Saxitoxin: A Comprehensive Review of Its History, Structure, Toxicology, Biosynthesis, Detection, and Preventive Implications
Abstract
1. Introduction
2. Historical Traceability and Structural Analysis
2.1. First Detection and Process
2.2. Molecular Structure Characteristics
3. Molecular Biosynthesis
3.1. Biosynthetic Gene Clusters and Synthetic Pathways
3.2. Environmental Regulation of Toxin Synthesis
3.3. Latest Research Developments
4. Bioenrichment of STX: Pathways, Influencing Factors, and Ecological Impacts
5. Toxicity Mechanisms of STX
5.1. Blocking Mechanism of STX on NaVs
5.2. Association of β Subunits in the Action of STX
5.3. Affinity Difference in Different Subtypes of NaVs to STX
5.4. Potential Toxicity Targets of STX
5.5. Synergistic Effect of STX with TTX
6. Self-Resistance Mechanisms to STX Enlighten Treatment Development
6.1. Target Protein Resistance Mutations
6.2. Toxin Sequestration
6.3. Biotransformation and Metabolism
7. Detection
8. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Stage | Technical Method | LOD * | Application Scenarios | Key Features | Ref |
---|---|---|---|---|---|
On-site rapid screening | Daphnia acute toxicity bioassay | 0.3–10.7 ng Eq.STX/L | Aquatic product preliminary screening | Low cost and simple operation | [158] |
MIST Alert™ rapid test | 40 μg Eq.STX/100 g | Aquatic product preliminary screening | Equipment-free and adapted for on-site rapid turnaround | [168] | |
Laboratory confirmation and quantification | ELISA | 0.015 ng/mL | Positive sample screening and preliminary quantification | High stability and applicable for rapid triage of large-scale samples | [196] |
HPLC (post-column oxidation method) | 0.1 μg/kg | Routine sample quantification | High specificity | [181] | |
LC-MS/MS | 0.1 μg/kg | Complex matrices and multitoxin simultaneous analysis | High specificity and capable of structural confirmation | [178] | |
Research-grade analysis and mechanism verification | Neuro-2a cell-based assay | 2 ng/L | Toxicological mechanisms and low-dose effect studies | Direct correlation between STX ion channel blockade toxicity and biological effect simulation | [197] |
Receptor-binding assay | 2 ug Eq.STX/L | Toxin–receptor interaction mechanism | Real-time reflection of binding kinetics and high sensitivity | [198] |
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Deng, H.; Shang, X.; Zhu, H.; Huang, N.; Wang, L.; Sun, M. Saxitoxin: A Comprehensive Review of Its History, Structure, Toxicology, Biosynthesis, Detection, and Preventive Implications. Mar. Drugs 2025, 23, 277. https://doi.org/10.3390/md23070277
Deng H, Shang X, Zhu H, Huang N, Wang L, Sun M. Saxitoxin: A Comprehensive Review of Its History, Structure, Toxicology, Biosynthesis, Detection, and Preventive Implications. Marine Drugs. 2025; 23(7):277. https://doi.org/10.3390/md23070277
Chicago/Turabian StyleDeng, Huiyun, Xinrui Shang, Hu Zhu, Ning Huang, Lianghua Wang, and Mingjuan Sun. 2025. "Saxitoxin: A Comprehensive Review of Its History, Structure, Toxicology, Biosynthesis, Detection, and Preventive Implications" Marine Drugs 23, no. 7: 277. https://doi.org/10.3390/md23070277
APA StyleDeng, H., Shang, X., Zhu, H., Huang, N., Wang, L., & Sun, M. (2025). Saxitoxin: A Comprehensive Review of Its History, Structure, Toxicology, Biosynthesis, Detection, and Preventive Implications. Marine Drugs, 23(7), 277. https://doi.org/10.3390/md23070277