Raw coffee based dietary supplements contain carboxyatractyligenin derivatives inhibiting mitochondrial adenine-nucleotide-translocase

Capsules, powders and tablets containing raw coffee extract are advertised to the consumer as antioxidant rich dietary supplements as part of a healthy diet. We isolated carboxyatractyligenin (4), 2-O-beta-D-glucopyranosyl carboxyatractyligenin (6) and 3'-O-beta-D-glucopyranosy1-2'-O-isovaleryl-2 beta-(2-desoxy-carboxyatractyligenin)-beta-D-glucopyranoside (8) from green coffee and found strong inhibitory effects on phosphorylating respiration in isolated mitochondria similar to the effects of the known phytotoxin carboxyatractyloside. LC-MS/MS analysis of commercial green coffee based dietary supplements revealed the occurrence of carboxyatractyligenin, 3'-O-beta-D-glucopyranosyl-2'-O-isovalery1-2 beta-(2-desoxy-carboxyatractyligenin)-beta-D-glucopyranoside, and 2-O-beta-D-glucopyranosyl carboxyatractyligenin in concentrations up to 4.0, 5.7, and 41.6 mu mol/g, respectively. These data might help to gain first insight into potential physiological side-effects of green coffee containing dietary supplement. (C) 2014 Elsevier Ltd. All rights reserved.