基于FTIR和RF方法探究超声波对SAP_(MW<1ku)结构的影响  

Effect of Ultrasonic Technology on the Structure of SAP_(MW<1ku) Based on FTIR and RF Methods

作　　者：怀影 于亚莉[1] 刘静波[1] 张婷[1] Huai Ying;Yu Yali;Liu Jingbo;Zhang Ting(Key Laboratory of Nutrition and Functional Foods,School of Food Science and Engineering,Jilin University,Changchun 130062)

机构地区：[1]吉林大学食品与工程学院营养与功能食品重点实验室,长春130062

出　　处：《中国食品学报》2018年第10期178-186,共9页Journal of Chinese Institute Of Food Science and Technology

基　　金：长春市"双十工程"项目(15SS09)

摘　　要：为探究超声波提高大豆抗氧化肽活性机制,以分子质量<1 ku的大豆抗氧化肽(SAP_(MW<1ku))为研究对象,以2,2-二苯基-1-苦基肼(2,2-diphenyl-1-picrylhydrazyl,DPPH)自由基清除率为衡量指标,通过单因素和响应面试验,优选超声波技术处理SAPMW<1的最佳工艺参数。研究表明,超声功率320 W,超声时间24 min,工作间歇比3/3,超声波处理的SAPMW<1的DPPH自由基清除率比未经超声波处理提高了13.08%。借助傅里叶变换红外光谱(FTIR)、荧光光谱(RF)、Zeta电位技术,分析超声波对其结构的影响。FTIR分析显示,经超声波处理的样品C=CH2、-CH3键发生改变;RF分析表明,超声处理样品与未超声处理样品相比发生红移及荧光强度改变,表明超声波处理的SAP_(MW<1ku)蛋白结构发生改变;同时,在优化条件下超声波处理Zeta电位绝对值升高8.63 m V,推测经超声处理, SAP_(MW<1ku)结构更加无序,官能团暴露,肽活性改变。本文为进一步探究超声波技术提高抗氧化肽活性机理提供理论基础。Enzymatic preparation of natural antioxidant peptides with the help of high-tech methods were becoming increasingly mature. SAPMW〈1ku was chosen to investigate the improvement of antioxidant activity of peptides treated with ultrasonic technology. The effects of ultrasonic power, ultrasonic time and work interval ratio on SAPMW〈1ku were evaluated using 2,2-diphenyl-1-picrylhydrazyl （DPPH） radical inhibition. The optimum parameters of ultrasonic treatment of SAPMW〈1ku, were optimized through single factor and response surface experiments, as well as the effect of ultrasonic tech- nology on its structure was analyzed by Fourier transform infrared （FTIR）, Fluorescence spectrum （RF） and Zeta poten- tial. Using a response surface methodology （RSM） experiment, it was shown that when ultrasonic power was 320 W, ul- trasonic time was 24 min, work interval ratio was 3/3, the DPPH radical inhibition of SAPMW〈1ku increased by 13.08% compared with the non-uhrasonic treatment sample. Furthermore, FTIR analysis indicated that the ultrasonic-treated SAPMW〈1ku under optimal conditions added the characteristic absorbance of C=CH2, and-CH3; Fluorescence spectrum analy- sis indicated that the ultrasonic-treated SAPMW〈1ku was in red shift and fluorescence intensity decreased, because the hy- drophobic groups within the ultrasonic-treated SAPMW〈1ku are exposed to the solution and the protein structure was changed. As well as the ultrasonic-treated SAPMW〈1ku of Zeta potential was decreased by 8.63 mV, it was further speculated that SAPMW〈1ku was more disordered by ultrasonic treatment, resulting in the exposure of functional groups and the change of antioxidant activity of SAPMW〈1ku. This study provides a theoretical basis for further exploration of the active mechanism of ultrasonic technology to improve antioxidant peptides.

关 键 词：超声波 大豆抗氧化肽 ZETA电位 中红外色谱(FTIR) 荧光光谱(RF) 

分 类 号：TS201.2[轻工技术与工程—食品科学]