The Potato dextrose broth culture medium is used for the cultivation and counting of yeasts and molds, many microalgae and bacteria. Dextrose Agar potato is a product of Nikooraee company.
What is Brass Culture?
The potato dextrose agar medium is a general culture medium for yeast and mold. It can be supplemented with acid or antibiotics to prevent the growth of bacteria. The counting method is used when testing food, dairy and cosmetics. The USP cites potato dextrose agar as one of the recommended culture media for use in microbial counting experiments when testing unnecessary medicinal products. Dextrose potatoes are also used to stimulate spore formation (slide preparation), maintain cultures of specific dermatophytes, and differentiate atypical dermatophytes with pigment production. A general purpose watery medium for yeasts and molds that does not use agar, which is a solid.
Ingredients of PDB medium
Ingredients of Potato dextrose NIKOORAEE based on potato starch, potato extract and dextrose cause significant growth of fungi. Decreasing the pH of the medium to approximately 3.5 with sterile tartaric acid inhibits bacterial growth. However, it is important to avoid warming the medium after acidification as this will hydrolyze the agar and impair its ability to be strong. In general, to reduce material degradation, it is advisable to reduce the number of heat sterilization steps.
Instructions for preparation of potato dextrose broth medium
۱٫ Pour 24 grams of broth medium powder in 1 liter of distilled or purified water. If you want to use this medium by adding solid agar instead of 24 grams, you should use 39 grams per liter.
۲٫ While stirring repeatedly, heat it and simmer for 1 minute until the powder is completely dissolved. As a general guideline for the culture medium when your medium is completely dissolved when the solution boils.
۳٫ Autoclave at 121 ° C for 15 minutes.
۴- To change the reaction of potato dextrose agar medium to pH 3.5, cool the base to 45-50 ° C. Then add a decent amount of 10% sterile tartaric acid to the medium. Mix well. Do not reheat the agar-containing medium as the gelatinizing property of the agar may decrease or even disappear.
۵- Testing end-product samples for performance using stable and conventional control culture.
How to fill test tubes with potato dextrose broth
If you use test tubes or petri or any autoclavable container and similar tubing for cultivating your microorganism, it is best to add the potato dextrose into them before autoclaving, which will save a lot of time. Also, there is no possibility of contamination of the medium and container when transferring the autoclaved medium to the container.
۱- Wash and dry the test tubes first.
۲٫ Pour the warm potato dextrose NIKOORAEE medium (if it is broth , you can use it cool) to a third of the tube into the tube.
Close the pipe door using cotton or aluminum. If you are using aluminum, let the lid loose to allow heat and steam pressure into the tube when autoclaving.
۴- This stage is the autoclaving stage of the culture medium. The tubes should be positioned in an autoclave tank properly so that they do not overturn. You can put them into special pipes or even autoclavable containers like Besher the one with openings.
۵٫ After the autoclave is finished, place the tubes on a supine position, but beneath them, resting on a slope. However, this step is not required in the liquid-based Potato dextrose culture medium. But for solid media you should allow the medium to cool and solid.
For standard food, dairy and cosmetics, there are standard methods that can include disinfection before or without this stage. Note that too wet samples can increase bacterial growth.
Specimens can be placed on the potato dextrose culture medium in different ways. In the case of fragmented samples, you can place them with a forceps. For watery samples you can create small holes in the environment (by any means of sterile sharpening) and pour the liquid into these holes, but you can do this by circulating the liquid over the medium.
Place containers containing microorganisms on the potato dextrose broth medium at the desired temperature in light or dark conditions. If you are using petri, it is best to put them in a clean plastic and شnd fasten the door to close it to reduce environmental pollution.
Broth medium in tissue culture
The potato dextrose NIKOORAEE culture medium of Potito dextrose is based on a suitable medium for tissue culture of many plants. Many tissue culture and laboratory mass production companies are unaware of this environment and the possibility that it can be used as a public environment for many plants to grow. If you use Potito dextrose based media in tissue culture, you should adjust the pH of the plant before autoclaving.
Liquid media for mass production
The use of agar in the potato dextrose broth medium can pose many limitations, such as the transfer of material to seedlings and microorganisms in the liquid medium, but is restricted to the agar medium. It is also much easier to move microorganisms and seedlings into a new environment in a liquid environment and to add specific substances to them, but not in a solid environment.
Use of PDB medium for enzyme production and microorganism production
Many enzyme-producing plants and microbial products use potato dextrose-based media. The fluidity of this environment makes extraction of microbial products very easy and possible.