Nerol-induced apoptosis associated with the generation of ROS and Ca2+ overload in saprotrophic fungus Aspergillus flavus
The contamination of food with Aspergillus flavus and subsequent aflatoxins is one of the most serious safety problems in the world. In this study of nerol (NEL)’s antifungal mechanism of action, we observed morphological and physiological changes in Aspergillus flavus. We found that NEL resulted in elevated levels of reactive oxygen species (ROS) and calcium ions (Ca2+). On ROS assays, compared with the controls, the proportion of fluorescent cells treated with concentrations of 0.25, 0.5, 1, and 2 μL/mL NEL increased to 8.4 ± 1.07%, 10.2 ± 1.72%, 13.4 ± 0.50%, and 26.2 ± 4.21%, respectively. Increased mitochondrial dysfunction and oxidative stress induced by the interactions between Ca2+ and ROS subsequently activate the release of cytochrome c and caspase activity. Characteristic changes of apoptosis were also observed via various detection methods, including phosphatidylserine externalization, nuclear condensation, and DNA fragmentation. Meanwhile, we found that the expression of CaMKs increased significantly in NEL-treated cells. In conclusion, our findings indicate that NEL has great potential as an eco-friendly antifungal agent for food preservation.
KeywordsNEL A. flavus Antifungal Calcium Reactive oxygen species Apoptosis
This study was funded by National Natural Science Foundation of China (31671944, 31570028), Six Talent Peaks Project of Jiangsu Province (SWYY-026), Qing Lan Project of Jiangsu Province, Natural Science Foundation by Xuzhou City (KC17053), the Industry-University-Academy Prospective Joint Research Project of Jiangsu Province (BY2016028-01), Jiangsu Science and Technology Agency Project (BK20141148), and the PAPD of Jiangsu Higher Education Institutions.
Compliance with ethical standards
Conflict of interest
All authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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