Monitoring Mycotoxin Contamination in Mississippi
Overall Objective: Using the Agilent 6460 Series Triple Quadrupole LC/MS System, we plan to expand our total aflatoxin monitoring to include individual AFB1, AFB2, AFG1, AFG2 detection, as well as fumonisins, ochratoxins, deoxynivalenol, and zearalenone. Understanding the production of the individual aflatoxins and the presence of the other mycotoxins when coupled to geo-referenced weather and soil conditions, as well as agronomical practices, will allow scientists to better understand the complex host-pathogen interaction, and perhaps develop a conceptual model to predict the occurrence of emerging toxins.
Identification of Factors Involved in Degradation or Sequestering of Aflatoxin to Reduce the Economic Impact
Using an interdisciplinary approach and keeping with ideologies of the Multistate Research Project, S1033, "Control of Food-Borne Pathogens in Pre- and Post-Harvest Environments" we propose to evaluate the biological degradation of aflatoxin, by Aspergilli, as well as investigate the use of binders to sequester aflatoxin in fermented corn products. Our objective is two-fold: first, to investigate and define the proteome, as well as the associated genes of selected stains involved in the degradation or modification of aflatoxins and second, to adapt theses selected cultures to the industrial ethanol fermentation process and asses the utility of binders in order to lower mycotoxin concentrations in the byproduct, distiller’s grain, important for livestock feed.
Decreasing The Impact Of Aflatoxin On Corn And Distillers Grains
Objectives: In an effort to reduce mycotoxin contamination we will continue to use a proteomic approach to identify proteins involved in the aflatoxin degradation phenomenon. We will screen a variety of clay like materials to determine mycotoxin-binding efficacy. Using a volatile profile library for several species of Aspergilli we will use SPME-GC/MS coupled to Arc-GIS mapping to allow for rapid fungal detection in fields, as well as provide information on the complex host pathogen relationship.
Oxidative Remediation Of Aflatoxin-Contaminated Corn
Progress has been made towards minimizing the occurrence of aflatoxin in corn through improved farming practices and development of new corn lines; however, contamination remains a significant problem, especially in growing seasons coinciding with drought. Therefore, our team will target two priority areas: amelioration technology for aflatoxin contaminated grain and improved testing procedures. In terms of effective aflatoxin amelioration methods, two approaches will be evaluated. First, chemical oxidative treatments have been shown to degrade aflatoxins in corn and other crops very rapidly. Our research will focus on the efficacy of using ozone to treat harvested corn with the goal of eliminating the presence of aflatoxin while salvaging the inherent nutritive value of the grain.
A Maize (Zea mays) Line Resistant to Herbivory Constitutively Releases (E)-β-Caryophyllene
Maize is an important US agricultural crop is often destroyed by insect feeding. Maize generates a variety of responses to pest attack, from activation of wound-response pathways such as jasmonic acid (JA) biosynthesis to the release of volatile compounds. Mp708 is an inbred line resistant to feeding by fall armyworm (FAW). The underlying resistance mechanisms are not completely understood. Mp708 has been shown to constitutively express JA and other octadecanoid compounds prior to infestation. Tx601, a genotype susceptible to FAW, activates JA pathway only in response to feeding, suggesting Mp708 is “primed” for attack. Analysis of the volatiles released by the resistant and susceptible lines was conducted using SPME-GC/MS. We have demonstrated the presence of (E)-β-caryophyllene commonly associated with resistance, released constitutively in Mp708. FAW larvae show a preference for Tx601 over Mp708 whorl tissue. Identifying volatiles correlated with resistance could lead to the integration of these traits into commercial varieties.