The Candida albicans Inhibitory Activity of the Extract from Papaya (Carica papaya L.) Seed Relates to Mitochondria Dysfunction

The inhibitory activity of the papaya seed extract (PSE) on Candida albicans (C. albicans) was determined by turbidimetry method. The inhibitory mechanisms were also evaluated from the prospective of reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP) decrease, and the activities of four complex enzymes in mitochondria respiratory chain. Results obtained from this study indicated that the PSE exhibited an effective inhibitory activity on C. albicans and induced significant accumulation of ROS and collapse of MMP. The Complex I and Complex III exhibited continues significant decrease in mitochondrial enzyme activity assays, but the Complex II and Complex IV activities were not positively correlated. Furthermore, the GC-MS analysis demonstrated that the PSE represents a rich and high-purity source of benzyl isothiocyanate (BITC), which indicated the BITC may be responsible for the mitochondrial dysfunction.