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1.
Mycopathologia ; 189(1): 2, 2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38217794

RESUMO

Trichophyton species cause dermatophytosis in humans, with a high, worldwide frequency of reports and important public health relevance. We evaluated 61 Trichophyton strains from different sources deposited in the University Recife Mycology (URM) culture collection of the Universidade Federal de Pernambuco, Brazil. Strains were phenotypically identified and confirmed by sequencing Internal Transcribed Spacers rDNA and partial beta-tubulin 2-exon. Additionally, we evaluated their susceptibility to terbinafine and itraconazole. Physiological analyses included urease activity and growth in casein medium. Phenotypic methods allowed the reliable identification of T. rubrum only, whereas, for other species, molecular methods were mandatory. All Trichophyton species exhibited susceptibility profiles to itraconazole (0.04-5.33 µg/mL) and terbinafine (0.17-3.33 µg/mL). Our analyses revealed a heterogeneous distribution of T. mentagrophytes, which does not support the current distribution within the species complex of T. mentagrophytes and its genotypes.


Assuntos
Arthrodermataceae , Tinha , Humanos , Trichophyton , Terbinafina/farmacologia , Antifúngicos/farmacologia , Itraconazol , Brasil , Universidades , Testes de Sensibilidade Microbiana , Arthrodermataceae/genética
2.
Artigo em Inglês | MEDLINE | ID: mdl-38194255

RESUMO

In this study, a novel genus is proposed, Scaptona, with a novel species, Scaptona ramosa, isolated from nests of stingless bees (Scaptotrigona sp.). The taxonomic novelty was determined by the phylogenetic analysis of DNA sequences from the internal transcribed spacer regions, small subunit rRNA (18S rRNA), large subunit rRNA (28S rRNA) and the RNA polymerase II second-largest subunit gene (RPB2) and paired with our morphological studies. Based on this single species, Scaptona is characterized by greyish green to dark grey colonies, densely and profusely branched conidiophores and single-celled, variously shaped hyaline conidia. Scaptona ramosa constitutes a distinct, well-supported lineage within Cephalothecaceae and can be clearly distinguished from other genera both by DNA sequence analysis and morphological traits. The holotype of S. ramosa is URM 95352. The ex-type strain has been deposited in the Micoteca URM culture collection as URM 8721T and URM 8722. The MycoBank accession number is MB 849456 for the genus and MB 849456 for the species.


Assuntos
Ácidos Graxos , Animais , Abelhas , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , RNA Ribossômico 18S
3.
Plant Dis ; 2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-37953227

RESUMO

Cucumbers have great economic and social importance. Annual worldwide production is approximately 80 million tons (FAOSTAT, 2019), 184 thousand tons of which are produced in Brazil (IBGE, 2020). Leaves with symptoms of anthracnose (necrotic brown or angular spots) were observed on cucumber plants grown in organic systems in September 2021, Pernambuco, Brazil (8°7'45''S, 35°16'167''W). About 40% of the plants fields were infected. Samples were collected and fragments were cut from the margins of the symptomatic tissue. The fragments were superficially disinfected with 70% ethanol (30 s) and 2% sodium hypochlorite (2 min), then washed three times with sterile distilled H2O and dried on sterile filter paper. The fragments were placed on potato dextrose agar (PDA) containing chloramphenicol (50 mg/L) and incubated at 28 ± 2 °C for 3 days. From the fungal isolates obtained, a representative specimen of Colletotrichum spp. was isolated, purified by subculturing from emergent hyphae tips and used for morphological characterization, phylogenetic analysis, and pathogenicity testing. The fungus isolated on PDA formed gray to grayish-black colonies with white aerial mycelia after 7 days. Ascomata were globose to subglobose, 120-200 × 100-150 µm in size (n = 10). Setae formed directly on the hyphae. Asci were 50-70 × 10-12 µm in size, 8-spored, unitunicate, thin-walled, and clavate. Ascospores were 14-22 × 4-5 µm in size (n = 30), hyaline, slightly curved to curved with obtuse to slightly rounded ends. Conidia were hyaline, smooth-walled, aseptate, straight, cylindrical, the apex and base rounded, and 12-15 × 5 µm in size, (n = 30). For molecular identification, the nuclear ribosomal internal transcribed spacers (nrITS), actin (ACT), beta-tubulin (TUB), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genes were sequenced (Damm et al. 2019). The sequences obtained were deposited in GenBank (nrITS: OP720945, ACT: OP723523, TUB: OP723525, and GAPDH: OP723524). The sequences from the nrITS region, ACT, TUB2, and GAPDH were highly similar to those from C. plurivorum: nrITS - CBS 125474 (539/539 - 100%; NR_160828); ACT - CBS 125474 (270/271 - 99%; MG600925), TUB2 - CBS 125474 (517/518 - 99%; MG600985); and GAPDH - CBS 125474 (197/197 - 100%; MG600781), respectively. Multilocus phylogenetic analysis was performed using Bayesian inference, which showed that the isolate C. plurivorum FPO04 clustered in the same clade as the ex-type of C. plurivorum (CBS 125474). In the pathogenicity test, leaves of five healthy cucumber plants, previously injured in the middle region with sterile needles, were inoculated with 50 µl of a conidial suspension (1 × 106 spores mL -1) prepared from 7-day-old of colonies of C. plurivorum. Sterile distilled water was used as negative controls. The inoculated plants were maintained in a humid greenhouse chamber for 24 hours. After 7 days, the same anthracnose symptoms seen in the field were observed on the inoculated plants. Control plants remained healthy. Colletotrichum plurivorum was reisolated from symptomatic leaves, fulfilling Koch's postulates. This species has been reported from several crops, including Abelmoschus esculentus (okra) (Damm et al. 2019) and Glycine max (soybeans) (Zaw et al. 2019). To our knowledge, this is the first report of C. plurivorum causing anthracnose on cucumber leaves in Brazil. This report lays the groundwork for future studies to determine management practices for control of this disease in C. sativus.

