Phenolic antioxidants from Casimiroa edulis leaves

• Published in: Pharmaceutical biology Vol. 44; no. 4; pp. 258 - 262
• Main Authors: Awaad, A.S, El-Sayed, N.H, Maitland, D.J, Mabry, T.J
• Format: Journal Article
• Language: English
• Published: Lisse Informa UK Ltd 01.01.2006; Taylor & Francis; Swets & Zeitlinger
• Subjects: antioxidant activity; Antioxidants; Biological and medical sciences; Casimiroa edulis; chemical bonding; chemical constituents of plants; chemical structure; flavones; flavonoids; free radicals; General pharmacology; laboratory techniques; leaves; Medical sciences; medicinal plants; new flavones; Pharmacognosy. Homeopathy. Health food; Pharmacology. Drug treatments; phenolic compounds; quercetin; Rotaceae; rutin; spectroscopy; wild plants; free radicals; Flavones; Pharmacognosy; Rutaceae; Casimiroa edulis; Plant leaf; Antioxidant; Flavonoid; Free radical; Medicinal plant; Antioxidants; Polyphenol; Dicotyledones; Angiospermae; Plant origin; Phenols; Spermatophyta; new flavones; Rotaceae; flavonoids
• ISSN: 1388-0209; 1744-5116
• DOI: 10.1080/13880200600713899

Abstract In the present current, quercetin and its 3-O.-rutinoside, the ethyl acetate and ethanol extracts, and two new flavones from Casimiroa edulis. Llave et Lex (Rotaceae) were tested for their antioxidant activity via scavenging by the ABTS + [2,2′-azinobis(3-ethylbenzothiazolone-6-sulfonic acid)]free radical. Among all the tested fractions and compounds, the ethanol extract exhibited the strongest antioxidant activity followed by EtOAc extract, giving 842 and 712 µM Trolox equivalents/g dry weight, respectively. Moderate activities were detected for the other tested materials. The two new flavones were identified as 5-methoxy-6-hydroxyflavone and its 6-O.-β.-D-glucoside. The structure elucidation was based on UV, electrospray ionization mass spectrometry (ESIMS), 1H and 13C NMR, proton-proton correlation spectroscopy (1H-1H COSY), distortionless enhancement by polarization transfer (DEPT), heteronuclear single quantum coherence (HSQC), and heteronuclear multiple bond correlations spectrum (HMBC).