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Author Topic: How do I identify bacteria in a product?  (Read 3835 times)

Offline nikki

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How do I identify bacteria in a product?
« on: 30/05/2013 02:36:16 »
I have a product that is a mixture of enzymes and sugar coated bacteria. What is the best way to start sourcing the enzymes and bacteria in the mixture...

Can any one please suggest some Tests to confirm
« Last Edit: 30/05/2013 16:25:32 by chris »


 

Offline CliffordK

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Re: Bacterial Identification
« Reply #1 on: 30/05/2013 06:10:12 »
Sugar Coated Bacteria? 
Keep in mind that with your processing, assuming you are wanting the bacteria, then you won't want to kill them.  Many organisms don't like pure sugar/syrup (thus one can keep sugar & syrup without refrigeration).  And, of course, heat may also kill your bacteria.

Some bacteria may be generally specific to the product.  For example Sourdough may contain a mixture of yeast and lactobacilli.

Yogurt is also produced using a variety of bacteria. 

You may get cultures from cheese manufacturing too.  It all depends on your goals.

I haven't done much bacteria identification.  You should be able to get general identification by culturing it on a variety of agars, as well as doing a gram stain and looking at the bacteria under a microscope (generally quite a powerful microscope).

You may look into ways to grow your bacteria, so once you get the initial cultures, you can keep growing more, without needing to purchase more.

Everything depends on what your ultimate goal is.  You may be able to order some organisms from lab supply stores too.
 

Offline evan_au

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Re: Bacterial Identification
« Reply #2 on: 30/05/2013 16:45:00 »
If there are bacteria present, you may be able to extract DNA, and have the DNA sequenced in a lab?
  • Most bacteria coated in a water-hungry substance like sugar would shrivel up and die.
  • However, some bacteria can form resistant spores which reanimate when exposed to a wet environment.

You can separate out the sugars and enzymes by using Chromatography (sometimes coupled with mass spectrometry).

These are pretty hi-tech approaches that you can't apply to yeast in your average kitchen; and there isn't an app for that on today's smartphones...
 

Offline nikki

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Re: How do I identify bacteria in a product?
« Reply #3 on: 31/05/2013 12:06:50 »
Sorry what i meant to explain by sugar coated bacteria is that the bacteria itself has a polysaccharide encapsulation.......
 

Offline cheryl j

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Re: How do I identify bacteria in a product?
« Reply #4 on: 31/05/2013 14:16:59 »
Do you know if the bacteria in your sample is one type or is it a mixed or unknown culture? Do you need to identify all the way to the species level? For example, identifying something as a "staph species" or "strep species" or an "enteric/coliform" is relatively cheap and easy to do. If you grow bacteria on blood agar, do a gram stain, test with H202, and a bacitracin disc, you can identify  staph and strep and micrococcus. A single type of agar like Eosin-methylene blue agar can select for coliforms or gut bacteria. Some enteric agars can select for or rule out sulfur metabolizing bacteria like salmonella.

 Getting it to the species level involves a series or panel of biochemical tests, test kits that use antibody-latex agglutination, or instruments that use DNA amplification.

If you know what bacteria you are looking for, and just want to confirm that it is there, or not there, that greatly simplifies things, (and I would assume that is true for chemical analysis as well.)

If you are looking for the presence of one particular kind of microorganism, you could use a microscope, gram stain (assuming you have access) and selective agar to select for or rule out certain types, and then send your pure culture of the organism to a lab for final identification/speciation. This would be a lot cheaper than asking them to identify anything or everything that is there.
« Last Edit: 31/05/2013 14:49:45 by cheryl j »
 

Offline CliffordK

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Re: How do I identify bacteria in a product?
« Reply #5 on: 31/05/2013 19:56:54 »
There are, of course, tests like the Rapid Strep Test which probes for streptococcus antigens.  Since it is mass produced, the test is relatively cheap.

Presumably a similar test could be designed to probe for any specific bacteria, and perhaps viruses too.
 

Offline cheryl j

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Re: How do I identify bacteria in a product?
« Reply #6 on: 01/06/2013 01:44:19 »
There are, of course, tests like the Rapid Strep Test which probes for streptococcus antigens.  Since it is mass produced, the test is relatively cheap.

Presumably a similar test could be designed to probe for any specific bacteria, and perhaps viruses too.

The Rapid Strep test only tests for group A strep, though. There are rapid antigen tests for Neisseria meningitidis, N. gonnorhoeae, Salmonella typhi, Ecoli 0157, rotavirus, influenzae, and malaria. Probably others.
 

Offline distimpson

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Re: How do I identify bacteria in a product?
« Reply #7 on: 01/06/2013 13:09:45 »
There may some lost in translation going on here so just guessing. Bacteria and enzymes in a product bring to mind natto, a fermented soy bean dish. The bacteria is Bacillus subtilis var natto, the fermentation product contains, among other things, nattokinase which is believe to have health benefits. It is a popular breakfast dish in Japan although many find it offensive due to the smell. You can make your own, the starter is available, did this a few times for a natto “fix” in the middle of Kansas but it was never the same as in Japan. You can propagate the B. subtilis using soy bean mashed up with agar in a petri dish, also helps to determine if anything else is growing as most bacterial colonies have a very unique pattern. Came mind after yesterday's Google home page: “Google turned its homepage into a living petri dish today in honor of the 161st birthday of Julius Richard Petri, the German microbiologist who developed the technology.“

To test for enzyme activity you usually monitor the change of a substrate or substrate analog, need more details to say much more than this.

Just woke up, hope this isn't too incoherent :-)
 

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Re: How do I identify bacteria in a product?
« Reply #7 on: 01/06/2013 13:09:45 »

 

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