4.
World J Microbiol Biotechnol ; 39(11): 288, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37632594

RESUMO

L-glutaminase is a hydrolytic enzyme with wide biotechnological applications. Mostly, these enzymes are employed in the feed industry for flavor enhancement and acrylamide mitigation. Also, L-glutaminase may have antiviral and antineoplastic effects making it a good choice for pharmaceutical applications. In this study, the strain Monascus ruber URM 8542 was identified through classical and molecular taxonomy using partial sequencing of ß-tubulin and calmodulin genes. Subsequently, the optimal culture conditions were evaluated by submerged fermentation (L-glutamine 10 g.L- 1) for L-glutaminase excretion. The isolate was identified as M. ruber URM 8542 which showed significant extracellular enzyme production with a yield of 11.4 times in relation to the specific activity of intracellular L-glutaminase. Regarding the optimization experiments, several factors such as L-glutamine concentration, temperature, and pH were compared using a full factorial design (23). The concentrations greater than 1% proved to be significantly better for glutaminase production (R2 = 0.9077). Additionally, the L-glutaminase was optimally active at pH 7.0 and 30 ºC. The L-glutaminase was remarkably stable across an alkaline pH range (7.0-8.0) and had a thermal stability ranging from 30 ºC to 60 ºC for 1 h. Taken together, these findings suggest that the L-glutaminase produced by M. ruber is a promising candidate for pharmacological application, although further studies need to be performed. To the best of our knowledge, this is the first report of L-glutaminase production by Monascus ruber.


Assuntos
Sorvetes , Monascus , Glutaminase/genética , Glutamina , Monascus/genética
5.
Braz J Microbiol ; 54(3): 1665-1674, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37266822

RESUMO

Fusarium is a genus of ubiquitous fungi that comprises mycotoxigenic animal and plant pathogens. These fungi have the ability to exploit a wide range of substrates and hosts, indicating their great potential for enzyme production; however, this aspect is understudied. Therefore, the present study aimed for revaluating the identity of twenty-three Fusarium strains maintained in the University Recife Mycology (URM) culture collection, Brazil, and to evaluate their potential for proteases production and the milk-clotting activity of these proteases. According to phylogenetic analysis of translation elongation factor 1-alpha (TEF1) gene partial sequences, these strains belonged to 12 species representing four species complexes: Fusarium concolor, F. fujikuroi, F. incarnatum-equiseti, and F. oxysporum. Four of these species are putatively novel to science. Notably, novel associations of Fusarium spp. with certain hosts/substrates were documented. The proteolytic activity ranged from 1.67 U ml-1 to 22.03 U ml-1 among the evaluated fungal isolates, with specific proteolytic activity reaching 205.86 U mg-1. The values for coagulant activity and specific activity were up to 157.14 U ml-1 and 1,424.11 U mg-1, respectively. These results indicate the potential of URM Fusarium strains as a source for the production of enzymes of industrial interest. Additionally, they reinforce the importance of applying DNA-based methods for reviewing the identification of fungal strains preserved in biodiversity repositories.


Assuntos
Fusarium , Animais , Fusarium/genética , Filogenia , Brasil , Peptídeo Hidrolases/genética , Leite
6.
World J Microbiol Biotechnol ; 38(12): 247, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36289148

