【摘要】 通过单因素实验,对已筛选出的产酶菌株N1进行诱变处理,结合甲基橙平板筛选和α-环糊精葡萄糖基转移酶(α-CGTase)活力测定,确定了紫外线和亚硝酸的诱变剂量,获得了一株α-CGTase活力较高的菌株B3。实验结果如下:距离20 W紫外灯30 cm,照射100 s,0.25 mol/L的HNO2处理30 min,效果较好。出发菌株N1酶活为0.62 U/mL,经过诱变获得高产菌株B3酶活力是3.76 U/mL,发酵生产的α-CGTase活力比原始菌株提高了506%。经8代稳定性实验,B3的活力稳定在3.760±0.030 U/mL。更多还原

【Abstract】 In order to obtain a strain(B3) with high α-CGTase activity,the screened enzyme production strains N1 was treated by HNO 2 and UV mutagenesis,screened by methyl orange plate,and determined for the α-CGTase activity.The dose of nitrous acid and UV was ascertained by single factor experiments.The results showed that the effect was good under the condition of being irradiated with 20 W UV lamp in the distance of 30 cm,for 100 s and treated with 0.25 mol / L HNO 2 for 30 min.The enzyme activity of strain N1 was 0.62 U / mL,after mutagenesis the enzyme activity of the strain B3 reached to 3.76 U / mL.Compared with the original stain,the α-CGTase activity of the strain B3 increased by 506%,and kept in 3.760 ± 0.030 U / mL after eight generations.更多还原