Influences of nano-TiO2 on the chloroplast aging of spinach under light.
The effects of nano-TiO2 (rutile) on the chloroplast aging of spinach under light were studied. The results showed that when the chloroplasts were illuminated for 1, 5, and 10 min with 500 micromol/cm2/min light intensity, respectively, the evolution oxygen rate was rapidly increased; when the chloroplasts were treated for 20, 30, and 40 min with 500 micromol/cm2/min light intensity, respectively, the evolution oxygen rate was gradually decreased. While spinach was treated with 0.25% nano-TiO2, the rate of evolution oxygen of chloroplasts in different illumination times (1, 5, 10, 20, 30, and 40 min) was higher than that of control, and when the illumination time was over 10 min, the reduction of the evolution oxygen rate was lower than that of control. It suggested that nano-TiO2 treatment could protect chloroplasts from aging for long-time illumination. The mechanism researches indicated that nano-TiO2 treatment could significantly increase the activities of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD), decrease accumulation of reactive oxygen free radicals and the level of malondialdehyde (MDA), and maintain stability of membrane structure of chloroplast under light.
Hong
Fashui
F
College of Life Sciences, Suzhou University, Suzhou-215006, People's Republic of China.
Yang
Fan
F
Liu
Chao
C
Gao
Qing
Q
Wan
Zhigang
Z
Gu
Fugen
F
Wu
Cheng
C
Ma
Zhenni
Z
Zhou
Juan
J
Yang
Ping
P
D002374:Catalase / Q000378:metabolism; D002736:Chloroplasts / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects*; D007425:Intracellular Membranes / Q000187:drug effects; D008027:Light; D010539:Permeability / Q000187:drug effects; D010544:Peroxidases / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects*; D017382:Reactive Oxygen Species / Q000378:metabolism; D036226:Seedlings / Q000187:drug effects / Q000502:physiology; D018724:Spinacia oleracea; D013268:Stimulation, Chemical; D013482:Superoxide Dismutase / Q000378:metabolism; D014025:Titanium / Q000494:pharmacology*
D017382:Reactive Oxygen Species; C009495:titanium dioxide; D014025:Titanium; D010544:Peroxidases; D002374:Catalase; D013482:Superoxide Dismutase