Nutrient Agar is a general purpose, nutrient medium used for the cultivation of microbes supporting growth of a wide range of non-fastidious organisms. Nutrient agar is popular because it can grow a variety of types of bacteria and fungi, and contains many nutrients needed for the bacterial growth.
Composition of Nutrient Agar
- 0.5% Peptone
It is an enzymatic digest of animal protein. Peptone is the principal source of organic nitrogen for the growing bacteria.
- 0.3% beef extract/yeast extract
It is the water-soluble substances which aid in bacterial growth, such as vitamins, carbohydrates, organic nitrogen compounds and salts.
- .5% agar
It is the solidifying agent.
- 0.5% NaCl
The presence of sodium chloride in nutrient agar maintains a salt concentration in the medium that is similar to the cytoplasm of the microorganisms.
- Distilled water
Water is essential for the growth of and reproduction of micro-organisms and also provides the medium through which various nutrients can be transported.
- pH is adjusted to neutral (7.4) at 25 °C.
Preparation of Nutrient Agar
1. Suspend 28 g of nutrient agar powder in 1 litre of distilled water.
2. Heat this mixture while stirring to fully dissolve all components.
3. Autoclave the dissolved mixture at 121 degrees Celsius for 15 minutes.
4. Once the nutrient agar has been autoclaved, allow it to cool but not solidify.
5. Pour nutrient agar into each plate and leave plates on the sterile surface until the agar has solidified.
6. Replace the lid of each Petri dish and store the plates in a refrigerator.
Uses of Nutrients Agar
1. It is frequently used for isolation and purification of cultures.
2. It can also be used as a means for producing the bacterial lawns needed for antibiotic sensitivity tests. In actuality, antibiotic sensitivity testing is typically performed on media specially formulated for that purpose.
- List of culture media used in microbiology with their uses
- Simmons Citrate Agar- Composition, Principle, Uses, Preparation and Result Interpretation
- Blood Agar- Composition, Preparation, Uses and Pictures
- Salmonella Shigella (SS) Agar- Composition, Principle, Uses, Preparation and Result Interpretation
72 thoughts on “Nutrient Agar: Composition, Preparation and Uses”
How much powder and water would I need to make 10 nutrient agar plates
you’ll need aprox. 20ml media per plate. That amounts to 200mL
To be on the safer side, always prepare a little more than the required amount. So you’ll need 250mL media. So calculate accordingly.
Hi, I’m currently doing a project on microbial fuel cells. Basically, I need to mix 30g of agar, water and salt; the problem is that I don’t know how many grams of salt are needed.
Salt isn’t nutritious I’ve grown a lot on agar and would say it’s not needed. Put some light malt extract in their. 1g agar 1g lme and 50 ml h2o. Scale ingredients.
What are the used of the components of nutrient agar
Nutrient agar media is used for microbiological growth which is not fastidious. It is useful because it remains solid even at relatively high temperature. Bacteria in nutrient agar grow in surface and are closely surface as in small colonies
Suspending 28 g of nutrient agar powder in 1 litre of distilled water.
what will be the amount of media required for preparation of 6 plates (25ml media per plate)
As one needs to add anti-biotics to the agar to prevent the growth of bacteria (so the fungi can grow), what do we need to do the opposite? (Grow bacteria & stop fungi)
Bacteria grow within 1-2 days (under incubation) but fungi will take more time and prefers to grow under room temperature (in India)… so you may take your plates out of incubation after 2 days and refrigerate them.
Alternatively, you may use Sabouraud’s Agar instead of Nutrient Agar.
150ml of the 1litre of agar culture will be required
Isn’t it 167ml per plate
per plate approx 15 to 20 ml of media.
That was for 1 plate
For 6, it will be 4.2g
Suspend 4.2 gram of nutrient agar in 150ml of distilled water for the preparation of 6 plates of 25ml each
Which is a good media for the antibiotic sensitivity testing, Mueller Hinton Agar (MHA) or Nutrient Agar?
MHA… It can be used for any bacteria and contains starch which will regulate diffusion of other nutrients
how to grow Bascilius sp. in liquid and solid from(protease,amylase)
Can nutrient agar be used for a total bacterial count?
What quantity of nutrient agar will be required to be suspended in 500ml of distilled water.
It may depend on the manufacturer of the brand of nutrient agar you will use. But for all the ones i have worked with, it was specified that one one should use 28g/l which would mean 14g/500ml.
For 1000 ml it is 28 grams hence 500 ml requires 14 grams of nutrient agar with an extra addition of 0.5% agar to better solidification
14gms from cross multiplication
Can Enterococcus faecalis grow on nutrient agar?
We need 14g of nutrient agar powder to add to 500 mls of distilled water.
yes it can grow depending on the agar been use to grow the bacteria
Hello… I wonder that I can ask a question about my problems. I did subculture Bacteria Lignolytic, Selulotic and Cytophaga on Nutrient Broth. But the result the subculture turning into red. I suspected that subculture contain E.coli. I’m not sure about that.
That % mean for 1000ml or 1l you need that particular amount of any substance,like peptone for Nam that is 5gm for 1000ml . Now if you have to prepare low amount of medium then you have to reduce the %. Here you mentioned for 1l media you have to add 1% malt extract for 500lm media it’ll be .5% of malt extract.. That’s how it works
Could you please tell me what exactly we use nutrient agar for
Minly it is used for bacterial culture growth.
