Antiseptics and the Ocular Surface: In Vitro Antimicrobial Activity and Effects on Conjunctival and Corneal Epithelial Cells of a New Liposomal Ocular Spray Containing Biosecur® Citrus Extract

Abstract

Introduction:The study aimed to evaluate the in vitro antimicrobial activity of a new liposomal ocular spray containing the antiseptic Biosecur Ò citrus extract (Oftasecur, OFF-HEALTH, Florence, Italy) and its in vitro effects on cultured human corneal and conjunctival cells. Methods: Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of Oftasecur against Candida albicans and Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains, were determined. Human corneal and conjunctival epithelial cells in vitro were incubated for 10 and 30 min with Oftasecur or its components. The cytotoxicity was assessed through the release of cytoplasmic enzyme lactate dehydrogenase (LDH) into the medium; the 3-(4,5dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate the cell viability. Results: Oftasecur was active at dilutions ranging from 1:2 to 1:16 and it displayed bactericidal and fungicidal effect against all assayed microorganisms. Most of the reduction of Staphylococcus epidermidis vitality (65%) occurred within the first minute of exposure. The cytotoxicity of Oftasecur was similar to its vehicle, and the cell viability was significantly reduced only by Oftasecur in its undiluted form. Conversely, Biosecur induced a significant cytotoxicity in all the experiments. Conclusion: Oftasecur showed a rapid and wide-spectrum antibacterial activity, with an optimal in vitro tolerability profile.

Broad-Spectrum Antimicrobial Activity of Oftasecur and Visuprime Ophthalmic Solutions

“…In contrast, 10.1 µL of Oftasecur was required to impair bacterial growth. Consistent with our results, a preliminary study conducted by Mencucci and colleagues reported the antimicrobial effect of Oftasecur against S. aureus , S. epidermidis , S. pyogenes , E. coli , P. aeruginosa, and C. albicans , recording a bactericidal effect and fungicide against the microorganisms analyzed [ 33 ]. Otherwise, no studies to date have investigated the antimicrobial effect of Visuprime.…”

“…Both ophthalmic solutions were commercially available to soothe and protect the surface of the eye. In the ophthalmology field, antiseptics are becoming a relevant therapeutic approach due to their broad-spectrum activity for nonselective mechanisms of action [ 33 , 34 ]. Little evidence reports the antimicrobial potential of Visuprime and Oftasecur.…”

Prophylaxis of Ocular Infection in the Setting of Intraocular Surgery: Implications for Clinical Practice and Risk Management

“…Biosecur is a non-toxic organic alcohol-free compound containing citrus bioflavonoids suspended in glycerin. Mencucci et al tested in vitro a liposomal commercial formulation, Oftasecur Ocular Spray (OFFHEALTH S.p.a., Florence, Italy) containing 0.2% biosecur, reporting bactericidal and fungicidal effects versus all common microorganisms at dilutions varying from 1:2 to 1:16 [73]. Moreover, Vagge et al tested the compound in vivo in a prospective study on patients undergoing IVIs, reporting a significant decrease in conjunctival bacterial load after a 4-day prophylactic treatment [74] (Fig.…”

Anti-staphylococcal activity of a polyphenol-rich citrus extract: synergy with β-lactams and low proficiency to induce resistance

“…These studies focused on its use as surface cleaner or supported its application as food treatment in the food industry. The citrus extract is also included as active ingredient in a liposomal formulation commercialized as medical device for the ocular antisepsis ( Vagge et al, 2021 ; Mencucci et al, 2022 ; Mazzantini et al, 2024 ). Nevertheless, evidence on the potential application of B in the clinical practice to treat staphylococcal infections is still lacking.…”

“…Time-kill assay was carried out using S. aureus ATCC 6538 and S. epidermidis CI-1 as model organisms, as previously described ( Mencucci et al, 2022 ). Briefly, microbes were suspended in 0.01 M Sodium Phosphate Buffer (NaPB, pH 7.2) to a density of 0.5 McF and about 10 6 CFU inoculated in NaPB containing the extract at the MIC value (0.0031% for S. aureus ATCC 6538 and 0.0063% for S. epidermidis CI-1).…”