{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T13:58:55Z","timestamp":1791381535144,"version":"4.3.3"},"reference-count":41,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,8,5]],"date-time":"2022-08-05T00:00:00Z","timestamp":1659657600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2020R1A2C1010724"],"award-info":[{"award-number":["NRF-2020R1A2C1010724"]}]},{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2021K2A9A1A01101863"],"award-info":[{"award-number":["NRF-2021K2A9A1A01101863"]}]},{"name":"National Research Foundation of Korea (NRF)","award":["NRF-2020R1A6A1A03038817"],"award-info":[{"award-number":["NRF-2020R1A6A1A03038817"]}]},{"name":"Ministry of Science and ICT","award":["NRF-2020R1A2C1010724"],"award-info":[{"award-number":["NRF-2020R1A2C1010724"]}]},{"name":"Ministry of Science and ICT","award":["NRF-2021K2A9A1A01101863"],"award-info":[{"award-number":["NRF-2021K2A9A1A01101863"]}]},{"name":"Ministry of Science and ICT","award":["NRF-2020R1A6A1A03038817"],"award-info":[{"award-number":["NRF-2020R1A6A1A03038817"]}]},{"name":"Ministry of Education","award":["NRF-2020R1A2C1010724"],"award-info":[{"award-number":["NRF-2020R1A2C1010724"]}]},{"name":"Ministry of Education","award":["NRF-2021K2A9A1A01101863"],"award-info":[{"award-number":["NRF-2021K2A9A1A01101863"]}]},{"name":"Ministry of Education","award":["NRF-2020R1A6A1A03038817"],"award-info":[{"award-number":["NRF-2020R1A6A1A03038817"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antioxidants"],"abstract":"<jats:p>Oxo-carotenoids containing conjugated carbonyl groups in their chains were designed to be more efficient superoxide radical scavengers than natural carotenoids, \u03b2-carotene and canthaxanthin. A practical chain-extension method for polyene dials (e.g., crocetin dial) was also proposed based on Horner\u2013Wadsworth\u2013Emmons olefination. Double aldol condensation between polyene dials and acetophenones with ring substituents produced oxo-carotenoids with substituted benzene rings. The antioxidant activity of oxo-carotenoids was measured using DPPH (radical) and ABTS (cationic radical) scavenging assays and compared with the analysis with the superoxide (anionic radical) probe. An effective conjugation length by carbon\u2013carbon double bonds is important to provide superior antioxidant activity for oxo-carotenoids, regardless of the type of radical probe used in the assay. Increasing electron density is favorable to strong antioxidant activity in DPPH, and the phenol group is favored in ABTS, whereas electron deficient oxo-carotenoids are very potent in the superoxide radical assay. All oxo-carotenoids exhibited 105~151% better superoxide radical scavenging activity compared to beta-carotene (100%), whereas 38~155% in DPPH and 16~96% in ABTS radical scavenging activities were observed.<\/jats:p>","DOI":"10.3390\/antiox11081525","type":"journal-article","created":{"date-parts":[[2022,8,7]],"date-time":"2022-08-07T21:03:50Z","timestamp":1659906230000},"page":"1525","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Oxo-Carotenoids as Efficient Superoxide Radical Scavengers"],"prefix":"10.3390","volume":"11","author":[{"given":"Gaosheng","family":"Shi","sequence":"first","affiliation":[{"name":"Department of Energy Science and Technology, Myongji University, Myongji-Ro 116, Yongin 17058, Gyeonggi-Do, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hyein","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Myongji University, Myongji-Ro 116, Yongin 17058, Gyeonggi-Do, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sangho","family":"Koo","sequence":"additional","affiliation":[{"name":"Department of Energy Science and Technology, Myongji University, Myongji-Ro 116, Yongin 17058, Gyeonggi-Do, Korea"},{"name":"Department of Chemistry, Myongji University, Myongji-Ro 116, Yongin 17058, Gyeonggi-Do, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"561","DOI":"10.1146\/annurev.nu.13.070193.003021","article-title":"Actions of Carotenoids in Biological Systems","volume":"13","author":"Krinsky","year":"1993","journal-title":"Annu. 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