摘要：Abstract:
Cyanobacteria, an important group of microorganisms present in many drinking water sources, may produce cyanotoxins and taste and odor (T&O) compounds, posing health risk and aesthetic issues to consumers. Therefore, quantification of cyanotoxins, T&O compounds and the producing cyanobacteria in drinking water reservoirs are needed for proper management of water supplies. Microscopy, gas chromatograph, and liquid chromatograph are currently used as standard practices to quantify the producing cyanobacteria, T&O compounds, and cyanotoxins, respectively.However, these establishedmethods require experienced biologists, sophisticatedinstrumentation, and/or long turn-around time. Bio-molecular methods, such as quantitativepolymerase chain reaction (qPCR), offer the capability of quantifying functional gene concentrations of targeted cyanobacterial metabolites in short time, which may provide additional information and time for the management of water supplies.
The aim of this study is to develop and apply an on-site mobile monitoring system to quantify the concentrations of functional genes responsible for the production of four commonly observed noxious cyanobacterial metabolites, including two toxins, microcystin (MCY) and cylindrospermopsin (CYN), and two taste and odor (T&O) compounds, 2-methylisoborneol (2-MIB) and trans-1,10-dimethyl-trans-9-decalol (geosmin) in Taiwan’s reservoirs. Primer and probe sets were first designed and tested with pure cyanobacteria strains, including producers and non-producers of the targeted metabolites. Then, the method was integrated with a mobile laboratory and applied in quantifying the toxin- and odorant-producing species in 38 drinking water reservoirs in Taiwan and her off-shore islands. The qPCRresults obtained in the reservoir samples well correlated with the cyanotoxins and T&O compound concentrations measured for the corresponding samples. The results suggest that the qPCR based approach may offer a quick and specific detection method for the monitoring of cyanotoxin and T&O compound producing cyanobacteria in water sources, allowing more time for reservoir and water utility managers to action when faced with cyanobacterial bloom episodes.
