HiMedia – M1850 HiColiform™ Broth, Modified

Principle and Interpretation
HiColiform™ Broth, Modified was designed for detection and confirmation of Escherichia coli and total coliforms from water samples using a combination of chromogenic and fluorogenic substrates. Escherichia coli can be distinguished from other coliforms by its unique ability to fluoresce in the presence of fluorogenic substrate (1, 2). The fluorogenic substrate is split by enzyme b-glucuronidase especially present in Escherichia coli. The reaction is indicated by the development of a blue fluorescence under UV light. The presence of total coliforms is indicated by blue-green colourations due to the cleavage of the chromogenic substrate. IPTG amplifies enzyme synthesis and increases the activity of b -galactosidase. Peptone provides essential growth nutrients and is useful for the simultaneous detection of indole production. The phosphate salts provide buffering action for rapid growth of coliforms. Sodium chloride helps to maintain the osmotic balance. Sodium lauryl sulphate makes the medium selective by inhibiting accompanying microflora, especially the gram-positive organisms.

原理與解釋
HiColiform™Broth，Modified用於使用生色和熒光底物的組合檢測和確認水樣中的大腸桿菌和總大腸桿菌。 通過其在熒光底物（1,2）存在下發熒光的獨特能力，可以將大腸桿菌與其他大腸桿菌區分開來。熒光底物被特別存在於大腸桿菌中的酶b-葡醣醛酸糖苷酶分開。通過在UV光下產生藍色熒光來指示反應。總大腸菌群的存在由藍綠色表示，因為它的裂解 髮色底物。 IPTG擴增酶合成並增加β-半乳糖苷酶的活性。 蛋白腖提供必需的生長營養素，可用於同時檢測吲哚的產生。磷酸鹽為大腸桿菌的快速生長提供緩衝作用。氯化鈉有助於維持滲透平衡。十二烷基硫酸鈉通過抑制伴隨的微生物群，特別是革蘭氏陽性生物，使培養基具有選擇性。