????? ???????? ????? ???????? Staining of Bacteria

1
????? ???????? ????? ???????? Staining of
Bacteria

• ?????? ??????? ??? ???? ??? ?????
• ???? ??????? / ????? ??????

2

• Bacterial Staining Bacterial identification is
  aided by their staining reactions, as stain
  combine chemically with the bacterial protoplasm.
  Most microbiological dyes may be divided into two
  groups
• 1- Basic stains
• They carry positive charges like a methylene
  blue , crystal violet , methyl violet , gentian
  violet , safranin ( counter stain ) , basic
  fuchsine stain .
• 2- Acidic stains
• They carry negative charges like eosin, nigrosin
  , acid fuchsine .

3

• In general, the stains are divided three groups
• Simple stains methylene blue , safranin ,
  crystal violet .
• Differential stains
• Gram stain (crystal violet or methylene blue
  safranin ) .
• Acid fast stain.
• Special stains
• Capsular stain ( India ink nigrosin ) .
• Spore stain ( malachite green ) .
• Albert stain.

4
Gram staining procedure
5
Gram stain scheme
6
Gram positive and negative bacteria
7
Gram positive and negative bacteria
8

• Thank you for listening to me