How does nutrient agar work




















Microbial growth media contains nutrients and an energy source to fuel the microbes as they grow, and agar to keep the media in a semi-solid, gel-like state. On solid media, a single microbe will grow and divide to produce a "colony," a spot of identical descendants.

Different types of microbes produce colonies with different characteristics-shape, color, texture-which help microbiologists determine if a culture is pure, or identify the types of microbes in a mixed sample.

A number of biological supply companies sell pre-made plates, but making your own is much less expensive. With a little practice, you will find that it is very easy to make your own plates, and you will have the added flexibility of being able to customize recipes to suit your needs. Choose a recipe from the Media Recipes page or use one of your own. Decide how many plates you will need. Our recipes will make 1 L mL of media, enough to fill approximately forty mm plates, but they can be scaled up or down as needed.

Plan on using about 25 mL per mm plate. Use a glass container ideally an Erlenmeyer flask that will hold at least twice the volume of your media. Make sure the agar dissolves completely. The media may look cloudy, or you may see small, translucent lens-like objects floating in it. Continue boiling until the media is completely clear; this may take longer than 15 minutes. Incompletely dissolved agar will leave your media squishy or fragile.

Log in Register. Log in. Create an Account First Name:. Last Name:. The contents of nutrient broth are the same as those for nutrient agar except that the agar is omitted. Its preparation and storage are the same as described for nutrient agar. The amount of medium mentioned in this procedure is adequate to make about 20 bottles. Please manage the amount accordingly, based on your requirements. News Ticker. Nutrient Agar. Contents 1 Composition of Nutrient Agar 1. That is faster than a passenger jet at takeoff!

The method for the preparation of basic microbiology media is given below. In situations where preparation is uneconomic in time, prepared, sterilized media liquid and solid are available from the major school science equipment suppliers. All cotton wool plugs should be made of non-absorbent cotton wool. Plastic or metal caps may also be used. Suspend 28 g of nutrient agar powder in 1 litre of distilled water. Bring to the boil to dissolve completely.

Dispense as required and sterilize. Add 13 g of nutrient broth powder to 1 litre of distilled water. Mix well. Suspend 18g agar powder in 1 litre of distilled water. Add 15g malt extract per litre. Suspend 10 g agar in 1 litre of distilled water. Heat to dissolve. Add 0. Supplied ready for use. Heat to melt and dispense aseptically. Add 10 g of peptone, 5 g of NaCl, 3 g of yeast extract to 1 litre of distilled water.

Sterilize separately. Dispense aseptically. Allow to cool and then mix with the nutrient agar solution. Dispense and sterilize. Curious about microbiology?



0コメント

  • 1000 / 1000