Microbiological assay of shampoo

• Take the loopful culture of staphylococcus aureus aseptically and transfer to sterilized and cooled 100 ml SCDM (broth).

• Mix well. Incubate the broth at 37oC for 24 hrs. Soya bean casein (milk protein) digests medium, soya bean casein digest agar and nutrient agar may be used as medium.

• Sterilized SCD agar (100 ml) is cooled to 40°C and mixed with 5 ml of 24 hrs old pre inoculated culture. This is immediately poured in plates (340 ml each) and allows to set.  

 

• The wells are dig on agar plates with sterilized well digger aseptically. Take 100µml of each sample, add to well aseptically

• Incubate the plates at 37ºC for 24 hrs to 48 hrs. Observe the effectiveness of sample on culture growing on the agar plate and we can see the effectiveness of sample in the form of zone of inhibition around each well containing different sample