Exploring separation patterns and mechanisms of proanthocyanidins in grape seeds and pomace with diverse molecular weights, compositions, and structures

Xiaoyi Chen; Hong Song; Shubo Zhou; Chunlong Yuan; Junjun Li

doi:10.1016/j.fochx.2023.101008

Exploring separation patterns and mechanisms of proanthocyanidins in grape seeds and pomace with diverse molecular weights, compositions, and structures

Food Chem X. 2023 Nov 14:20:101008. doi: 10.1016/j.fochx.2023.101008. eCollection 2023 Dec 30.

Authors

Xiaoyi Chen¹, Hong Song¹, Shubo Zhou¹, Chunlong Yuan^{1

2}, Junjun Li¹

Affiliations

¹ College of Enology, Northwest A&F University, Yangling 712100, China.
² Ningxia Helan Mountain's East Foothill Wine Experiment and Demonstration Station of Northwest A&F University, Yongning, Ningxia 750104, China.

Abstract

The function of proanthocyanidins (PAs) relies on their structure and requires high-purity PAs. Though Sephadex LH-20 gel permeation chromatography (GPC) is expected to separate PAs based on structure, its usage rules and mechanisms remain unclear. This study delves into the PAs separation patterns on Sephadex LH-20, first confirming the purification mechanisms of PAs with various mean degrees of polymerization (DP) using the adsorption kinetic model. The study found that an increase in the molecular weight or mean DP of PAs results in decreased polarity, reduced hydrogen bonding actions, and intensified hydrophobic effect, causing delayed extraction of PAs on Sephadex LH-20, with galloylated PA as an exception, which was extracted first despite its high DP. Additionally, the principles for separating specific composition, such as monomers, dimers, etc., were evaluated. The study sheds light on enhancing the purification efficiency of PAs, thus advancing the precise separation technology of diverse proanthocyanidins.

Keywords: (+)-catechin (PubChem CID9064); (−)-epicatechin (PubChem CID72276); (−)-epicatechin gallate (PubChem CID107905); (−)-epigallocatechin gallate (PubChem CID65064); Adsorption kinetics; Proanthocyanidins; Reverse chromatography; Sephadex LH-20; procyanidin B1 (PubChem CID11250133); procyanidin B2 (PubChem CID122738).