A method for the rapid discovery of naturally occurring products by proteins immobilized on magnetic beads and reverse affinity chromatography.

A highly efficient screening method for naturally occurring products that bind to a specific target protein was demonstrated by using hVDR magnetic beads. The native ligand 1alpha,25(OH)2 VD3 (1) was selectively bound by hVDR magnetic beads when present in a mixture of natural compounds. Furthermore, this method was shown to be applicable to the identification of natural products that interact with a specific protein immobilized on the beads from an extract of a natural resource. Two new natural compounds were isolated by this method. This approach will be helpful for the discovery of novel, naturally occurring products that bind to specific target proteins. This method has the further advantages that it can identify the HPLC peak corresponding to the target compound for isolation, as well as provide important UV, CD, or MS profile information.