Determination of the Mycotoxin Activity of Filamentous Fungi Isolated from the Intestinal Region of Adult Honey Bees by the PCR and UHPLC-Orbitrap-HRMS Methods

Honey bees are threatened by many fungal, parasitic and bacterial diseases. This study was aimed at identifying filamentous fungi colonizing the intestinal region of dead adult honey bees and determining resultant mycotoxin activity and its potential adverse implications for bee and human health by the PCR and UHPLC-Orbitrap-HRMS methods. For this purpose, dead bees were collected from the ground in front of 95 hives displaying mass mortality in the Hatay, Igdar and Bing & delta;l provinces, and 22 filamentous and 6 yeast-like fungi were isolated and identified from the intestinal region of these bees. Of the filamentous fungal isolates, 8 were identified as Aspergillus spp., 3 as Fusarium spp., 2 as Alternaria spp. 5 as Penicillium spp., 4 as Mucor spp., and 2 as Rhizopus spp.. The PCR analysis of the filamentous fungi using primers targeting the aflatoxin and ochratoxin A genes revealed the presence of aflatoxin in only 1 out of the 22 samples. Aflatoxin and ochratoxin were not detected in any of the other samples. The UHPLC-Orbitrap-HRMS method revealed the presence of aflatoxin B1 in 17, both B1 and B2 in 6, B1, B2 and G1 in 5, and aflatoxin G2 in 1 of the filamentous fungal samples. The results obtained in the present study suggest that filamentous fungi may produce mycotoxins in the intestinal region of honey bees, and thereby, honey bees may distribute mycotoxins into the environment and cause indirect adverse effects on human and animal health.