脉冲强磁场对牛乳中酶的构象的影响  

Effect of pulsed high magnetic field on the enzyme conformation of milk

作　　者：陈仁菊[1] 郭丹丹[1] 肖凯军[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7期82-85,共4页Science and Technology of Food Industry

基　　金：国家863计划项目(2007AA100405)

摘　　要：采用荧光光谱技术和圆二色谱法分析方法,通过对分析脉冲强磁场处理前后牛奶中乳过氧化物酶和牛奶粗酶液中荧光光谱和圆二色谱的综合分析,对牛奶中乳过氧化物酶活性的变化机理进行了初步探讨。结果表明:牛奶粗酶液的二级结构无明显改变,而三级结构发生了明显改变——荧光峰发生了0.6nm的偏移,且荧光强度有明显变化;但牛奶中乳氧化物酶的三级结构无明显变化,但其二级结构发生了明显改变——α-螺旋向其它结构形式(β类结构或无规则卷曲)转变。初步推断,脉冲强磁场处理后,粗酶液中不同酶类的二级结构发生了相反的变化,相互抵消,最终导致牛奶粗酶液中蛋白二级结构整体无明显变化。By analysising the fluorescence spectrum and circular dichroism spectrum of the milk peroxidase and milk crude liquid enzymes in milk before and after pulsed high magnetic field treatment, the mechanism of milk peroxidase activity change was preliminary studied.And the results showed that the milk crude enzyme of milk had no significant change on the secondary structure as a whole, but there was a clear change in the third level structure--its fluorescence peak had a migration of O.6nm and fluorescence intensity change was not obvious. However,as for the milk peroxidase,there was no obvious change in its third level structure, but there was an apparent change in its secondary structure（alpha helix structure changed to other forms of structure such as β structure or other curly without rules）.According to the preliminary inference, after the treatment of pulsed high magnetic field,the secondary structure of enzymes in the crude enzyme of milk changed to different direction, offsets with each other,and made the crude enzyme had no significant change in whole.

关 键 词：脉冲强磁场 圆二色谱 荧光光谱 乳过氧化物酶 

分 类 号：TS252.1[轻工技术与工程—农产品加工及贮藏工程]