Figure 2: Effects of various BG extracts on GLP-1 secretion in STC-1. After a 3 hr starvation in 10% FBS DMEM (low glucose), cells were treated with 0.2 % BSA DMEM (low glucose) containing (a) WE: water extract, EE: ethanol extract, or EAE: ethyl acetate extract; (b) WEL: large molecular weight fraction, >3 kD, of WE, WES: small molecular weight fraction, <3 kD, of WE, or Pf: P fraction, insulin-like peptide-rich fraction; (c) BGP-bi: crude bitter taste compounds extract for 1 hr. All data were calculated as GLP-1 secretion per cell and the secretion of vehicle-treated cells was taken as 1. The basal GLP-1 secretion of the vehicle-treated cells was 40~120 pM/well. Data are mean ± SD of 1~3 batches of experiments, with 1~3 for each treatment. * , ** , and *** denote significant difference compared to vehicle-treated cells analyzed by Student’s test with RCBD to adjust for the differences between separate batches of experiments.