METHOD AND SYSTEM FOR RAPID DETECTION OF LOW LEVEL BACTERIA IN A GROWTH MEDIUM

Abstract

The disclosure is directed at a system and method for rapid detection of low level bacteria in a growth medium. The method is directed at a two-stage process whereby a growth medium is incubated along with a first test formulation component for a predetermined period of time. After the incubation period, a second test formulation component is added to the growth medium to determine if there is a bacteria in the growth medium.

Description

Claims

1. A method of detection of low level bacteria in a growth medium sample comprising: adding a selective chromogenic substrate to the growth medium sample;incubating the growth medium sample for a predetermined period of time; andadding a dye reagent to the growth medium sample;wherein if a color change in the growth medium sample is observed, a presence of bacteria is confirmed.

2. The method of claim 1 wherein the selective chromogenic substrate is 5-bromo-4-chloro-3-indoxyl-beta-D-glucuronide cyclohexylammonium salt (x-gluc); 1-5-Bromo- 4-Chloro-3-Indolyl Phosphate (BCIP) or 2-5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (x-gal).

3. The method of claim 1 wherein the dye reagent is nitroblue tetrazolium (NBT), tetrazolium-formazan substrates or resazurin substrates.

4. The method of claim 1 further comprising, before adding a selecting chromogenic substrate: placing an item of interest into the growth medium sample.

5. The method of claim 1 wherein adding a selective chromogenic substrate to the growth medium sample comprises: adding the selective chromogenic substrate to a liquid sample.

6. The method of claim 5 wherein adding the selective chromogenic substrate to the liquid sample comprises: adding the selective chromogenic substrate to a water sample.

7. The method of claim 1 further comprising, after adding a selective chromogenic substrate to the growth medium sample: adding nutrients to the growth medium sample to enhance bacteria growth.

8. The method of claim 1 further comprising: correlating an observed color change with a level of bacteria.

9. The method of claim 7 wherein correlating an observed color change comprises: analyzing the liquid sample with a spectrophotometer or colorimeter.

10. The method of claim 1 wherein adding a selective chromogenic substrate to the growth medium sample comprises: adding the selective chromogenic substrate to an agar gel sample.

11. A system for rapid detection of low level bacteria in a growth medium comprising: a first test formulation component that is incubated for a predetermined period of time within the growth medium for enabling bacteria enzyme growth; anda second test formulation component for adding to the incubated growth medium and first test formulation component.

12. The system of claim 11 wherein the first test formulation component comprises a selective chromogenic substrate.

13. The system of claim 12 wherein the selective chromogenic substrate comprises 5-bromo-4-chloro-3-indoxyl-beta-D-glucuronide cyclohexylammonium salt (x-gluc); 1-5-Bromo- 4-Chloro-3-Indolyl Phosphate (BCIP) or 2-5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (x-gal).

14. The system of claim 11 wherein the second test formulation component comprises a dye reagent.

15. The system of claim 14 wherein the dye reagent comprises nitroblue tetrazolium (NBT); tetrazolium-formazan substrates or resazurin substrates.

16. The system of claim 11 further comprising a set of nutrients for enhancing bacteria enzyme growth during the incubation period.

17. The system of claim 11 wherein the growth medium is in a liquid form.

18. The system of claim 11 wherein the growth medium is in a solid form.