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

Inhibition of the formation of amyloid-like fibrils with spices, especially cloves

During the study of inhibition of amyloid fibril formation, α-chymotrypsin protein was developed in 55% ethanol at pH 7.0. We investigated the inhibitory effect of different spices on amyloid fibril formation using turbidity measurements and Congo red binding assays. We found that all spices except the black pepper and caraway seed prevented fibril formation. The highest inhibition was measured with the clove, which reduced the amount of aggregates by 90%. We studied the inhibitory effect of the cloves at different concentrations on aggregation, it was found that the inhibitory activity of clove is dependent on concentration. We have measured the total phenolic content of the spice extracts too. Based on all these findings we have come to the following conclusion: Our results indicate that spices can contain other compounds too – not only phenolic compounds – which influence the formation of amyloid fibrils, and the effectiveness of various phenolic compounds are different