September 16, 2021: Pharmaceutical Interview Questions and Answers
#QualityControlOfCultureMedia #TestForQualityControlForCultureMedia #GrowthPromotionTestForMicrobiologyCultureMedia #EnvironmentIsolatesForGPT
1. Why quality control of culture media is important?
Quality control of culture media is essential to provide assurance that the results generated from microbiology laboratories are accurate.
2. Which types of quality control test are done for culture media?
The quality control of culture media can be divided into two parts, physical verification and microbial characteristics.
3. What types of physical characteristics can be used as a quality control test for microbiology culture media?
Following physical characteristics can be used for preliminary inspection of microbiology culture media for acceptance.
● Description: Sterilized culture medium should be compared against non-sterilized medium for any color differences. Media should not have any extraneous matter such as particle
● Clarity: Clarity of the media can be checked for any abnormality such as crystallization
● Media volume: Volume of media, specifically for solid media should be optimum to prevent drying upon exposure/ incubation
● Gel-strength: It should be firm and usable
● pH: Within acceptable range
● Checks for damage: Media, media container should not be damaged
● Any other abnormality: Such as detachment of media from Petri plate side wall
4. What types of microbiological characteristics can be used as a quality control test for microbiology culture media?
Following microbiological characteristics can be used for preliminary inspection of microbiology culture media for acceptance.
● Media sterility to detect microbial contamination during the manufacturing process by incubating media at 30–35 °C for 3 days.
No growth should be observed.
● Challenging of culture media with growth promotion test.
5. Why Growth Promotion test (GPT) of microbiology culture media is carried out?
For growth promotion test is carried out to demonstrate the suitability of the media for its intended use.
6. Which organisms are used to perform Growth Promotion test of microbiology culture media?
Pharmacopeia recommends specific microorganisms that are traceable to a reputable culture collection, such as the American Type Culture Collection (ATCC). The standard set of typed cultures detailed in the European Pharmacopeia and United States Pharmacopeia are given in the following table.
|Microorganism Culture collection||ATCC No.|
|Staphylococcus aureus subsp. aureus||6538|
|Bacillus subtilis subsp. spizizenii||6633|
|Salmonella enterica subsp. enterica serovar typhimurium||13311|
In addition to the standard cultures, environmental isolates are generally used during growth promotion testing.
7. Why environment isolates are used during Growth Promotion test (GPT) of microbiology culture media?
To demonstrate that the manufactured culture media lot grows microorganisms that are general found in product manufacturing facility environment and media will facilitate and detect the growth while media used for product testing or environmental monitoring.