【作者】 张鹰； 曾新安；

【Author】 Ying Zhang~a Xinan Zeng~b (a College of Light Industry and Food Technology,Zhongkai Agricultural University, Guangzhou,510225,China; b College of Light Industry and Food Technology,South China University of Technology, Guangzhou,510640,China)

【机构】 仲恺农业工程学院轻工食品学院； 华南理工大学轻工与食品学院；

【摘要】 目的:本实验旨在研究高强脉冲电场(high intensity pulsed electric field,HTPEF)处理对酿酒酵母(CICC1308 S.cerervisiae)细胞内蛋白质的影响效果。方法:采用考马斯亮蓝法测定酿酒酵母经HIPEF处理前后胞内和胞外蛋白质含量,采用高效液相色谱仪(HPLC)检测酿酒酵母经HIPEF处理前后胞内和胞外氨基酸含量。结果:结果显示随着电场强度在5～15kV/cm范围不断增大时,酿酒酵母细胞外的蛋白质含量随着电场强度的增大而增大,但当电场强度大于20kV/cm后,随着电场强度的增大,胞内和胞外的蛋白质含量反而出现减小的趋势;HPLC测得细胞内和胞外的游离氨基酸增加显着,36kV/cm,133ms的脉冲条件使胞外游离氨基酸含量由0.586mg/100mL显著增加至21.42mg/100mL。讨论:由此判断酿酒酵母细胞蛋白质在高强度脉冲电场条件下发生了降解,其可能原因是电场处理可能不仅导致了酿酒酵母细胞膜的穿孔,同时使得内部液泡内被束缚的蛋白酶流出,使得蛋白酶有机会接近细胞质,从而使细胞质蛋白被蛋白酶水解成小片段的缩氨酸和氨基酸。更多还原

【Abstract】 Effect of high intensity pulsed electric field(HIPEF )on the content of protein of S.cerervisiae was studied in this paper.Coomassie blue staining method was used to detect the content of the protein of S. cerervisiae cells before and after HIPEF treatment.And the free amino acids contents in cells suspensions before and after PEF treatment were measured by HPLC.Results shows that the content of extracellular protein increased with the increase of applied electric field strength(5～15kV/cm),while the content of cell protein had a decline trend when electric field strength exceeding 20kV/cm,and HPLC results showed that the contents of cell free amino acids were significantly increased,eg,when the electric field was 36kV/cm and treatment time was 133ms,the free amino acids content increased from 0.586 mg/100mL to 2l.42mg/100mL,which implied that PEF treatment led to degradation of the cells protein.The possible reason is that that electric field treatment may not only lead to the yeast cell membrane perforation,while also result in the internal vacuole bound protease outflow,and so the protease has access to the cytoplasm,thereby allowing the cytoplasmic protein hydrolysis into small fragments of peptides and amino acids by protease.更多还原