The growth and biofilm formation of Enterococcus faecalis in ethanol extract of Citrus aurantiifolia Indonesian species

Abstract

Context: Enterococcus faecalis is reported as a biofilm bacterium involved in the pathogenesis of tooth root canal infection. The ability to grow and form biofilms is the reason these bacteria are difficult to be eliminated. Aims: To analyze the antibacterial effect of Citrus aurantiifolia against the growth and biofilm formation of E. faecalis. Methods: This study used E. faecalis ATCC 29212 and ethanol extract of lime peel (Citrus aurantiifolia). The E. faecalis growth was assessed by spectrophotometry, and biofilm formation was examined with 1% violet crystals also visualized by microscope (magnification 400×). Results: Citrus aurantiifolia extract can inhibit the growth and biofilm formation of E. faecalis with varying quantities. Based on period incubations, a concentration of 6.25% had a better ability to suppress the growth of E. faecalis (<300 CFU/mL). The 75% concentration was the highest among other levels to inhibit the biofilms formation of E. faecalis that assumed the higher concentration of the extract, the most significant increase in inhibition of the biofilm formation of E. faecalis. Growth and biofilm formation of E. faecalis showed linearity in line with a concentration of 6.25% (p<0.05: 0.000) with a relatively stable relationship (r=0.506). Conclusions: Citrus aurantiifolia extract can inhibit the growth of E. faecalis that is in line with the inhibiton of the biofilm formation.