Corynebacterium diphtheriae can be grown within 6-8 hour on: (A) Potassiu, tellurite media with iron, (B) McConkey's agar, (C) Dorset egg medium, (D) Loeffler's serum slope
Answer is D. The usual media employed for the cultivation of diphtheria bacilli are Loeffler's serum slope and Tellurite blood agar. Loeffler's serum slope: Diphtheria bacilli grow on Loeffler's serum slope very rapidly and colonies can be seen in 6-8 hours, long before other bacteria grow. Colonies are first small, circular white opaque discs but enlarge on continued incubation and may acquire a distinctly yellow tint. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 242