Effect of Lactiplantibacillus Plantarum THK-J112 Against Candida Overgrowth in Acne Complications

Secondary fungal infections resulting from disruptions caused by acne vulgaris treatments underscore the critical need for therapies that minimize dysbiosis while effectively targeting acne-associated pathogens. This study investigates Lactiplantibacillus plantarum THK-J112 cell-free supernatant (CFS) as a microbiome-stabilizing intervention against Candida overgrowth, utilizing a combination of genomic analysis and functional validation. In vitro evaluations demonstrated broad-spectrum antifungal activity, with inhibition zones of more than 10 mm against C. tropicalis KCTC 17762 and a minimum fungicidal concentration of 2.5 mg/mL. Scanning electron microscopy revealed profound Candida cell wall disruption, while cytotoxicity assays confirmed CFS safety for HaCaT keratinocytes and Caco-2 intestinal cells. The supernatant significantly reduced Candida adhesion to epithelial cells by up to 80.25%, outperforming Amphotericin B's anti-adhesive effects. Anti-inflammatory activity was evidenced by a 30.58% reduction in TNF-α and a 78.25% decrease in VEGF expression, suggesting protection against Candida-induced acne inflammation and hyperkeratinization. Mechanistic studies identified hydrogen peroxide (90.43 µM per 1 g/mL CFS) as the primary antimicrobial component. By integrating genomic evidence of biosynthetic potential with demonstrated multimodal activity-encompassing fungicidal, anti-adhesive, and anti-inflammatory effects-THK-J112 CFS emerges as a comprehensive therapeutic candidate. Genome sequencing revealed THK-J112's safety profile (absence of virulence factors) and identified a plantaricin J bacteriocin gene cluster while confirming vancomycin resistance. These findings address the dual challenge of treating acne-associated Candida complications while maintaining microbiome integrity, offering a promising alternative to conventional antifungals for patients experiencing treatment-induced dysbiosis. The study provides foundational evidence for probiotic-derived interventions in dermatological conditions complicated by fungal overgrowth.