Antibacterial Activity of Fusidic Acid-Loaded Electrospun Polylactide Fiber Fleeces Against Periodontopathogenic Species

<b>Background/Objectives:</b> The effect of fusidic acid on oral bacteria, especially on Gram- negative periodontopathogenic species, has not yet been investigated. This in vitro study aimed to analyze the antibacterial effect of fusidic acid alone and as an active component in electrospun poly(L-lactide-co-D/L-lactide) fiber fleeces. <b>Methods:</b> Minimal inhibitory concentrations (MIC) of fusidic acid and metronidazole (control) were determined for various oral bacteria. Eluates were collected from electrospun poly(L-lactide-co-D/L-lactide) fiber fleeces loaded with 10 and 20 wt% fusidic acid over a period of 28 d. Antibacterial activity was analyzed by means of a microdilution assay. Cytotoxicity was observed toward human gingival fibroblasts (HGFs). <b>Results:</b> All tested Gram-positive and Gram-negative oral bacteria were susceptible to fusidic acid. The lowest MIC was observed for <i>Porphyromonas gingivalis</i> (MIC < 0.062 µg/mL). Compared to the antibacterial activity of metronidazole, that of <i>Porphyromonas gingivalis</i> was suppressed by significant lower fusidic acid concentrations (<i>p</i> < 0.01). The eluates obtained from electrospun poly(L-lactide-co-D/L-lactide) fiber fleeces inhibited the growth of <i>P. gingivalis</i>, <i>S. aureus</i>, <i>A. viscosus</i>, and <i>A. neslundii</i> over a course of 28 days. The largest inhibition zones were detected for <i>Porphyromonas gingivalis</i> in case of the 20 wt% concentrations. The eluates were not cytotoxic toward HGFs. <b>Conclusions:</b> It was shown that fusidic acid has significant antibacterial potential. The results of the present investigation suggest that fusidic acid alone or delivered by electrospun fiber fleeces might be attractive for controlling oral pathogenic bacteria.