2-O-β-d-Glucopyranosyl-carboxyatractyligenin from Coffea L. inhibits adenine nucleotide translocase in isolated mitochondria but is quantitatively degraded during coffee roasting

2- O -β- d -Glucopyranosyl-carboxyatractyligenin isolated from raw coffee beans inhibits ATP-production in isolated mitochondria by blockage of adenine nucleotide translocase. UPLC-ToF-MS quantification revealed high levels of this phytochemical in lyophilized raw coffee extracts but complete degradation during coffee roasting. • Glucosides of atractyligenin derivatives were isolated from coffee. • Carboxyatractyligenin-glcp inhibits mitochondrial adenine nucleotide translocase. • A quantitation method was developed for atractyligenin glucoside derivatives. • Carboxyatractyligenin-glcp is degraded upon coffee roasting. Atractyloside ( 1 ) and carboxyatractyloside ( 2 ) are well-known inhibitors of the adenine nucleotide translocase (ANT) in mitochondria, thus effectively blocking oxidative phosphorylation. Structurally related derivatives atractyligenin ( 3 ), 2- O -β- d -glucopyranosyl-atractyligenin ( 4 ), 3′- O -β- d -glucopyranosyl-2′- O -isovaleryl-2β-(2-desoxy-atractyligenin)-β- d -glucopyranoside ( 5 ), and 2- O -β- d -glucopyranosyl-carboxyatractyligenin ( 6 ) were isolated from raw beans of Coffea L. and the impact of 1 – 6 on ANT activity was evaluated in isolated mitochondria. Among the coffee components, 6 significantly inhibited ANT activity leading to reduced respiration. Quantitative analysis in commercial coffees, experimental roastings of coffee, and model experiments using purified compound 6 consistently revealed a complete degradation during thermal treatment. In comparison, raw coffee extracts were found to contain high levels of 6 , which are therefore expected to be present in food products enriched with raw coffee extracts. This implies the necessity of analytically controlling the levels of 6 in raw coffee extracts when used as additives for food products.