Show the composition mode preparation and types of organism cultured media
Shall we use nutrient agar medium prepared without sodium chloride?
I have heard from several growers to prepare this with brewers yeast, bees pollen, and shaved coconut. You blend the pollen and coconut. Then you add the brewers yeast. This all gets mixed into the agar mixture and it must be Prepared before you begin the agar. add 5% gypsum and 5% activated charcoal by your measurement. So in grams. Also this is a recipe for growing mushrooms. This would be a ph balanced substrate and it would be loaded with a blend of complex polysaccharides, omega-3, the immunological benefits of the bees pollen. Once you pour the dishes let it cool as this instruction says. You need to Pasteurize though, do not sterilize. The reason is because you kill all good and all bad microbes. When you pasteurize you kill the bad and leave the good. So it is recommended to pressure cook at 0 psi and I apologize I only know °F but you bring it to 145 and then turn the heat down or off. The heat will continue to climb up to between 165 -175 °F. After this cools down to roughly 70°F you would then inoculate the agar dishes and close the lids for the final time with polypore tape. This from my understanding is a master mix for agar. Dubbed WhittingtonsMastersMix or WMM for short… feel free to copy the recipe. Anyone can make this at home. Hope to see the research on medicinal mushrooms continuing to expand or health, or longevity, our nerves, please get a hold of some research about Chaga, Reishe, Lions Mane, or Gametes Trametes better know as the turkey tail. Also look into the Studies being down in Oakland on the Psilocybe mushrooms as the new law that decriminalized mushrooms and other plants. The time for research is now! And Remember!! TRYING IS POWERLESS, IT IS ONE FOOT IN AND ONE FOOT OUT. IT IS INDECISION. IT IS YOUR SELF GETTING IN YOUR WAY. IT IS INDECISION. DECIDE TO DO. THE POWER TO TAKE BACK CONTROL OF YOUR LIFE IS TAKING OWNERSHIP OF YOUR ACTIONS AND RESPONSIBILITIES. THERE IS NO TRY, THERE IS ONLY DO. I wish you all the best in life, in love, in health in all its’ forms. Peace and blessings. May your consciousness be ever hungry for growth!
If possible could you add me to the group? I am an aspiring Microbiologist and hope to get more insight or even help in the field and my studies. Thank you, 07756316834.
Good morning, pls am interested in joining the whatsapp group for microbiologist. Here’s my no.pls add it. 07030151444. Thanks
Two types ke bacteria gram positive and gram negative
Agar are come from huge agar plant know as kelps .are cooked with dilute acid and filtered the acidic liquid is neutralized and cooled so that agal gel is obtained
what are the characteristics of a high quality agar for bacterial growth????
For 1 L media we need 0.4% yeast extract, 1% malt extract, and 0.4% glucose.
My question is: What does % mean?
To prepare 1 L media we need yeast extract 0.4%. malt extract 1%, and glucose 0.4%.
My question is: what does % mean?
0.4 % of 1000 ml media is 0.48*1000/100= 4 gm/ Liter of the solute.
1% of 1000 ml media is 1*1000/100= 10 gm/Lt.
Are you kidding Ritesh Sharma
It’ll be 0.48*1000/100=4.8gm
What about adding he chemical formula?
What about nutrient broth ? Composition ?
I dont know about that but you can add a broad spectrum antibiotic to avoid griwth of bacteria in your plates
Whats the basic defferences between all culture media
And which culture media would use for which????
Sir I have used nutrient agar for fungus culture…. Before i use PDA for culture it was gud…. But i found lots of bacterial contamination in my Nutrient agar culture…. Does the composition of beef extract hampers the groeth of fungus and favours bacteria instead.
how microbes get water content while they are cultured on the nutrient agar plates
What is Basal media????
peptone water, Nutrient broth, and nutrient agar. non enriched general purpose media.
What is Basal media
It media that supports the growth of bacteria but do not need nutrients
can this basal media use for bacterial survivalence.
how to subculture B.pulimnus
Hello I have a question. If a leg wound is cultured and it is put on a nutrient agar, Selective agar and Differential Agar what are expected to show?
What is the principle or action of nutrient media?
Hi ! I streaked out from sweet potato steep water and I had both red colonies and white colonies that turned nutrient agar kind of green. Please what kind of organisms are these . They areboth staining gram positive
yes both are gram positive
Nutrient agar favored 4 Non fastidious bacteria
Blood agar used to detect bacteria that produce enzymes to break apart the Red blood cells
Mac conkey agar favored 4 gram – bacteria
sabouraud agar favoured 4 fungi
lowenstein jensen agar favored 4 mycobacterium tuberculosis
salmonella shigella agar favored in the isolation of salmonella&shigella
the compositon and funtions were helpful. but i dont really get the beef extract could you please explain more. you did a nice job. my name is Anie, 19yr old microbiology student, i’m currently in my 3rd year in Uni
among the types of medias we have can somebody help me and tell me the kind of micro organism to which each media favour the growth
eg nutrient agar favour the growth of …..
which dye is used for nutrient agar
what is the color of nutrient agar?
go close to d practical,and the Petri dish you get to see the colour after inoculation and culture
Could u tell me what are the microbial techniques? Just list put techniques name so that i could learn it from basics.
Could u tell me what are the microbial techniques? Just list out the techniques name so that i could learn it from basics.
I wonder about questions such as Pseudomonas aeruginosa colonies on nutrient agar?