Simultaneous determination of the inhibitory potency of herbal extracts on the activity of six major cytochrome P450 enzymes using liquid chromatography/mass spectrometry and automated online extraction

Publisher Website
Google Scholar
Abstract
Here we describe a liquid chromatography/mass spectrometry (LC/MS) method with automated online extraction (LC/LC/MS) to simultaneously determine the in vitro inhibitory potency of herbal extracts on six major human drug‐metabolising cytochrome P450 enzymes. Substrates were incubated with a commercially available mixture of CYP1A2/2C8/2C9/2C19/2D6 and 3A4 from baculovirus‐infected insect cells and the resulting metabolites were quantified with LC/LC/MS using electrospray ionisation in the selected ion monitoring mode. Consistent inhibitory activities were obtained for known inhibitors and plant extracts using the enzyme/substrate cocktail and the individual enzymes/substrates. Popular herbal remedies including devil's claw root (Harpagophytum procumbens), feverfew herb (Tanacetum parthenium), fo‐ti root (Polygonum multiflorum), kava‐kava root (Piper methysticum), peppermint oil (Mentha piperita), eucalyptus oil (Eucalyptus globulus), red clover blossom (Trifoliumpratense) and grapefruit juice (GJ; Citrus paradisi) could be identified as inhibitors of the applied CYP enzymes with IC50 values between 20 and 1000 μg/mL. Copyright © 2004 John Wiley & Sons, Ltd.

This publication has 30 references indexed in Scilit: