High-transparency PDA (potato dextrose agar) culture medium preparing method

Abstract

The invention belongs to the field of PDA (potato dextrose agar) culture medium preparing methods and discloses a high-transparency PDA culture medium preparing method.The method includes steps: A, potato dicing; B, stewing, to be more specific, stewing over strong fire and then slow fire to make potato dices thoroughly cooked but not mushy; C, filtering; D, material adding, to be more specific, adding 20g of glucose, 0.8-1.4g of monopotassium phosphate and 1.2-1.7g of magnesium sulfate into filtrate obtained at the step C, well mixing, and adding water to a constant volume of 1000mL; E, pH value regulation, to be more specific, using a hydrochloric acid and a sodium hydroxide solution for regulating the pH value to 6.5-7 to obtain a liquid culture medium, distributing 19-23g of high-purity agar powder into a plurality of mixing containers, then distributing the liquid culture medium into the mixing containers, and well mixing; F, transferring to flat-plate petri dishes; G, dehumidifying, namely putting the petri dishes over flame of an alcohol lamp to remove moistures; H, sealing and sterile testing.The high-transparency PDA culture medium preparing method has the advantages that raw materials can be proportionally mixed precisely and quickly, and system errors and operation errors are avoided; moistures in the petri dishes can be well controlled to avoid breeding of contaminating microorganisms.

Description

technical field [0001] The invention relates to the field of preparation methods of PDA culture medium, in particular to a preparation method of high-transparency PDA culture medium. Background technique [0002] In the field of fungal microorganism culture, people often use potato dextrose agar medium. The existing common practice is: first wash and peel, then weigh 200g potatoes and cut them into small pieces, add water to boil, filter with eight layers of gauze, heat, and then According to the actual experiment, add 1-10g of agar, continue to heat and mix well, after the agar is dissolved, add glucose, stir evenly, after cooling down slightly, make up water to 1000ml, divide into test tubes or Erlenmeyer flasks, stopper, bandage, After sterilizing for about 20 minutes, take out the test tube and put it on an inclined plane or shake it well, and store it after cooling. This preparation method has the following defects: the one is to cause operational error, first add agar...

AI Technical Summary

Problems solved by technology

This preparation method has the following defects: the one is to cause operational error, first add agar powder and then add glucose, the agar powder will become paste after contacting water, easy to form agglomerates, mix unevenly, and easily stick to the pan, causing other added ingredients to be absorbed by the agar agglomerate It sticks and it is difficult to mix evenly. After mixing, it needs to be changed to a container such as a triangular flask. The culture solution added with agar has a high viscosity and sticks to the steel pot, funnel, glass rod and spoon, which is time-consuming and affects the accuracy of the ratio. , will cause operational errors; the second is to cause system errors

After the prepared potato liquid is fixed to volume, add auxiliary materials and agar powder and continue heating and boiling to completely melt the agar, so that a lot of water will evaporate during the heating process, resulting in changes in the concentration of each component in PDA, which cannot reach the standard amount , resulting in systematic errors; third, the prepared PDA medium has a low specific transparency, which is not conducive to subsequent inoculation operations