Cultivation And Identification Of Bacteria Flashcards
First screening step in identification
Organisms microscopic morphology and staining characteristics
Wet mount preparation
Easy,Rapid
1-Collect sample from container
2-Add sample to slide
3-Place cover slip on sample
Steps of preparing a bacterial smear
1- smear of bacteria —> drop of a broth, colony from agar medium
2- smear is dried in air
3- slide is heat-fixed
Simple stain procedure
Useage of only 1 stain—> methylene blue
Most common and staining procedure
Gram staining
Steps of gram staining
1-Fixation
2- crystal violet
3-Iodine treatment
4-Decolorization
5- Counter stain fuchsin
Decolorization done with which substance for how long
Alcohol
10 seconds
Crystal violet and Iodine is used for how long
1 minute
Basic fuchsin for how long
30 seconds
By the help of gram-staining procedure we can observe
Gram properties of the bacteria
Morphology of the bacteria
When some bacterias can not be satined by gram staining bc of their cell-wall which staining can be use
Acid fast satining
Which satins used in AFS
Methylene blue
Carbon Fuchsin
Ziehl Neelsen is type of which satining
Acid Fast —> methylene blue
Nocardia Asteroides
A type of Acid fast staining
TB Auromine/Rhodamine
Acid fast stain
Lactophenol cotton blue
Used in wet mount procedure
Visualization of fungal structures
Indian ink for
Cryptococcus neoformans—> fungi
What is cultivation
Process of growing microorganisms by taking them from infection site and grow them on artificial environment
Common ingredients of media
Agar
Peptone
Yeast extract
Meat extract
Water
NaCl
2 types of media
Enriched
Selective
Types of enriched media
Sheep blood agar
Chocolate agar
Types of selective media
MacConkey
Hektoen Enteric agar
Thayer Martin
2 ways for Inoculation on Agar media
1- Striking method
2- Quantitative
Chocolate agar contains
X (hemin)
V( NAD) factors
Mac Conkey agar contains
Lactose
Bile salts
Identification of gram positives done by
Catalase
Coagulase
