VANILLIN-HCI METHOD FOR CONDENSED TANNINS - EFFECT OF ORGANIC-SOLVENTS USED FOR EXTRACTION OF TANNINS
VANILLIN-HCI METHOD FOR CONDENSED TANNINS - EFFECT OF ORGANIC-SOLVENTS USED FOR EXTRACTION OF TANNINS
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DOI：
10.1007/bf00984996
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发表时间：
1993-04-01
影响因子：
2.3
通讯作者：
BECKER, K
中科院分区：
文献类型：
--
作者：
MAKKAR, HPS;BECKER, K
单宁通常使用水性有机溶剂（主要是甲醇和丙酮）提取。含有儿茶素或单宁的样品中存在不同浓度的甲醇并不会改变它们的反应动力学，但吸光度取决于样品中甲醇的量；甲醇含量越高，吸光度越高。丙酮与酸化香草醛反应产生波长为 548 nm 的色原，这会在缩合单宁的测定中产生很大的误差。在丙酮存在下，儿茶素和单宁的反应时间进程不同，这取决于丙酮浓度和反应温度。介绍了儿茶素和单宁的反应条件，使其能够在丙酮存在下进行测量。
Tannins are generally extracted using aqueous organic solvents, mainly methanol and acetone. The presence of various concentrations of methanol in the sample containing catechin or tannins did not alter the kinetics of their reaction, but the absorbance depended on the amount of methanol in the sample; the higher the methanol, the higher was the absorbance. Acetone reacted with acidified vanillin to produce a chromogen with lambda(max) at 548 nm, which produce a substantial error in the determination of condensed tannins. In the presence of acetone, the time courses of the reaction for catechin and tannins were different, which depended on the acetone concentration and the reaction temperature. Reaction conditions for catechin and tannins that enable their measurement in the presence of acetone are presented.