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A Microbiological Assay for Penicillic Acid 1.
1Department of Food Science and Technology, University of Nebraska-Lincoln, Lincoln, Nebraska 68583.
Journal of Food Protection
|February 24, 2019
Summary
A new bioassay using Bacillus subtilis can accurately quantify penicillic acid, a mycotoxin. This sensitive, rapid, and inexpensive method is suitable for various sample types.
Area of Science:
- Microbiology
- Mycotoxicology
- Analytical Chemistry
Background:
- Penicillic acid is a mycotoxin requiring accurate quantification.
- Existing assay methods may have limitations in sensitivity, speed, or cost.
Purpose of the Study:
- To develop and validate a quantitative bioassay for penicillic acid.
- To identify a microbial organism sensitive to penicillic acid for bioassay development.
Main Methods:
- Screening of six bacterial cultures for sensitivity to penicillic acid.
- Utilizing Bacillus subtilis (vegetative and spore forms) for the bioassay.
- Comparing bioassay accuracy with thin-layer chromatographic assay.
Main Results:
- Bacillus subtilis demonstrated sensitivity to penicillic acid as low as 1 μg.
- A linear response was observed between 1 and 100 μg of penicillic acid.
- The bioassay showed comparable accuracy to thin-layer chromatography.
- The method was successfully applied to liquid media and corn samples.
Conclusions:
- A sensitive, rapid (15-17 hours), simple, and inexpensive bioassay for penicillic acid was developed using Bacillus subtilis.
- This bioassay is effective for verifying biological activity and quantifying penicillic acid in various samples.
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