SODIUM TAUROCHOLATE MEDIUM FOR THE IDENTIFICATION OF CANDIDA ALBICANS

Abstract

Most strains of Candida albicans can be identified on various agar media by their production of the characteristic chlamydospores (Skinner and Fletcher, Bacteriol. Rev. 24:397, 1960). Recently, Aschner (Bull. Research Council Israel 7E:1 57, 1958) described the preparation of another medium, sodium taurocholate agar, which he used for the identification of C. albicans. According to Aschner, C. albicans, "as a frequent inhabitant of the intestine, is well adapted to the presence of bile salts in its environment, and the taurocholate medium in this respect imitates the conditions prevailing in the natural habitat of the yeast." On this medium he was able to detect the first chlamydospores after 2 to 3 days of incubation at 37 C. These chlamydospores were usually situated in the middle streak near the edge of the cover slip, and their formation proceeded gradually from there to other parts of the covered area. He also found that outside the coverslip the formation of chlamydospores was more irregular and occurred later than in the covered part.Repeated attempts in this laboratory to obtain comparable results using known stock cultures of C. albicans, as well as unidentified "yeasts" isolated from specimens of sputum, urine, stool, etc., met with little success. When cultures in this medium were incubated at 37 C, only a few definitely recognizable chlamydospores appeared under the cover slip. When such chlamydospores were found (and this did not happen for 3 to 7 days even with all the known cultures of C.

Chlamydospore formation in Candida albicans and Candida dubliniensis– an enigmatic developmental programme

“…Raubitschek and also Bakerspigel reported rapid formation of chlamydospores on Ashner's taurocholate agar 25,26 and Pavlatou and Marselou [27] recommended a potato-carrot agar for C. albicans chlamydosporulation. Specific chlamydospore induction in C. albicans was also observed in media containing N-acetyl-Dglucosamine, 28 milk, 29 oxgall 30 and TOC (Tween-80, oxgall, caffeic acid).…”

“…A polysaccharide medium of known composition favouring chlamydospore formation was inaugurated by Nickerson and Mankowski [23] and a soil‐extract agar by Bakerspigel [24]. Raubitschek and also Bakerspigel reported rapid formation of chlamydospores on Ashner's taurocholate agar 25,26 and Pavlatou and Marselou [27] recommended a potato–carrot agar for C. albicans chlamydosporulation. Specific chlamydospore induction in C. albicans was also observed in media containing N ‐acetyl‐ d ‐glucosamine, 28 milk, 29 oxgall 30 and TOC (Tween‐80, oxgall, caffeic acid) 31 …”