Fractionation Protocol for the Isolation of Polypeptides from Plant Biomass

P Claeson; U Göransson; S Johansson; T Luijendijk; L Bohlin

doi:10.1021/np970342r

Fractionation Protocol for the Isolation of Polypeptides from Plant Biomass

J Nat Prod. 1998 Jan 23;61(1):77-81. doi: 10.1021/np970342r.

Authors

P Claeson¹, U Göransson, S Johansson, T Luijendijk, L Bohlin

Affiliation

¹ Division of Pharmacognosy, Department of Pharmacy, Biomedical Center, Uppsala University, Box 579, S-751 23 Uppsala, Sweden.

PMID: 9548831
DOI: 10.1021/np970342r

Abstract

A fractionation protocol for the isolation of a highly purified polypeptide fraction from plant biomass is described. The procedure dereplicates ubiquitous substance classes known to interfere with bioassays often used in natural product-based drug discovery programs. The protocol involves pre-extraction with dichloromethane, extraction with ethanol (50%), removal of tannins with polyamide, removal of low-molecular-weight components with size-exclusion chromatography over Sephadex G-10, and final removal of salts and polysaccharides with solid-phase extraction using reversed-phase cartridges. The method has been applied to the aerial parts of Viola arvensis, resulting in the isolation of a peptide fraction that on further separation yielded a novel 29-residue macrocyclic polypeptide named varv peptide A, cyclo(-TCVGGTCNTPGCSCSWPVCTRNGLPVCGE-).