Bee Product-Based Antimicrobial Film-Forming Gels Targeting Staphylococcus aureus, Staphylococcus epidermidis, and Cutibacterium acnes for Anti-Acne Applications

Abstract

This study aimed to develop an optimized film-forming gel for topical anti-acne applications by evaluating the antibacterial efficacy of propolis, honey, and royal jelly, individually and in combination with low-dose salicylic acid. The antibacterial activities were assessed against Staphylococcus aureus, Staphylococcus epidermidis, and Cutibacterium acnes using the inhibition zone assay. Film-forming gels were developed by evaluating the effects of type and concentration of polymers and plasticizers. Each formulation was evaluated for visual appearance, pH, viscosity, and drying time, along with the appearance of the corresponding film. The findings noted that propolis (1% w/w) exhibited the strongest antibacterial activity among individual bee products, producing an inhibition zone of 20.0 ± 1.0 mm against S. aureus. The combination of bee products with low-dose salicylic acid (0.1% w/w) markedly enhanced antibacterial efficacy, particularly against C. acnes (inhibition zone 40.8 ± 0.8 mm). Incorporation of this combination into the optimized film-forming gel, containing polyvinyl alcohol, Carbomer® 940, polyethylene glycol 400, glycerin, and water, produced a formulation with balanced pH, suitable viscosity, 31 min drying time, and complete inhibition of S. aureus and S. epidermidis. Therefore, bee product-based film-forming gels, combined with low-dose salicylic acid, exhibited favorable physicochemical properties and showed promise as complementary anti-acne therapies.