Unravelling the Photoprotection Capacity of Resveratrol on Histidine Oxidation

Exposure to sun radiation causes great oxidative stress and activates a numerous of defense mechanisms in living systems, such as the synthesis of antioxidants. Resveratrol (RSV), a naturally occurring stilbene molecule, has antioxidant properties and is synthesized in large amounts when plants are under high oxidative stress. Likewise, under UV and visible radiation, biomolecules are oxidized, losing their physiological properties and, therefore, avoiding the harmful effects of solar radiation is crucial in order to preserve the functionality of cellular components. In proteins, one essential component that is often susceptible to degradation is the amino acid histidine (His), which can be modified via several oxidizing mechanisms. In this article, we evaluate the photoprotection capacity of RSV in photosensitized oxidation of His, which is initiated with a one-electron transfer reaction, yielding the His radical cation (His•+). The photoprotective properties of RSV are evaluated using kinetics analysis during steady-state irradiation and laser flash photolysis experiments. The experimental results reveal that the presence of RSV in the solution causes an evident decrease of the His consumption initial rates as a result of a reaction between His•+ and RSV that recovers the amino acid. In addition, we conclude that during its antioxidant action, RSV is consumed being a sacrificial antioxidant.

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Laser flash photolysis study on antioxidant properties of hydroxycinnamic acid derivatives

Radiation and Environmental Biophysics ◽

10.1007/s00411-006-0041-8 ◽

2006 ◽

Vol 45 (1) ◽

pp. 73-77 ◽

Cited By ~ 14

Author(s):

Hongping Zhu ◽

Hongwei Zhao ◽

Zhaoxia Zhang ◽

Wenfeng Wang ◽

Side Yao

Keyword(s):

Flash Photolysis ◽

Laser Flash Photolysis ◽

Antioxidant Properties ◽

Laser Flash ◽

Hydroxycinnamic Acid ◽

Hydroxycinnamic Acid Derivatives

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Silicon phthalocyanine-azobenzene-[60]fullerene light harvesting pentad: synthesis, characterization and electron transfer reaction studied by laser flash photolysis

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424613501046 ◽

2013 ◽

Vol 17 (11) ◽

pp. 1055-1063 ◽

Cited By ~ 6

Author(s):

Mohamed E. El-Khouly ◽

Jong-Hyung Kim ◽

Kwang-Yol Kay ◽

Shunichi Fukuzumi

Keyword(s):

Electron Transfer ◽

Transfer Reaction ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Light Harvesting ◽

Visible Spectrum ◽

Laser Flash ◽

Electron Transfer Reaction ◽

Strong Light ◽

Silicon Phthalocyanine

Electron-transfer reaction of the newly synthesized light harvesting pentad composed of silicon phthalocyanine (SiPc) that is connected with two fullerene C 60 and two azobenzene units to form SiPc -(azobenzene)2-( C 60)2 pentad has been studied by laser flash photolysis and other complementary techniques. This combination between SiPc , azobenzene and C 60 in the examined SiPc -(azobenzene)2-( C 60)2 pentad leads to strong light absorption over the whole visible spectrum. Photoexcitation of the pentad results in rapid formation of the charge-separated state by photoinduced electron transfer from the singlet-excited state of the SiPc moiety to the C 60 moiety. The charge-separated state has a lifetime of 2.50 ns in benzonitrile.

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Amino acid residues in Anabaena ferredoxin crucial to interaction with ferredoxin-NADP+ reductase: Site-directed mutagenesis and laser flash photolysis

Biochemistry ◽

10.1021/bi00087a013 ◽

1993 ◽

Vol 32 (36) ◽

pp. 9346-9354 ◽

Cited By ~ 78

Author(s):

J. K. Hurley ◽

Z. Salamon ◽

T. E. Meyer ◽

J. C. Fitch ◽

M. A. Cusanovich ◽

...

Keyword(s):

Amino Acid ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Laser Flash ◽

Site Directed Mutagenesis ◽

Directed Mutagenesis ◽

Amino Acid Residues

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Photoinduced Electron Transfer Reaction in Room Temperature Ionic Liquids: A Combined Laser Flash Photolysis and Fluorescence Study

The Journal of Physical Chemistry B ◽

10.1021/jp067481e ◽

2007 ◽

Vol 111 (8) ◽

pp. 1957-1962 ◽

Cited By ~ 80

Author(s):

Aniruddha Paul ◽

Anunay Samanta

Keyword(s):

Photoinduced Electron Transfer ◽

Room Temperature ◽

Transfer Reaction ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Laser Flash ◽

Electron Transfer Reaction ◽

Room Temperature Ionic Liquids ◽

Fluorescence Study ◽

Photoinduced Electron Transfer Reaction

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Intramolecular photoinduced electron transfer reactions of zinc(II) porphyrin dyads studied with a sub-ns time resolution

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424620500224 ◽

2020 ◽

Vol 24 (09) ◽

pp. 1099-1104

Author(s):

Kei Sakakibara ◽

Kenta Tomida ◽

Tatsuo Nakagawa ◽

Takeyoshi Yagyu ◽

Hideo D. Takagi ◽

...

Keyword(s):

Electron Transfer ◽

Time Resolution ◽

Photoinduced Electron Transfer ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Laser Flash ◽

Electron Transfer Reaction ◽

Transfer Reactions ◽

Electron Transfer Reactions ◽

Nanosecond Time Resolution

We report the dynamics of a intramolecular photoinduced electron transfer reaction of Zn(II)-porphyrin dyads that have a 2,2[Formula: see text]-bipyridine moiety at the periphery in the presence of Cu[Formula: see text] in methanol studied using laser flash photolysis with a sub-nanosecond time resolution. The photoinduced electron transfer reactions were observed from the excited [Formula: see text] and [Formula: see text] states of the Zn(II)-porphyrin to the Cu(II)-2,2[Formula: see text]-bipyridine moiety, and the structural dependence of the reactivity were discussed in terms of the distance between the electron donating and accepting centers.

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Photochemical Electron Transfer Between Methylene Blue and Quinones

Australian Journal of Chemistry ◽

10.1071/ch9940209 ◽

1994 ◽

Vol 47 (2) ◽

pp. 209 ◽

Cited By ~ 17

Author(s):

M Misran ◽

D Matthews ◽

P Valente ◽

A Hope

Keyword(s):

Methylene Blue ◽

Electron Transfer ◽

Flash Photolysis ◽

Laser Flash Photolysis ◽

Lipid Vesicles ◽

Laser Flash ◽

Electron Transfer Reaction ◽

Vitamin K1 ◽

Photochemical Oxidant ◽

Back Electron Transfer

Methylene Blue is a well known photochemical oxidant. In this paper we present results of cyclic voltammetry and laser flash photolysis experiments which demonstrate that Methylene Blue may function also as a photochemical reductant. Laser flash photolysis studies of Methylene Blue were carried out in aqueous solution at pH 10, in ethanol and in aqueous dispersions of lipid vesicles in the presence of benzoquinol , benzoquinone and the long-chain naphthoquinone Vitamin K1. Both the quinones and the quinol affected the transient of the decay of triplet Methylene Blue to its ground electronic state. The transients were biphasic and characteristic of an initial electron transfer reaction between triplet Methylene Blue and the quinone or quinol , followed by back electron transfer between the products. For Vitamin K1 and Methylene Blue in ethanol the back electron transfer was very slow (lifetime about 4 ms). This slow back electron transfer is favourable to the use of this system for energy storage via photosynthetic solar energy conversion.

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