scholarly journals Interactions of dietary carotenoids with singlet oxygen (1O2) and free radicals: potential effects for human health.

2012 ◽  
Vol 59 (1) ◽  
Author(s):  
Fritz Böhm ◽  
Ruth Edge ◽  
T George Truscott
Keyword(s):  
Free Radicals ◽  
Singlet Oxygen ◽  
Skin Protection ◽  
Oxygen Quenching ◽  
Time Resolved ◽  
Photosynthetic Organisms ◽  
Singlet Oxygen Quenching ◽  
Protection Mechanisms ◽  
Anti Oxidant ◽  
Β Carotene

The dietary carotenoids provide photoprotection to photosynthetic organisms, the eye and the skin. The protection mechanisms involve both quenching of singlet oxygen and of damaging free radicals. The mechanisms for singlet oxygen quenching and protection against free radicals are quite different - indeed, under some conditions, quenching of free radicals can lead to a switch from a beneficial anti-oxidant process to damaging pro-oxidative situation. Furthermore, while skin protection involves β-carotene or lycopene from a tomato-rich diet, protection of the macula involves the hydroxyl-carotenoids (xanthophylls) zeaxanthin and lutein. Time resolved studies of singlet oxygen and free radicals and their interaction with carotenoids via pulsed laser and fast electron spectroscopy (pulse radiolysis) and the possible involvement of amino acids are discussed and used to (1) speculate on the anti- and pro-oxidative mechanisms, (2) determine the most efficient singlet oxygen quencher and (3) demonstrate the benefits to photoprotection of the eye from the xanthophylls rather than from hydrocarbon carotenoids such as β-carotene.

Carotenoids, tocopherols and thiols as biological singlet molecular oxygen quenchers

1990 ◽  
Vol 18 (6) ◽  
pp. 1054-1056 ◽  
Author(s):  
PAOLO Di MASCIO ◽  
THOMAS P. A. DEVASAGAYAM ◽  
STEPHAN KAISER ◽  
HELMUT SIES
Keyword(s):  
Singlet Oxygen ◽  
Molecular Oxygen ◽  
Rate Constants ◽  
Protective Action ◽  
Biological Tissues ◽  
Oxygen Quenching ◽  
Quenching Rate ◽  
Singlet Molecular Oxygen ◽  
Singlet Oxygen Quenching ◽  
Β Carotene

Singlet molecular oxygen (1O2) has been shown to be generated in biological systems and is capable of damaging proteins, lipids and DNA. The ability of some biological antioxidants to quench 1O2 was studied by using singlet oxygen generated by the thermodissociation of the endoperoxide of 3,3′-(1,4-naphthylidene) dipropionate (NDPO2). The carotenoid lycopene was the most efficient 1O2 quencher (kq + kr = 31 × 109m-1s-1). Tocopherols and thiols were less effective. The singlet oxygen quenching ability decreased in the following order: lycopene, γ-carotene, astaxanthin, canthaxanthin, α-carotene, β-carotene, bixin, zeaxanthin, lutein, bilirubin, biliverdin, tocopherols and thiols. However, the compounds with low quenching rate constants occur at higher levels in biological tissues. Thus, carotenoids and tocopherols may contribute almost equally to the protection of tissues against the deleterious effects of 1O2. The quenching abilities of carotenoids and tocopherols were mainly due to physical quenching. In case of some thiols chemical quenching also plays a significant role. Carotenoids and tocopherols have been reported to exert a protective action against some types of cancer.

Singlet oxygen quenching by trolox C in aqueous micelle solutions

2009 ◽  
Vol 97 (3) ◽  
pp. 132-137 ◽  
Author(s):  
Keishi Ohara ◽  
Kaori Kikuchi ◽  
Takashi Origuchi ◽  
Shin-ichi Nagaoka
Keyword(s):  
Singlet Oxygen ◽  
Oxygen Quenching ◽  
Singlet Oxygen Quenching ◽  
Trolox C

scholarly journals Singlet Oxygen Quenching by Phenylamides and their Parent Compounds

2007 ◽  
Vol 62 (11-12) ◽  
pp. 833-838 ◽  
Author(s):  
Violeta B. Velikova ◽  
Aglika M. Edreva ◽  
Tsonko D. Tsonev ◽  
Hamlyn G. Jones
Keyword(s):  
Singlet Oxygen ◽  
Hydroxycinnamic Acids ◽  
Oxygen Quenching ◽  
Amino Groups ◽  
Plant Metabolites ◽  
Antioxidant Defence ◽  
Enzymatic Antioxidant ◽  
Singlet Oxygen Quenching ◽  
First Time ◽  
Photosynthetic Centers

This paper demonstrates for the first time that plant metabolites of the phenylamide type, conjugates of putrescine with hydroxycinnamic acids (p-coumaric, caffeic and ferulic), possess 1O2 quenching properties. Data were obtained confirming that their acidic parent compounds were also able to quench 1O2, as did polyamines (putrescine, spermidine and spermine), and that this ability depends on the number of amino groups. Potentiation of the 1O2 quenching ability of the conjugates relative to both parent components was established. The importance of polyamines and phenylamides in the plant non-enzymatic antioxidant defence at sites of intensive 1O2 generation, such as the photosynthetic centers, was suggested.

scholarly journals Basic Investigations of Singlet Oxygen Detection Systems with ESR for the Measurement of Singlet Oxygen Quenching Activities

2020 ◽  
Vol 68 (2) ◽  
pp. 150-154 ◽  
Author(s):  
Tokuko Takajo ◽  
Yoshinori Kurihara ◽  
Kodai Iwase ◽  
Daiki Miyake ◽  
Kazunori Tsuchida ◽  
...  
Keyword(s):  
Singlet Oxygen ◽  
Oxygen Quenching ◽  
Detection Systems ◽  
Oxygen Detection ◽  
Singlet Oxygen Quenching
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