An aspect of mycotoxin biosynthesis that remains unclear is its relationship with the cellular management of reactive oxygen species (ROS). Here we conduct a comparative study of the total ROS production in the wild-type strain (SU-1) of the plant pathogen and aflatoxin producer, Aspergillus parasiticus, and its mutant strain, AFS10, in which the aflatoxin biosynthesis pathway is blocked by disruption of its pathway regulator, aflR. We show that SU-1 demonstrates a significantly faster decrease in total ROS than AFS10 between 24 h to 48 h, a time window within which aflatoxin synthesis is activated and reaches peak levels in SU-1. The impact of aflatoxin synthesis in alleviation of ROS correlated well with the transcriptional activation of five superoxide dismutases (SOD), a group of enzymes that protect cells from elevated levels of a class of ROS, the superoxide radicals (O2−). Finally, we show that aflatoxin supplementation to AFS10 growth medium results in a significant reduction of total ROS only in 24 h cultures, without resulting in significant changes in SOD gene expression. Our findings show that the activation of aflatoxin biosynthesis in A. parasiticus alleviates ROS generation, which in turn, can be both aflR dependent and aflatoxin dependent.

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Current production agriculture systems typically focus on yield outcomes at all costs. By shifting to best management practices based on regenerative farming principles, however, agricultural systems worldwide could maintain or even improve yields while sequestering atmospheric carbon (C) into soil organic matter (SOM). To demonstrate the effectiveness of regenerative principles at simultaneously benefiting agriculture and reducing greenhouse gasses, their C sequestration potential was examined through SOM data from 486 soil sampling locations from multiple farms throughout the coastal plains of South Carolina. These data were compared over varying multiple-year periods between 2013 and 2017 as their land management practices shifted from conventional methods to those based on the regenerative-based practice of cover cropping. The implementation of cover crops in crop rotations resulted in statistically significant mean SOM percentage increases of 0.11 (p ≤ 0.001), 0.11 (p ≤ 0.001), and 0.55 (p ≤ 0.001) for sampling sites converted into rotations utilizing cover crops for two, three, and four years, respectively. When averaged out per year for each sampling group, this results in an average of 622, 425, and 1584 lbs./acre/year of C fixed from the atmosphere and retained in the soil as organic matter. Increases were observed across all soil types sampled in the study with soil texture not significantly influencing a soils' ability to increase soil OM or sequester atmospheric C through cover crop implementation. The calculations based on the coastal plains' soils studied here demonstrate the promising potential of the application of regenerative farming principles to not only restore degraded biodiversity, recycle nutrients, improve farm profitability, and reduce chemical inputs, but also to sequester atmospheric C and simultaneously help reduce the effect of global climate change while creating healthy soils.