Raffia palm (Raphia hookeri) wine: Qualitative sugar profile, functional chemistry, and antidiabetic properties

The effects of short-term fermentation on the sugar quality, functional chemistry, antioxidant and antidiabetic properties of Raffia palm (Raphia hookeri) wine were investigated. Palm wine samples were subjected to open air fermentation for 24 and 48 h. The samples showed significant (p < 0.05) antioxidant activities with little or no differences between the unfermented and fermented samples. There was a dose-dependent inhibitory effect on α-glucosidase, α-amylase and intestinal glucose absorption with increasing fermentation time. Both non-fermented and 24 h fermentation led to increased muscle glucose uptake in a dose-dependent manner. ¹H NMR spectroscopy showed the presence of allose, cellobiose, d-tagatose, fructose, galactitol, gluconic acid, rhamnose, sucrose, xylose and β-N-acetylglucosamine in the samples. FTIR spectroscopy showed the presence of alcohols, phenols, 1° and 2° amines and aromatics functional groups in all samples. Fermentation led to the addition of the functional group, bend alkenes. These results suggested that un-fermented and fermented Raffia palm wine may have antioxidant and antidiabetic properties.