Aflatoxin is a toxic, carcinogenic mycotoxin primarily produced by Aspergillus parasiticus and Aspergillus flavus. Previous studies have predicted the existence of more than 20 genes in the gene cluster involved in aflatoxin biosynthesis. Among these genes, aflK encodes versicolorin B synthase, which converts versiconal to versicolorin B. Past research has investigated aflK in A. parasiticus, b...

BACKGROUND The effect of probiotic bacteria (Lactobacillus acidophilus and L. casei) as safe organisms was examined on fungal growth and aflatoxin gene regulation in Aspergillus parasiticus. METHODS The fungus was cultured in presence of two different concentrations of L. acidophilus and L. casei in MRS broth medium. Mycelia dry weight is indicated as criteria to evaluate fungal growth. Besid...

Two morphologically different Aspergillus parasiticus strains, one producing aflatoxins, abundant conidia but few sclerotia (BN9) and the other producing O-methyl-sterimatocystin (OMST), copious sclerotia but a low number of conidia (RH), were used to assess the role of crzA which encodes a putative calcium-signaling pathway regulatory protein. Under standard culture conditions, BN9DeltacrzA mu...

Aflatoxin contamination of corn is an important problem internationally, particularly in tropical and subtropical conditions that favor infection and synthesis by Aspergillus. Environmental conditions (drought) and agronomic practices i.e. N fertilization have been reported as favorable to aflatoxin synthesis in the field. This study was undertaken to investigate whether the contamination of co...

AIMS To compare the biosynthetic gene cluster sequences of the main aflatoxin (AF)-producing Aspergillus species. METHODS AND RESULTS Sequencing was on fosmid clones selected by homology to Aspergillus parasiticus sequence. Alignments revealed that gene order is conserved among AF gene clusters of Aspergillus nomius, A. parasiticus, two sclerotial morphotypes of Aspergillus flavus, and an unn...

Variations in moisture and substrate in preharvest corn kernels and cottonseed were linked with the ability of Aspergillus parasiticus to infect the seed and produce aflatoxin. Osmotic pressures and moisture content (MC) levels of developing starch-rich corn kernels and lipid-rich cottonseed were determined. For in vivo studies, corn kernels and cottonseed were inoculated with A. parasiticus co...

Aspergillus section flavi strains isolated from peanuts, wheat and soybean grown in Argentina were screened for aflatoxins (type B and G) and cyclopiazonic acid (CPA) production. Aspergillus flavus was the predominant species in all substrates, although there was almost the same proportion of A. flavus and Aspergillus parasiticus in peanuts. Aspergillus nomius was not found. Incidence of aflato...