2010 Annual Report
1a.Objectives (from AD-416)
To collaborate in the development of a real-time electronic sensor to detect the growth of Aspergillus flavus on corn.
1b.Approach (from AD-416)
ARS will perform microbiological experiments to obtain data on the volatile gases produced by Aspergillus flavus growing on corn in vitro under laboratory conditions. Sensor Development Corporation will utilize this data to develop a chip-based electronic sensor that detects the major volatiles as determined by ARS.
Our stakeholder, Sensor Development Corporation (SDC), received funding for a new two-year phase II Small Business Innovation Research grant beginning in Winter of 2009-2010. This funding replaced an earlier grant which funded research during FY 2009-2010. The grant provided funding for Agricultural Research Service (ARS) (New Orleans, LA) use of a needed Tenax volatile trapping unit and an improved library of spectra of volatile compounds used for identification of detected secondary metabolic volatiles produced by Aspergillus flavus, a producer of aflatoxin, a potent carcinogen in crops. The grant also funded two university students to work part-time on this project.
During FY 2010, ARS (New Orleans, LA) continued to identify secondary metabolic products (not needed for growth) produced by aflatoxin-producing strains of Aspergillus flavus, as well as, Aspergillus flavus strains that do not produce this toxin, on sterile cracked corn. Also studied were volatiles produced by sterile cracked corn. Comparison of the results allowed the identification of volatiles unique for the toxigenic strains of Aspergillus flavus when growing on corn. The produced volatiles were also correlated with the presence of aflatoxin produced by the fungus.
SDC has used the data to develop a series of prototype instruments that use proprietary sensor chips and mathematical formulas to detect the volatiles specific for toxigenic Aspergillus flavus. This prototype unit is scheduled to undergo Beta testing in corn elevators during late FY 2010–2011. If successful, this unit will be the first commercially available real-time sensor for toxigenic Aspergillus flavus growth and aflatoxin production in stored corn. Research progress was monitored through teleconferencing, visits to cooperators' labs, and scientific discussions at professional society meetings.