Submitted to: ARS Food Safety and Inspection Service Research Workshop
Publication Type: Abstract Only
Publication Acceptance Date: 10/26/1997
Publication Date: N/A
Technical Abstract: Supercritical fluids are finding increased usage to replace organic solvents in extraction of mycotoxins from various matrices. We utilized supercritical fluid carbon dioxide (SC CO2) with an appropriate cosolvent to remove aflatoxin B1 from yellow/white corn and aflatoxin M1 from bovine liver. Supercritical fluid extraction (SFE) was performed with an Isco SFX extractor or on a larger scale extractor. Neat, sieved corn fractions from 3-50 gram batches were extracted, but liver was extracted by mixing liver puree with a sample dispersant, Hydromatrix. Pressure and temperatures up to 15,000 psi and 150 deg C were utilized to optimize recovery via SFE. Neither neat SC CO2 nor high pressure were sufficient to achieve high recoveries of B1 from yellow dent corn. Optimal extraction of B1 was accomplished at 5000 psi and 80 deg C using a 2:1 acetonitrile:methanol cosolvent at 15 volume %. Levels of aflatoxin B1 in yellow corn depended on sample size and age, whether SFE or solvent extraction were used. Extrapolation of extraction conditions to white corn did not result in equivalent recoveries of B1 at equal levels of contamination and sample size. Supercritical fluid or organic solvent extraction of M1 from liver was complicated by high levels of coextractives. Careful adjustment of SFE conditions, particularly amount of fluid/cosolvent utilized, resulted in M1 recoveries equivalent to those achieved with organic solvent. Both extracts required cleanup prior to liquid chromatographic analysis.