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A Microbiological Assay for Penicillic Acid 1
1Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska 68583.
Abstract:
Six bactertial cultures were studied in a search for an organism sensitive to penicillic acid suitable for use in a quantitative bioassay of this mycotoxin. A vegetative culture and a commercially prepared spore suspension of Bacillus subtilis were both sensitive to as little as 1 μg of penicillic acid and exhibited a linear relationship between 1 and 100 μg. The bioassay method was comparable in accuracy to thin layer chromatographic assay. The procedure was used to verify the biological activity of sample extracts, as well as to quantitate penicillic acid concentration in samples of liquid media and corn. The bioassay is sensitive, rapid (15-17 h), simple and inexpensive.
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