Urinary excretion of 8,9-dihydro-8-(7'-guanyl)-9-hydroxyaflatoxin (AFB-Gua) was studied in areas of different liver cancer incidence in Kenya. Of 983 urine samples analysed for AFB-Gua by high-performance liquid chromatography, 12.6% gave positive results. The chemical identity of AFB-Gua was verified by synchronous scanning fluorescence spectrophotometry. A moderate degree of correlation betwe...

Two activities involved in terminal pathway conversion of sterigmatocystin to aflatoxin B1 were isolated from an aflatoxin-nonproducing mutant of Aspergillus parasiticus (avn-1), and the time course of appearance of the activities in culture was determined. Subcellular fractionation of fungal mycelia resolved the two activities into a postmicrosomal activity which catalyzed conversion of sterig...

The inhibitory effect of four basic aflatoxins on interferon induction by influenza virus in LLC-MK2 cell monolayers follows a structure-activity series with decreasing potency in the order aflatoxin B1 greater than G1 greater than B2 approximately G2. Of the four aflatoxins, B1 was the most deleterious to both cell growth and the viability of cells in confluent cultures. The fact that higher l...

Wild-type Aspergillus parasiticus produces, in addition to the colorless aflatoxins, a number of pigmented secondary metabolites. Examination of these pigments demonstrated that a major component was an anthraquinone, averufanin. Radiolabeling studies with [14C]averufanin showed that 23% of the label was incorporated into aflatoxin B1 by the wild type and that 31% of the label was incorporated ...

2,3-Dihydro-2,3-dihydroxyaflatoxin B1 (dihydrodiol) was formed as a major metabolite in the incubation of aflatoxin B1 with rat and hamster liver microsomes. The yield of the dihydrodiol was maximal at pH 6.5, was reduced nicotinmide adenine dinucleotide phosphate- and cytochrome P-450-dependent, and was increased 2- to 4-fold by pretreatment of the animals with phenobarbital; pretreatment with...

BACKGROUND Aflatoxin contamination of foods is a worldwide problem. Chronic aflatoxin exposure is associated with kidney damage. Curcumin is a herbal agent, used in medicine with a wide range of beneficial therapeutic effects. OBJECTIVE to evaluate the effect of curcumin against experimentally induced aflatoxicosis on the renal cortex of adult male albino rats. MATERIALS AND METHODS Forty a...

In order to study the contamination of Aspergillus flavus and aflatoxin production in pistachio cultivars in the Semnan province, eight cultivars of pistachio were collected from major pistachio growing areas. Using the serial dilution method, ground pistachio kernels were inoculated on plates containing AFPA medium and incubated at 28° C. This experiment was performed using three replications ...

BACKGROUND Aflatoxins are toxic fungal metabolites enable to contaminate a wide range of natural substrates. This contamination can be host-specific for different plant species. In this study, the ability of a toxigenic Aspergillus parasiticus to produce various aflatoxins on major Iranian cereals was evaluated with special focus on plant susceptibility to toxin production at cultivar level. ...

The metabolism of aflatoxin B2 by postmitochondrial supernatant fractions of duck, rat, mouse, and human livers was studied in an in vitro system. Duck liver had a much higher level of activity than had tissues from other species. Postmitochondrial supernatant equivalent to 0.2 g whole liver metabolized 40 to 80% of the initial substrate in 30 min, compared to less than 6% for the other species...

1. Male weanling rats were given for extended periods diets containing gum arabic or wheat offal or various offal fractions. The fractions included two lipid fractions, a water-soluble extract and a modified-acid-detergent (MAD)-fibre extract. The diets contained either low concentrations of aflatoxin B1 (induced rats) or were free from this source of aflatoxin (non-induced rats). The distribut...