The worldwide predominance of microbial infections and oxidative stress-related disorders has caused a significant challenge to public health. These conditions are often intensified by factors like pollution, ultraviolet radiation, and microbial contamination [1]. Besides, growth in multi-drug resistant (MDR) bacteria has worsened the situation through complicated management of microbial infections increasing the health burden and morbidity [2]. In humans, commensal species like Staphylococcus epidermidis has an important role in maintaining microbial balance and host immunity. Antimicrobial defense mechanisms in hosts are enhanced through the production of lipopeptides by Staphylococcus epidermidis[3]. However, the shift of commensal organisms into opportunistic pathogens as a result of a dysbiosis state can contribute to systemic infections [4]. Staphylococcus aureus, a pathogen and occasional harmless colonizer in healthy individuals, has been frequently linked to invasive infections at various body sites [5]. Likewise, opportunistic pathogens like Pseudomonas aeruginosa have been linked to severe infections, particularly in immunocompromised individuals [6]. Therapies based on antimicrobial and antioxidant strategies often rely on synthetic compounds, which have adverse effects contributing to drug resistance over time [7]. This necessitates the development of safer and more effective bioactive compounds with dual functionality, such as antioxidant and antimicrobial activities. Beta-cryptoxanthin (β-CRX), a natural xanthophyll carotenoid, is recognized for its strong antioxidant capacity and provitamin A activity. Beta-cryptoxanthin antioxidant activity and modulation of immune responses have fascinated interest for therapeutic applications [1]. However, its combined use with other bioactive compounds remains largely unexplored.

Moreover, microbial-derived biosurfactant has gained impressive attention as safe and eco-friendly alternatives to synthetic antimicrobials. These amphiphilic molecules possess surface-active properties exhibiting antimicrobial, anti-adhesive, and antibiofilm activities [8]. Demonstration of disruption of bacterial membranes, inhibition of biofilm formation, and enhancement of co-administered antimicrobial agents' effectiveness has been reported [9]. A previous study showed the production of beta-cryptoxanthin and a novel biosurfactant by Kocuria marina DAGII. This study investigates the combined efficacy of β-CRX and a novel biosurfactant derived from Kocuria marina DAGII in mitigating free radicals and inhibiting a few opportunistic skin pathogenic bacteria like Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. The study aims to evaluate their antioxidant capacity, antibacterial activity, and underlying mechanisms like membrane permeability and biofilm disruption. This dual-functional approach could offer a promising, low-toxicity alternative to conventional therapeutics in addressing both oxidative damage and microbial infections.