Question

A gram stain of a peritoneal fluid showed large gram positive bacilli. There was 3+ growth on anaerobic media only, with colonies producing a double zone of hemolysis. To assist with the classic identification of the organism, the microbiologist could:
a. determine if the organism ferments glucose
b. perform the oxidase test
c. set up egg yolk agar plate
d, test for bile tolerance

Answer 1

To assist with the classic identification of the organism, the microbiologist could set up egg yolk agar plate.

Option: C

Explanation:

• Egg Yolk Agar is based on the classic Egg Yolk Agar formulation generated by McClung and Toabe for the separation and classification of species on the basis of development of lecithinase, lipase and proteolytic response.
• Highly known for presumptive Clostridium, Fusobacterium and Prevotella diagnosis.
• This can also be used for the suspected detection of Clostridium perfringens in the Nagler Test.
• In this casein enzyme hydrolysate and papaic soya meal digestive together with carbonaceous and nitrogenous compounds include the essential nutrients.  
• Here yeast extract provides components which are B-complex.  Sodium chloride keeps the osmotic balance intact.  
• L-cystine is an amino acid that functions as a reducing agent too. Vitamin K1 and hemin aid in anaerobic species development.