Coumaroyl quinic acid derivatives and flavonoids from immature pear (Pyrus pyrifolia nakai) fruit

• Published in: Food science and biotechnology Vol. 22; no. 3; pp. 803 - 810
• Main Authors: Lee, Yu Geon, Cho, Jeong-Yong, Kim, Chan-Mi, Lee, Sang-Hyun, Kim, Wol-Soo, Jeon, Tae-Il, Park, Keun-Hyung, Moon, Jae-Hak
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2013; 한국식품과학회
• Subjects: Chemistry; Chemistry and Materials Science; Food Science; Nutrition; Pyrus pyrifolia; Research Article; 식품과학; immature pear fruit; Nakai; isorhamnetin glycoside; coumaric acid derivative; antioxidant activity
• ISSN: 1226-7708; 2092-6456
• DOI: 10.1007/s10068-013-0148-z

Fourteen compounds were isolated from 60% ethanol extracts of immature pear ( Pyrus pyrifolia Nakai cv. Chuhwangbae) fruit using Amberlite XAD-2 column HPLC with guided DPPH radical scavenging assay. Based on MS and NMR analysis, the isolated compounds were identified as 5- O-trans -caffeoyl quinic acid methyl ester ( 1 ), malaxinic acid ( 2 ), 5- O-trans-p -coumaroyl quinic acid methyl ester ( 3 ), 5- O-cis-p -coumaroyl quinic acid methyl ester ( 4 ), 5- O-trans-p -coumaroyl quinic acid ( 5 ), trans-p -coumaric acid ( 6 ), methyl cis-p -coumarate ( 7 ), methyl trans-p -coumarate ( 8 ), 3,5- O -dicaffeoyl quinic acid ( 9 ), (-)-epicatechin ( 10 ), (S)-(+)-2- cis -abscisic acid ( 11 ), isorhamnetin 3- O -β- d -galacto-pyranoside (12), isorhamnetin-3- O -β- d -glucopyranoside ( 13 ), and isorhamnetin 3- O -α- l -rhamnopyranosyl (1→6)- O -β- d -glucopyranoside ( 14 ). Six compounds ( 1, 2, 6, 9, 10 , and 13 ) were identified previously, but other compounds ( 3–5, 7, 8, 11, 12 , and 14 ) were isolated for the first time from pear.