Artemisia argyi extract subfraction exerts an antifungal effect against dermatophytes by disrupting mitochondrial morphology and function

Artemisia argyi has a long history as raw materials for traditional medicine and functional diet in Asia. Since ancient times, A. argyi is commonly applied by folk to bathe and soak feet to disinfect and relieve itching. However, scientific evidence supporting its antifungal effect of A. argyi water extract (AAWE) against dermatophytes has not been revealed, especially on Trichophyton rubrum, Trichophyton mentagrophytes and Microsporum gypseum. This work aimed to clarify the scientificity of the folk usage of A. argyi by evaluating the antifungal effect and molecular mechanism of active subfraction from AAWE against dermatophytes. The results indicated that AAWE showed excellent antifungal effects against the three dermatophytes species, and its subfraction AAWE6 (separated by D101 macroporous resin) was the most effective subfraction. Exactly, the minimum inhibitory concentrations (MICs) of AAWE6 against T. rubrum, M. gypseum and T. mentagrophytes were 312.5, 312.5 and 625 μg·mL⁻¹, respectively. Moreover, the TEM results and enzyme activities related to cell wall integrity and cell membrane function showed that AAWE6 could break through the external protective barrier of T. rubrum (“cutting small holes in the wall”) and destroy the structure of internal mitochondria (“granary”). Furthermore, transcriptome data, RT-qPCR and biochemical assays confirmed that mitochondrial function was also severely disrupted, thus showing the inhibition of the TCA cycle and energy metabolism. Additionally, chemical characterization and molecular docking revealed the functional material basis of AAWE6 was flavonoids mainly composed of eupatilin (131.16 ± 4.52 mg·g⁻¹) and jaceosidin (4.17 ± 0.18 mg·g⁻¹). In conclusion, the subfraction AAWE6 from A. argyi exerts antifungal effects against dermatophytes by disrupting mitochondrial morphology and function. This research verified the traditional usage of A. argyi and will provide the scientific support for its anti-dermatophytic scientific utilization (Chinese patent: ZL202111161301.9).