选择合适的米曲霉固态发酵条件对苦荞发酵过程中产生的多肽含量及发酵产物液的抗菌活性至关重要,在单因素试验的基础上,首先采用Plackett-Burman试验设计筛选出影响苦荞多肽含量及发酵产物液抗菌活性的四个主要因素:接种量、加水量、磷酸氢二钾添加量、发酵时间.随后以苦荞多肽含量为响应值,采用Box-Behnken试验设计及响应面分析法优化米曲霉固态发酵10g苦荞的发酵条件,得到最佳发酵工艺参数:接种量为1.97mL,加水量为4.06mL,磷酸氢二钾添加量为0.34%,发酵时间为2.17d.在此条件下苦荞多肽理论含量为39.62mg/mL、实际苦荞多肽含量为 (39.18±1.11)mg/mL,且此时发酵产物液对大肠杆菌和金黄色葡萄球菌的抑菌率分别为 (98.39±0.57)%和(98.55±0.75)%.表明Plackett-Burman设计结合响应面分析法可以很好地对苦荞多肽及具有抗菌活性的发酵产物液的发酵工艺进行优化,可为苦荞多肽及发酵产物液抗菌活性成分的深入研究和广泛应用提供一定的技术支撑.%Selecting appropriate solid-state fermentation conditions ofAspergillusoryzae is essential for tartary buck-wheat peptide content and antimicrobial activity of fermentation product liquid during its fermentation. On the basis of single factor experiment results, inoculums size, water addition amount,potassium hydrogen phosphate addition amount and fermentation time were identified as main factors that influence tartary buckwheat peptide content and antimicrobial activity of fermentation product liquid with the Plackett-Burman experiment design firstly. Then the Box-Behnken experiment design and response surface analysis were adopted optimize conditions to use for tartary buckwheat of 10g by solid-state fermentation with tartary buckwheat peptide content as the response value. The optimum process conditions were as followed: inoculums size of 1.97mL, water addition amount of 4.06mL,potassi-um hydrogen phosphate addition amount of 0.34%, fermentation time 2.17d, tartary buckwheat peptide content in the theoretical value of 39.62mg/mL, actual measurement value of (39.18±1.11)mg/mL, and the inhibition rate of E. coli and S. aureuswere (96.62±1.66)% and (97.54±0.54)% respectively. 1.41%, which indicated that the com-bination of Placket-Burman design and response surface analysis can well optimize of tartary buckwheat peptide content and antimicrobial activity of fermentation product liquid and it can provide certain technical support for the widely used of tartary buckwheat peptide content and antimicrobial activity of fermentation product liquid.
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