Test

Picture

Result

Description

OF Medium

Tube with Oil (anaerobic):

Reaction: positive

Color: yellowish

pH: acidic conditions

Metabolic reaction: Glucose wasn’t breaking down for the tube without oil, but it was broken down for the tube with oil meaning that the bacteria was able to fermentatively metabolize glucose.

Enzymatic activity: Not applicable.

Other: The unknown bacteria is anaerobic.

Tube without Oil (aerobic):

Reaction: negative

Color: green

pH: oxidative

Kligler’s Triple Iron Agar

Reaction: — positive/negative?

Positive

Color: red slant and yellowish butt.

pH: acidic

Other: No gas and no H2S present

Metabolic reaction: Glucose is only breaking down (fermented)

Enzymatic activity:

Other: The yellow color at the but is super light but it differentiates.

Litmus Milk

Reaction: — positive/negative?

positive

Color: blue

pH: alkaline (basic)

Other: Casein was breaking down into smaller components

Metabolic reaction: Protein casein was metabolized

Enzymatic activity: Lactose wasn’t fermented.

Other: Unknown bacterial utilized milk components to metabolize.

Nitrate Reduction

Reaction: — positive/negative?

Positive

Color didn’t change

Color: no color change

pH: basic

Other: color looks light/clear yellowish

Metabolic reaction: Nitrates have been broken down.

Enzymatic activity: Nitrates are not in the solution

Other: Bacteria didn’t break down nitrates into nitrites. Zinc was added.

Gelatin Hydrolysis

Reaction: — positive/negative?

Negative

Color: light/clear yellow

pH: acidic

Other: Stay solid even after ice bath.

Metabolic reaction: No liquefaction occurred meaning that gelatin wasn’t removed.

Enzymatic activity: Gelatinase didn’t break down gelatin.

Other: Gelatin wasn’t removed

Urease

Reaction: — positive/negative?

Positive

Color: pink agar- clear bacteria

pH: alkaline (basic)

Other: Can’t even differentiate between the colonies and the agar.

Metabolic reaction: Urea was broken down by urease

Enzymatic activity: Urea was broken down by urease enzyme

Other: Ammonia formation

Starch Hydrolysis

Reaction: — positive/negative?

Positive

Color: purple in agar and yellowish in the bacteria colonies.

pH: acidic

Other: after a while colony turned whiter.

Metabolic reaction: Iodine turned purple in the presence of starch.

Enzymatic activity: alpha amylase hasn’t break down starch because still present in the agar plate.

Methyl Red (48 hours)

Reaction: — positive/negative?

negative

Color: yellow

pH: basic

Metabolic reaction: No fermentation was used

Enzymatic activity: No dextrose/glucose was broken down into pyruvate

Other: Used to test metabolic pathway (fermentation specifically)

Voges-Proskauer (48 hours)

Reaction: — positive/negative?

Negative

Color: no color change

pH: basic

Metabolic reaction: Glucose was not fermented using the 2,3 butanediol pathway.

Enzymatic activity:

Acetoin is not preset.

Other: no glucose fermented

Catalase

Reaction: positive/negative?

Positive

Color: white

pH: alkaline (basic)

Other: catalase present

Metabolic reaction: Reaction is positive because hydrogen peroxidase was broken down into water and oxygen.

Enzymatic activity: catalase was present

Other: Bacteria utilizes catalase enzyme.

Oxidase

Reaction: — positive/negative?

Negative

Color: no color change

pH: acidic

Metabolic reaction: Bacteria didn’t produce or utilized Cytochrome-C

Enzymatic activity: No Cytochrome-C present because bacteria didn’t change color.