Culture medium is a nutrient artificially prepared for the growth and maintenance of microorganisms, plant tissues and animal tissues, and generally contains carbohydrates, nitrogen-containing substances, inorganic salts (including trace elements), vitamins and water. According to the actual needs, some compounds that cannot be synthesized by themselves, that is, growth factors, can be added to different media. Some microorganisms, such as autotrophic microorganisms, do not need carbon sources, so the above substances are only general.
It is best to go to some reputable manufacturers to buy culture medium. Although many manufacturers now have culture media, it is still necessary to avoid buying fakes.