超声波辅助酶法提取甜玉米穗轴黄酮及抑菌性检测

Ultrasonic-Assisted Enzymatic Extraction and Antimicrobial Activity of Sweet Corncob Flavonoids

以甜玉米穗轴为原料,利用超声波辅助纤维素酶法提取其中的黄酮类物质,考察纤维素酶作用的酶解时间、酶解温度、pH值以及酶用量对甜玉米穗轴中黄酮类物质提取效果的影响。结果表明:超声波辅助纤维素酶法提取黄酮类物质最佳工艺条件为:超声处理20 min后,酶解温度55℃、pH 4.8、纤维素酶用量0.008 g/2.0 g甜玉米穗轴、酶解时间1.5 h,此条件下甜玉米穗轴中黄酮类物质提取率0.318%。甜玉米穗轴中黄酮类物质对白葡萄球菌、大肠杆菌和枯草芽孢杆菌有明显的抑制作用,最低抑菌质量浓度分别为0.5、0.25、2 mg/mL。

Flavonoids were extracted by ultrasonic-assisted enzymatic hydrolysis of sweet corncobs using cellulase and the optimal extraction conditions were established by orthogonal array design. An ultrasonication time of 20 min followed by enzymatic hydrolysis at 55 ℃ and pH 4.8 for 1.5 h with an enzyme dosage of 0.008 g/2.0 g substrate provided maximum extraction yield of 0.318%. The flavonoids extracted from sweet corncobs had significant antibacterial activity against whiteStaphylococcus, Escherichia coli and Bacillus subtilis. The minimum inhibitory concentrations were 0.5, 0.25 and 2 mg/mL respectively.