Recommendations for Bacteria Detection?

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    • #17864
      lodestone25
      Participant

      Hi all, I apologize if this is a dumb question-I’m quite new to the biology field and to be honest at this point I’m not even sure if I’m asking the right things. I am wondering what the best way to do a field test on, say, a lake or puddle, to check the number of bacteria present in the water. I’m not as interested in particular species as I am in obtaining some idea of "bacteria density" or parts per gram. I’m not sure if it matters, but the water may be contaminated with fertilizer, soaps, etc… Is there some kind of quick test that can help me out with that? Or is the best way to get some sort of field microscope and put a sample on a glass slide? Thank you very much for your expertise!

      Lodestone

    • #115436
      Cat
      Participant

      I doubt very much that you can do it in the field. I think you need to culture and do colony counts the old fashioned way…

    • #115483
      josem
      Participant

      I think you can use a hemocytometer to count the total bacteria present in the water. But it is
      difficult to count the motile bacteria in hemocytometer. I suggest to use a disinfectant to kill the bacteria before counting.I think you can also use a stain for seeing the bacteria in the microscope.

    • #115485
      JackBean
      Participant

      Well, the standard way is to filter the water and keep the filter on some growth medium to see how many colonies will form. However, not every growth medium will suit every bacteria and some bacteria are unculturable in general. More precise way is to do 16S RNA sequencing, but I’m not sure if that tells also the amount of bacteria or only the species.

    • #115490
      SpellForce
      Participant

      If you blow your nose and do a culture, would the grown bacteria be 100% bad, or there would be also some good bacteria? 🙂

    • #115692
      Steven2015
      Participant

      There are many bacteria detection kits available on the market. Using kits will help you save a lot of works.

    • #116040
      Fornita
      Participant

      This service could also help you with your question.
      http://www.creativebiomart.net/Microbio … ervice.htm

    • #116359
      josem
      Participant
      quote josem post_id=165190 time=1412711926 user_id=269112:

      I think you can use a hemocytometer to count the total bacteria present in the water. But it is
      difficult to count the motile bacteria in the hemocytometer. I suggest using a disinfectant to kill the bacteria before counting.I think you can also use a stain for seeing the bacteria under the microscope.

      The immunofluorescence could be used in this method, in which a fluorochrome dye is linked to antibodies raised against a common outer cell wall epitopes of the prokaryotic domain. A measured volume of sample water is filtered and the resulting cells are resuspended and treated with the antibody linked dye and wash. It is then resuspended in the required volume of water, smear in an ordinary glass slide, heat fix or air dry and count the cell number. Hemocytometer is not required, actually. But it gives only approximate count because aggregated bacteria cannot be differentiated. I think agitation before staining would separate the aggregated cells.

    • #116364
      josem
      Participant
      quote josem post_id=177285 time=1522514006 user_id=269112:

      quote josem post_id=165190 time=1412711926 user_id=269112:

      I think you can use a hemocytometer to count the total bacteria present in the water. But it is
      difficult to count the motile bacteria in the hemocytometer. I suggest using a disinfectant to kill the bacteria before counting.I think you can also use a stain for seeing the bacteria under the microscope.

      The immunofluorescence could be used in this method, in which a fluorochrome dye is linked to antibodies raised against a common outer cell wall epitopes of the prokaryotic domain. A measured volume of sample water is spun and the resulting cells are resuspended and treated with the antibody linked dye and wash. It is then resuspended in the required volume of water, smear in an ordinary glass slide, heat fix or air dry and count the cell number. Hemocytometer is not required, actually. But it gives only approximate count because aggregated bacteria cannot be differentiated. I think agitation before staining would separate the aggregated cells.

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