Bioaccessibility and inhibitory effects on digestive enzymes of carnosic acid in sage and rosemary.
In this study, the aim was to determine the bioaccessibilities of carnosic acid in sage and rosemary and in vitro inhibitory effects of these samples on lipid and starch digestive enzymes by evaluating the lipase, α-amylase and α-glucosidase enzyme inhibition activities. The content of carnosic acid in rosemary (18.72 ± 0.33 mg/g) was found to be higher than that content of that in sage (3.76 ± 0.13 mg/g) (p < 0.05). The carnosic acid bioaccessibilities were found as 45.10 ± 1.88% and 38.32 ± 0.21% in sage and rosemary, respectively. The tested sage and rosemary showed inhibitory activity against α-glucosidase (Concentration of inhibitor required to produce a 50% inhibition of the initial rate of reaction - IC50 88.49 ± 2.35, 76.80 ± 1.68 μg/mL, respectively), α-amylase (IC50 107.65 ± 12.64, 95.65 ± 2.73 μg/mL, respectively) and lipase (IC50 6.20 ± 0.63, 4.31 ± 0.62 μg/mL, respectively). Furthermore, to the best of our knowledge, this is the first work that carnosic acid standard equivalent inhibition capacities (CAEIC50) for these food samples were determined and these values were in agreement with the IC50 values. These results show that sage and rosemary are potent inhibitors of lipase, α-amylase and α-glucosidase digestive enzymes.