Food supplements with known antimicrobial activity such as cinnamon extracts are being consumed more widely as a part of daily diet with pandemic. Cinnamon extracts can be found also in the composition of many functional foods and dietary supplements. This study was carried out to investigate the in vitro antimicrobial activities of the extracts of cinnamon on some probiotic (Lacticaseibacillus rhamnosus, Lactiplantibacillus plantarum, Lactobacillus acidophilus, Lactobacillus gasserii, Lacticaseibacillus casei) bacteria. According to the findings, it was determined that cinnamon ethanol, methanol and chloroform extracts inhibited the growth of the investigated probiotic lactobacilli. Diameter of inhibition zones for ethanol, methanol, and chloroform extracts were measured at values ranging from 14.93-30.68, 13.19-30.17, and 10.03-25.55 mm, respectively. MIC values were found to be 0.26-10.41 mg/mL, 0.35-12.43 mg/mL, and 0.65-15.99 mg/mL in the same order. The obtained data will help in the preparation of the formulations of probiotic and symbiotic nutraceutical products and other functional foods and in determining the dosages of use.

Keywords: Cinnamon extracts, probiotics, antibacterial effect, minimum inhibition concentrations.