Second year Lab Medicine (Females)
Sponsored Links
This presentation is the property of its rightful owner.
1 / 45

By: Hibah A. W. Abusulaiman PowerPoint PPT Presentation

  • Uploaded on
  • Presentation posted in: General

Second year Lab Medicine (Females) 1433- 1434 A.H. / 2012- 2013 Microbiology Practical (Course I). By: Hibah A. W. Abusulaiman. Once upon a time…. Please don’t sleep. Fashionable friends. Abrar’s …. Sara started the preparation early. She got a luxurious manicure and padicure plus….

Download Presentation

By: Hibah A. W. Abusulaiman

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript

Second year Lab Medicine (Females)

1433- 1434 A.H. / 2012- 2013

Microbiology Practical (Course I)

  • By:

    Hibah A. W. Abusulaiman

Once upon a time…

Please don’t sleep

Fashionable friends


Sara started the preparation early

She got a luxurious manicure and padicure plus…

An elegant evening gown

Lubna started the preparation 2 days before the wedding

She got an elegant evening gown, but…

A poor manicure and padicure

Both attended the wedding in…

After 45 days, Lubna was suffering from…

Diagnosed as Hepatitis Patient

After discussion with the Doctor, she knew it’s because of the poor hygienic manicure and pedicure

Good hygiene

Poor hygiene

Destruction of Microorganisms

So, do you think we are in a war with…?!

Simply because they are the agents of…

Contamination, infection and decay

Early civilization

In the 1800s

Aseptic techniques invented to prevent contamination of surgical wounds

Many organizations classified infection control systems and substances into:

  • Physical methods.

  • Chemical methods.

Referred broadly as Germicides

Germicidal systems fall into three categories:

  • Decontamination.

  • Disinfection.

  • Sterilization.

1. Decontamination:

  • Reduction of pathogenic microorganisms to be safe to handle without protective attire.

  • The Lowest level of control.

  • Includes physical cleaning with soap and detergents and removing of most organic and inorganic materials.

  • It is the critical step toward disinfection and steilisation.

2. Disinfection:

  • Disinfectants are liquid chemical agents that kill targeted pathogens but not spores . It can also be solid or gaseous.

  • It is the next level of control.

3. Sterilization

  • The complete elimination of viable organisms including spores.

  • The highest level of control

Factors influencing disinfection

  • Number of microorganisms.

  • Species and type of microorganism.

  • Temperature.

Physical Antimicrobial Agents

  • Physical environmental agents can destroy large concentrations of microorganisms in lab cultures or a clinical specimen.

Physical Antimicrobial Agents


UV Light

To inactivate microorganisms on surfaces


  • Filtration is used to remove bacteria, fungi and their endospores from air or solutions.

Osmotic Pressure

  • Extremely hypertonic conditions can cause plasmolysis.


AutoclaveMoist heat- Steam sterilization121OC for 15 min

Dry heat160OC for 2 hours OR 170OC for an hour

Chemical Antimicrobial Agents

  • In considering their application to patient care, two general classes:

    • Those destroying pathogenic microorganisms in the environment (disinfectants) or on skin (antiseptics).

    • Those administered to patients for treatment of infectious diseases (antimicrobial agents, often called antibiotics).


Evaluating a disinfectant

  • Direct spray method.

  • Testing the quality of disinfectant from different brands.

Testing Disinfectant from Different Brands

0.5 mL

5 mLDettol

5 mL Clorox

5 mL DAC

5 mLGento

5 mL Bacterial Suspension in Nutrient Broth (Control)

Testing Disinfectant from Different Brands

Water Bath

Bacteria in Clorox

Bacteria in Dettol

Bacteria in DAC

Bacteria in Gento

Bacterial Suspension in Nutrient Broth (Control)

Testing Disinfectant from Different Brands

2 Loopfulls

48 hrs


in the 37O C

Water Bath

After 5min

in Water Bath

After 10 min in

Water Bath

After 20 min in

Water Bath

Bacterial Suspension in Nutrient Broth (Control)

Observe the bacterial growth


  • Some infection control terms.

  • Factors influencing disinfectants.

  • Physical destruction of microorganisms.

  • Chemical destruction of microorganisms.

  • Methods of evaluating disinfectants.

Thank you for listeningAny questions?!

Thank you for paying attention 

Any questions?!

  • Login