Anode catalysts comprising MoS 2 and composite metal sulfides have been investigated for electrochemical oxidation of hydrogen sulfide in solid oxide fuel cells ͑SOFCs͒ at temperatures up to 850°C. All catalysts exhibited good electrical conductivity and catalytic activity at all temperatures. MoS 2 and composite catalysts were found to be more active than Pt, an established catalyst for high-temperature H 2 S-air fuel cells at 650-830°C. However, MoS 2 itself sublimes above 450°C. In contrast, composite catalysts ͑M-Mo-S͒ derived from a mixture of sulfides of Mo and other transition metals ͑Fe, Co, Ni͒ have been shown to be stable and effective for electrochemical conversion of H 2 S in SOFCs up to 850°C. Electrical contact is poor between platinum current collecting layers and metal sulfide anode catalysts. This problem has been overcome by mechanically mixing conductive Ag powder into the anode layer, instead of applying a thin layer of platinum to the anode.

The problem of food spoilage due to Aspergillus flavus (A. flavus) needs to be resolved. In this study, we found that the minimum inhibitory concentration of cinnamaldehyde (CA) that inhibited A. flavus was 0.065 mg/ml and that corn can be prevented from spoiling at a concentration of 0.13 mg/cm 3. In addition to inhibiting spore germination, mycelial growth, and biomass production, CA can also reduce ergosterol synthesis and can cause cytomembrane damage. Our intention was to elucidate the antifungal mechanism of CA. Flow cytometry, fluorescence microscopy, and western blot were used to reveal that different concentrations of CA can cause a series of apoptotic events in A. flavus, including elevated Ca 2+ and reactive oxygen species, decrease in mitochondrial membrane potential (ψ m), the release of cytochrome c, the activation of metacaspase, phosphatidylserine (PS) externalization, and DNA damage. Moreover, CA significantly increased the expression levels of apoptosis-related genes (Mst3, Stm1, AMID, Yca1, DAP3, and HtrA2). In summary, our results indicate that CA is a promising antifungal agent for use in food preservation.

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