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1.
Braz J Microbiol ; 53(3): 1425-1437, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35446011

RESUMO

This study explores the biotechnological potential of lignocellulolytic fungi collected in an oak forest. Fungal collections were obtained from natural reserves located in Boyacá-Colombia, ranging from 2700 to 3000 m.a.s.l. Twenty-three strains were isolated on malt agar, molecular characterization was performed, and ligninolytic and cellulolytic enzymatic activities were screened. Several white-rot fungi of biotechnological importance were identified as follows: Trametes sp., Trametes versicolor, Trametes villosa, Pycnoporus sanguineus, Bjerkandera adjusta, Lentinula boryana, Panus conchatus, Antrodia neotropica, Brunneoporus malicola, Laetiporus gilbertsonii, Stereum sp., Ganoderma sp., and Dichomitus sp. The strains T. versicolor 0554 and 0583, T. villosa 0562, and B. adusta 0556 showed the highest response in the qualitative enzymatic assays. These strains were used to determine their ability to decolorate the dyes aniline blue and Congo red, and it was found that T. villosa 0562 reached a level of decolorization close to 90% after 48 h of submerged culture. The fungal strains obtained here could offer alternatives to develop a process to accomplish sustainable development objectives.


Assuntos
Trametes , Madeira , Colômbia , Corantes , Florestas , Madeira/microbiologia
2.
Fungal Biol ; 122(9): 891-899, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30115323

RESUMO

Cordyceps tenuipes is an entomopathogenic fungus that infects mostly pupae of several lepidopteran families. In Colombia the species has been reported in non-disturbed tropical rain forests and more recently in butterfly gardens. The aim of this study was to assess the genetic diversity in populations of C. tenuipes present in natural (forests) and artificial (e.g. butterfly gardens) environments in the department of Quindío, Colombia, using three molecular nuclear markers ITS, TEF-1α and RPB1. All the samples evaluated corresponded morphologically and phylogenetically to C. tenuipes. The butterfly garden of Quindio Botanical Garden (QBG) showed the highest genetic diversity among all sampling localities and was very similar to that of its adjacent forest. The Amaranta Butterfly Garden (ABG), located north of QBG, showed lower genetic diversity as well as little genetic differentiation with QBG, consistent with the hypothesis of a pathogen transfer from QBG to ABG. Higher FST values were observed for TEF-1α and ITS, revealing genetic differentiation between all demes and the southern forest population. Our research constitutes the first study of the intraspecific diversity of C. tenuipes in Colombia and can serve as the first step in identifying diversity reservoirs and management of epizootic episodes caused by this fungal species.


Assuntos
Borboletas/microbiologia , Cordyceps/genética , Cordyceps/patogenicidade , Florestas , Jardins , Animais , Colômbia , Variação Genética , Filogenia
3.
IMA Fungus ; 8(2): 335-353, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29242779

RESUMO

The ending of dual nomenclatural systems for pleomorphic fungi in 2011 requires the reconciliation of competing names, ideally linked through culture based or molecular methods. The phylogenetic systematics of Hypocreales and its many genera have received extensive study in the last two decades, however resolution of competing names in Cordycipitaceae has not yet been addressed. Here we present a molecular phylogenetic investigation of Cordycipitaceae that enables identification of competing names in this family, and provides the basis upon which these names can be maintained or suppressed. The taxonomy presented here seeks to harmonize competing names by principles of priority, recognition of monophyletic groups, and the practical usage of affected taxa. In total, we propose maintaining nine generic names, Akanthomyces, Ascopolyporus, Beauveria, Cordyceps, Engyodontium, Gibellula, Hyperdermium, Parengyodontium, and Simplicillium and the rejection of eight generic names, Evlachovaea, Granulomanus, Isaria, Lecanicillium, Microhilum, Phytocordyceps, Synsterigmatocystis, and Torrubiella. Two new generic names, Hevansia and Blackwellomyces, and a new species, Beauveria blattidicola, are described. New combinations are also proposed in the genera Akanthomyces, Beauveria, Blackwellomyces, and Hevansia.

