Detection of acid-producing bacteria

Patent metadata

Field	Value
Publication number	US-9873904-B2
Application number	US-201414493991-A
Country	US
Kind code	B2
Filing date	Sep 23, 2014
Priority date	Jun 15, 2009
Publication date	Jan 23, 2018
Grant date	Jan 23, 2018

Abstract

The disclosure provides culture devices and methods useful for detecting acid-producing bacteria in a sample. The devices include a nutrient medium and a pH indicator to detect and differentiate acid-producing microorganisms, such as lactic acid bacteria. Methods of use include detecting or enumerating acid-producing microorganisms. The methods further provide for the detection of gas-producing acid-producing bacteria.

First claim

What is claimed is:

1. A method comprising:
providing a thin film culture device comprising a culture medium to support growth of acid-producing bacteria and a cold water-soluble gelling agent, a carbohydrate that can be fermented by the acid-producing bacteria, a sample, and a pH indicator with a transition range that extends below pH 7.0;
combining, in the culture device, a predetermined volume of the sample,the culture medium, the pH indicator, and the fermentable carbohydrate;
incubating the culture device for a period of time; and
detecting the presence or absence of a microorganism;
wherein detecting the presence or absence of a microorganism comprises detecting the presence or absence of an acid-producing microorganism.

2. The method of claim 1 , wherein the pH of the culture medium in the provided thin film culture device is less than 6.5.

3. The method of claim 1 , wherein the provided thin film culture device further comprises a selective agent.

4. The method of claim 3 , wherein the selective agent is an antifungal agent.

5. The method of claim 4 wherein the antifungal agent is selected from the group consisting of Cycloheximide, Nystatin, Natamycin, Amphotericin B, Filipin, and combinations thereof.

6. The method of claim 1 , further comprising differentiating the acid-producing bacteria, wherein said differentiating comprises detecting production of carbon dioxide gas by individual colonies.

7. The method of claim 1 , wherein said incubating is carried out aerobically.

8. The method of claim 1 , wherein said incubating is carried out anaerobically.

9. The method of claim 1 , further comprising combining the sample with a diluent capable of neutralizing a chemical sanitizer.

10. The method of claim 1 , further comprising:
providing an imaging system; and
obtaining an image of a growth area of the culture device;
wherein said detecting comprises displaying, printing, or analyzing the image of the growth area.

11. The method of claim 10 , wherein the imaging system comprises an illumination source and wherein said obtaining comprises illuminating the growth area.

12. The method of claim 1 , further comprising the step of enumerating microorganisms.

13. The method of claim 12 , wherein said enumerating microorganisms comprises enumerating two or more types of microorganisms.

14. The method of claim 1 wherein the pH indicator is bromcresol purple, bromphenol blue, chlorophenol red, or bromcresol green.

15. The method of claim 1 wherein the acid-producing bacteria is Acetobacter or a lactic acid-producing bacteria.

Assignees

• 3M Innovative Properties Co

Inventors

• Young Robert F
• Mach Patrick A
• Hughes Michael E
• Binsfeld Christine A
• Bjork Jason W
• Celt Mara S
• Lubrant Henry J

Classifications

• 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

• C12M23/34

  Internal compartments or partitions · CPC title

• C12M23/04

  Flat or tray type, drawers (C12M23/10, C12M23/12, C12M23/16 take precedence) · CPC title

• C12M23/20

  Material Coatings (immunocoatings C12M25/00) · CPC title

• C12M25/06

  Plates; Walls; Drawers; Multilayer plates · CPC title