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Updated: Feb 4, 2026

Isolation and Biophysical Study of Fruit Cuticles
Published on: March 30, 2012
Isolation of five proanthocyanidins from pear (Pyrus pyrifolia Nakai) fruit peels
Da Eun Jeong1, Jeong-Yong Cho1, Yu Geon Lee1
1Department of Food Science and Technology, Chonnam National University, BK21 Plus Program, Gwangju, Jeonnam 61186 Korea.
Abstract:
Five proanthocyanidins, two B-type dimers and three A-type trimers, were purified and isolated from the fruit peels of Pyrus pyrifolia Nakai cv. Chuhwangbae. The isolated compounds were identified as (-)-epicatechin gallate-(4β → 8)-(-)-epicatechin (Hahashi et al. in Ann Biol Res 3:3200-3207, 2012), (-)-epicatechin-(4β → 8)-(-)-epicatechin (procyanidin B2) (Tanrioven and Eksi in Food Chem 93:89-93, 2005), (-)-epicatechin-(4β → 8, 2β → O-7)-(-)-epicatechin-(4β → 8)-(-)-epicatechin (cinnamtannins B1) (Salta et al. in J. Fun. Food 2: 153-157, 2010), (-)-epicatechin-(4β → 8)-(-)-epicatechin-(4β → 8, 2β → O-7)-(-)-epicatechin (aesculitannin A) (Challice and Westwood in Phytochemistry 11: 37-44, 1972), and (-)-epicatechin-(4β → 6)-(-)-epicatechin-(4β → 8, 2β → O→7)-(-)-epicatechin (Es-Safi et al. in J Agric Food Chem 54: 6969-6977, 2006). Their structures were determined by nuclear magnetic resonance and mass spectrometry. The three A-type proanthocyanidin trimers were identified for the first time from pear.
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