Anthocyanins from purple corn activate free fatty acid-receptor 1 and glucokinase enhancing in vitro insulin secretion and hepatic glucose uptake
A) Quantification of anthocyanins present in PCW. The results are expressed as the mean ± SD of three independent determinations. B) Representative chromatogram of purple corn pericarp water extract (PCW) at 520 nm showing the different anthocyanins (ANC) identified as follows: 1 –condensed form of catechin-(4,8)-cyanidin-3,5-diglucoside; 2 –cyanidin-3-O-glucoside; 3—pelargonidin-3-O-glucoside; 4 –peonidin-3-O-glucoside; 5 –cyanidin-3-(6’-malonylglucoside); 6—pelargonidin-3-(6’-malonylglucoside); 7—peonidin-3-(6’-malonylglucoside). HPLC chromatogram of C) the semi-purified condensed form and D) semi-purified cyanidin-3-O-glucoside, isolated from PCW. Representative MS2 spectra of E) the semi-purified condensed form, and F) the semi-purified cyanidin-3-O-glucoside, showing the fragmentation pattern and structures of the compounds isolated from PCW.