EFFECT OF DIGITALIS-LANATA MATRIX COMPOSITION ON THE LANATOSIDE-C PARTITION-COEFFICIENT AND ITS CONSEQUENCE ON ROTATION LOCULAR COUNTERCURRENT CHROMATOGRAPHY EFFICIENCY

Lanatoside C standard samples had their partition coefficients (K) det ermined in dichloromethane-methanol-water (4:4:3), (5:6:4) and (7:13:8 ), by the shake flask method and the obtained values were similar. On the other hand, K for lanatoside C accomplished by calculation from ro tation locular counter-current chromatography (RLCC) traces of Digital is lanata pre-purified extracts, as well as by the shake flask method, in the same solvent systems, showed a significant variation. Such var iation was attributed to differences in the pre-purification procedure s for D. lanata extract, which resulted in starting materials for RLCC with very distinct cardenolide profiles, reflecting, thus, in the K v alues for lanatoside C and, consequently, in the lanatoside C purity a t the end of the chromatographic process. (C) 1998 Elsevier Science B. V. All rights reserved.