Assessment of the antioxidant activities of representative optical and geometric isomers of astaxanthin against singlet oxygen in solution by a spectroscopic approach. (30th November 2022)

• Record Type: Journal Article
• Authors: Zheng, Xinxin; Huang, Qing
• Is Part Of: Food chemistry. Volume 395(2022)
• Publication Date: 2022-11-30
• Subjects: Astaxanthin (AST) -- Isomers -- Antioxidant -- Singlet oxygen (1O2) -- Quenching rate -- Photosensitizer; 3S, 3′S astaxanthin (PubChem CID: 5368397) -- 3R, 3′R astaxanthin (PubChem CID: 12358421) -- 3R, 3′S astaxanthin (PubChem CID: 12358422) -- 13-cis-astaxanthin (PubChem CID: 91827159) -- All-trans-astaxanthin (PubChem CID: 5281224) -- Vitamin E (PubChem CID: 14985) -- Methylene blue (MB) (PubChem CID: 6099) -- 1, 3-diphenylisobenzofuran (DPBF) (PubChem CID: 21649).; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.133584
• Languages: English
• ISSNs: 0308-8146

Abstract

Graphic abstract: Highlights: Astaxanthin isomer antioxidant activities against 1 O2 can be assessed by using DPBF. The astaxanthin 1 O2 quenching capacity is three orders of magnitude greater than that of vitamin E. The 1 O2 quenching capacities of the optical isomers of all- trans- astaxanthin are identical. The cis -astaxanthin 1 O2 quenching capacity is greater than that of all- trans- astaxanthin. Abstract: Astaxanthin (AST) is a natural antioxidant and has been widely applied as a food supplement. While astaxanthin has many isomers, there are few studies comparing its physicochemical properties. In this work, we were concerned about their antioxidant activities against external oxidative stresses, and specifically, the singlet oxygen ( 1 O2 ) quenching capacities of the representative optical and geometric isomers of astaxanthin were examined. Methylene blue (MB) was used as the photosensitizer to produce 1 O2, and 1, 3-diphenylisobenzofuran (DPBF) was used to probe 1 O2 . Our results showed that the 1 O2 quenching capacities of the optical isomers, including 3 S, 3 ′S, 3 R, 3 ′S, and 3 R, 3 ′R all- trans -astaxanthin, are identical. In contrast, the 1 O2 quenching capacity of cis -astaxanthin is higher than that of all- trans -astaxanthin. As such, this work provides an effective spectroscopic approach to assessing the antioxidant activities of various forms of astaxanthin against singlet oxygen, and demonstrates the remarkable difference among the geometric isomers.