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1.
World J Microbiol Biotechnol ; 34(11): 162, 2018 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-30368630

RESUMO

This study was conducted to report the richness of endophytic Penicillium and Talaromyces species isolated from Tillandsia catimbauensis, a bromeliad endemic in the Brazilian tropical dry forest (Caatinga), to verify their ability to produce the enzyme L-asparaginase and to partially optimise the production of biomass and L-asparaginase of the best enzyme producer. A total of 184 endophytes were isolated, of which 52 (29%) were identified through morphological and phylogenetic analysis using ß-tubulin sequences into nine putative species, four in Penicillium and five in Talaromyces. Talaromyces diversus and T. cf. cecidicola were the most frequent taxa. Among the 20 endophytic isolates selected for L-asparaginase production, 10 had the potential to produce the enzyme (0.50-2.30 U/g), especially T. cf. cecidicola URM 7826 (2.30 U/g) and Penicillium sp. 4 URM 7827 (1.28 U/g). As T. cf. cecidicola URM 7826 exhibited significant ability to produce the enzyme, it was selected for the partial optimisation of biomass and L-asparaginase production. Results of the 23 factorial experimental design showed that the highest dry biomass (0.66 g) was obtained under pH 6.0, inoculum concentration of 1 × 108 and 1% L-proline. However, the inoculum concentration was found to be statistically significant, the pH was marginally significant and the concentration of L-proline was not statistically significant. L-Asparaginase production varied between 0.58 and 1.02 U/g and did not reach the optimal point for enzyme production. This study demonstrates that T. catimbauensis is colonised by different Penicillium and Talaromyces species, which are indicated for enzyme production studies.


Assuntos
Asparaginase/biossíntese , Endófitos/enzimologia , Proteínas Fúngicas/biossíntese , Penicillium/enzimologia , Talaromyces/enzimologia , Tillandsia/microbiologia , Asparaginase/genética , Brasil , Endófitos/genética , Endófitos/isolamento & purificação , Florestas , Proteínas Fúngicas/genética , Penicillium/genética , Penicillium/isolamento & purificação , Filogenia , Talaromyces/genética , Talaromyces/isolamento & purificação
2.
IMA Fungus ; 8(1): 77-97, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28824841

RESUMO

Brazil harbours a unique ecosystem, the Caatinga, which belongs to the tropical dry forest biome. This region has an important diversity of organisms, and recently several new fungal species have been described from different hosts and substrates within it. During a survey of fungal endophyte diversity from cacti in this forest, we isolated cladosporium-like fungi that were subjected to morphological and multigene phylogenetic analyses including actA, ITS, LSU, rpb2 and tub2 gene sequences. Based on these analyses we identified two new species belonging to the genus Toxicocladosporium, described here as T. cacti and T. immaculatum spp. nov., isolated from Pilosocereus gounellei subsp. gounellei and Melocactus zehntneri, respectively. To improve the species recognition and assess species diversity in Toxicocladosporium we studied all ex-type strains of the genus, for which actA, rpb2 and tub2 barcodes were also generated. After phylogenetic reconstruction using five loci, we differentiated 13 species in the genus. Toxicocladosporium velox and T. chlamydosporum are synonymized based on their phylogenetic position and limited number of unique nucleotide differences. Six strains previously assigned to T. leucadendri, including the ex-type strain (CBS 131317) of that species, were found to belong to an undescribed genus here named as Neocladosporium gen. nov., with N. leucadendri comb. nov. as type species. Furthermore, this study proposes the actA, ITS, rpb2 and tub2 as main phylogenetic loci to recognise Toxicocladosporium species.

3.
Artigo em Inglês | MEDLINE | ID: mdl-28368305

RESUMO

Water contamination with large amounts of industrial textile coloured effluents is an environmental concern. For the treatment of textile effluents, white-rot fungi have received extensive attention due to their powerful capability to produce oxidative (e.g., ligninolytic) enzymes. In addition, other groups of fungi, such as species of Aspergillus and Trichoderma, have also been used for textile effluents treatment. The main aim of the present study was to requalify a Brazilian Trichoderma culture collection of 51 Trichoderma strains, isolated from different sources in Brazil and preserved in the oldest Latin-American Fungal Service Culture Collection, The Micoteca URM WDCM 804 (Recife, Brazil). Fungal isolates were re-identified through a polyphasic approach including macro- and micro-morphology and molecular biology, and screened for their capability to decolourise real effluents collected directly from storage tanks of a textile manufacture. Trichoderma atroviride URM 4950 presented the best performance on the dye decolourisation in real textile effluent and can be considered in a scale-up process at industrial level. Overall, the potential of Trichoderma strains in decolourising real textile dye present in textile effluent and the production of the oxidative enzymes Lac, LiP and MnP was demonstrated. Fungal strains are available in the collection e-catalogue to be further explored from the biotechnological point of view.


