Isolation of Isolation of bacteria in purebacteria in purebacteria in pure bacteria in pure 

cultureculture

Isolation:Isolation: To separate a single species ofTo separate a single species ofIsolation: Isolation: To separate a single species of To separate a single species of bacteria from a mixed population.bacteria from a mixed population.

Pure culturePure culture consists of only a single typeconsists of only a single typePure culture Pure culture consists of only a single type consists of only a single type of organism.of organism.

AiAiAim:Aim:To To identifyidentify the the bacterial pathogensbacterial pathogensTo To identifyidentify the the bacterial pathogensbacterial pathogens

Mixed culturesMixed culturesMixed culturesMixed cultures

**Usage of selective andUsage of selective and Stabbing method:Stabbing method:**Usage of selective and Usage of selective and differential mediadifferential media

Stabbing method:Stabbing method:

**To differentiate between To differentiate between 

Streak plate techniqueStreak plate technique::motile and nonmotile and non‐‐motile bacteria.motile bacteria.

**Isolation of bacteria in pure Isolation of bacteria in pure culture from clinical specimen.culture from clinical specimen. SpreadingSpreading‐‐plate method:plate method:

PouringPouring‐‐plate method:plate method:**Quantification of bacteria in     Quantification of bacteria in     liquid cultures, urine sample.liquid cultures, urine sample.

**To differentiate between To differentiate between aerobic and anaerobic bacteria.aerobic and anaerobic bacteria.

**Swabbing from clinical Swabbing from clinical samples.samples.

Streak PlateStreak PlateStreak PlateStreak Plate((Quadrant Streak,Quadrant Streak, loop dilutionloop dilution))

Pure culturePure culture

Coloneal morphologyColoneal morphologyColoneal morphologyColoneal morphology

Spread plate techniqueSpread plate technique

Stabbing methodStabbing methodgg

+ve -ve-ve

Classification of Bacteria accordingClassification of Bacteria accordingClassification of Bacteria according Classification of Bacteria according to Oto O22 requirementrequirement22

11. Aerobic:. Aerobic: Pseudomonas.Pseudomonas.

22. Anaerobic:. Anaerobic: Clostridia.Clostridia.33 F l i biF l i bi S iS i E liE li33. Facultative anaerobic:. Facultative anaerobic: Streptococci, Streptococci, E. coliE. coli..44.. MicroaerophilicMicroaerophilic:: Helicobacter pyloriHelicobacter pylori44. . MicroaerophilicMicroaerophilic:: Helicobacter pyloriHelicobacter pylori..55. . CapnophilicCapnophilic:: NeisseriaNeisseria, Enterococci., Enterococci.66. . AerotolerantAerotolerant

Anaerobic conditions can be obtained by: Anaerobic conditions can be obtained by: 11. . Exclusion of OExclusion of O22 by heating or vacuum. by heating or vacuum. 22 Ab ti f OAb ti f O b h i lb h i l22. . Absorption of OAbsorption of O22 by chemical means. by chemical means. 33 Reduction of OReduction of O22 by candle or Gas Packby candle or Gas Pack33. . Reduction of OReduction of O22 by candle or Gas Pack by candle or Gas Pack Jar.Jar.44. . Ridding of ORidding of O22 from the mediafrom the media by by Thiogl collateThiogl collate medi mmedi mThioglycollateThioglycollate medium medium