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Release of Hypoglycin A from Hypoglycin B and Decrease of Hypoglycin A and Methylene Cyclopropyl Glycine
Anna Maria Engel1, Ahmed H El-Khatib1, Martin Bachmann1
1German Federal Institute for Risk Assessment, 10589 Berlin, Germany.
Toxins
|February 25, 2025
Summary
Ruminant microbes transform toxic hypoglycin A (HGA), hypoglycin B (HGB), and methylene cyclopropyl glycine (MCPrG) from sycamore maple seeds. These toxins are degraded, but HGB converts to HGA, impacting microbial activity and gas production.
Area of Science:
- Rumen microbiology
- Toxicology
- Animal nutrition
Background:
- Sycamore maple seeds contain toxic compounds hypoglycin A (HGA), hypoglycin B (HGB), and methylene cyclopropyl glycine (MCPrG).
- These toxins can affect ruminant health and microbial fermentation in the rumen.
- Understanding the transformation and effects of these toxins is crucial for animal health management.
Purpose of the Study:
- To investigate the transformation of HGA, HGB, and MCPrG in ovine ruminal fluid batch cultures.
- To assess the impact of these toxins on ruminal microorganisms through microbial metabolites.
- To compare the effects of pure toxins versus toxins present in sycamore maple seeds.
Main Methods:
- Ovine ruminal fluid batch cultures were incubated with a cellulose-starch substrate, pure toxins (PCM), or sycamore maple seeds (SMS).
- The ANKOM RF Gas Production System was used to monitor microbial activity over 48 hours.
- Liquid chromatography-tandem mass spectrometry (LC/MS-MS) analyzed toxin concentrations, while gas production, short-chain fatty acids, and NH3 concentration measured microbial activity.
Main Results:
- In pure toxin (PCM) incubations, HGA and MCPrG concentrations decreased rapidly, becoming undetectable within 24 hours.
- Sycamore maple seeds (SMS) showed an initial increase in HGA, concurrent with a decrease in HGB, suggesting HGB conversion to HGA.
- Microbial activity, indicated by gas production and metabolite concentrations, was higher with SMS compared to CSM and PCM, as seeds served as an additional substrate.
Conclusions:
- Ruminal microorganisms can transform and degrade HGA, HGB, and MCPrG.
- A significant conversion of HGB to HGA occurs, along with progressive transformation of HGA and MCPrG.
- Sycamore maple seeds can be utilized as a substrate by ruminal microbes, despite containing toxic compounds, leading to increased fermentation activity.
Keywords:
atypical myopathyphytotoxinsrumen fermentationsecondary plant metabolitessycamore maple treeMore Related Videos
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