were 1.20×109 CFU/mL and 1.11×109 CFU/mL.The result of pure ferment of 1 L fermentor was in accordance with the pervious study,while the result of co-ferment showed the opposite.In the pure liquid ferment,viable counts and the spore counts of B.coagulans BC304 were 9.50×109 CFU/mL and 7.92×109 CFU/mL.After dried at the temperature of 60?,the viable counts of the pure ferment sample of B.coagulans BC304 was 1.69 X 1011 CFU/g.In the process of mixed ferment with B.subtilis natto,viable counts and the spore counts of B.coagulans BC304 were 3.60×109 CFU/mL and 6.10×108 CFU/mL.In the dried sample,the viable count of B.coagulans BC304 were 4.10×1010 CFU/g and the viable count of B.subtilis natto was 3.93×109 CFU/g.