Antioxidant Activity and Proanthocyanidin Profile of Selliguea feei Rhizomes

Molecules

Caili Fu¹  Hongyu Wang²  Wei Ling Ng²  Lixia Song² 

[1] College of Bioscience & Biotechnology, Fuzhou University, Fuzhou 350108, Fujian, China;Department of Chemistry, National University of Singapore, 3 Science Dr. 3, Singapore 117543, Singapore

关键词: Selliguea feei;    proanthocyanidins;    thiolysis;    antioxidant activity;   

DOI  :  10.3390/molecules18044282

来源: mdpi

【 摘 要 】

Proanthocyanidins from the rhizomes of Selliguea feei (PSFs) were solvent-extracted and fractionated by Sephadex LH-20 column chromatography to give a 2.42% isolated yield (dry matter basis). ¹H-NMR spectroscopy revealed the mean degree of polymerization (mDP) to be 2.6. ¹³C-NMR analysis showed typical signals for afzelechin/epiafzelechin units. Clear peaks at 76 ppm and 84 ppm indicated that both stereoisomers (afzelechin/epiafzelechin) are present. In agreement with the NMR spectra, the ESI-MS spectrum indicated that PSFs are mainly monomers to trimers consisting of afzelechin/epiafzelechin units with A-type and B-type interflavanyl linkages. A trimer was purified and identified as demethylated selligueain B. Thiolysis confirmed the structure and the thiolytic products, methyl 2-[(2R, 3R, 4S)-3,5,7-trihydroxy-2-(4-hydroxyphenyl)chroman-4-yl]acetate (1) and 4β-(carboxymethyl)sulphanylepiafzelechin-(2β→O→7,4β→8)-epiafzelechin methyl ester (2), were purified and characterized. Selligueain A, demethylated selligueain B, compounds 1 and 2 possess high antioxidant capacity at 1.18 × 10⁴, 1.16 × 10⁴, 0.95 × 10⁴ and 1.29 × 10⁴ µmol TE/g, respectively.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.