Step‐Gradient CCC Separation of Phenylpropanoid and Iridoid Glycosides from Roots of Stachytarpheta cayennensis (Rich.) Vahl

Abstract

Glycosylated phenylpropanoids and iridoids were isolated from the ethyl acetate extract from the roots of Stachytarpheta cayennensis by step gradient countercurrent chromatography (CCC). The chosen gradient utilized a stepwise increase of the butanol ratio in a normal phase separation, utilizing a biphasic EtOAc:BuOH:H₂O solvent system, 1:X:1 v/v/v, in four steps: A−X=0.05, B−X=0.2, C−X=0.5 and D−X=1.0. The sequential increase of BuOH in the organic phase of the CCC solvent system, and wash‐off of stationary phase allowed the isolation of 4 compounds identified as martinoside, isoverbascoside, verbascoside, ipolamiide, and two more iridoid glycosides. These compounds covered a wide span of polarities.

Keywords:

• Stachytarpheta cayennensis
• Verbenaceae
• Gradient elution
• Countercurrent chromatography

Acknowledgments

G. G. Leitão is especially indebted to CNPq and FAPERJ for financial support and the opportunity of presenting this paper at the 3rd International Countercurrent Chromatography Conference (CCC2004) at Tokyo, Japan, 2004. We are also thankful to CAPES for a student's scholarship.