超声波及热处理对柚皮苷酶稳定性及其二级结构的影响  

Effect of ultrasonic and heat treatment on the activity and secondary structure of naringinase

作　　者：曾霖霖[1] 黄惠华[1] 

机构地区：[1]华南理工大学轻工与食品学院,广东广州510640

出　　处：《食品工业科技》2011年第8期101-104,共4页Science and Technology of Food Industry

基　　金：国家星火计划项目(2007EA780005);广东省关键领域重点突破项目(2008A024200003)

摘　　要：研究了超声波及热处理对柚皮苷酶的活性及热稳定性的影响,通过圆二色谱分析超声波及热处理对柚皮苷酶二级结构的影响。结果表明,随着温度的升高,酶失活速率加快,在80℃下保温150min,柚皮苷酶残留酶活仅为原酶的15.69%。超声功率为40～120W时,短时间的超声处理对柚皮苷酶活性有促进作用,而功率大于160W时超声波处理对柚皮苷酶活性有钝化作用。80W处理对柚皮苷酶的热稳定性有促进作用,处理5min后60℃保温150min,酶活性比未经处理的柚皮苷酶活性增加了64.34%;而280W处理对柚皮苷酶的热稳定有钝化作用,处理40min后60℃保温150min,酶活性比未经处理的柚皮苷酶活性降低了42.61%。圆二色谱分析结果表明,未经处理的柚皮苷酶中α-螺旋含量较少,主要结构为β-折叠和无规则卷曲;热处理及超声波处理对α-螺旋结构几乎没有影响,β-折叠、β-转角及无规则卷曲含量的变化分别在0.4%～1.1%、0.1%～0.4%及0～0.9%之间。The effects of ultrasonic and heat treatment on the activity and secondary structure of naringinase were studied.The results showed that the activity of naringinase was found decreased to 15.69% with heat treatment for 150min at 80℃.Naringinase activity was found enhanced with ultrasonic treatment for a short time from 40W to 120W,but inhibited once the ultrasonic power higher than 160W.The thermostability of naringinase was promoted under 80W ultrasonic treatment,but passivated under 280W.Naringinase activity was increased by 64.34% under 80W,5min ultrasonic treatment,while decreased by 42.61% under 280W,40min ultrasonic treatment.CD detection showed that the content of α-helix remained steady under heat and ultrasonic treatment,while the content changes of β-sheet,β-turn and random were found from 0.4% ~ 1.1%,0.1% ~ 0.4% and 0 ~ 0.9%,respectively.

关 键 词：柚皮苷酶 超声波 热处理 圆二色谱 二级结构 

分 类 号：TS255.1[轻工技术与工程—农产品加工及贮藏工程]