بررسی برخی پارامترهای موثر بر قارچ Aspergillus section Flavi و تولید آفلاتوکسین در طول دوره انبارداری پسته در استان سمنان

Aflatoxins are carcinogenic secondary metabolites that are mainly produced by the fungi Aspergillus flavus and A. parasiticus on various agricultural crops and their products. Today, food contamination with mycotoxins is one of the most important health problems. The World Health Organization in different countries have set specific rules and regulations for the production, consumption and import of food according to the serious risks of mycotoxins. Storage condition is one of the effective factors in promoting fungal growth and mycotoxin production. In this research, effective parameters on contamination develpment, fungal growth and aflatoxin production during storage was estimated in some stores of Damghan's town. So, in 21 stores in Damghan's town, 21 pistachio nut samples were taken and relative parameters of stores consist of sampling date, temperature, humidity, store conditions and …, were investigated. Then, samples transferred to laboratory for investigating contamination condition to Aspergillus section Flavi, by culturing on specific media AFPA with 3 repetitions. Therefore, 3 to 5 days after incubation, grown colonies on the plate surface were counted and isolated. On the basis of statistical analysis, there was a significant difference in samples contamination to Aspergillus section Flavi between various samples. The results showed that in Damghan's stores, there isn't significant difference between samples contamination to Aspergillus section Flavi and temperature, humidity requirements and storage pest infestation. In addition, the aflatoxigenic potential of Aspergillus section Flavi isolated colonies proved that toxigenic ability is various among isolates. More than 88% of isolates were able to produce one or several types of aflatoxins and less than 12% of the isolates produced no aflatoxin.