Method and medium for use in detecting target microbes in situ in a specimen sample of a possibly contaminated material

A specific medium for addition to a specimen sample of a material suspected to be contaminated with E. coli to determine the presence or absence of E. coli in the specimen sample, and which can detect the presence of E. coli without the need of performing a preliminary E. coli growth step, said medium comprising operative amounts of essential vitamins and elements needed to support growth of E. coli and a chromogenic substrate for .beta.-glucuronidase enzyme which is substantially the sole carbon source nutrient in the medium and which is metabolizable by E. coli to the extend needed to support continued reproductive growth thereof, and which, when metabolized, releases a chromogen which alters the color of the specimen there being no other nutrients in the medium which are able to support substantial reproductive growth of E. coli in the sample.

A specific medium for addition to a specimen sample of a material suspected to be contaminated with gram negative bacteria to determine the presence or absence of gram negative bacteria in the specimen sample, and which can detect the presence of gram negative bacteria without the need of performing a preliminary gram negative bacteria growth step, said medium comprising operative amounts of essential vitamins and elements to support growth of gram negative bacteria, effective amounts of antibiotic material operable to render any yeast and gram positive bacteria in the specimen sample incapable of metabolizing nutrients, and a nutrient chromogenic substrate for L-alanine aminopeptidase which is substantially the sole carbon source nutrient in the medium and which is metabolizable by gram negative bacteria to the extend needed to support continued reproductive growth thereof, and which, when metabolized, releases a chromogen which alters the color of the specimen there being no other nutrients in the medium which are able to support substantial reproductive growth of gram negative bacteria in the sample.

A specific medium for addition to a specimen sample of a material suspected to be contaminated to determine the presence or absence of a target microbe in the specimen sample, and which can detect the presence of said target microbe without the need of performing a preliminary target microbe growth step, said medium comprising operative amounts of essential vitamins and elements needed to support growth of said target microbe and a nutrient-indicator which is the primary nutrient in the medium and which is substantially the only nutrient in said medium which can be metabolized by said target microbe to the extent needed to support continued growth thereof, and, which cannot be metabolized by other viable microbes in the specimen to that extend, said nutrient-indicator including a metabolizable moiety and a sample-altering moiety the latter of which is released only when said nutrient-indicator is metabolized by said target microbe, whereupon a sensible characteristic of the sample is altered, said medium being in the form of a non-sterile, water-soluble powder.

A specific medium for the detection of a target micro-organism in a sample, and which can detect the presence of said target micro-organism without the need of performing a preliminary target micro-organism growth step, said medium comprising a two component mixture, a first component of which includes a combination of elements, vitamins and other essential nutritive materials required to support growth of the target micro-organism but said first component being unable by itself to allow substantial reproductive growth of the target micro-organism or any other viable organism in the sample;

• and a second component which comprises a primary nutrient ingredient, which is present in operative amounts to allow substantial growth of only the target micro-organism, said ingredient being in the form of a coupled nutrient-indicator such that when the nutrient is metabolized by the target micro-organism, a sensible characteristic of the sample is altered there being no other nutrients in the medium which are able to support substantial reproductive growth of the target micro-organisms in the sample.

A specific medium for combination with a specimen sample of a material to detect total coliforms in the sample, said medium comprising:

• operative amounts of vitamins and elements needed to support growth of total coliforms;
• and a nutrient-indicator which is the primary source of metabolizable carbon in the medium for total coliforms and which is a nutrient which cannot be metabolized by other viable microbes in the sample to the extend needed to support continued reproductive growth of said other viable microbes, said nutrient indicator, when metabolized, producing a visible color change in the specimen, and said nutrient indicator being a substrate for .beta.-galactosidase there being no other nutrients in the medium which are able to support substantial reproductive growth of total coliforms in the sample.

A non-sterile, water soluble powdery specific medium for determining the presence or absence of a target microbe in a specimen sample of water suspected to be contaminated, and which can detect the presence of said without the need of performing a preliminary target microbe growth step, said medium comprising about 10% to about 50% by weight of a nitrogen-containing compound, about 0.06% to about 1.0% by weight of amino acids essential to growth of said target microbe, about 0.09% to about 0.60% by weight of vitamins essential to growth of said target microbe, about 0.05% to about 0.70% by weight of elements essential to growth of said target microbe, about 6.4% to about 85% by weight of salts essential to growth of said target microbe, and about 1.20% to about 2.0% of a nutrient-indicator which is substantially the sole carbon source nutrient in the medium and which is the only nutrient in said medium which can be metabolized by said target microbe to the extent needed to support continued reproductive growth thereof and which is a nutrient which cannot be metabolized by other viable microbes in the sample to that extent, said nutrient-indicator, when metabolized by said target microbe, releasing a moiety which will alter a sensible characteristic of the sample.