Effects of Light and Photosynthetic Electron Transport System on the Generation of Singlet Oxygen ($^1$O$_2$) in Ginseng Thylakoid Membrane

인삼 틸라코이드에서 Singlet Oxygen($^1$O$_2$) 생성에 미치는 전자전달계의 영향

  • Yang, Deok-Cho (Department of Biology, College of Natural Science, Chungbuk National University) ;
  • Chae, Quae (Department of Biochemistry, College of Natural Science, Chungbuk National University) ;
  • Lee, Sung-Jong (Department of Biology, College of Natural Science, Chungbuk National University) ;
  • Kim, Yong-Hae (Department of Biology, College of Natural Science, Chungbuk National University) ;
  • Kang, Young-Hee (Department of Biology, College of Science, Yonsei University)
  • 양덕조 (충북대학교 자연과학대학 생물학과) ;
  • 채쾌 (충북대학교 자연과학대학 생화학과) ;
  • 이성종 (충북대학교 자연과학대학 생물학과) ;
  • 김용해 (충북대학교 자연과학대학 생물학과) ;
  • 강영희 (연세대학교 이과대학 생물학과)
  • Published : 1990.04.01

Abstract

In order to Investigate the mechanism of the leaf-burning disease of ginseng (Panax ginseng C.A. Meyer), studies on the generation of singlet oxygen (1O2) and the photooxidation of the pigments were carried out in comparison with the ones of soybean (G1ycine max L). The studies were mainly focalized on the effects of light intensity, light intensity, inhibitor and electron donor/acceptor of the Photosynthetic electron transport system. When we measured the amounts of 1O2 generated in the thylakoids of ginseng and soybean by the irradiation of light (300 w/m2) as a function its time. It was identified that a higher amount of 1O2 was formed in the ginseng thylakoid than the case of soybean. A generation ratio of lO2 between ginseng and soybean sltbstantially identical in the range of light intensities 50∼150w/m2 However much higher amount of 1O2 was generated in ginseng by irradiation of strong intensity of light (200 500w/m2). Wave length dependency on the generation of 1O2 and the pigment photooxidation was observed on ginseng thylakoids; red light (600-700 nm) gave a maximum effect in the contrast with blur green light (400-60 nm). When the ginseng thylalioid was treated with the electron donor (Mn2+) and acceptors (DCPIP, FeCy) of the photosynthetic electron transport system. a drastic inhibition of 1O2 generation was observed. However, treatment with its inhibitors (DCMU, KCW) activated 1O2 generation. An interesting fact that an electron donor or acceptor of the photosystem II(P680) Inhibited 1O2 generation, suggests an intimate relationship between 1O2 generation and photosystem II.