Antimicrobial, Antifungal, Antioxidant Activity and Phytochemical Investigation of Phenolcarboxylic Acids by GC–MS of Raspberry (Rubus idaeus L.) Shoot Lipophilic Extract

Abstract Aim To determine the content of phenolcarboxylic acids using gas chromatography–mass spectrometer (GC–MS) in the obtained extract, conduct a study of the antimicrobial, antifungal, and antioxidant activities of Rubus idaeus shoot lipophilic extract. Material/methods The quantification of phenolcarboxylic was accomplished through GC–MS, antioxidant activity was assessed by potentiometric method, antimicrobial and antifungal activities were determined by well method. Results The 8 compounds were identified by the GC–MS method. The vanillic acid (2.59 ± 0.08 mg/100 g), benzoic acid (1.51±0.08 mg/100 g), and ferulic acid (0.79±0.04 mg/100 g) dominated in the obtained lipophilic R. idaeus shoot extract. Bacillus subtilis (17.00 ± 0.50 mm) was the most sensitive to lipophilic extract, whereas Proteus vulgaris was the most resistant to the lipophilic extract. Moreover, Candida albicans was medium sensitive to lipophilic extract (13.50 ± 0.50 mm). The antioxidant activity was 1.00 mmol-equiv./mdry res; according to Maslov's antioxidant level classification it has low level. Conclusions The lipophilic extract from R. idaeus shoots contains various phenolcarboxylic acids, including vanillic acid, benzoic acid, ferulic acid, p-hydroxybenzoic acid, syringic acid, gentisic acid, salicylic acid, and phenylacetic acid, with the highest concentrations observed for vanillic, benzoic, and ferulic acids. This study highlights the antimicrobial and antifungal properties of the R. idaeus shoot lipophilic extract. However, the obtained lipophilic extract showed a relatively low level of antioxidant activity. Consequently, the derivatives of phenolcarboxylic acids play a substantial role in the antimicrobial and antifungal effects, whereas their contribution to antioxidant activity appears to be limited.