Biomolecular-chemical screening a novel screening approach for the discovery of biologically active secondary metabolites II. Application studies with pure metabolites

The novel screening strategy called "biomolecular-chemical screening'' comb ines the advantages of the chemical screening approach-the analysis of the chromatographic and chemical behaviour of secondary metabolites on TLC plat es-with binding studies of these molecules with bio-macromolecules like DNA . This approach was advantageously used to detect the interaction of pure c ompounds with DNA. In order to prove the reliability of the biomolecular-ch emical screening and to examine DNA-binding properties, 470 pure secondary metabolites were analysed by this method. Besides the confirmation of alrea dy known binders with the TLC-based method, for a number of natural product s DNA-binding properties were discovered for the first time. In consequence , binding of pure compounds can be measured by 1D TLC in a reliable and eas y manner, in which DNA is applied together with the test compound at the st arting spot. Analysis is performed via differences in Rf-values in comparis on to a reference chromatogram without DNA.