摘要
The interactions of carotenoids with NO·_ 2 were investigated by pulse radiolysis. Optical traces show bleaching of the ground-state absorption of β-carotene, zeaxanthin and canthaxanthin at 450 nm, and bixin at 460—510 nm. The transient absorption spectrum shows that the positive absorption attributed to the formation of carotenoid addition radicals cannot be observed in the range of 600—700 nm. It is suggested that carotenoids undergo more readily electron transfer with NO·_ 2 to yield the carotenoid radical cations. The rate constants for the reaction of β-carotene, zeaxanthin, bixin and canthaxanthin with NO·_ 2 obtained are 1.6×10 8, 2.41×10 8, 5.41×10 7 and 1.75×10 7 mol/(L -1·s -1), respectively.
The interactions of carotenoids with NO2^＊ were investigated by pulse radiolysis. Optical traces show bleaching of the ground-state absorption of β-carotene, zeaxanthin and canthaxanthin at 450 nm, and bixin at 460--510 nm. The transient absorption spectrum shows that the positive absorption attributed to the formation of carotenoid addition radicals cannot be observed in the range of 600--700 nm. It is suggested that carotenoids undergo more readily electron transfer with NO2^＊ to yield the carotenoid radical cations. The rate constants for the reaction of β-carotene, zeaxanthin, bixin and canthaxanthin with NO2^＊ obtained are 1.6 ×10^8, 2. 41× 10^8, 5.41 × 10^7 and 1.75 × 10^7 mol/（ L^-1·s^-1 ）, respectively.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2006年第3期556-558,共3页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:30470423)资助.
