title: Quantitative studies on structure-ORAC relationships of anthocyanins from eggplant and radish using 3D-QSAR.
abstract: The 3-dimensional quantitative structure activity relationship (3D-QSAR) models were established from 21 anthocyanins based on their oxygen radical absorbing capacity (ORAC) and were applied to predict anthocyanins in eggplant and radish for their ORAC values. The cross-validated q(2)=0.857/0.729, non-cross-validated r(2) = 0.958/0.856, standard error of estimate = 0.153/0.134, and F = 73.267/19.247 were for the best QSAR (CoMFA/CoMSIA) models, where the correlation coefficient r(2)pred = 0.998/0.997 (>0.6) indicated a high predictive ability for each. Additionally, the contour map results suggested that structural characteristics of anthocyanins favourable for the high ORAC. Four anthocyanins from eggplant and radish have been screened based on the QSAR models. Pelargonidin-3-[(6''-p-coumaroyl)-glucosyl(2 → 1)glucoside]-5-(6''-malonyl)-glucoside, delphinidin-3-rutinoside-5-glucoside, and delphinidin-3-[(4''-p-coumaroyl)-rhamnosyl(1 → 6)glucoside]-5-glucoside potential with high ORAC based the QSAR models were isolated and also confirmed for their relative high antioxidant ability, which might attribute to the bulky and/or electron-donating substituent at the 3-position in the C ring or/and hydrogen bond donor group/electron donating group on the R1 position in the B ring.
authors.affiliation: Research Center for Food Safety and Nutrition, Key Lab of Urban Agriculture (South), Bor S. LUH Food Safety Research Center, School of Agriculture & Biology, Shanghai Jiao Tong University, Shanghai 200240, China. Electronic address: pjcolumbus@gmail.com.
authors.forename: Pu
authors.initials: P
authors.lastname: Jing
authors.forename: Shujuan
authors.initials: S
authors.lastname: Zhao
authors.forename: Siyu
authors.initials: S
authors.lastname: Ruan
authors.forename: Zhongquan
authors.initials: Z
authors.lastname: Sui
authors.forename: Lihong
authors.initials: L
authors.lastname: Chen
authors.forename: Linlei
authors.initials: L
authors.lastname: Jiang
authors.forename: Bingjun
authors.initials: B
authors.lastname: Qian
mesh_terms: D000872:Anthocyanins / Q000737:chemistry* / Q000494:pharmacology; D006860:Hydrogen Bonding; D021621:Imaging, Three-Dimensional; D021281:Quantitative Structure-Activity Relationship; D031224:Raphanus / Q000737:chemistry*; D032323:Solanum melongena / Q000737:chemistry*
chemical_list: D000872:Anthocyanins
keywords: 3-dimensional quantitative structure activity relationship; 3D-QSAR; Anthocyanins; CoMFA; CoMSIA; LOO; Leave-One-Out; ORAC; Oxygen radical; Structure; TEAC; comparative molecular field analysis; molecular similarity indices analysis; oxygen radical absorbing capacity; trolox equivalent antioxidant capacity