Are spirolides converted in biological systems?--A study
Bernd Christian1, Anja Below, Nicole Drebler
1Institute for Nutrition, Friedrich-Schiller-University, Dornburger Strabe 25, D-07749 Jena, Germany. blchbe@uni-jena.de
Toxicon : Official Journal of the International Society on Toxinology
|February 12, 2008
Summary
Spirolides, marine toxins found in shellfish, can resist breakdown in digestive systems. This resistance, due to specific methyl groups, suggests potential human toxicity risks from consuming contaminated seafood.
Area of Science:
- Marine Biology
- Marine Natural Products Chemistry
- Food Safety
Background:
- Spirolides are potent marine toxins originating from scallops and phytoplankton.
- These macrocycles exhibit rapid toxicity, linked to their cyclic imine structure.
- Methyl groups on the spirolide ring may confer resistance to hydrolysis.
Purpose of the Study:
- To investigate the enzymatic hydrolysis of spirolides with vicinal methyl groups.
- To assess the stability of these spirolides in shellfish digestive enzyme extracts.
- To evaluate the potential human health risks associated with consuming contaminated shellfish.
Main Methods:
- Enzymatic assays using cell-free tissue extracts from Mytilus edulis, Pecten maximus, and Crassostrea gigas.
- Incubation of specific spirolide variants with shellfish enzymatic extracts.
- Analysis of spirolide stability and potential degradation products.
Main Results:
- Spirolides with an additional methyl group on the imine ring demonstrated resistance to enzymatic hydrolysis.
- These resistant spirolides, unlike spirolide A and B, were not effectively degraded by shellfish enzymes.
- The stability suggests a prolonged presence of these toxins in shellfish tissues.
Conclusions:
- Spirolides with specific methyl group configurations are resistant to enzymatic breakdown in digestive systems.
- This resistance increases the risk of spirolide accumulation in shellfish.
- Consumption of contaminated shellfish poses a potential human health hazard due to persistent spirolide toxicity.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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