Sterile Analysis Lab Report Sample

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The lab instructor issued out a test tube labeled with letter ‘I’, which consisted of two unknown bacteria, Gram-positive or Gram-negative that were streaked from a pure culture. Sterile techniques were followed while performing precise instructions as stated in the referenced Laboratory Manual.
Example 1: The first procedure performed was done by isolating a pure culture from the mixture onto a solid Trypticase soy agar (TSA) media. Sterile technique was done by flaming the loop until it turned red to ensure that there were no current bacteria on the loop avoiding contamination followed by rapidly flaming the neck of the test tube to prevent the entry and contamination of unwanted microbes. After inoculating the loop substance from the test tube labeled ‘I’ was removed. The streak plate
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Next reflame the loop, then return to the TSA turning it at 90 degree angle while streaking quadrant two dragging some of the substance from quadrant one. Follow the same steps until all three quadrants are completed, but avoid entering quadrant one only take from quadrant two. The purpose of the streak plate method is to produce isolated colonies of an organism. The TSA plate was incubated for approximately 48 hours at 37 degrees simply to grow bacteria. After returning back to the laboratory and noticing growth on the TSA plate the same streak plate method was applied to the MacConkey agar and the Mannitol salt agar. All three plates were studied, a gram stain was performed according to the referred laboratory manual noting their color and morphology, which was recorded in the journal. Gram-positive purple coccus bacteria and gram-negative rod/bacillus were identified using the microscope. The purpose of streaking on the MacConkey is to see if gram negative is lactose fermented or not and on the Mannitol salt agar if gram positive microorganism is able to ferment sugar. There were two types of bacteria that grew on the nutrient agar plates which were

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