Evaluation and selection of optimal solvent and solvent combinations in thin-Iayer chromatography of flavonoids and of phenolic acids of Zizyphus jujuba MilI.

A series of simple mathematical techniques for the evaluation of solvents and solvent combinations in thin-layer chromatography have been investigated. The classification has been carried out using the numerical taxonomy techniques and information content derived from Shannon's equation. The methods have been applied to an RF data set of flavonoids and phenolic acids identified in the methanolic extract of Zizyphus jujuba MilI. The most suitable chromatographic systems for the separation and future isolation of flavonoids and phenolic acids from Zizyphus jujuba Mill. are : ethyl acetate : formic acid : acetic acid : water, 100 : 11 : 11 : 27, and ethyl acetate : formic acid : water, 8 : 1 : 1