Determination of in vitro antimicrobial and antibiofilm activity of Hypericum crenulatum against some food pathogens and its phenolic content

The study investigates the antimicrobial effects of the Hypericum crenulatum ethanolic (HCE) extract against 14 different food pathogens and their biofilm-forming abilities in response to HCE treatment. The phenolic acid composition of the HCE extract was also determined using an HPLC-DAD detector. The antimicrobial activity of HCE extract was assessed using the disc diffusion and microdilution methods. According to the findings, the methicillin-resistant Staphylococcus aureus ATCC 43300, Listeria monocytogenes RSKK 472, and Listeria innocua ATCC 33090 strains exhibited the lowest minimum inhibitory concentration (MIC) values at a concentration of 2 μg mL−1. Based on the disc diffusion test results, the largest zone of inhibition of HCE extract against foodborne pathogens was seen against Bacillus cereus, and the diameter of the inhibition zone increased with the concentration of HCE extract (P < 0.05). In terms of phenolic acid composition of HCE extract, the phenolic acids with the highest and lowest amounts were caffeic acid (59.92 mg g−1) and p-coumaric acid (13.61 μg g−1), respectively. Our study determined that the HCE extract demonstrated antimicrobial, bactericidal, and antibiofilm activities against some foodborne pathogens. These effects reveal its potential for improving food safety by inhibiting the growth of these pathogens.