Lab Practical 2

Question 1

Oxidase test

What color is positive for oxidase?

Answer 1

Blue or purple within 15 seconds

Question 2

Oxidase test

2 organisms used?
What was + and -?

Answer 2

*pseudomonas aeruginosa (+)
*escherichia coli (-)

Question 3

Hydrolysis of starch

What color indicates positive for AMYLASE?

What color indicates negative?

Answer 3

(+) Iodine color around streak (showed yellow on lab)

(-)dark purple around streak

Question 4

Hydrolysis of starch

What bacteria were used for test?

What was + and -?

Answer 4

Escherichia coli was (-)

Bacillus spizizenii (-)

Question 5

Hydrolysis of gelatin

What indicates positive and negative appearance of gelatinase?

Answer 5

Liquid gelatin medium/tube (+)

Solid gelatin medium/tube (-)

Question 6

Hydrolysis of gelatin

What bacteria were used and what was + and - for gelatinase ?

Answer 6

Bacillus spizizenii (+)

Escherichia coli (-)

Question 7

Detection of catalase

What indicates a positive and negative appearance?

Answer 7

bubble (+)

No bubble (-)

Question 8

Detection of catalase

What organisms were used and what was + and -?

Answer 8

Staphylococcus aureus (+)

Streptococcus equisimilis (-)

Question 9

Hydrolysis of urea

What colors indicate positive and negative appearance ?

What is produced for +?

Answer 9

Positive is hot pink

Negative is yellow/orange

Urease

Question 10

Hydrolysis of urea

What is the indicator used ?

Answer 10

Phenol red

Question 11

Hydrolysis of urea

What organisms were used and what is + and -?

Answer 11

Proteus mirabilis (+)

Escherichia coli (-)

Question 12

Fermentation of carbohydrates

What indicates a positive and negative appearance or no change ?

Answer 12

Positive is YELLOW indicating acid

BUBBLE indicates positive for gas

Negative is PINK (basic) or red indicating no change

Question 13

Fermentation of carbohydrates

What 4 types of carbohydrates can be used ?

Answer 13

Glucose

Sucrose

Lactose

Mannitol

Question 14

Fermentation of carbohydrates

What 3 organisms were used and what were the results ?

Answer 14

Escherichia coli (+) for acid and gas

Alcaligenes faecalis (-) no change

Staphylococcus aureus (+) for acid only , no gas

Question 15

S. I. M.

What does this test for ?

Answer 15

Sulfur- (production of hydrogen sulfide)

Indole- (production of indole)

Motility-(ink dictation of organism motility)

Question 16

What indicates positive appearance for S.I.M. Test ?

What reagent used for (I)?

Answer 16

(S) - black precipitate (iron sulfide)

(I) - red reagent layer (Kovacs reagent)

(M)- turbidity / spreading away from stab line

Question 17

S.I.M. Test

What organisms were used and which were positive ?

Answer 17

Escherichia coli S(-), I(+), M(+)

Citrobacter Freundii S(+), I(-), M(+)

Question 18

MRVP

Positive and negative appearance for test?

Answer 18

Red (+)

Yellow (-)

Question 19

MRVP

What 2 bacteria were used and which is - and +?

Answer 19

Enterobacter aerogenes (-) for MR, (+) for VP

Escherichia Coli (+) for MR, (-) for VP

Question 20

MRVP

What are the indicators for MR and VP?

Answer 20

MR - methyl red

VP - VP A & B

Question 21

SImmons citrate test

What colors are positives and negative?

Answer 21

Blue is (+)
Green is (-)

Question 22

Simmons citrate test

What organisms were used and what results ?

Answer 22

Escherichia coli (-)

Enterobacter aerogenes (+)