Aspergillus flavus (A. flavus) and Aspergillus fumigatus (A. fumigatus) are the main fungi that cause stonebrood in honey bees. Additionally, these fungi cause the declines of honey bee population and the economic loss in the beekeeping industry. In this study, the efficacy of a disinfectant, composed to chlorine dioxide (10%, w/v) and quaternary ammonium compound (12.5%, w/v), was evaluated against A. flavus and A. fumigatus. A fungicidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to test fungi for 30 min at 4°C. The disinfectant and test fungi were diluted with low and high organic matter (OM) suspension according to treatment condition. On low OM condition, the fungicidal activity of the disinfectant against A. flavus and A. fumigatus was all 2.0 fold dilutions. On high OM condition, the fungicidal activity of the disinfectant against A. flavus and A. fumigatus was all 1.25 fold dilutions. The recommended dilution ratio of the disinfectant in low and high OM was 1.6 and 1.0 fold dilution, respectively. As the disinfectant possesses fungicidal efficacy against A. flavus and A. fumigatus, the disinfectant can be used to prevent the stonebrood in honey bees.

This experiment was conducted to investigate the effects of mixed culture with mycotoxigenic and non-mycotoxigenic fungi on mycotoxin production. For this work, Aspergillus flavus (aflatoxin producing strain), Aspergillus niger (non-mycotoxigenic strain) and Penicilhum griseofulvum (patulin producing strainvere cultured in 5 ml SLS medium for 15 days under single or mixed culture. Affatoxin was determined by direct competitive ELISA, whereas, patulin was measured by HPLC. The mycelial growth, pH and total acidity were also observed by general methods. The mycelial growth was slightly decreased in the mixed culture, meanwhile total acidity was increased and pH was shown lower than that in single culture. Aspergillus flavus produced 145 ㎍/ml of aflatoxin for 12 days single culture, but in mixed culture, aflatoxin was decreased to 93%, and was shown as 10.16 ㎍/ml level. Patulin production in mixed culture was also decreased to 69.3% and was shown only 23.72 ㎍/ml level as compared with in single culture.