In Vitro Screening of Potential Role of Green and Roasted Coffee Extracts in Type 2 Diabetes Management

This study evaluates the potential role of two extracts derived from green and roasted coffee in managing Type 2 Diabetes (T2D). The phytochemical analysis revealed that the roasted coffee extract (RCE) contains higher levels of flavonoids and tannins, while the green coffee extract (GCE) seems to be richer in phenolic acids. No differences in the antioxidant activity of both extracts were observed. The study demonstrated that GCE exhibits stronger prebiotic potential by significantly enhancing the growth of beneficial probiotic bacteria when compared to the untreated sample. Both extracts inhibited α-amylase and α-glucosidase enzymes, with RCE demonstrating a better performance than other commercial treatments for T2D. Glucose uptake assays on yeast cells demonstrated that both extracts enhance glucose transport, particularly at low glucose concentrations, reducing supernatant glucose levels by 60–80%. Notably, GCE maintained its effectiveness even at the highest glucose concentrations tested. These findings suggest that coffee extracts, particularly GCE, may be useful as nutraceuticals for potentially regulating glucose metabolism and gut microbiota in T2D management.