South Australian Water Corporation, Australian Water Quality Centre, 250 Victoria Square, Adelaide, SA 5000, Australia; School of Earth & Environmental Sciences, University of Adelaide, SA 5005, Australia.
South Australian Water Corporation, Australian Water Quality Centre, 250 Victoria Square, Adelaide, SA 5000, Australia.
Water Res. 2012 Nov 1;46(17):5735-5746. doi: 10.1016/j.watres.2012.08.003. Epub 2012 Aug 15.
The fate of five cyanobacterial metabolites was assessed in water sourced from Lake Burragorang (Warragamba Dam) in New South Wales, Australia. All of the studied metabolites were shown to be biodegradable in this water source. For some metabolites, biodegradation was influenced by factors, including temperature, location (within the water body) and seasonal variations. The biodegradation of the metabolites was shown to follow pseudo-first-order kinetics with rate constants ranging from 8.0 × 10(-4) to 1.3 × 10(-2) h(-1). Half-lives of the metabolites were also estimated and ranged from 2.2 to 36.1 d. The order of ease of biodegradability in this water source followed the trend: microcystin-LR ≥ cylindrospermopsin > saxitoxins > geosmin ≥ 2-methylisoborneol. The lack of detection of the mlrA gene during microcystin biodegradation suggests that these toxins may be degraded via a different pathway. While no metabolite-degrading organisms were isolated in this study, the inoculation of previously isolated geosmin- and microcystin-degrading bacteria into Lake Burragorang water resulted in efficient biodegradation of the respective metabolites. For example, microcystin-degrading isolate TT25 was able to degrade three microcystin variants to concentrations below analytical detection within 24 h, suggesting that inoculation of such bacteria has the potential to enhance biodegradation in Lake Burragorang.
对源自澳大利亚新南威尔士州沃勒甘巴湖（沃拉伦坝）的水中的五种蓝藻代谢物的命运进行了评估。在该水源中，所有研究的代谢物均表现出可生物降解性。对于某些代谢物，生物降解受到包括温度、位置（水体内部）和季节性变化在内的因素的影响。代谢物的生物降解遵循伪一级动力学，速率常数范围为 8.0×10(-4) 至 1.3×10(-2) h(-1)。还估计了代谢物的半衰期，范围为 2.2 至 36.1 d。在该水源中，生物降解容易程度的顺序为：微囊藻毒素-LR ≥ 节旋藻毒素 > 石房蛤毒素 > 土臭素 ≥ 2-甲基异莰醇。在微囊藻毒素生物降解过程中未检测到 mlrA 基因表明这些毒素可能通过不同途径降解。尽管在这项研究中未分离到代谢物降解生物，但将先前分离到的土臭素和微囊藻毒素降解细菌接种到沃勒甘巴湖中，导致相应代谢物的有效生物降解。例如，微囊藻降解分离株 TT25 能够在 24 小时内将三种微囊藻毒素变体降解至低于分析检测浓度，这表明接种此类细菌有可能增强沃勒甘巴湖中微囊藻毒素的生物降解。
