Institute of Chemistry, São Paulo State University, Unesp, Francisco Degni Street, Araraquara-SP, Brazil.
Chirality. 2010 Aug;22(8):726-33. doi: 10.1002/chir.20824.
When catechins are found in plant extracts, they are almost always identified as catechin and/or epicatechin probably due to stereoselectivity of the enzymes involved in the biosynthesis of these substances. However, the lack of reports regarding to ent-catechin as well as ent-epicatechin does not necessarily mean that these compounds have not been produced. In fact, most of the previous reports used chromatographic conditions not suitable for such separation. This article describes a simple and reliable analytical HPLC-PAD-CD method for simultaneous determination of catechin diastereomers both in infusions and extracts from the leaves of Byrsonima species. The direct separation of catechin, ent-catechin, epicatechin, and ent-epicatechin was obtained in normal phase by HPLC-PAD-CD using Chiralcel OD-H as chiral stationary phase and n-hexane/ethanol with 0.1% of TFA as mobile phase.
当儿茶素存在于植物提取物中时，由于参与这些物质生物合成的酶的立体选择性，它们几乎总是被鉴定为儿茶素和/或表儿茶素。然而，缺乏有关表儿茶素和表儿茶素的报道并不一定意味着这些化合物没有被产生。事实上，大多数先前的报告使用的色谱条件不适合这种分离。本文描述了一种简单可靠的 HPLC-PAD-CD 分析方法，用于同时测定 Byrsonima 属叶的浸出液和提取物中儿茶素的非对映异构体。通过 HPLC-PAD-CD 使用 Chiralcel OD-H 作为手性固定相，正相直接分离儿茶素、表儿茶素、表儿茶素和表儿茶素，流动相为 n-己烷/乙醇，其中含有 0.1%的 TFA。
