Abstract: Systems for preparing cell culture dish media are provided which are well adapted for preparing cell culture media, supplements, additives and/or other ingredients in an efficient and versatile manner to form sterilized cell culture dish media having a variety of ingredients well adapted with respect to uniformity and nutritional content to culture microorganisms in a particularly effective manner. The systems include an array of filtration and steam sterilization devices to sterilize various types of media for selective combination of one or more of the types of media in a mixing chamber to form cell culture dishes (e.g., agar plates). Methods of preparing cell culture dish media and cell culture dishes are also provided.

Abstract: A preparation of antibiotic hygromycin B with low cell toxicity and high purity, and methods of preparing such a preparation, are provided. More specifically, an isolated antibiotic hygromycin B with a purity of greater than 98% and impurities C, D and E individually less than 0.5% and impurity F less than 2%, as measured by HPLC, is described. Uses of this high purity antibiotic hygromycin B include, for example, for in vitro cell selection.

Abstract: Growth medium filtration devices are provided which are particularly well adapted to sterilize gelatinous substance based growth mediums including agar, agarose and other polysaccharide derived growth mediums for use in agar plates and the like for culturing microorganisms. The devices may include one or more filtration units and at least one heat source for filtering the growth medium in a heated filtration process. Methods of filtering a growth medium, such as an agar growth medium, and methods of preparing a growth medium having low gelling point and lower molecular weight characteristics are also provided.