Definitions for nutrient agar
This page provides all possible meanings and translations of the word nutrient agar
agar, nutrient agar(noun)
any culture medium that uses agar as the gelling agent
Nutrient agar is a microbiological growth medium commonly used for the routine cultivation of non-fastidious bacteria. It is useful because it remains solid even at relatively high temperatures. Also, bacteria grown in nutrient agar grows on the surface, and is clearly visible as small colonies. In nutrient broth, the bacteria grows in the liquid, and is seen as a soupy substance, not as clearly distinguishable clumps. Nutrient agar typically contains: ⁕0.5 % Peptone ⁕0.3 % beef extract/yeast extract ⁕1.5 % agar ⁕0.5% NaCl distilled water ⁕pH adjusted to neutral at 25 °C. Nutrient broth is made identically, except omitting the agar. Composition Ingredients Gms / Litre Peptic digest of animal tissue 5.000 Sodium chloride 5.000 Beef extract 1.500 Yeast extract 1.500 Agar 15.000 Final pH 7.4±0.2 Formula adjusted, standardized to suit performance parameters Directions Suspend 28 grams in 1000 ml distilled water. Heat to boiling to dissolve the medium completely. Dispense as desired and sterilize by autoclaving at 15 lbs pressure for 15 minutes. Mix well before pouring. Principle And Interpretation Nutrient media are basic culture media used for maintaining microorganisms, cultivating fastidious organisms by enriching with serum or blood and are also used for purity checking prior to biochemical or serological testing. Nutrient Agar is ideal for demonstration and teaching purposes where a more prolonged survival of cultures at ambient temperature is often required without risk of overgrowth that can occur with more nutritious substrate. This relatively simple formula has been retained and is still widely used in the microbiological examination of variety of materials and is also recommended by standard methods. It is one of the several non-selective media useful in routine cultivation of microorganisms. It can be used for the cultivation and enumeration of bacteria which are not particularly fastidious. Addition of different biological fluids such as horse or sheep blood, serum, egg yolk etc. makes it suitable for the cultivation of related fastidious organisms. Peptic digest of animal tissue, beef extract and yeast extract provide the necessary nitrogen compounds, carbon, vitamins and also some trace ingredients necessary for the growth of bacteria. Sodium chloride maintains the osmotic equilibrium of the medium.
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"nutrient agar." Definitions.net. STANDS4 LLC, 2014. Web. 8 Mar. 2014. <http://www.definitions.net/definition/nutrient agar>.