Different culture media containing methyldopa for melanin production by Cryptococcus species

Rev Soc Bras Med Trop. 2011 Oct;44(5):591-4. doi: 10.1590/s0037-86822011000500012.

Abstract

Introduction: Melanin production by species of Cryptococcus is widely used to characterize C. neoformans complex in mycology laboratories. This study aims to test the efficacy of methyldopa from pharmaceutical tablet as a substrate for melanin production, to compare the production of melanin using different agar base added with methyldopa, and to compare the melanin produced in those media with that produced in Niger seed agar and sunflower seed agar by C. neoformans, C. laurentii, and C. albidus. Two isolates of each species, C. neoformans, C. laurentii, and C. albidus, and one of Candida albicans were used to experimentally detect conditions for melanin production.

Methods: The following media were tested: Mueller-Hinton agar (MHA), brain and heart infusion agar (BHIA), blood agar base (BAB), and minimal medium agar (MMA), all added with methyldopa, and the media Niger seed agar (NSA) and sunflower seed agar (SSA).

Results: All isolates grew in most of the culture media after 24h. Strains planted on media BAB and BHIA showed growth only after 48h. All isolates produced melanin in MMA, MHA, SSA, and NSA media.

Conclusions: Methyldopa in the form pharmaceutical tablet can be used as a substrate for melanin production by Cryptococcus species; minimal medium plus methyldopa was more efficient than the BAB, MHA, and BHIA in the melanin production; and NSA and SSA, followed by MMA added with methyldopa, were more efficient than other media studied for melanin production by all strains studied.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agar
  • Cryptococcus / classification
  • Cryptococcus / growth & development
  • Cryptococcus / metabolism*
  • Cryptococcus gattii / growth & development
  • Cryptococcus gattii / metabolism
  • Cryptococcus neoformans / growth & development
  • Cryptococcus neoformans / metabolism
  • Culture Media / chemistry
  • Culture Media / pharmacology*
  • Melanins / biosynthesis*
  • Methyldopa / pharmacology*
  • Species Specificity

Substances

  • Culture Media
  • Melanins
  • Methyldopa
  • Agar