Methods Of Identification Culture Method

Question 1

provides the appropriate
biochemical and biophysical environment for microbial growth

Answer 1

CULTURE MEDIA

Question 2

COLONY
Types:

Answer 2

• Mucoid colony
• Smooth colony
• Rough colony

Question 3

Culture
•Types:

Answer 3

pure, mixed, stock

Question 4

TYPES OF CULTURE MEDIA
Based on:

Answer 4

• Physical Form / Consistency
• Composition
• Function / Purpose
• Distribution

Question 5

Physical Form:

• water- based
• broth, milk, infusion

Answer 5

LIQUID MEDIA

Question 6

Liquid media

Positive growth

Answer 6

dispersed
cloudy
turbidity
particulate appearance

Question 7

Physical Form:
SEMI - SOLID MEDIA

with solidifying agent ______

• detects bacterial motility

Answer 7

0.3 - 0.5% Agar

Question 8

Semi-Solid

Examples:
@___________
@_____= detects H2S& indole production

Answer 8

Motility test medium

SIM

Question 9

Physical Form:
SOLID MEDIA

• allows growth of discrete colonies
@_______ agar

Answer 9

1-5% Agar

Question 10

SOLID MEDIA

LIQUEFIABLE

NON - LIQUEFIABLE

Answer 10

• NA, MacConkey

• Middlebrook 7H11
•Lowenstein - Jensen media

Question 11

Composition:

• chemically defined

Answer 11

SYNTHETIC MEDIA

Question 12

Composition:

• complex media

Answer 12

NON-SYNTHETIC MEDIA

Question 13

• at least one of the ingredients is not chemically defined
• for cultivation of bacterial pathogens & fastidious bacteria

Answer 13

NON-SYNTHETIC MEDIA

Question 14

Anaerobic Growth
Anaerobic bacteria requires:

Answer 14

• Low oxygen content
• Reduced oxidation-reduction potential
• Extra nutrients

Question 15

Anaerobic media examples

Answer 15

•Anaerobic PEA
•Anaerobic KV Thioglycollate broth
•Robertson Cooked Meat = bullock heart meat

Question 16

• maintains viability of bacteria and slows rate of reproduction

Answer 16

Transport Media

Question 17

Transport media purpose

Answer 17

Purpose:
1. Prevents drying / desiccation of specimen
2. Inhibit overgrowth of unwanted bacteria

Question 18

TRANSPORT MEDIA

Answer 18

STUART’S (1954)

AMIES (1965)

CARY BLAIR (1964)

BUFFERED GLYCEROL SALINE

Question 19

• Maintains original state of specimen
• with charcoal-impregnated swabs & glycerophosphate in medium

Answer 19

STUART’S (1954)

Question 20

• Replace glycerophosphate w/ balanced salt soln
• charcoal is incorporated into medium

Answer 20

AMIES (1965)

Question 21

• pH increased from 7.4 to 8.4
• No charcoal
• Recommended for fecal specimens suspicious for Campylobacter sp

Answer 21

CARY BLAIR (1964)

Question 22

• Good for mailing fecal specimens
• High ph to favor fecal pathogens
• Not for transport of fecal specimens suspected to be
Campylobacter sp (+)

Answer 22

BUFFERED GLYCEROL SALINE

Question 23

Functional Type:

• for the assay of vitamins, amino acids and antimicrobial agents.
• to monitor the effects of the administration of certain antimicrobial drugs.

Answer 23

Assay Media

Question 24

Assay Media example

Answer 24

Mueller Hinton Agar

Question 25

Functional Type: • Used by industrial and environmental microbiologists to count the number of organisms in milk, water, food, soil and other samples.

Answer 25

Enumeration Media

Question 26

Potato-Dextrose Agar

Answer 26

Enumeration media

Question 27

Measurement of Cell Numbers

Answer 27

1.Direct microscopic counts 2. Electronic counting chambers 3. Indirect viable cell counts

Question 28

Distribution: TUBED

Answer 28

• Butt • Slant •Slant/Butt

Question 29

METHODS OF OBTAINING PURE CULTURE

Answer 29

A. STREAK PLATE B. POUR PLATE C. SELECTIVE METHOD D. ANIMAL INOCULATION

Question 30

PLATED MEDIA

Answer 30

QUADRANT STREAK CONTINUOUS STREAK RADIANT STREAK

Question 31

Preserving Bacterial Cultures • Deep-freezing:

Answer 31

-50° to -95° C

Question 32

Preserving Bacterial Cultures • Lyophilization:

Answer 32

Frozen (-54° to -72° C) then vacuum-dehydrated