Microbiology Lab Fall 2012

Fermentation Tubes and Plates

Group 2 Fermentation Tubes 1 Group 2 Agar Plate Group 2 Membrane Filter

Table 1 – Number and Description of Colonies

Table # _____2_______

Names __Yong Wu,   Julio Huerta,   Jason Bettencourt,   Emmanuel Ortiz                    

Water Analysis Data Collection

Glucose fermentation tubes

Tube ID

(Dilution 1:2)

Media Description

(color, turbidity,

sediment, etc)

Presence or absence

of gas

On a scale of 1 – 5 describe the transparency of the media

1 (1:1)

Cloudy  

2

2 (1:2)

Clear Yes, because there are bubbles in the tube.  

4

3 (1:4)

Clear  

4

4 (1:8)

Clear  

5

5 (1:16)

Clear  

4

6 (1: 48)

Clear

 

5

7 ( 1: 144)

 

Clear

 

5

8 (1:432)

 

 

Enumeration and Description of Colonies on Nutrient Agar Plates and Membranes

Plate ID

Total Number of Colonies

Number of Different Colonies

Other Observations/Comments

 

Coliforms/100 mL

Nutrient agar Plates

31

7

Had some yellow colonies around. Fermentation occurred.

310

Membrane Filtration

(Dilution 1:2)

100

5

none

1000

How to calculate the number of coli form per 100 mL of sample

Coliform/100mL = (Number of colonies counted) X 100/(Sample Size, (10) mL)