Microbiology: An Introduction
Microbiology: An Introduction
12th Edition
ISBN: 9780321929150
Author: Gerard J. Tortora, Berdell R. Funke, Christine L. Case
Publisher: PEARSON
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Chapter 6, Problem 3CAE

The number of bacteria in saliva samples was determined by collecting the saliva, making serial dilutions, and inoculating nutrient agar by the pour plate method. The plates were incubated aerobically for 48 hours at 37°C.

  Bacteria per ml Saliva
  Before UsingMouthwash After UsingMouthwash
Mouthwash 1 13.1 × 106 10.9 × 106
Mouthwash 2 11.7 × 106 14.2 × 105
Mouthwash 3 9.3 × 105 7.7 × 105

What can you conclude from these data? Did all the bacteria present in each saliva sample grow?

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The number of bacteria in saliva samples was determined by collecting the saliva, making serial dilutions, and inoculating nutrient agar by the pour plate method. The plates were inoculated aerobically for 48 hours at 37°C. What can you conclude from this data? Why?   Mouthwash CFU per ml in salvia                             Before Use         After Use Listerine 2.22 x 107             1.22x107   Schmidts Mouthwash 2.42 x 107        3.22x105   Biotene Mouthwash 3.21 x 107         2.12 x106
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Microbiology: An Introduction

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