Yeast, Peptone, Dextrose (YPD) Medium The medium was prepared using milli-Q grade water. It was prepared in screw bottles and autoclaved at 121 degreesC, and 15psi for 15 minutes. YDP is also known as rich medium. This medium is undefined since it contains other denatured yeast cells in the form of yeast extract. Yeast cells are cultured/grown up to a fixed optical density (O.D) on this medium since yeast cells have a high growth rate on rich when compared to minimal medium. Contents: yeast extract (20g/L) peptone (bacteriological, 40g/L) Dextrose (2% 40g/L) Geneticin (200ug/L)