C. medica cv Diamante peel chemical composition and influence on glucose homeostasis and metabolic parameters

This study evaluated the in vitro inhibition of carbohydrate-hydrolysing enzymes, the stimulation of insulin secretion, and the in vivo metabolic effects in mice of Citrus medica L. cv Diamante peel extract. The quantitative analysis of selected phytochemicals were determined to investigate their relationship with the biological activities. Citrus extract exhibited an inhibitory activity against both α-amylase and α-glucosidase with IC50 values of 258.7 and 263.2 μg/ml, respectively. Measurements of the effects of peel extract on the mouse insulinoma MIN6 β-cells indicated that it did exert direct stimulatory effects on the exocytotic release of insulin in a concentration-dependent manner. The supplementation of the C. medica cv Diamante was able to reduce plasma glucose (GLU) concentration and lowered the levels of plasma cholesterol (COL) and triglycerides (TG). The obtained results underline the potential health benefits as a result of consuming C. medica cv Diamante and suggest that it could be used as new potential source with functional properties for food or nutraceutical products.