Influence of US EPA 1622 method successive steps on the viability of Cryptosporidium oocysts
Influence of US EPA 1622 method successive steps on the viability of Cryptosporidium oocysts
复制标题
DOI：
10.2166/wst.2000.0132
复制
发表时间：
2000-01-01
影响因子：
2.7
通讯作者：
Dei-Cas, E
中科院分区：
文献类型：
--
作者：
Guyot, K;Gireaudot-Liepmann, MF;Dei-Cas, E
活的小隐孢子虫卵囊按照 US EPA 1622 方法进行处理，以确定需要连续过滤、洗脱和离心的程序会改变其完整性和活力（通过体外排泄确定）。还使用自来水样品中接种的卵囊来评估回收效率以及整个过程对卵囊活力的影响。发现通过 Envirochek Gelman 滤筒过滤不会损坏卵囊。与其他含有 80 和/或 SDS 的磷酸盐缓冲液（如 Gelman 缓冲液）相比，在洗脱步骤中使用 Laureth-12 缓冲液可导致更大的自发卵囊排出。然而，这一缺点与该缓冲液洗脱筒式过滤器捕获的卵囊的最佳效率以及其高回收效率之间存在广泛的平衡。因此，在预计卵囊浓度较低的水样中，使用 Laureth-12 缓冲液进行洗脱更为有利，通过它可以影响活力。离心速度（1,000-5,000 g）不会改变卵囊。
Viable Cryptosporidium parvum oocysts were processed by the US EPA 1622 method to determine ii the procedure that requires successive filtration, elution and centrifugation alters their integrity and viability (determined by in vitro excystation). Oocyst seeded in tap water samples were also used to evaluate recovery efficiencies and impact of the whole procedure on oocyst viability. Filtration through Envirochek Gelman cartridge was found not to damage oocysts. The use of Laureth-12 buffer during the elution step was shown to lead to greater spontaneous oocysts excystation than other phosphate buffers containing between 80 and/or SDS (like the Gelman buffer). However, this drawback was widely balanced against the best efficiency of this buffer to elute oocysts captured by the cartridge filter and therefore against its high recovery efficiency. Thus, in water samples in which the oocyst concentration is expected to be low, it is more advantageous to employ the Laureth-12 buffer for the elution through it can influence viability. Centrifugation speeds (1,000-5,000 g) did not alter oocysts.