Evaluation of fatty acid composition and antimicrobial activity of supercritical fluid extract of Rubus ulmifolius Schott fruits.

In this study, we continue our research on Rubus ulmifolius Schott extracts obtained by supercritical fluid extraction (SFE) using CO2 as solvent. Extraction experiments were carried out at pressures of 300 bar and a temperature of 40 °C, SFE [300:40], on mature fruits of R. ulmifolius. The fatty acid (FA) profile of extracts was assessed by reversed-phase HPLC-DAD/ELSD analysis. The most represented fatty acids in the extract were linoleic acid (386 mg/g), oleic acid (210 mg/g), linolenic acid (112 mg/g), palmitic acid (48 mg/g), and stearic acid (40 mg/g). SFE extraction showed a total FA amount of 795.8 mg/g of dry weight. The chemical and biological characteristics of this extract were compared with those obtained with different extraction methods. Following the diffusion-susceptibility test, three fruit extracts, SFE [300:40], Sx, and MEtOH, didn't show an inhibition profile against Streptococcus mutans. Kirby-Bauer analysis showed only the methanolic extract demonstrated antimicrobial activity with 11-mm inhibition diameter.