4.
PLoS One ; 12(6): e0179428, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28636672

RESUMO

Cordyceps sensu lato is a genus of arthropod-pathogenic fungi, which have been used traditionally as medicinal in Asia. Within the genus, Ophiocordyceps sinensis is the most coveted and expensive species in China. Nevertheless, harvesting wild specimens has become a challenge given that natural populations of the fungus are decreasing and because large-scale culture of it has not yet been achieved. The worldwide demand for products derived from cultivable fungal species with medicinal properties has increased recently. In this study, we propose a new species, Cordyceps nidus, which parasitizes underground nests of trapdoor spiders. This species is phylogenetically related to Cordyceps militaris, Cordyceps pruinosa, and a sibling species of Cordyceps caloceroides. It is found in tropical rainforests from Bolivia, Brazil, Colombia and Ecuador. We also investigated the medicinal potential of this fungus based on its biochemical properties when grown on four different culture media. The metabolic profile particularly that of nucleosides, in polar and non-polar extracts was determined by UPLC, and then correlated to their antimicrobial activity and total phenolic content. The metabolome showed a high and significant dependency on the substrate used for fungal growth. The mass intensities of nucleosides and derivative compounds were higher in natural culture media in comparison to artificial culture media. Among these compounds, cordycepin was the predominant, showing the potential use of this species as an alternative to O. sinensis. Furthermore, methanol fractions showed antimicrobial activity against gram-positive bacteria, and less than 3.00 mg of gallic acid equivalents per g of dried extract were obtained when assessing its total phenolic content by modified Folin-Ciocalteu method. The presence of polyphenols opens the possibility of further exploring the antioxidant capacity and the conditions that may enhance this characteristic. The metabolic composition and biochemical activity indicate potential use of C. nidus in pharmaceutical applications.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Cordyceps/metabolismo , Bactérias Gram-Positivas/efeitos dos fármacos , Metabolômica , Nucleosídeos/metabolismo , Ásia , Cordyceps/crescimento & desenvolvimento
5.
Fungal Biol ; 119(10): 901-916, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26399185

RESUMO

The neotropical biogeographic zone is a 'hot spot' of global biodiversity, especially for insects. Fungal pathogens of insects appear to track this diversity. However, the integration of this unique component of fungal diversity into molecular phylogenetic analyses remains sparse. The entomopathogenic fungal genus Ophiocordyceps is species rich in this region with the first descriptions dating to the early nineteenth century. In this study, material from various ecosystems throughout Colombia and Ecuador was examined. Molecular phylogenetic analyses of five nuclear loci including SSU, LSU, TEF, RPB1, and RPB2 were conducted alongside a morphological evaluation. Thirty-five specimens were examined representing fifteen different species of Ophiocordyceps, and five new species, Ophiocordyceps blattarioides, Ophiocordyceps tiputini, Ophiocordyceps araracuarensis, Ophiocordyceps fulgoromorphila, and Ophiocordyceps evansii, were described. An accurate identification of the host allowed us to conclude that host identity and host habitat are positively correlated with phylogenetic species of Ophiocordyceps and are probably strong drivers for speciation of neotropical entomopathogenic fungi.


Assuntos
Variação Genética , Hypocreales/classificação , Hypocreales/isolamento & purificação , Insetos/microbiologia , Animais , Análise por Conglomerados , Colômbia , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Equador , Proteínas Fúngicas/genética , Hypocreales/citologia , Hypocreales/genética , Dados de Sequência Molecular , Filogeografia , RNA Ribossômico/genética , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , Clima Tropical
6.
IMA Fungus ; 5(1): 121-34, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25083412

RESUMO

Ophiocordycipitaceae is a diverse family comprising ecologically, economically, medicinally, and culturally important fungi. The family was recognized due to the polyphyly of the genus Cordyceps and the broad diversity of the mostly arthropod-pathogenic lineages of Hypocreales. The other two cordyceps-like families, Cordycipitaceae and Clavicipitaceae, will be revised taxonomically elsewhere. Historically, many species were placed in Cordyceps, but other genera have been described in this family as well, including several based on anamorphic features. Currently there are 24 generic names in use across both asexual and sexual life stages for species of Ophiocordycipitaceae. To reflect changes in Art. 59 in the International Code of Nomenclature for algae, fungi, and plants (ICN), we propose to protect and to suppress names within Ophiocordycipitaceae, and to present taxonomic revisions in the genus Tolypocladium, based on rigorous and extensively sampled molecular phylogenetic analyses. When approaching this task, we considered the principles of priority, monophyly, minimizing taxonomic revisions, and the practical utility of these fungi within the wider biological research community.

