Effects of Nanoanatase TiO2 on photosynthesis of spinach chloroplasts under different light illumination.
With a photocatalyzed characteristic, nanoanatase TiO2 under light could cause an oxidation-reduction reaction. Our studies had proved that nano-TiO2 could promote photosynthesis and greatly improve spinach growth. However, the mechanism of nano-TiO2 on promoting conversion from light energy to electron energy and from electron energy to active chemistry energy remains largely unclear. In this study, we report that the electron transfer, oxygen evolution, and photophosphorylation of chloroplast (Chl) from nanoanatase-TiO2-treated spinach were greatly increased under visible light and ultraviolet light illumination. It was demonstrated that nanoanatase TiO2 could greatly improve whole chain electron transport, photoreduction activity of photosystem II, O2-evolving and photophosphorylation activity of spinach Chl not only under visible light, but also energy-enriched electron from nanoanatase TiO2, which entered Chl under ultraviolet light and was transferred in photosynthetic electron transport chain and made NADP+ be reduced into NADPH, and coupled to photophosphorylation and made electron energy be transformed to ATP. Moreover, nanoanatase h+, which photogenerated electron holes, captured an electron from water, which accelerated water photolysis and O2 evolution.
Lei
Zheng
Z
College of Life Sciences, Suzhou University, Suzhou 215123, People's Republic of China.
Mingyu
Su
S
Chao
Liu
L
Liang
Chen
C
Hao
Huang
H
Xiao
Wu
W
Xiaoqing
Liu
L
Fan
Yang
Y
Fengqing
Gao
G
Fashui
Hong
H
D015086:2,6-Dichloroindophenol / Q000737:chemistry; D002736:Chloroplasts / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D004579:Electron Transport / Q000187:drug effects; D008027:Light; D053761:Nanocomposites; D010777:Photochemistry; D010785:Photophosphorylation / Q000187:drug effects; D010788:Photosynthesis / Q000187:drug effects*; D018724:Spinacia oleracea / Q000166:cytology / Q000187:drug effects / Q000528:radiation effects; D014025:Titanium / Q000494:pharmacology*; D014466:Ultraviolet Rays
C009495:titanium dioxide; D015086:2,6-Dichloroindophenol; D014025:Titanium