水质.去硝假单胞菌的检测及计数.第2部分:最可能数法

[中文适用范围]： 本文件规定了水中铜绿假单胞菌的计数方法。 该方法基于目标生物体在液体培养基中的生长，并参考 MPN 表计算生物体的最可能数 (MPN)。 本文件适用于多种类型的水。 例如，医院用水、饮用水和供人类饮用的非碳酸瓶装水、地下水、游泳池和温泉池水，包括含有高背景异养细菌计数的水。 本文件不适用于碳酸瓶装水、调味瓶装水、冷却塔水或海水，因为该方法尚未经过验证。 因此，这些水域不属于本文件的讨论范围。 实验室可以在使用前对该方法的性能进行适当的验证，从而将本文件中介绍的方法用于这些基质。 该测试基于细菌酶检测技术，通过特殊试剂中存在的 7-氨基-4-甲基香豆素氨肽酶底物的水解来发出铜绿假单胞菌存在的信号。 铜绿假单胞菌细胞利用试剂中丰富的氨基酸、维生素和其他营养物质快速生长和繁殖。 活跃生长的铜绿假单胞菌菌株具有一种酶，可以裂解 7-酰胺基香豆素氨肽酶底物，释放出在紫外 (UV) 光下发出荧光的产物。 本文件中描述的测试可在 24 小时内提供确认结果，无需进一步确认阳性孔。 [外文原描述]： This document specifies a method for the enumeration of Pseudomonas aeruginosa in water. The method is based on the growth of target organisms in a liquid medium and calculation of the most probable number (MPN) of organisms by reference to MPN tables. This document is applicable to a range of types of water. For example, hospital waters, drinking water and non‑carbonated bottled waters intended for human consumption, groundwater, swimming pool and spa pool waters including those containing high background counts of heterotrophic bacteria. This document does not apply to carbonated bottled waters, flavoured bottle waters, cooling tower waters or marine waters, for which the method has not been validated. These waters are, therefore, outside the scope of this document. Laboratories can employ the method presented in this document for these matrices by undertaking appropriate validation of performance of this method prior to use. The test is based on a bacterial enzyme detection technology that signals the presence of P. aeruginosa through the hydrolysis of a 7‑amino‑4‑methylcoumarin aminopeptidase substrate present in a special reagent. P. aeruginosa cells rapidly grow and reproduce using the rich supply of amino acids, vitamins and other nutrients present in the reagent. Actively growing strains of P. aeruginosa have an enzyme that cleaves the 7‑amido‑coumarin aminopeptidase substrate releasing a product which fluoresces under ultraviolet (UV) light. The test described in this document provides a confirmed result within 24 h with no requirement for further confirmation of positive wells.