Screening Of Excellent Probiotic And The Study On Probiotic Agent By Fungus Chaff

Along with the problem of antibiotic resistance and antibiotic residues is increasingly serious,probiotic preparation has become the ideal alternatives for antibiotic and been widely applied for the series advantages of supplement,adjustment and maintenance of animal intestinal micro ecological balance,preventing disease,promoting health and improving production performance.In recent years,with the edible fungus technology developed rapidly,and gradually formed the scale and industrial production,fungus chaff is increased rapidly.Within fungus chaff is rich in mycelium and nutrients,reasonable use of fungus chaff is extremely urgent.And it is an important way to use fungus chaff to make probiotic preparation production.According to growth performance,acid production and tolerance,Lactic acid bacteria strains were screened out from our laboratory.and then the biological characteristics of lactic acid bacteria,such as growth performance and acid production,were studied.On the basis of growth performance,tolerance and enzyme production capacity,Bacillus strains were screened out from our laboratory.then the strains were identified and the biological characteristics were studied.This study selected bacillus,lactobacillus and yeast as research target and used fungus chaff as material,fermented via the small pot at laboratory,optimized the fermentation medium and the fermentation conditions,selected excellent strains,which is try to through microbial fermentation to get a high concentration of probiotic preparation.The main results of research are as follows:?1?The result showed that three strains of lactobacillus,R02?Lactobacillus plantarum?,R07?Enterococcus faecalis?and R09?Pediococcus pentosaceus?were screened.R09 has the fastest growth rate and the strongest ability of producing acid.The proportion of lactic acid is the highest in liquid cultures of R09,accounting for 95.45% of the total acid content.Additionly,R09 can survive in 0.12 g/mL NaCl solution.R02 has the strongest tolerance to temperature,which grows well below 55?.R07 has a strong resistance to acid and alkali,which can grow and survive within a wide pH range?3.0 to 9.5?.In the antibiotic susceptibility test,strains R02 and R07 showed strong tolerance,while R09 showed strong resistance.?2?Three strains of bacillus,Ba1?Bacillus amyloliquefaciens?,Bc1?Bacilluscereus?and Bs1?Bacillus subtilis?were screened.The result showed that Bs1 and Bc1 has a strong tolerance to temperature and NaCl solution,and three strains all have a strong resistance to acid and alkali and have a good enzyme production capacity.The results of the growth curve showed that the viable count of three strains were more than 1010cfu/mL,and the viable count of Bc1 reached the highest,was 1014 cfu/mL.The results of antagonistic test showed that Ba1 and Bs1 have a strong inhibitory effect on streptococcus.3 strains have a high SOD activity.Bc1 is highly resistant to antibiotics,Ba1 and Bs1 are sensitive to most antibiotics.?3?With R09 and Bc1 as the starting strain,the optimum medium formula of fungus chaff fermentation: fungus chaff 22.5 g,wheat bran 5.2 g and Scraps of fat 2.5 g,Carbamide 1.2 g.Under this condition,the viable number of R09 is up to 2.5×10⁹ cfu/g and the viable number of Bacillus Bc1 is up to 3.16×10¹⁰ cfu/g.Through the fermentation of R09,Bc1 and 1314,the optimal combination of two groups are obtained: the treatment Bc1+1314+R02+R09 and the treatment Ba1+ 1314+R02+R09.And the treatment of 3 Bc1+1314+R02+R09 fermentation product of pH was significantly lower than the combination of other strains?p<0.05?,crude protein content of fermentation product and reducing sugar content are significantly higher than other strains?p<0.05?combination,compared with the control group,the content of crude protein increased 13.4%,sugar content increased by 108.5%.Through the orthogonal test L₉?3⁴?,the optimum fermentation conditions were obtained.The optimum fermentation condition is: temperature30?,initial pH 4.5,the ratio of material to water was 2:2.7,and the culture time 96 h.Under this condition,the viable count of lactobacillus,bacillus and yeast can reach 2.0×10⁹ cfu/g,8.71×10¹⁰ cfu/g,and 1.95×10⁸ cfu/g.?4?After verification test,the viable count of two strains lactobacillus and bacillus reached 1010cfu/g,the strains of live bacteria had high content of lactobacillus in live bacteria strain compatibility Bc1+1314+R02+R09 number up to 4.27×10¹⁰ cfu/g,Bacillus bacteria8.24×10¹⁰ cfu/g,yeast 7.08×10⁹ cfu/g;the viable count of lactobacillus in Ba1+1314+R02+R09 is 1.58×10¹⁰cfu/g,Bacillus is 5.75×10¹⁰cfu/g and yeast is 2.69×10⁸cfu/g.