Aflatoxins are carcinogenic metabolites produced by several strains of Aspergillus flavus group in food and feed. Cluster genes in aflatoxin biosynthesis pathway contain structural, regular and unassigned genes , nor-1 , ver-1 , and omt-1 are structural genes that coding for key enzymes and aflR is a regulatory gene that plays a key role in the production of aflatoxin and is affecting on the s...

Objective: Aflatoxin is known as one of the most important mycotoxins that threatens of human life. The toxin is produced by Aspergillus species which are common cause of contamination of agricultural products. For this reason, the use of organic compounds has always been considered in order to inhibit the growth of fungi and production of toxin. The aim of this study was to investigate the eff...

The health risks associated with ingesting food contaminated mycotoxins, particularly aflatoxin-contaminated staple foods like maize and other cereals, have been widely studied. However, there is little knowledge about the role of inhalation pathogenic fungi as bioaerosols in air from handling crops an occupational risk. This paper presents a study aimed at determining level airborne aflatoxin-...

AIMS A relative quantification system (RQ-PCR) was used to monitor the correlations between the activity of the nor-1 (=aflD) gene of Aspergillus flavus using real-time PCR in relation to phenotypic aflatoxin B(1) (AFB(1) ) production and populations of A. flavus in stored peanuts at three water activity levels (a(w) , 0·95, 0·90 and 0·85) for 6 weeks. METHODS AND RESULTS Real-time PCR was us...

background: the effect of curcumin as a natural safe compound with different biological activities was examined on fungal growth and aflatoxin production in aspergillus parasiticus nrrl 2999. methods: the fungus was cultured in presence of serial two-fold concentrations of curcumin (125-2000 µg/ml) in yeast extract sucrose broth for 3 days at 28°c. mycelia dry weight was determined as an index ...

The eukaryotic bZIP transcription factors are critical players in organismal response to environmental challenges. In fungi, the production of secondary metabolites (SMs) is hypothesized as one of the responses to environmental insults, e.g. attack by fungivorous insects, yet little data to support this hypothesis exists. Here we establish a mechanism of bZIP regulation of SMs through RsmA, a r...

Genes involved in intermediary and secondary metabolism in fungi are frequently physically linked or clustered. For example, in Aspergillus nidulans the entire pathway for the production of sterigmatocystin (ST), a highly toxic secondary metabolite and a precursor to the aflatoxins (AF), is located in a ∼54 kb, 23 gene cluster. We discovered that a complete ST gene cluster in Podospora anserina...

This study aims at evaluating the effects of Zataria multiflora (Z. multiflora) essential oil (EO) on growth, aflatoxin production and transcription of aflatoxin biosynthesis pathway genes. Total RNAs of Aspergillus parasiticus (A.parasiticus) ATCC56775 grown in yeast extract sucrose (YES) broth medium treated with Z. multiflora EO were subjected to reverse transcription- polymerase chain react...

Among the enzymatic steps in the aflatoxin biosynthetic pathway, the conversion of O-methylsterigmatocystin to aflatoxin has been proposed to be catalyzed by an oxidoreductase. Transformants of Aspergillus flavus 649WAF2 containing a 3.3-kb genomic DNA fragment and the aflatoxin biosynthesis regulatory gene aflR converted exogenously supplied O-methylsterigmatocystin to aflatoxin B1. A gene, or...

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. be...