Fungal Genomics & Biology
Open Access

Abstract

Effect of Gamma Radiation on Growth and Mycotoxin Production of Alternaria alternata

Braghini R, Rocha LO, Pozzi CR, Frizzarin A, Reis TA and Corrêa B

The ubiquitous genus Alternaria contains many species that are able to invade cereals, oleaginous plants and other crops. Alternaria alternata is considered one of the most important species and can produce several mycotoxins under favorable conditions of temperature and humidity, including the economically important toxins: alternariol (AOH) and alternariol monomethyl ether (AME). The aim of this study was to evaluate the radio-sensitivity of Alternaria alternata spores through different gamma radiation doses. A. alternata growth and the production of AOH and AME were then analyzed. After fungal irradiation with 2 kGy, 5 kGy and 7 kGy, the spores were suspended with sterile distilled water followed by inoculation on wheat grains. The count of the colony-forming units per gram (CFU/g) was performed using Dichloran Rose Bengal Chloramphenicol (DRBC) and Dichloran Chloramphenicol Agar Malt Extract (DCMA); AOH and AME were analyzed using Liquid Chromatography coupled with Mass Spectrometer (LC-MS). Results showed that fungal growth and toxin production increased with the increase of radiation dosage. The implications of these findings in relation to the resistance of A. alternata spores to gamma irradiation are discussed.