Pharmaceutical Grade (USP) agar is a highly purified extract of select Gelidium marine algae, forming part of the cell wall, that gives excellent growth characteristics used in a wide variety of microbiological applications. Agar is a phycocolloid, a complex mixture of several sugar compounds that retains a gelatinous structure at room temperature after boiling. Bacteriological agar is purified by successive washings to remove or extensively reduce chemical contaminants, color and salts. After autoclaving, agar is a light amber and free of particulates, solidifying into a clear, firm gel and suitable for all molecular biology applications. Bacterial and phage growth (M13 and Lambda) is superior to standard microbiology grade agars.