Antibacterial activity of strawberry fruit extract against Streptococcus sanguinis (ATCC 10556)

Abstract

Introduction: Streptococcus sanguinis is a facultative anaerobic Gram-positive bacteria known as a pioneer that plays a role in creating the biofilm in the oral cavity. Strawberry fruit (Fragaria x ananassa) is an edible fruit widely used for the study as their active compound synergy to improve health. This study aims to analyse the antibacterial activity of strawberry fruit against S. sanguinis (ATCC 10556). Methods: An explorative study was conducted with high concentration methanol extract from strawberry fruit. Antibacterial activity was tested on the methanol extract; afterwards, the extract was fractionated and divided into three fractions: water, ethyl acetate, and hexane. Zone of inhibition was used to assess the most effective fraction among those three, then continued by testing for Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). Results: Inhibitory zone of the ethyl acetate fraction from strawberry fruit 1%, 2%, 3% ,4% and 5% sequentially were 7.3 mm,10.2 mm, 12.3 mm, 16.3 mm and 16.1 mm. Ethyl acetate fraction of 4% was the most effective to create the zone of inhibition with a size of 16.3 mm compared to the others. The Minimum Inhibitory Concentration (MIC) value was 0.25%. It was obtained by diluting a 4% ethyl acetate fraction on a microplate. The Minimum Bactericidal Concentration (MBC) was 2%. Conclusion: Ethyl acetate fraction was an effective fraction from strawberry fruit and had antibacterial activity against S. sanguinis with the inhibitory zone in the concentration of 4%, MIC of 0.25%, and MBC of 2%.