YM Agar and Broth, is a selective growth medium with low pH useful for cultivating yeasts, molds, or other acid-tolerant or acidophilic organisms, while deterring growth of most bacteria and other acid intolerant organisms.
[1] It is malt extract medium modified by the addition of yeast extract and peptone.
[2] The 'YM' of the name stands either for 'Yeast and Mold', or 'Yeast extract-Malt extract' depending on the source.
Variations include YMG agar/broth, which contains yeast, malt, and glucose.
[3]