{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T11:38:05Z","timestamp":1789990685767,"version":"4.0.1"},"reference-count":40,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2017,10,18]],"date-time":"2017-10-18T00:00:00Z","timestamp":1508284800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Genistein, but not daidzein, binds to copper(II) with a 1:2 stoichiometry in ethanol and with a 1:1 stoichiometry in methanol, indicating chelation by the 5-phenol and the 4-keto group of the isoflavonoid as demonstrated by the Jobs method and UV-visible absorption spectroscopy. In ethanol, the stability constants had the value 1.12 \u00d7 1011 L2\u2219mol\u22122 for the 1:2 complex and in methanol 6.0 \u00d7 105 L\u2219mol\u22121 for the 1:1 complex at 25 \u00b0C. Binding was not detected in water, as confirmed by an upper limit for the 1:1 stability constant of K = 5 mol\u22121 L as calculated from the difference in solvation free energy of copper(II) between methanol and the more polar water. Solvent molecules compete with genistein as demonstrated in methanol where binding stoichiometry changes from 1:2 to 1:1 compared to ethanol and methanol\/chloroform (7\/3, v\/v). Genistein binding to copper(II) increases the scavenging rate of the stable, neutral 2,2-diphenyl-1-picrylhydrazyl radical by more than a factor of four, while only small effects were seen for the short-lived but more oxidizing \u03b2-carotene radical cation using laser flash photolysis. The increased efficiency of coordinated genistein is concluded to depend on kinetic rather than on thermodynamic factors, as confirmed by the small change in reduction potential of \u22120.016 V detected by cyclic voltammetry upon binding of genistein to copper(II) in methanol\/chloroform solutions.<\/jats:p>","DOI":"10.3390\/molecules22101757","type":"journal-article","created":{"date-parts":[[2017,10,18]],"date-time":"2017-10-18T11:10:00Z","timestamp":1508325000000},"page":"1757","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Genistein Binding to Copper(II)\u2014Solvent Dependence and Effects on Radical Scavenging"],"prefix":"10.3390","volume":"22","author":[{"given":"Jing","family":"Yang","sequence":"first","affiliation":[{"name":"Department of Chemistry, Renmin University of China, No. 59, ZhongGuanCun Street, Beijing 100872, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Xu","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Renmin University of China, No. 59, ZhongGuanCun Street, Beijing 100872, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6741-7295","authenticated-orcid":false,"given":"Hao-Yu","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Renmin University of China, No. 59, ZhongGuanCun Street, Beijing 100872, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1293-8413","authenticated-orcid":false,"given":"Rui-Min","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Renmin University of China, No. 59, ZhongGuanCun Street, Beijing 100872, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jian-Ping","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Renmin University of China, No. 59, ZhongGuanCun Street, Beijing 100872, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1734-5016","authenticated-orcid":false,"given":"Leif","family":"Skibsted","sequence":"additional","affiliation":[{"name":"Department of Food Science, University of Copenhagen, Rolighedsvej 30, DK-1058 Frederiksberg C, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1035","DOI":"10.1021\/np9904509","article-title":"Flavonoids as antioxidants","volume":"63","author":"Pietta","year":"2000","journal-title":"J. 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