1. Culture Techniques for Bacteriology
Lesson 7-3
Culture Techniques
for Bacteriology

2. Culture Techniques Master basic techniques Aseptic technique
Safe work practices
Correct selection and use of growth media

3. Aseptic Technique Set of safe work practices to
Prevent infection from specimens
Prevent infection from cultures
Prevent cross-contamination of cultures
Prevent environmental contamination of cultures
Prevent work surface contamination

4. Aseptic Technique Physical barriers Protective clothing
Safe use of equipment
Sterilizing loops
Avoiding creation of aerosols
Class II safety cabinets
HEPA filter

5. Aseptic Technique

6. Aseptic Technique Disinfection Sterilization Disinfectants – surfaces
Antiseptics – skin
Factors affecting efficacy
See Tables 7-14 and 7-15
Sterilization

7. Growth Media Can be liquid or solid (agar) Purposes
Recover organism from specimen
Support growth of organism
Isolation of organism
See Tables 7-16, 7-17

8. Primary Medium Medium inoculated first Choice affects culture success
Blood agar is common choice
Enriched medium can be required
Chocolate agar

9. Selective Medium Inhibits some organisms and allows others to grow
Eosin Methylene Blue (EMB)
MacConkey’s agar (MAC)

10. Indicator Medium Shows metabolic/chemical reaction
Some media are both selective
and indicator
EMB and MAC
Hektoen enteric (HE)

11. Culture Techniques Safety Precautions Standard Precautions PPE
Aseptic technique
Hand hygiene
Surface disinfection
Autoclave materials before disposal

12. Culture Techniques Quality assessment Internal program
Media and reagent checks
Control organisms
Equipment monitoring
External program
Proficiency testing

13. Culture Techniques Specimen collection Transport media
Technique important
Correct supplies
Transport media
Follow procedure manual
Select appropriate medium

14. Culture Techniques Inoculating the agar plate Bacterial smear
Streak for isolated colonies
Bacterial smear

15. Culture Techniques
Streaking the agar plate

16. Culture Techniques Inoculating the agar slant
Indicator/selective medium

17. Culture Techniques Incubate inoculated media 35° to 37° C
Agar plates upside down
Oxygen/carbon dioxide requirements
Aerobic cultures
Anaerobic cultures
Cultures requiring increased CO2

18. Culture Techniques Observe culture after 24 hours Isolated colonies
Colony characteristics
Presence (or absence) of hemolysis
This project was funded at $3,000,000 (100% of its total cost) from a grant awarded under the Trade Adjustment Assistance Community College and Career Training Grants, as implemented by the U.S. Department of Labor’s Employment and Training Administration. Rogue Community College is an equal opportunity employer/program. Auxiliary aids and services, alternate form and language services are available to individuals with disabilities and limited English proficiency free of cost upon request.
This work is licensed under a Creative Commons Attribution 4.0 International License.