First report of anatoxin-a encoding gene in isolated cyanobacterial strains from Malaysia

@#Aims:This study focus on the presence of cyanobacterial toxin in Malaysia and anatoxin-a-encoding gene was detected in this study and the status of cyanobacterial toxins in Malaysia can now be clarified.Methodology and results:As part of status determination of cyanobacterial toxins in Malaysia, cyanobacterial strains have been isolated from different environments and identified using cyanobacterial16S rRNA gene sequence. PCR assay was carried out to detect the presence of cyanobacterial toxin-encoding genes in these isolated strains by amplifying genes encoded for microcystin, anatoxin-a, cylindrospermopsin and saxitoxin. Using molecular identification of 16S rRNA gene sequences, a total of forty-two cyanobacterial strains were identified, which belongs to eighteen different genera of Synechococcus, Cyanobium, Synechocystis, Chroococcidiopsis, Leptolyngbya, Nodosilinea, Limnothrix, Pseudanabaena, Cephalothrix, Aerosakkonema, Oscillatoria, Alkalinema, Pantanalinema, Planktolyngbya, Scytonema, Nostoc, Hapalosiphonand Symphyonemopsis. The toxicity of these strains was tested using PCR amplification of toxin-encoding genes using specific primers.Conclusion, significance and impact of study:Anatoxin-a (ATX) gene,which involved in the biosynthesis of anatoxin-Awas detected in two isolated strains namelyLimnothrixsp. B15 and Leptolyngbyasp. D1C10.This study focus on the the presence of cyanobacterial toxin in Malaysia can now be determined as potential threat because anatoxin-a-encoding gene was detected in this study and the status of cyanobacterial toxins in Malaysia can now be clarified.

The Human Health Effects and Risk Assessment of Cyanobacterial Toxins / 环境与健康杂志

Cyanobacterial toxins may pose a threat to human health through drinking water and recreational water exposure. The official guideline limits of cyanobacterial toxins have not been established. The human health effects, exposure routes, possible guideline limits and calculation method were introduced in the present paper. The knowledge will provide a base to undertake risk management for the toxins and will also contribute to establishing official guideline limits of cyanobacterial toxins in water and will be benefit for ensuring the safety of drinking water.