Optimization and stabilization of antifungal protein from Bacillus amyloliquefaciens strain HRH317

This paper is concerned with the antifungal protein extraction from the strains Bacillus amyloliquefaciens HRH317.The inhibitive circle diameter as evaluating indicator, the fermentation condition were optimized by single factor experiments and response surface methodology ( RSM) .The results showed the optimized extraction parameters were that the initial p H value of nutrient broth medium ( NB) was 7, inoculation volume of 4%, 37 ℃, and the shaker rotation speed 200 r/min.The inhibitive circle diameter was up to 21.85 mm.The results indicated that the antifungal protein was proved to have strong inhibition effect.The antifungal protein was tested to have strong tolerant to proteinase K, which could be steady with 40~80 ℃ and p H2~11.