Preparation of bioactive amide compounds from black pepper by countercurrent chromatography and preparative HPLC

Amide compounds are the major bioactive substances in black pepper. Black pepper extracts were fractionated by high-speed countercurrent chromatography resulting in three compounds: dehydropipernonaline, piperine and (2E,4E,12Z)-N-isobutyl-octadecatrienamide, and four fractions which were separated by preparative HPLC to yield ten purified compounds: retrofractamide-A, (2E,4E)-N-isobutyl-decadienamide, retrofractamide-C, piperoleine A, dehydropiperoleine A, retrofractamide-B, piperoleine B, pipernonaline, pipercyclobutanamides A and (2E,4E,14Z)-N-isobutyleicosa-2,4,14-trienamide as identified by ESI-MS and NMR analysis. The results of the present study indicated that HSCCC is an effective technique for the preparation of bioactive amide compounds from black pepper.

► A good solvent system of HSCCC was selected to fractionate black pepper extract. ► HSCCC separation resulted in three individual amide compounds with hundred-mg scale. ► 13 individual amide compounds were harvested from HSCCC and HPLC separation.