[Evaluation of melanin production by Cryptococcus species in four different culture media].
The capacity of Cryptococcus spp to produce melanin in media containing phenol compounds is widely used for identifying these species in the laboratory. The aim of the present study was to compare the production of this pigment by Cryptococcus spp. in four culture media. Sixteen strains of Cryptococcus neoformans, 17 of Cryptococcus albidus, 13 of Cryptococcus laurentii and two of Cryptococcus uniguttulatus were tested in the following media: potato-carrot agar, Niger seed agar, sunflower seed agar and L-dopa agar. The melanin production was evaluated on the basis of colony pigmentation. Its production after five days of incubation was demonstrated by 93.8% of the strains of Cryptococcus neoformans in the media of potato-carrot agar, sunflower seed agar and L-dopa agar. From the isolates of Cryptococcus albidus, 29.4% produced the pigment in potato-carrot agar and L-dopa agar, 11.8% in Niger seed agar and 36% in sunflower seed agar. From Cryptococcus laurentii, 53.8% produced the pigment in potato-carrot agar and sunflower seed agar, 61.5% in L-dopa agar and 84.6% in Niger seed agar. Only one strain of Cryptococcus uniguttulatus presented slight production of the pigment, in potato-carrot agar.
Pedroso
Reginaldo dos Santos
RS
Laboratório de Micologia Clínica, Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Via do Café s/n, Bairro Monte Alegre, Ribeirão Preto, SP.
da Costa
Karen Regina Carim
KR
Ferreira
Joseane Cristina
JC
Candido
Regina Celia
RC
D000362:Agar; D003454:Cryptococcus / Q000145:classification / Q000201:enzymology*; D003455:Cryptococcus neoformans / Q000201:enzymology*; D003470:Culture Media; D008543:Melanins / Q000096:biosynthesis*
D003470:Culture Media; D008543:Melanins; D000362:Agar