What Is Nutrient Agar?
Nutrient agar is a general purpose/basal medium that support the growth of a wide range of non-fastidious organisms (microbes that grow and thrive without specific nutritional or environmental conditions). It is commonly used for cultivation and maintenance of microbial cultures for scientific study or identification. It typically contains (mass/volume):
- 0.5% Peptone – this provides organic nitrogen
- 0.3% beef extract/yeast extract – the water-soluble content of these contribute vitamins, carbohydrates, nitrogen, and salts
- 1.5% agar – this gives the mixture solidity
- 0.5% Sodium Chloride – this gives the mixture proportions similar to those found in the cytoplasm of most organisms
- distilled water – water serves as a transport medium for the agar’s various substances
- pH adjusted to neutral (6.8) at 25 °C (77 °F).
These ingredients are combined and boiled for approximately one minute to ensure they are mixed and then sterilized by autoclaving, typically at 121 °C (250 °F) for 15 minutes. Then they are cooled to around 50 °C (122 °F) and poured into Petri dishes which are covered immediately. Once the dishes hold solidified agar, they are stored upside down and are often refrigerated until used. Inoculation takes place on warm dishes rather than cool ones: if refrigerated for storage, the dishes must be rewarmed to room temperature prior to inoculation.
What You Need To Know About Nutrient Agar
- Nutrient agar refers to a general purpose medium that supports the growth of a wide range of non-fastidious organisms.
- Nutrient agar contains peptone, yeast extract, beef extract, NaCl, agar and water.
- Nutrient Agar contains 2% agar for solidification.
- Nutrient agar is a solid medium.
- Nutrient agar is poured into Petri plates, culture bottles, test tubes etc.
- Nutrient agar is used for colony formation of microorganisms.
What Is Nutrient Broth?
Nutrient broth is a general purpose medium used for cultivating a broad variety of fastidious and non-fastidious microorganism with non-exacting nutritional requirements. It contains peptone, yeast extract, beef extract, Nacl and water. Peptone and yeast extract provide nitrogenous compounds, carbon, vitamins and some trace ingredients necessary for the growth of bacteria.
What You Need To Know About Nutrient Broth
- Nutrient broth refers to a general purpose, liquid medium that allows the growth of fastidious organisms.
- Nutrient broth contains peptone, yeast extract, beef extract, Nacl and water.
- Nutrient broth does not contain agar.
- Nutrient broth is a liquid medium.
- Nutrient broth is poured into culture bottles, test tubes etc.
- Nutrient broth is used to maintain stocks of microorganisms.
Difference Between Nutrient Agar And Nutrient Broth In Tabular Form
BASIS OF COMPARISON | NUTRIENT AGAR | NUTRIENT BROTH |
Description | Nutrient agar refers to a general purpose medium that supports the growth of a wide range of non-fastidious organisms. | Nutrient broth refers to a general purpose, liquid medium that allows the growth of fastidious organisms. |
Ingredients | Nutrient agar contains peptone, yeast extract, beef extract, NaCl, agar and water. | Nutrient broth contains peptone, yeast extract, beef extract, Nacl and water. |
Agar | Nutrient Agar contains 2% agar for solidification. | Nutrient broth does not contain agar. |
Medium | Nutrient agar is a solid medium. | Nutrient broth is a liquid medium. |
Glassware | Nutrient agar is poured into Petri plates, culture bottles, test tubes etc. | Nutrient broth is poured into culture bottles, test tubes etc. |
Use | Nutrient agar is used for colony formation of microorganisms. | Nutrient broth is used to maintain stocks of microorganisms. |
Similarities Between Nutrient Agar And Nutrient Broth
- Nutrient agar and nutrient broth are two types of growth media.
- Both nutrient agar and nutrient broth are general purpose media.
- Both nutrient agar and nutrient broth are inexpensive.
- Both nutrient agar and nutrient broth consist of beef extract and peptones.
- The pH of both nutrient agar and nutrient broth are 7.3.
- Both nutrient agar and nutrient broth are used to cultivate microorganisms.