Sabouraoud Dextrose media contains all essential nutrients required for the growth of fungi.
Fungi are eukaryotic organism and found to be from unicellular to multicellular. The example of unicellular fungi is yeast and mushroom is multicellular. They can be pathogenic or non pathogenic. They are also found to be associated with plants symbiotically and they are called as mycorrhizae. In its life cycle two morphological distinct phases vegetative and reproductive are observed.
They are heterotrophic and found to follow three modes for obtaining the nutrition namely saprotrophic, parasitic and mutualistic. In saprotrophic mode, the fungi obtain nutrition from dead material. In parasitic, they feeds on living host and mutualistic mode, they may mutually associate with other life form and exchange the nutrition. To grow fungi in laboratory, the commonly used media is Sabouraud Dextrose Broth media.
Sabouraoud Dextrose Agar/Broth is used for isolation, cultivation and maintenance of fungi. The media contains peptone and it provides nitrogen, amino acid and peptides and dextrose provides energy for the growth. The media contains vitamins that are required for fungal growth and multiplication.
In fungi cultivation media, antibiotics are added in order to inhibit the growth of bacteria and avoid contamination
Requirements for Sabouraoud Dextrose media:
|Dextrose (Glucose)||40 gm|
|Distilled Water||1000 ml|
|pH||5.6 (+/- 0.2)|
- Antibiotic (Tetracycline/Ampicillin)
- Inoculating loop
- Conical flask
Procedure for Sabouraoud Dextrose media:
- Weigh all the ingredient and add in 800 ml distilled water
- Heat the media to dissolve all the ingredients
- Make up the volume up to 1 liter.
- Check the pH and adjust to 5.6 by using acid or alkali
- Autoclave the media at 121 °C for 20 min.
- After autoclaving, once the media is cooled upto 45°C, pour it into tubes or petri plates.
The SDA media is prepared and now it is ready for inoculation of fungi.
Identification of Fungi –
The fungi can be preliminiary identified by studying the shape, color, size and structure of the fungal colony. They can be further studied microscopically. They can also be identified by physiological and biochemical tests.
SDA media contains all essential nutrient for fungal growth and hence it is one the best media for its cultivation.
Limitations of Sabouraoud Dextrose Agar
- The media is unable to support growth of few fungal strains.
- The media is found to be incompetent for canidation of filamentous fungi.
- The added antibiotics may also inhibit few fungal strain growth.