远红外辐射对山药多酚氧化酶活性及构象的影响  

Effects of far-infrared radiation on activity and conformation of polyphenol oxidase of yam

作　　者：韩彦辉 钟靖涵 孙雪[1] 刘云宏[1,2,3] HAN Yan-hui;ZHONG Jing-han;SUN Xue;LIU Yun-hong(School of Food and Bioengineering,Henan University of Science and Technology,Luoyang,Henan 471000,China;Food Green Processing and Quality and Safety Control of Henan Province International Joint Laboratory,Luoyang,Henan 471000,China;Food Microbiology Engineering and Technology Research Center of Henan Province,Luoyang,Henan 471000,China)

机构地区：[1]河南科技大学食品与生物工程学院,河南洛阳471000 [2]食品绿色加工与质量安全控制河南省国际联合实验室,河南洛阳471000 [3]食品微生物河南省工程技术研究中心,河南洛阳471000

出　　处：《食品与机械》2023年第5期132-138,共7页Food and Machinery

基　　金：河南省科技攻关项目(编号:212102110080);河南省高校科技创新人才项目(编号:19HASTIT013)。

摘　　要：目的:探讨远红外辐射加热对山药多酚氧化酶活性及构象的影响。方法:采用不同的远红外辐射温度对山药进行预处理,研究不同远红外辐射温度对山药多酚氧化酶(PPO)活性、褐变度、总酚含量及PPO构象的影响。结果:当辐射温度为260℃时,处理11 min后PPO酶活仍未钝化,辐射温度高于260℃时,PPO在3~7 min内即可失活;褐变度与总酚含量不随辐射温度的升高和处理时间的增加而规律性变化。经远红外预处理后,随着辐射温度的升高,无规则卷曲和α-螺旋含量有轻微的变化,β-转角减少、β-折叠增加,表明远红外改变了PPO的二级结构。PPO紫外光谱蓝移,荧光光谱红移,表明PPO三级结构发生改变。结论:远红外辐射加热能改变山药中PPO构象并有效钝化PPO活性。Objective:This study aimed to investigate the effect of far infrared radiation heating on the oxidase activity and conformation of polyphenol oxidase(PPO)of yam.Methods:By using different far infrared radiation temperatures,the effects of different far infrared radiation temperatures on yam PPO activity,browning degree,total phenol content and PPO conformation were studied.Results:When the radiation temperature is 260℃PPO enzyme is not deactivated after 11 min.When the radiation temperature is higher than 260℃,PPO can be inactivated within 3~7 min.However,the browning degree and total phenol content did not change regularly with the increase of radiation temperature and treatment time.After far-infrared pretreatment,the contents of random curling andα-helix changed slightly with the increase of radiation temperature,whileβ-angle decreased andβ-folding increased,indicating that far-infrared radiation changed the secondary structure of PPO.The ultraviolet spectrum of PPO shifted blue and fluorescence spectrum shifted red,indicating that the tertiary structure of PPO changed.Conclusion:Far-infrared radiation heating can change the conformation of yam PPO and eventually deactivate it.

关 键 词：远红外辐射 山药 多酚氧化酶 酶活性 构象 

分 类 号：TS215[轻工技术与工程—粮食、油脂及植物蛋白工程]