Modification of the H2S test to screen for the detection of sulphur- and sulphate-reducing bacteria of faecal origin in water

The H2S test was created to assess the microbial quality of drinking water in low-resource settings, but the original version of the H2S test lacks sensitivity and specificity for faecal indicator bacteria. There is evidence that a modified media formula of the H2S test may be more sensitive and spe...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Bastian Schnabel, Jonathan Lance Caplin, Ian Richard Cooper
Formato: article
Lenguaje:EN
Publicado: IWA Publishing 2021
Materias:
Acceso en línea:https://doaj.org/article/6270b4b13d334b0ab9f8025abf1b7fa6
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
Descripción
Sumario:The H2S test was created to assess the microbial quality of drinking water in low-resource settings, but the original version of the H2S test lacks sensitivity and specificity for faecal indicator bacteria. There is evidence that a modified media formula of the H2S test may be more sensitive and specific for the faecal indicator bacterium Escherichia coli (E. coli) and less sensitive to organisms of non-faecal origin. This research established the detection threshold and operational range of the H2S test, to increase its sensitivity and specificity for E. coli. A total of 20 modifications of the H2S test, and the original test, were assayed against 20 confirmed and pure culture bacteria of faecal and non-faecal origin at varying concentrations. Additionally, some of the H2S test modifications were evaluated against standard methods for drinking-water analysis. Results indicate that using a modified version of the H2S test containing L-cystine and 2-mercaptopyridine, and bile salts or penicillin G, E. coli will produce H2S. In addition, this research reveals which organisms react positively to the original and modified versions of the H2S test. The modified versions of the H2S test can be promoted as a simple screening test for microbial drinking-water safety in low-resource settings.