Antiaflatoxigenic effect of fullerene C ₆₀ nanoparticles at environmentally plausible concentrations

摘要

Increased interest in fullerene C_(60)and derivatives in recent years implies an intensification of their environmental spread. Yet, the potential risks for living organisms are largely unknown, including the interaction of C_(60)with fungal organisms. This may be especially relevant for mycotoxigenic fungi since C_(60)may both scavenge and produce reactive oxygen species (ROS), and oxidative stress induces mycotoxin production in fungi. Therefore, this study examined effects of environmentally plausible concentrations of C_(60)(0, 10, 50, and 100?ng/mL) on Aspergillus flavus growth and aflatoxin production in culture media. In addition, ROS-dependent oxidative stress biomarkers—thiobarbituric acid reactive substances (TBARS), reduced and oxidised glutathione ratio, superoxide dismutase isoenzymes, catalase, glutathione peroxidase, and glutathione reductase were determined in mycelia. Nanoparticles of fullerene C_(60)(nC_(60)) did not exhibit strong antifungal activity against A. flavus . At the same time, nC_(60)caused an antiaflatoxigenic effect at 10–100?ng/mL, and 50?ng/mL unexpectedly enhanced aflatoxin production. The TBARS content, reduced and oxidised glutathione ratio, and copper, zinc superoxide dismutase activity suggest that 10?ng/mL nC_(60)exerted antioxidative action and reduced aflatoxin B1 production within fungal cells. Detected prooxidative effects of 50?ng/mL fullerene exceeded cellular defenses and consequently enhanced aflatoxin B1 production. Finally, the results obtained with 100?ng/mL nC_(60)point to prooxidative effects, but the absence of increase in aflatoxin output may indicate additional, presumably cytotoxic effects of nC_(60). Thus, a range of rather low levels of nC_(60)in the environment has a potential to modify aflatoxin production in A. flavus . Due to possible implications, further studies should test these results in environmental conditions. Electronic supplementary material The online version of this article (10.1186/s13568-018-0544-0) contains supplementary material, which is available to authorized users.