Kontaminacija toksigenim vrstama gljiva i njihovim mikotoksinima uzoraka kukuruza iz različitih regiona u Srbiji

This study was carried out in order to investigate the natural occurrence of toxigenic fungi and levels of zearalenone (ZEA), deoxynivalenol (DON) and aflatoxin B1 (AFB1) in the maize stored immediately after harvesting in 2016 and used for animal feed in Serbia. A total of 22 maize samples were collected from four different districts across the country: City of Belgrade (nine samples), Šumadija (eight samples), Podunavlje (four samples) and Kolubara (one sample). Toxigenic fungi were identified according to the morphological characteristics whereas the mycotoxins contamination were detected using biochemistry enzyme-linked immuno-sorbent (ELISA) assay. The tested samples were mostly infected with Aspergillus, Fusarium and Penicillium spp., except that one sample originated from Kolubara was not contaminated with Aspergillus species. Fusarium graminearum was the most common species in the maize sample from Kolubara district (60%), F. verticillioides in the maize samples from Podunavlje (43.75%) and City of Belgrade (22.4%) districts, and Penicillium spp. in the maize samples from Šumadija district (26.38%). In the analysed maize samples the presence of Aspergillus species was low (0-1.78%). Mycotoxicological analysis revealed the presence of zearalenone (ZEA), deoxynivalenol (DON) and aflatoxin B1 (AFB1) in all the investigated samples, except that DON and AFB1 were not recorded in the samples from Podunavlje and Kolubara districts, respectively. The investigated samples were highly contaminated with ZEA, with incidence of 100% for the samples from Šumadija, Podunavlje and Kolubara districts and 88.89% for the samples from City of Belgrade district. In addition, the samples contamination with DON was 100% and 22.2% for the samples from Šumadija, Kolubara and City of Belgrade, districts, respectively. The highest number of AFB1 positive samples was found in Šumadija district (87.5%), while in the City of Belgrade and Podunavlje districts, 55.56% and 50% AFB1 positive samples were established, respectively. Generally, remarkable infection of all the tested samples with toxigenic fungal species from Aspergillus, Fusarium and Penicillium genera were recorded. In addition, high contamination with mycotoxins ZEA, DON and AFB1 were also recorded; nevertheless, only in one sample the level of DON exceeded the allowed legal limit (1750 μg kg-1 ) according to Regulation for unprocessed maize. Therefore, permanent mycological and mycotoxicological analyses of maize grain are necessary for risk assessment of fungal and mycotoxin contamination throughout the food chain.Ispitivanja u ovom radu izvedena su s ciljem da se odredi prirodna pojava potencijalno toksigenih gljiva iz rodova Aspergillus, Fusarium i Penicillium i sadržaj mikotoksina zearalenona (ZEA), deoksinivalenola (DON) i aflatoksina B1 (AFB1) u kukuruzu uskladištenom neposredno posle berbe u 2016. godini i korišćenom za ishranu životinja. Ukupno 22 uzoraka zrna kukuruza sakupljeni su iz četiri regiona u Srbiji: Beogradski (devet uzoraka), Šumadijski (osam uzoraka), Podunavski (četiri uzorka) i Kolubarski (jedan uzorak). Toksigene vrste gljiva su identifikovane na osnovu morfoloških osobina, a sadržaj mikotoksina određen je pomoću biohemijske, imunoadsorpcione enzimske metode (ELISA). Ispitivani uzorci kukuruza većinom su bili inficirani sa Aspergillus, Fusarium i Penicillium spp., izuzev što u uzorku iz Kolubarskog regiona nisu bile identifikovane Aspergillus vrste. Fusarium graminearum bila je najučestalija vrsta u uzorku kukuruza iz Kolubarskog regiona (60%), F. verticillioides u uzorcima iz Podunavskog (43,75%) i Beogradskog regiona (22,4%) i Penicillium spp. u uzorcima iz Šumadijskog regiona (26,38%). U ispitivanim uzorcima kukuruza zastupljenost Aspergillus vrsta bila je niska (0-1,78%). Mikotoksikološkim analizama ustanovljeno je prisustvo zearalenona (ZEA), deoksinivalenola (DON) i aflatoksina B1 (AFB1) u svim ispitivanim uzorcima kukuruza, izuzev što DON nije detektovan u uzorcima iz Podunavskog a AFB1 u uzorku iz Kolubarskog regiona. Ispitivani uzorci su visoko kontaminirani sa ZEA, 100% uzoraka iz Šumadijskog, Podunavskog i Kolubarskog regiona i 88,89% uzoraka iz Beogradskog regiona. Isto tako, sa DON bilo je kontaminirano 100% uzoraka iz Šumadijskog i Kolubarskog regiona i 22,2% iz Beogradskog regiona. Najveći broj AFB1 pozitivnih uzoraka ustanovljen je u Šumadijskom regionu (87,5%), dok je u Beogradskom i Podunavskom regionu ustanovljeno 55,56% i 50% AFB1 pozitivnih uzoraka, respektivno. Uopšteno razmatrajući, u ovim analizama ustanovljena je visoka zastupljenost toksigenih vrsta u svim ispitivanim uzorcima kukuruza. Isto tako, ustanovljena je visoka kontaminiranost uzoraka sa mikotoksinima ZEA, DON i AFB1, iako je samo u jednom uzorku sadržaj DON premašio dozvoljeni limit (1750 μg kg-1 ) prema zakonskoj regulativi za neprerađeni kukuruz. Zbog toga, stalne mikološke i mikotoksikološke analize zrna kukuruza neophodne su radi ocene rizika od gljivične i mikotoksin kontaminacije u lancu ishrane