1. Dalia Kamal Eldien Mohammed
Culture media
Dalia Kamal Eldien Mohammed
practical NO (2)

2. Culture media
Whatever a particular mould needs, it must always be supplied with some form of organic carbon for energy, a source of nitrogen for protein and vitamin synthesis, and several minerals.
The substance on which a mould is grown in the laboratory is called a medium 
Culture media can be solid or liquid, depending on the sort of information one wishes to obtain.
For the purposes of identification, solid culture media are usually more useful, as they allow the mould to sporulate more easily.

3. Culture media
The selection of media depends on the organism if it is fastidious or non fastidious
The non fastidious fungi cultured on simple media e.g Sabouraud’s dextrose Agar or mycosel agar
Addition of chloramphenicol or mixture of penicillin and streptomycin to inhibit the bacterial growth
Addition of cyclohexamide(actide) inhibit the saprophytic fungi
Fastidious fungi need enriched media e.g brain heart infusion

4. Common media used in mycology lab
Sabouraud’s dextrose Agar
Sabouraud Dextrose Broth
Yeast Extract Peptone Dextrose (YEPD)
Malt Extract Agar
Cornmeal Agar : is used for the cultivation of fungi and the demonstration of chlamydospore production.
Potato Dextrose Agar (PDA)
Brain heart infusion (fluid& slope)

5. Preparation of media
The culture media are commercially available i.e ready made
The steps of preparation:-
Weight the dehydrated powder according to formula given by manufacture company
Most culture media are prepared by dissolving the necessary nutrients in water, to obtain a balanced solution supplying everything the mould needs for growth.
Preparation of solid media involves dissolving a solidifying agent in the solution by heat, that will harden to a gel upon cooling.

6. Pouring this step be before sterilization if we use unsterile bottle or tube
Sterilization according to the manufacture company , but generally sterilize by autoclave
Preservation Usually we use slope media in bottle or tube with screw to avoid the drying and contamination because of long incubation needed

7. Steps of preparation

8. Example Sabouraud’s Agar :
is used in the cultivation of pathogenic and commensal fungi and yeasts. It consists of a mixture of dextrose and peptone at a 2:1 ratio.

9. Example to formula Difco™ Sabouraud Brain Heart Infusion Agar Base
Approximate Formula* Per Liter
Brain Heart Digest g
Proteose Peptone g
Enzymatic Digest of Casein g
Dextrose g
Sodium Chloride g
Disodium Phosphate g
Agar g
*Adjusted and/or supplemented as required to meet performance criteria.

10. Dehydrated media

11. Dehydrated Product of SDA
1. Suspend 59 g of the powder in 1 L of purified water. Mix thoroughly.
2. Heat with frequent agitation and boil for 1 minute to completely dissolve the powder.
3. Autoclave at 121°C for 15 minutes. Cool to 50-55°C.
4. Aseptically add 1 mL chloramphenicol solution (100 mg/mL)
5. Test samples of the finished product for performance using stable, typical control cultures.