7.
Mycologia ; 106(2): 260-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24782494

RESUMO

In the Amazon the only described species of Cordyceps sensu stricto (Hypocreales, Cordycipitaceae) that parasitize insects of Orthopterida (orders Orthoptera and Phasmida) are Cordyceps locustiphila and C. uleana. However, the type specimens for both taxa have been lost and the concepts of these species are uncertain. To achieve a more comprehensive understanding of the systematics of these species, collections of Cordyceps from the Amazon regions of Colombia, Ecuador and Guyana were subjected to morphological, ecological and molecular phylogenetic studies. Phylogenetic analyses were conducted on partial sequences of SSU, LSU, TEF, RPB1 and RPB2 nuclear loci. Two new species are proposed including C. diapheromeriphila, a parasite of Phasmida, and C. acridophila, a parasite of the superfamily Acridomorpha (Orthoptera), which is broadly distributed across the Amazon. For C. locustiphila a lectotypification and an epitypification are made. Cordyceps locustiphila is host specific with Colpolopha (Acridomorpha: Romaleidae), and its distribution coincides with that of its host. The phylogenetic placement of these three species was resolved with strong support in the Beauveria clade of Cordyceps s. str. (Cordycipitaceae). This relationship and the morphological similarity of their yellow stromata with known teleomorphs of the clade, suggest that the holomorphs of these species may include Beauveria or Beauveria-like anamorphs. The varying host specificity of the beauverioid Cordyceps species suggest the potential importance of identifying the natural host taxon before future consideration of strains for use in biological control of pest locusts.


Assuntos
Cordyceps/isolamento & purificação , Gafanhotos/microbiologia , Insetos/microbiologia , Animais , Cordyceps/classificação , Cordyceps/genética , Cordyceps/fisiologia , DNA Fúngico/genética , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
8.
Rev. biol. trop ; 49(3/4): 945-955, Sep.-Dec. 2001.
Artigo em Espanhol | LILACS | ID: lil-333092

RESUMO

Entomopathogenic fungi of the genus Cordyceps were sampled in the foothills of the Colombian Amazon region (450-600 msnm altitude. January and May, 1998, i.e. dry and wet seasons, respectively). Healthy and Cordyceps-parasitized ants from a nearly pristine, a naturally disturbed and a human-disturbed forests were collected on 100 quadrants (1 m2) per forest. Litter, shrubs and trunks were explored as substrates, and samples were gathered in vertical strata from 50 cm to 2 m high. Azteca was the predominant ant genus in near pristine forest whereas Camponotus, Pheidole and Crematogaster were dominant in disturbed forests. In the naturally disturbed forest we found 759 individuals of Cordyceps unilateralis and 69 of C. lloydii var. binata parasitizing Camponotus spp. (Formicidae: Formicinae), whereas C. kniphofioides var. ponerinarum and C. australis were found only in six cases infecting the ants Paraponera clavata and Pachycondila crassinoda (Formicidae: Ponerinae). In the human disturbed forest it were found 34 individuals of C. unilateralis on Camponotus. In the near pristine forest we did not find parasitized ants. The Camponotus spp. ants parasitized by C. unilateralis and C. lloydii var. binata were found predominantly in the substratum foliage up to 1 m. It was concluded that the incidence of Cordyceps-ant interactions is not influenced by the conservation status of the forest. Instead, relative humidity and presence/absence of host ants appear to be key factors. Also, the microspatial distribution of the interactions seems to follow a definite pattern. This work observations support the hypothesis on coevolution of dispersion mechanisms in Cordyceps and ant pheromonal codes.


Assuntos
Animais , Formigas , Árvores/classificação , Ascomicetos , Formigas , Ascomicetos , Colômbia , Características de Residência , Ecossistema , Densidade Demográfica , Estações do Ano
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