Sterilization and disinfection
True statement is:(AIPG 07)
|A||Solid media are enrichment media|
|B||Nutrient broth is a basal medium|
|C||Agar adds to the nutrients of the medium|
|D||Chocolate agar is a selective medium|
a. Liquid media which contain a selective agent that suppresses the growth of unwanted bacteria are called enrichment media.
b. Basal media are simple media in which only non-fastidious bacteria grow. Eg. Peptone water, nutrient broth and nutrient agar.
c. Agar used for solidifying media does not contain any growth promoting or growth inhibiting substances.
d. Chocolate agar is an enriched medium.
IMPORTANT GROWTH FACTORS
T.B., M. microti
Aryl Sulphate, Amide
Factors V. & X
Factor V (All Haemophilus species which begin with the prefix para like H. Parainfluenza do not require X factor for growth)
· (in Ducreyi D for Dus) (in Para P for Paanch)
ü Factor V = NAD, X = Hemin
ü Iron required for growth. of - Shigella, Neisseria, C. Diphtheriae
ü Vit B6 required for growth of - Group D streptococci
OXIDASE AND CATALASE ARE IMPORTANT TESTS USED FOR IDENTIFICATION OF BACTERIA
Important bacteria which are oxidase negative-Staphylococcus, Streptococcus and Enterobacteriaceae
Important bacteria which are Catalase negative-Streptococcus, Sh.dysenteriae Type I, anaerobes