Ensaio para detectar bergapteno na casca e no caule de Brosimum gaudichaudii Trec através da produção de melanina em actinomicetos / A new assay for detection of furocoumarins in Brosimum gaudichaudii Trec by melanin production in actinomycetes

Plant extracts containing furocoumarins compounds were identified by using melanin producer strains of Nocardiopis sp (DAUFPE-361) and non producer strains of Streptomyces sp (DAUFPE-87). Ethanol, methanol and acetone extracted compounds from conduru (Brosimum gaudichaudii) bark and stem were evaporated and added to tubes containing ISP7 medium (tyrosine agar). This medium was inoculated with spore suspension (10(6)-10(7) CFU) prepared from the different actinomycetes strains. The ethanol fraction (pH 9.0) from both bark and stem induced pigmentation in actinomycetes melanin non producer strains and increased the pigmentation in producer strains indicating presence of furocoumarins in the correspondent plant extracts.