Environmental DNA (eDNA) is a useful tool for biological monitoring of a target species by detecting DNA contained in environmental samples. However, the suppression of eDNA degradation after sample collection is a major issue when estimating the presence of a target species. Recently, benzalkonium chloride (BAC) was shown to dramatically suppress the degradation of eDNA in fish species from freshwater environments. However, the effect of this inexpensive reagent has not yet been tested in the other fish and shellfish species. We examined changes in eDNA concentrations for three target species (Corbicula japonica, Lateolabrax japonicus, and Anguilla japonica). eDNA was measured in samples containing added BAC. The effects of storage temperature (25°C, 4°C, and −30°C) and storage periods (periods up to 21 d) were also measured to determine how sample degradation was affected. We observed that BAC addition was effective in suppressing eDNA degradation, and its influence was similar among species but not storage temperatures. The concentrations of eDNA with BAC for all three species did not decrease with storage period, except for L. japonicus at 25°C and 4°C. Our results suggest that BAC affects eDNA degradation universally for a variety of species inhabiting both freshwater and brackish water.

中文翻译：

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使用苯扎氯铵抑制与不同储存温度和时间有关的水样中环境DNA降解

通过检测环境样品中包含的DNA，环境DNA（eDNA）是用于对目标物种进行生物学监测的有用工具。但是，在估计目标物种的存在时，抑制样品收集后eDNA降解是一个主要问题。最近，已证明苯扎氯铵（BAC）可以显着抑制淡水环境中鱼类的eDNA降解。但是，这种廉价试剂的效果尚未在其他鱼类和贝类物种中进行过测试。我们检查了三种靶标物种（日本bic，日本瓢虫和日本An）的eDNA浓度变化）。在含有添加的BAC的样品中测量eDNA。还测量了储存温度（25°C，4°C和-30°C）和储存时间（长达21 d）的影响，以确定样品降解的影响方式。我们观察到，添加BAC可有效抑制eDNA降解，并且其影响在物种间相似，但在储存温度下却不一样。除在25°C和4°C的刺参外，三种物种中BAC的eDNA浓度均未随保存期降低。我们的结果表明，BAC对居住在淡水和咸水中的多种物种普遍影响eDNA降解。