Bioaccessibility of Salvia pratensis L. phenolic compounds during in vitro gastrointestinal digestion

Abstract

This study aimed to determine the phenolic profile of the aerial part (SPA) and root (SPR) methanol extracts of Salvia pratensis L. and changes in the concentration of some identified compounds in these extracts during in vitro digestion process. A standardized static in vitro digestion method [1] was applied to simulate the oral, gastric, and intestinal phases of digestion of extracts followed by LC/MC analysis [2] in each phase of digestion. Using the UHPLC–MS4 Orbitrap analysis, 67 phenolic compounds were detected in SPA and SPR extracts. Among them, a total of 20 phenolic compounds were quantified in SPA, while 18 were quantified in SPR by UHPLC-DAD/(−)HESI-MS/MS analysis. The most dominant components in both extracts were rosmarinic and caffeic acids, whereas salvianolic acids A and B were found in high concentrations in the SPR extract. During in vitro gastrointestinal digestion of extracts, the content of total phenolics and flavonoids, as well as the antioxidant activity of extracts have not significantly changed compared with values determined initially. The results showed reduced bioaccessibility of rosmarinic acid in SPA and SPR, as well as salvianolic acid A in SPR during the simulated digestion process. However, digestion conditions did not affect the bioaccessibility of protocatechuic and p-hydroxybenzoic acid, while the concentration of caffeic acid increased during the intestinal phase of digestion. Considering the high diversity of phenolic compounds identified in extracts and high concentrations of some of the identified phenolic acids, S. pratensis may be used as a good alternative to the common sage.