Coffee extracts effectively inhibit the formation of α-chymotrypsin amyloid-like fibrils in aqueous ethanol in vitro.

In this study, an in vitro α-chymotrypsin aggregation model was used to demonstrate that certain extracts of commercial coffees effectively inhibit protein aggregation in 55% ethanol at pH 7.0. To detect the anti-amyloidogenic effect of the various coffee extracts, turbidity measurements and Congo red binding assays were performed as well as the determination of the total polyphenol content of the extracts. The greatest fibril formation inhibitory effect was exerted by the Eduscho coffee extract, which contained also the most of the phenolic compounds. The Eduscho coffee extract inhibited the fibrillation of the α-chymotrypsin dose dependently. Coffee extracts are effective anti-aggregation agents, and their beneficial effects strongly correlate with the total phenolic content.