食品科学 ›› 2019, Vol. 40 ›› Issue (20): 41-46.doi: 10.7506/spkx1002-6630-20181107-087

• 食品化学 • 上一篇    下一篇

pH值对热处理后菠菜和油菜类囊体膜稳定性的影响

曹家蕊,王冰,李方巍,张燕   

  1. (中国农业大学食品科学与营养工程学院,国家果蔬加工工程技术研究中心,北京 100083)
  • 出版日期:2019-10-25 发布日期:2019-10-25
  • 基金资助:
    国家自然科学基金面上项目(31571844);“十三五”国家重点研发计划重点专项(2018YFD0400600)

CAO Jiarui, WANG Bing, LI Fangwei, ZHANG Yan

CAO Jiarui, WANG Bing, LI Fangwei, ZHANG Yan   

  1. (College of Food Science and Nutritional Engineering, China Agricultural University, National Engineering Research Centre for Fruit and Vegetable Processing, Beijing 100083, China)
  • Online:2019-10-25 Published:2019-10-25

摘要: 研究pH值对热处理后菠菜和油菜类囊体膜稳定性的影响,包括类囊体膜的色值、多肽组分、可溶性蛋白含量、类囊体膜吸收光谱以及叶绿素的倒置荧光显像。结果表明:低pH值(3.6、4.6)下菠菜和油菜类囊体膜溶液的-a*值显著降低,叶绿素蛋白复合体的多肽组分明显降解,可溶性蛋白含量显著降低,荧光分布发生聚集(P<0.05)。由此证实,低pH值(3.6、4.6)能够破坏类囊体膜及叶绿素蛋白复合体的结构、功能稳定性,使更多的叶绿素游离出来,加速了叶绿素的降解;相同pH值条件下,菠菜类囊体膜稳定性低于油菜类囊体膜;光系统I叶绿素蛋白复合体较光系统II叶绿素蛋白复合体对低pH值更敏感。

关键词: pH值, 类囊体膜, 叶绿素蛋白复合体, 叶绿素

Abstract: We examined the effects of different pH values on the stability of thylakoid membrane in spinach and oilseed rape after heat treatment in terms of color value, polypeptide composition, soluble protein content, absorption spectrum and inverted fluorescence imaging of chlorophyll. The results showed that the color values (?a*) of spinach and oilseed rape thylakoid membrane solution were significantly decreased at low pH (3.6 and 4.6), the polypeptide components of chlorophyll protein complex were obviously degraded, the soluble protein content was significantly decreased, and the fluorescence distribution was aggregated (P < 0.05). It was confirmed that low pH could destroy the structural and functional stability of thylakoid membrane and chlorophyll protein complex, thus releasing more free chlorophyll and accelerating the degradation of chlorophyll; under the same pH condition, the stability of spinach thylakoid membrane was lower than that of oilseed rape thylakoid membrane. The chlorophyll protein complex of photosystem I was more sensitive to low pH than that of photosystem II.

Key words: pH, thylakoid membrane, chlorophyll protein complex, chlorophyll

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