In vitro studies with human liver indicate that the major catalyst involved in the bioactivation of the hepato-carcinogen aflatoxin B1 (AFB1) to its genotoxic 2,3-epoxide derivative is cytochrome P-450NF (P-450NF), a previously characterized protein that also catalyzes the oxidation of nifedipine and other dihydropyridines, quinidine, macrolide antibiotics, various steroids, and other compounds...

Produced by several species of Aspergillus, Aflatoxin B₁ (AFB₁) is a carcinogenic mycotoxin contaminating many crops worldwide. The utilization of fungicides is currently one of the most common methods; nevertheless, their use is not environmentally or economically sound. Thus, the use of natural compounds able to block aflatoxinogenesis could represent an alternative strategy to limit food and...

The effects of several naturally occurring and synthetic flavonoids on the metabolism of benzo(a)pyrene and aflatoxin B1 were evaluated. Addition of apigenin, chrysin, fisetin, flavonone, galangin, hesperitin, kaempferol, morin, myricetin, haringenin, or quercetin to human liver microsomes inhibited the hydroxylation of benzo(a)pyrene. In contrast to these results, the addition of flavone, nobi...

Treatment with Aflatoxin 8 1 (AFB1) resulted in inhibition of photosynthetic oxygen evolution in Chi orella fosca Shih.et Krauss. Treatments also induced a marked reduction of both chlorophyll and carotenoid contents. Inhibition of photosynthesis was manifested by loss of the variable component of Chlorophyll a (Chi a) fluorescence induction kinetics. Results are discussed in terms of the obser...

One of the major mechanisms of chemical protection against carcinogenesis, mutagenesis, and other forms of toxicity mediated by electrophiles is the induction of enzymes involved in their metabolism, particularly phase 2 enzymes such as glutathione S-transferases (GSTs), uridine diphosphate-glucuronosyltransferases, and NAD(P)H:quinone reductase. Furthermore, induction of phase 2 enzymes appear...

The chemical properties of β-glucans leading to their inhibition on aflatoxin (AF) production by Aspergillus flavus remain unclear. In this study, structurally modified lentinan derivatives were prepared by carboxymethylation, sulfation, and phosphorylation to explore their inhibition activity to AF synthesis. The results demonstrated that inhibitory activity of lentinan decreased at higher or ...

Gabliks, J. (Massachusetts Institute of Technology, Cambridge), W. Schaeffer, L. Friedman, and G. Wogan. Effect of aflatoxin B(1) on cell cultures. J. Bacteriol. 90:720-723. 1965.-Aflatoxin B(1), a metabolite of the mold Aspergillus flavus, is toxic to cell cultures. The toxic effect is evidenced by an inhibition of growth followed by progressive granulation, rounding, and finally sloughing of ...

Food and feedstuff contamination with aflatoxins (AFTs) is a serious health problem for humans and animals, especially in developing countries. The present study evaluated antifungal activities of two lactic acid bacteria (LAB) against growth and aflatoxin production of toxigenic Aspergillus parasiticus. The mycelial growth inhibition rate of A. parasiticus PTCC 5286 was investigated in the pre...

Cinnamaldehyde (CA) is marginally soluble in water, making it challenging to evenly disperse it in foods, and resulting in lowered anti-A. flavus efficacy. In the present study, nano-dispersed CA (nano-CA) was prepared to increase its aqueous solubility. Free and nano-dispersed CA were compared in terms of their inhibitory activity against fungal growth and aflatoxin production of A. flavus bot...

An inhibitor of aflatoxin biosynthesis localized in the seed coats of developing cotton was partially purified and characterized. Aqueous extracts from 25-day postanthesis seed coat tissue inhibited aflatoxin (B(inf1)) production in liquid cultures of Aspergillus flavus AF13. Inhibition was concentration dependent, with a 50% effective dose of 173 (mu)g of crude extract per ml of medium. The in...