标准摘要
[中文适用范围]： 本文件规定了一种用于水中肠球菌（包括粪肠球菌、屎肠球菌、耐久肠球菌、鸟肠球菌、鸡肠球菌和产气肠球菌）计数的方法。该方法基于目标微生物在液体培养基中的生长，并通过参考MPN表或使用合适的MPN信息程序，计算微生物的“最可能数”（MPN）。该方法适用于饮用水、浴用水（淡水或海水）以及其他类似类型的水，包括含有相当数量悬浮物质的水样，并可在存在高达1 × 10⁶ / 100 ml的异养菌的情况下，在（26 ± 2）小时内检测出每100 ml水样中1个菌落形成单位（CFU）的肠球菌。对于淡水和海水浴用水，建议将水样稀释1:10以提高肠球菌的计数准确性。本文件所述的检测方法基于肠球菌表达的酶ß-D-葡糖苷酶，可在24小时内给出确认结果，无需对阳性孔进行进一步检测。本文件不适用于瓶装水，因为该方法尚未针对瓶装水进行验证，因此不在本文件的适用范围内，除非实验室在使用前已对本方法进行了适当的性能验证。 [外文原描述]： This document specifies a method for the enumeration of intestinal enterococci in water, including Enterococcus faecalis , Enterococcus faecium , Enterococcus durans , Enterococcus avium , Enterococcus gallinarum , Enterococcus hirae , Enterococcus casselifavus . The method is based on the growth of target organisms in a liquid medium and calculation of the “most probable number” (MPN) of microorganisms by reference to MPN tables or using suitable MPN informatic programs. This method can be applied to drinking water and bathing water (fresh or marine), together with other similar water types including those containing an appreciable amount of suspended matter, and allows the detection of enterococci at 1 colony-forming unit (CFU) per 100 ml with definitive results within (26 ± 2) h in the presence of heterotrophic bacteria in numbers as high as 1 × 10 6 per 100 ml of sample. For bathing waters, fresh and marine, enterococci are best enumerated when samples are diluted 1:10. The test specified in this document relies upon the detection of intestinal enterococci based upon expression of the enzyme ß-D-glucosidase and provides a confirmed result in 24 h without further testing of positive wells. This document does not apply to bottled waters, for which the method has not been validated and therefore is outside the scope of this document, unless appropriate validation of performance of this method has been undertaken by the laboratory prior to use.
英文名称Water quality — Enumeration of intestinal enterococci — Part 3: Most probable number method