Screening and Properties of Probiotic Bacillus

Screened from a collection of bacillus bacteria,the antibacterial and protease-producing Brevibacillus formosus FJAT-10011 was selected.Characteristics of the protease and antibacterial properties of its fermentation supernatant were studied.The peak activity of the protease was found at pH 6.0and 40℃.However,the enzyme remained stable below40℃ and between pH 5.0and 9.0.The anti-enterobacterial component of the supernatant exhibited a high temperature stability–its activity decreased merely 20%at 80℃in 30 minutes.Furthermore,the stability was the highest in the range of pH 6.0to 8.0,and not affected by proteinase K,pepsin or trypsin.In addition,FJAT-10011 could also inhibit Fusarium oxysporum,similar to the effect by the antibiotic,hygromycin,at 1mg·mL-1.