Mycotoxin-contaminated food is an important public health issue. The aims of this study were to monitor mycotoxin contamination in Korean ginger and to investigate storage conditions to reduce mycotoxins. A total of 44 ginger samples (27 gingers and 17 ginger powders) were analyzed for contamination with aflatoxin B 1 , B 2 , G 1 , G 2 , ochratoxin A, deoxynivalenol (DON), nivalenol (NIV), and zearalenone (ZEA). Mycotoxin levels were quantified by ultra-performance liquid chromatography after immunoaffinity column clean-up. At least one mycotoxin was present in 37.03% of the ginger samples (10/27) and 41.17% of the ginger powder samples (7/17). NIV was the most frequently detected mycotoxin in the ginger samples (37.03%, 24.74-263.40 μg/kg), while DON (35.29%, 17.62-401.58 μg/kg), NIV (29.41%, 73.24-439.65 μg/kg), and ZEA (23.53%, 5.80-97.84 μg/kg) were frequently detected in the ginger powder samples. Aflatoxins and ochratoxin A were not detected in most of the ginger samples. In addition, two or more mycotoxins were found in ginger (25.93%) and ginger powder samples (29.41%). In the storage experiment, DON and NIV levels in ginger were significantly lower under 13℃ and 96% relative humidity than under the other conditions. This is the first report of DON and NIV in Korean ginger samples and the co-occurrence of Fusarium toxins.

In this study, we investigated the occurrence of mycotoxigenic fungi and mycotoxins in stored peanuts. Two types of peanuts, with and without shell, were stored for 12 and 6 months, respectively and the kernels from each type of peanut were collected and analyzed bimonthly. The stored peanuts were mainly contaminated with Aspergillus, Penicillium, and Fusarium species along with at least 26 other genera. Fungal frequency increased exponentially to reach 79.1±20.3% at 12 months of storage for peanuts with shell, whereas it increased sharply to 100% at 2 months for peanuts without shell. A. pseudoglaucus, A. chevalieri, and P. citrinum were prevalent in peanuts with shell, whereas A. flavus, P. crustosum, and P. polonicum were the most dominant species in peanuts without shell. Mycotoxin analysis revealed that ochratoxin A was detected in only one sample without shell (37.31 μg/kg), while aflatoxins were not detected. Fungal isolates known for mycotoxin production were confirmed to be producing various levels of mycotoxins in potato dextrose agar medium. Among the tested isolates (n=129), 59 (45.7%) produced aflatoxins (0.82-1,213.60 μg/kg), ochratoxin A (39.35-237.20 μg/kg), patulin (1.21-803.76 mg/kg), or fumonisins (0.27-13.70 mg/kg). To our knowledge, this is the first report on mycotoxin production by A. westerdijkiae, A. niger, A. welwitschiae, A. tubingensis, and P. expansum isolates from Korean peanuts. Overall, these results demonstrate the potential risk of not only aflatoxin and ochratoxin A but also patulin and fumonisin contamination in stored peanuts.