Agar, a gelatin like substance extracted from red algae, is commonly used to culture microorganisms. Various nutrients like potato dextrose added to agar to enhance the growth of bacteria in either shallow plates or test tubes. Agar slants are created by bringing agar to the boiling point and pouring it into a test tube. Before the agar cools and solidifies, the test tube is set on its side. Once the agar is cooled, the test tube can be stored upright, and the agar inside has a slanted appearance. When agar media is placed in test tubes it is in liquid form. The test tubes are placed on an angle to cool and congeal, creating a slanted surface, or an agar slant. Keep the solidified slants in inverted position for about 1 min to 2 hrs. So the media gets cooled and vapors come down and is absorbed by cotton. Keep it inverted even after streaking the culture in slants.Try it it really works.After solidifying slants invert them upside inside laminar flow for one hr, or keep them inverted position in sterilize 4 degree refrigeration unit.
Agar, a gelatin like substance extracted from red algae, is commonly used to culture microorganisms. Various nutrients are added to agar to enhance the growth of bacteria in either shallow plates or test tubes. When agar media is placed in test tubes it is in liquid form. The test tubes are placed on an angle to cool and congeal, creating a slanted surface, or an agar slant. Keep the solidified slants in inverted position for about 1 min to 2 hrs. So the media gets cooled and vapors come down and is absorbed by cotton. Keep it inverted even after streaking the culture in slants.Try it it really works.After solidifying slants invert them upside inside laminar flow for one hr, or keep them inverted position in sterilize 4 degree refrigeration unit.
Before adding the dehydrated agar powder, mix it with a small amount of cold distilled water to prevent lumping. Use caution when adding agar to the hot liquid since it can foam and overflow the pot. Add small amounts of agar at a time and stir to evenly distribute the agar. Turn off the heat when the mixture begins to steam, before it boils.
Before adding the dehydrated agar powder, mix it with a small amount of cold distilled water to prevent lumping. Use caution when adding agar to the hot liquid since it can foam and overflow the pot. Add small amounts of agar at a time and stir to evenly distribute the agar. Turn off the heat when the mixture begins to steam, before it boils.
When the agar is still hot, carefully tilt the rack holding the test tubes on a solid surface or a thick book, making sure the medium inside the tubes is at a slanted position relative to the test tubes. Allow the medium to cool and solidify at this angle, which increases the surface area of the agar. Tighten the caps of the test tubes after the agar has cooled. The slants are ready for use once the agar has solidified. They can be stored at room temperature or in the refrigerator for future use.
Inoculate the slant by transferring cells with an inoculating loop from a single-colony microorganism on a plate to the slant’s surface. Move the loop across the surface of the slant and recap the tubes. Incubate the slant until there is evidence of growth, then put the tube in a refrigerator.
The medium is prepared differently for slants than petri dishes. Sterilization is done with the agar in the tubes; petri dishes are pre-sterilized before sterilized agar is poured into them. Measure the amount of water needed and put it in an Erlenmeyer flask. Heat it on a stove until it is almost boiling. Add other ingredients if needed and stir the mixture slowly and constantly until they dissolve. These ingredients may include beef extract, peptone, and pH buffers, depending on the type of microorganism being cultured.