Method for detecting a Shigella or Cronobacter microorganism

Patent metadata

Field	Value
Publication number	US-10619181-B2
Application number	US-201816035758-A
Country	US
Kind code	B2
Filing date	Jul 16, 2018
Priority date	Dec 30, 2010
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

A method of detecting a Shigella or Cronobacter microorganism. The method comprises providing a culture device with a selective culture medium and a detection article comprising a first indicator system.

First claim

The invention claimed is:

1. A method of detecting a Shigella or Cronobacter microorganism, comprising the steps of:
(a) providing:
(i) a culture device including a culture medium comprising ingredients selected to facilitate growth of an Enterobacteriaceae microorganism;
(ii) a detection article comprising a first indicator system, the first indicator system selected to detect the Shigella or Cronobacter microorganism;
wherein the Shigella or Cronobacter microorganism is detected by its ability to convert the first indicator system from a first state to a second state; and

(iii) a sample;

(b) inoculating the culture device with the sample;
(c) incubating the inoculated culture device for a period of time sufficient to permit growth of indicator microorganisms;
(d) observing the culture device for an indication of a presence of at least one indicator microorganism;
(e) contacting the culture medium of the incubated culture device with the first indicator system of the detection article; and

observing the article-contacted culture device to detect a conversion of the first indicator system from a first state to a second state, wherein the conversion of the first indicator system from the first state to the second state is indicative of the presence of at least one Shigella or Cronobacter microorganism.

2. The method of claim 1 , wherein the genus is Shigella and the first indicator system comprises a reagent to detect β-glucosidase, β-fucosidase, N-acetyl-β-galactosaminidase, or a combination of any two or more of the foregoing enzyme activities.

3. The method of claim 1 , wherein the genus is Cronobacter and the first indicator system comprises a reagent to detect α-glucosidase activity, β-cellobiosidase enzyme activity, or both.

4. The method of claim 1 , wherein providing the culture device further comprises providing a culture device that comprises a hydrogel or a dry, cold water-soluble gelling agent.

5. The method of claim 1 , wherein observing the culture device or the article-contacted culture device comprises visual observation.

6. The method of claim 1 , wherein observing the culture device or the article-contacted culture device comprises observation using an imaging device.

7. The method of claim 1 , wherein contacting the culture medium with the detection article further comprises contacting the culture medium with the detection article at a predetermined temperature.

8. The method of claim 1 , further comprising enumerating Shigella microorganisms in the culture device.

9. The method of claim 1 , further comprising enumerating Cronobacter microorganisms in the culture device.

10. The method of claim 1 , wherein the detection article comprises a substrate with upper and lower major surfaces and a coating comprising the first indicator system disposed on at least one of the major surfaces.

11. The method of claim 10 , wherein the first indicator system is coated on both major surfaces.

12. The method of claim 10 , wherein the substrate is selected from the group consisting of a polymeric film, paper, a nonwoven, a membrane filter and derivatives of any of the foregoing.

13. The method of claim 11 , wherein the coating comprises a binder.

Assignees

• 3M Innovative Properties Co

Inventors

• Moriyama Takatoshi
• Mach Patrick A
• Kitahara Akio
• Lubrant Henry J

Classifications

• C12Q1/34

  involving hydrolase · CPC title

• C12Q1/04 Primary

  Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor {(C12Q1/6897 takes precedence)} · CPC title

• C12Q1/44

  involving esterase · CPC title

• C12Q1/10

  Enterobacteria · CPC title

• C12Q1/22

  Testing for sterility conditions · CPC title