Assuntos
Corantes/metabolismo , Resíduos Industriais , Trichoderma/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Brasil , Corantes/química , Têxteis
4.
Braz J Microbiol ; 46(1): 49-57, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26221088

RESUMO

Bauhinia forficata is native to South America and used with relative success in the folk medicine in Brazil. The diversity, antibacterial activity, and extracellular hydrolytic enzymes of endophytic fungi associated with this plant were studied. Plant samples, which included leaves, sepals, stems, and seeds, were used. Ninety-five endophytic fungal were isolated (18 from leaves, 22 from sepals, 46 from stems, and nine from seeds), comprising 28 species. The most frequently isolated species were Acremonium curvulum (9.5%), Aspergillus ochraceus (7.37%), Gibberella fujikuroi (10.53%), Myrothecium verrucaria (10.53%) and Trichoderma piluliferum (7.37%). Diversity and species richness were higher in stem tissues, and Sorensen's index of similarity between the tissues was low. Eleven fungi showed antibacterial activity. Aspergillus ochraceus , Gibberella baccata , Penicillium commune , and P. glabrum were those with the greatest antibacterial activity against Staphylococcus aureus and/or Streptococcus pyogenes . Thirteen species showed proteolytic activity, particularly Phoma putaminum . Fourteen species were cellulase positive, particularly the Penicillium species and Myrmecridium schulzeri . All isolates tested were xylanase positive and 10 showed lipolytic activity, especially Penicillium glabrum . It is clear that the endophytic fungi from B. forficata have potential for the production of bioactive compounds and may be a source of new therapeutic agents for the effective treatment of diseases in humans, other animals, and plants. To our knowledge, this is the first study of endophytic fungi from different tissues of B. forficata and their biotechnological potential.


Assuntos
Anti-Infecciosos/metabolismo , Bauhinia/microbiologia , Biodiversidade , Endófitos/classificação , Fungos/metabolismo , Hidrolases/metabolismo , Plantas Medicinais/microbiologia , Bactérias/efeitos dos fármacos , Produtos Biológicos/metabolismo , Biotecnologia/métodos , Brasil , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , Testes de Sensibilidade Microbiana , América do Sul , Tecnologia Farmacêutica/métodos
5.
Braz. j. microbiol ; 46(1): 49-57, 05/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-748247

RESUMO

Bauhinia forficata is native to South America and used with relative success in the folk medicine in Brazil. The diversity, antibacterial activity, and extracellular hydrolytic enzymes of endophytic fungi associated with this plant were studied. Plant samples, which included leaves, sepals, stems, and seeds, were used. Ninety-five endophytic fungal were isolated (18 from leaves, 22 from sepals, 46 from stems, and nine from seeds), comprising 28 species. The most frequently isolated species were Acremonium curvulum (9.5%), Aspergillus ochraceus (7.37%), Gibberella fujikuroi (10.53%), Myrothecium verrucaria (10.53%) and Trichoderma piluliferum (7.37%). Diversity and species richness were higher in stem tissues, and Sorensen’s index of similarity between the tissues was low. Eleven fungi showed antibacterial activity. Aspergillus ochraceus, Gibberella baccata, Penicillium commune, and P. glabrum were those with the greatest antibacterial activity against Staphylococcus aureus and/or Streptococcus pyogenes. Thirteen species showed proteolytic activity, particularly Phoma putaminum. Fourteen species were cellulase positive, particularly the Penicillium species and Myrmecridium schulzeri. All isolates tested were xylanase positive and 10 showed lipolytic activity, especially Penicillium glabrum. It is clear that the endophytic fungi from B. forficata have potential for the production of bioactive compounds and may be a source of new therapeutic agents for the effective treatment of diseases in humans, other animals, and plants. To our knowledge, this is the first study of endophytic fungi from different tissues of B. forficata and their biotechnological potential.


Assuntos
Anti-Infecciosos/metabolismo , Biodiversidade , Bauhinia/microbiologia , Endófitos/classificação , Fungos/metabolismo , Hidrolases/metabolismo , Plantas Medicinais/microbiologia , Brasil , Bactérias/efeitos dos fármacos , Produtos Biológicos/metabolismo , Biotecnologia/métodos , Endófitos/isolamento & purificação , Endófitos/metabolismo , Fungos/classificação , Fungos/isolamento & purificação , Testes de Sensibilidade Microbiana , América do Sul , Tecnologia Farmacêutica/métodos
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