Dichloran-rose bengal medium for enumeration and isolation of molds from foods.
Overgrowth by spreading molds such as Rhizopus and Mucor species is a problem with fungal enumeration media used for foods. Thirty-one antifungal compounds were surveyed for their ability to selectively inhibit such fungi while allowing growth of mycotoxigenic molds and other species of significance in food spoilage. Dichloran (2,6 dichloro-4-nitroaniline) restricted growth of Rhizopus stolonifer while allowing satisfactory growth of the other test molds. Three Rhizopus and Mucor species were encountered that were not inhibited by dichloran; these were controlled by the addition of rose bengal. The optimal medium, designated DRBC, contained 2 micrograms of dichloran and 25 micrograms of rose bengal per ml. DRBC, in pure culture tests and with food samples, restricted the colony size of spreading molds and recovered a wider range of species in higher numbers than other enumeration media.
D000814:Aniline Compounds / Q000494:pharmacology*; D000935:Antifungal Agents / Q000494:pharmacology*; D001230:Aspergillus / Q000302:isolation & purification; D003470:Culture Media; D005516:Food Microbiology; D005658:Fungi / Q000302:isolation & purification*; D009089:Mucor / Q000187:drug effects; D010407:Penicillium / Q000302:isolation & purification; D012233:Rhizopus / Q000187:drug effects; D012395:Rose Bengal / Q000494:pharmacology; D013045:Species Specificity
D000814:Aniline Compounds; D000935:Antifungal Agents; D003470:Culture Media; D012395:Rose Bengal