Water Research Centre, Ecology and Environmental Sciences, School of Biological Sciences, University of Adelaide, South Australia, 5005, Australia.
Australian Water Quality Centre, South Australia Water Corporation, Adelaide, South Australia, 5000, Australia.
Water Res. 2017 Nov 1;124:454-464. doi: 10.1016/j.watres.2017.07.073. Epub 2017 Aug 2.
Cyanobacteria represent a health hazard worldwide due to their production of a range of highly potent toxins in diverse aquatic environments. While planktonic species have been the subject of many investigations in terms of risk assessment, little is known about benthic forms and their impact on water quality or human and animal health. This study aimed to purify isolates from environmental benthic biofilms sampled from three different drinking water reservoirs and to assess their toxin production by using the following methods: Enzyme-Linked Immunosorbent Assay (ELISA), High-Performance Liquid Chromatography (HPLC), Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) and quantitative PCR (qPCR). Microscopic observation of the isolates allowed the identification of various filamentous cyanobacterial genera: Anabaena (benthic form), Calothrix and Nostoc from the Nostocales and Geitlerinema, Leptolyngbya, Limnothrix, Lyngbya, Oxynema, Phormidium and Pseudanabaena representing non-heterocystous filamentous cyanobacteria. The Phormidium ambiguum strain AWQC-PHO021 was found to produce 739 ng/mg of dry weight (d/w) of cylindrospermopsin and 107 ng/mg (d/w) of deoxy-cylindrospermopsin. The Nostoc linckia strain AWQC-NOS001 produced 400 ng/mg (d/w) of a microcystin analogue. This is the first report of hepatotoxin production by benthic cyanobacteria in temperate Australian drinking water reservoirs. These findings indicate that water quality monitoring programs need to consider benthic cyanobacteria as a potential source of toxins.
蓝藻在世界范围内构成健康危害，因为它们在各种水生环境中产生一系列强效毒素。尽管浮游物种已成为风险评估的许多调查主题，但对底栖形式及其对水质或人类和动物健康的影响知之甚少。本研究旨在从三个不同的饮用水水库中采集的环境底栖生物膜中分离出纯化物，并通过以下方法评估其毒素产生：酶联免疫吸附测定（ELISA）、高效液相色谱法（HPLC）、液相色谱-串联质谱法（LC-MS/MS）和定量聚合酶链反应（qPCR）。对分离物的显微镜观察允许鉴定出各种丝状蓝藻属：鱼腥藻（底栖形式）、念珠藻和念珠藻目，以及胶质鞘藻属、鞘丝藻属、鱼腥藻属、念珠藻属、单歧藻属、裂须藻属、鞘藻属、鱼腥藻属、Oxynema、Phormidium 和 Pseudanabaena，代表非异形胞丝状蓝藻。发现 Phormidium ambiguum 菌株 AWQC-PHO021 产生 739 ng/mg 干重（d/w）的圆柱鱼腥藻素和 107 ng/mg（d/w）的脱氧圆柱鱼腥藻素。 Nostoc linckia 菌株 AWQC-NOS001 产生 400 ng/mg（d/w）的微囊藻毒素类似物。这是在澳大利亚温带饮用水水库中发现底栖蓝藻产生肝毒素的首次报道。这些发现表明，水质监测计划需要将底栖蓝藻视为毒素的潜在来源。
