Diversity and antifungal activity of the endophytic fungi associated with the native medicinal cactus Opuntia humifusa (Cactaceae) from the United States

Publication date: Available online 21 March 2015 Source:Microbiological Research Author(s): Alice F. Silva-Hughes , David E. Wedge , Charles L. Cantrell , Camila R. Carvalho , Zhiqiang Pan , Rita M. Moraes , Victor L. Madoxx , Luiz H. Rosa The endophytic fungal community associated with the native cactus Opuntia humifusa in the United States was investigated and its potential for providing antifungal compounds. A hundred-eight endophytic fungal isolates were obtained and identified by molecular methods into 17 different taxa of the genera Alternaria, Aureobasidium, Biscogniauxia, Cladosporium, Cryptococcus, Curvularia, Diaporthe, Epicoccum, Paraconiothyrium, Pestalotiopsis and Phoma. The most frequent species associated with O. humifusa were Alternaria sp. 3, Aureobasidium pullulans and Diaporthe sp. The fungal community of O. humifusa had a high richness and diversity; additionally, the species richness obtained indicates that the sample effort was enough to recover the diversity pattern obtained. Six extracts of endophytes showed antifungal properties and 1H NMR analyses of the extracts of Alternaria sp. 5 Ohu 8B2, Alternaria sp. 3 Ohu 30A, Cladosporium funiculosum Ohu 17C1 and Paraconiothyrium sp. Ohu 17A indicated the presence of functional groups associated with unsaturated fatty-acid olefinic protons and fatty acid methylene and methyl protons. GC-FID analysis of these extracts confirmed the presence of a mixture of different fatty acids. The 1H NMR analyses...
Source: Microbiological Research - Category: Infectious Diseases Source Type: research