Evaluation of fatty acid composition and antimicrobial activity of supercritical fluid extract of <i>Rubus ulmifolius</i> Schott fruits

In this study, we continue our research on <i>Rubus ulmifolius</i> 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 <i>R. ulmifolius</i>. 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 <i>Streptococcus mutans</i>. Kirby-Bauer analysis showed only the methanolic extract demonstrated antimicrobial activity with 11-mm inhibition diameter.