旋转回归法优化大蒜汁处理条件对大肠杆菌的抑制作用

Optimization of treatment conditions of garlic extract on inhibition effect on E.coli with quadratic rotary design

大蒜对许多微生物有很好的抑菌效果。研究了以原汁浓度100%为基础,对肉制品中常见的腐败菌和致病菌-大肠杆菌、假单胞菌、金黄色葡萄球菌为供试菌,筛选出对大蒜汁最敏感的菌-大肠杆菌为研究对象,经不同pH值和温度处理的大蒜汁对大肠杆菌的抑制作用,并利用旋转回归法研究了大蒜汁处理条件的2个重要因素:温度和pH值对大肠杆菌抑菌的影响,并拟合出回归方程。经回归分析表明,大蒜汁处理条件温度和pH值的取值及其配比对大肠杆菌抑菌有显著影响。通过岭脊分析寻优得出:温度最佳值为35℃、pH最佳值为6.5,在此优化条件下大肠杆菌的抑菌圈直径可以达到3.9cm,比优化前提高了30%。

Garlic has significant antibacterial effect. Using 100% garlic extract as raw material, effects of extracts on main putrefying and pathogenic bacteria of meat, such as E. coli, Pseudomonas, Staphylococcus aureus were studied first. The most sensitive strain-E .coil was selected as bacteria for study on inhibition effect of garlic extract treated with different pH and temperature. Effect of treating pH and temperature of garlic extract on inhibition effect on E. coli was studied with quadratic rotary design. Regression analysis indicated treating temperature, pH and composition of garlic extract have significant effects on inhibition effect of garlic extract on E. coli. The optimum treating conditions, which were temperature under 35℃ and pH at 6.5, were obtained after ridge analysis. And under the optimum conditions, the diameter of inhibition zones of E. coli could reach 3.9cm, improved by 30%.