The fungal population and distribution of aflatoxin-producing fungi in 30 samples of imported almond powder products purchased from retail markets were examined in this study. Total counts of fungi ranged from under 1.0 x 10 colony-forming units (CFU)/g to 8.5 x 10(3) CFU/g as determined with the dilution plating technique. The predominant fungi in the mould-contaminated almond samples were Asp...

In the present study the mould incidence, ergosterol and aflatoxin B1 (AFB1) contaminations were evaluated in different food based seed samples viz., chickpea, cowpea, green gram, groundnut, Indian bean, maize, sorghum, soya bean and sunflower collected from different agro-climatic regions of Karnataka (India). The agar plate and standard blotter methods were employed for determination of the f...

AIMS To establish a relationship between lipase gene expression and aflatoxin production by cloning the lipA gene and studying its expression pattern in several aflatoxigenic and nontoxigenic isolates of Aspergillus flavus and A. parasiticus. METHODS AND RESULTS We have cloned a gene, lipA, that encodes a lipase involved in the breakdown of lipids from aflatoxin-producing A. flavus, A. parasi...

Biological control of aflatoxin contamination by Aspergillus flavus is achieved through competitive exclusion of aflatoxin producers by atoxigenic strains. Factors dictating the extent to which competitive displacement occurs during host infection are unknown. The role of initial host contact in competition between pairs of A. flavus isolates coinfecting maize kernels was examined. Isolate succ...

The objective of this study was to evaluate biotic interaction between some mould species and active producer of aflatoxin B1 Aspergillus flavus NRRL 3251, co-cultured in yeast-extract sucrose (YES) broth. Twenty-five mould strains of Alternaria spp., Cladosporium spp., Mucor spp., A. flavus and A. niger, used as biocompetitive agents, were isolated from outdoor and indoor airborne fungi, scrap...

Aflatoxin contamination caused by the opportunistic pathogen A. flavus is a major concern in maize production prior to harvest and through storage. Previous studies have highlighted the constitutive production of proteins involved in maize kernel resistance against A. flavus' infection. However, little is known about induced resistance nor about defense gene expression and regulation in kernels...

Twelve species from six fungal genera were found to be associated with corn (Zea mays L.) grain samples collected from three main regions of Saudi Arabia. The average frequencies of the most common genera were Aspergillus (11.4%), Fusarium (9.5%), Penicillium (5.1%), and Alternaria (5.8%). Fifteen isolates of Aspergillus flavus were screened by HPLC for their ability to produce aflatoxins (AF)....

Histone acetyltransferases (HATs) help regulate fungal development and the production of secondary metabolites. In this study, we determined that the HAT AflGcnE influenced morphogenesis and aflatoxin biosynthesis in Aspergillus flavus. We observed that AflGcnE localized to the nucleus and cytoplasm during the conidial production and germination stages, while it was located mainly in the nucleu...

DNA methylation is essential for epigenetic regulation of gene transcription and development in many animals, plants and fungi. We investigated whether DNA methylation plays a role in the development and secondary metabolism of Aspergillus flavus, identified the DmtA methyltransferase from A. flavus, and produced a dmtA knock-out mutant by replacing the dmtA coding sequence with the pyrG select...

Aspergillus flavus is one of the most important producers of carcinogenic aflatoxins in crops, and the effect of water activity (a(w)) on growth and aflatoxin production of A. flavus has been previously studied. Here we found the strains under 0.93 a(w) exhibited decreased conidiation and aflatoxin biosynthesis compared to that under 0.99 a(w). When RNA-Seq was used to delineate gene expression...