Abstract
Kaolinite stands out as a promising natural geomaterial for developing new therapeutic systems aimed at addressing global health challenges, such as multidrug-resistant infections. In this study, we report on the formulation and biological activity of a therapeutic mixture composed of white micronized kaolinite (KAO) and Ziziphora essential oil (ZEO), intended for topical application on infected wounds. GC–MS analysis revealed that the primary component of ZEO is pulegone, constituting 72.98% of the oil. ZEO demonstrated good bioactivity against bacterial and fungal strains (MIC 1.25–5 mg/mL). Additionally, ZEO at a concentration of 0.0156% (0.156 mg/mL) was found to significantly stimulate collagen synthesis. The antimicrobial activity of the tested KAO–ZEO mixture formulation (30% KAO/0.25% ZEO in an excipient base) showed the highest effectiveness against Candida spp. (MIC 0.08–25 mg/mL) and Gram-positive bacteria (MIC 0.16–25 mg/mL), with lower activity against Gram-negative bacteria (MIC 25–50 mg/mL). Moreover, the KAO–ZEO mixture was nontoxic (cell viability near 100%) to human skin fibroblasts according to the ISO 10993-5 standard and promoted collagen synthesis by skin cells. This is the first documented formulation combining KAO and ZEO, demonstrating significant antimicrobial properties along with the ability to stimulate collagen production in fibroblasts. These properties highlight KAO–ZEO as a promising novel treatment, which may synergize with current care standards and improve wound healing outcomes.