RESUMO

This study aimed to select endophytic fungi to produce L-asparaginase and partially optimising the production of the enzyme using cacti as substrate. Seventeen endophytes were assessed for intracellular enzymatic potential in modified Czapek Dox's medium using L-proline as an inducer. The best producer was evaluated for intracellular and extracellular enzymatic activity in modified Czapek Dox's medium using flours of Opuntia ficus-indica and Nopalea cochenillifera as substrate. The biomass and L-asparaginase production profile was analysed and the best conditions for enzyme production were verified using factorial design. Penicillium decaturense URM 7966, Diaporthe ueckerae URM 8321, and Colletotrichum annellatum URM 8538 produced 0.76 U g- 1, 0.87 U g- 1, and 0.74 U g- 1 L-asparaginase, respectively. Diaporthe ueckerae URM 8321 produced only intracellular L-asparaginase, using flours of N. cochenillifera (0.72 U g- 1) and O. ficus-indica (0.90 U g- 1) and the last was selected for the next steps. The ideal time for biomass and L-asparaginase production was 120 h. The best conditions for enzyme production (1.67 U g- 1) were initial pH 4.0, inoculum concentration 1% and cacti flour concentration 0.2%; where was observed an increase of 46.11% in compared to the initial production. Opuntia ficus-indica flour is indicated as an alternative low-cost substrate for the production of L-asparaginase by the endophytic fungus D. ueckerae URM 8321.


Assuntos
Asparaginase , Cactaceae , Fungos , Prolina
7.
Braz J Microbiol ; 53(4): 2077-2091, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36264483

RESUMO

Bat flies are obligate ectoparasitic dipterans that are highly specialised to bats and have apomorphic characteristics, such as absent or reduced wings, and specialised legs and claws, which contribute to their survival. They are often associated with fungi and harbour a fungal diversity that is still poorly understood. Fungi were found in association with the bat flies in a cave of the Caatinga dry forest in Brazil. In total, 43% of the captured bat flies were associated with fungi. Seventy-six flies were collected. DNA sequence analyses of 39 isolates showed that the isolates belonged to 13 species within nine genera, with 38 isolates belonging to Ascomycota and one isolate to Basidiomycota, and Aspergillus was the most frequently isolated genus. Most of the genera found have also been isolated from bat bodies and other substrates/hosts in caves in different regions of the world. Based on morphological and multi-locus phylogenetic analyses, two new species of Ascomycota were described: Allophoma brasiliensis sp. nov. and Pyrenochaetopsis cecavii sp. nov.


Assuntos
Ascomicetos , Ectoparasitoses , Animais , Ectoparasitoses/parasitologia , Filogenia , Florestas , Análise de Sequência de DNA
8.
Braz J Microbiol ; 53(4): 2093-2100, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36152271

RESUMO

The present study reports a new occurrence of Rhinocladiella similis isolated as an endophytic fungus in the Caatinga dry tropical forest in Brazil and describes its antifungal susceptibility. The isolate R. similis URM 7800 was obtained from leaves of the medicinal plant Myracrodruon urundeuva. Its morphological characterization was performed on potato dextrose agar medium and molecular analysis using the ITS rDNA sequence. The antifungal susceptibility profile was defined using the Clinical and Laboratory Standards Institute (CLSI) protocol M38-A2. The colony of isolate URM 7800 showed slow growth, with an olivaceous-gray color and powdery mycelium; in microculture, it showed the typical features of R. similis. In the antifungal susceptibility test, isolate URM 7800 showed high minimal inhibitory concentration (MIC) values for amphotericin B (>16 µg/mL), voriconazole (16 µg/mL), terbinafine (>0.5 µg/mL), and caspofungin (>8 µg/mL), among other antifungal drugs. Pathogenic melanized fungi are frequently isolated in environments where humans may be exposed, and these data show that it is essential to know if these isolates possess antifungal resistance.


Assuntos
Antifúngicos , Ascomicetos , Humanos , Antifúngicos/farmacologia , Brasil , Ascomicetos/genética , Florestas
10.
Biotechnol Appl Biochem ; 69(5): 2081-2090, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34617628

RESUMO

Nitrilases and nitrile hydratases/amidases hydrolyze nitriles into carboxylic acids and/or amides, which are used in industrial chemical processes. In the present study, 26 microorganisms, including yeasts and filamentous fungi, in a minimum solid mineral medium supplemented with glucose and phenylacetonitrile were screened to evaluate their biocatalytic potential. Of these microorganisms, five fungi of the genus Aspergillus were selected and subjected to colorimetry studies to evaluate the production and distinction of nitrilase and nitrile hydratase/amidase enzymes. Aspergillus parasiticus Speare 7967 and A. niger Tiegh. 8285 produced nitrilases and nitrile hydratase, respectively. Nitrilase optimization was performed using a Box-Behnken design (BBD) and fungus A. parasiticus Speare 7967 with phenylacetonitrile volume (µl), pH, and carbohydrate source (starch:glucose; g/g) as independent variables and nitrilase activity (U ml-1 ) as dependent variable. Maximum activity (2.97 × 10-3  U ml-1 ) was obtained at pH 5.5, 80 µl of phenylacetonitrile, and 15 g of glucose. A. parasiticus Speare 7967 showed promise in the biotransformation of nitriles to carboxylic acids.


Assuntos
Aminoidrolases , Ensaios de Triagem em Larga Escala , Fungos , Nitrilas/metabolismo , Ácidos Carboxílicos/metabolismo , Aspergillus/metabolismo , Glucose
11.
Braz J Microbiol ; 52(3): 1431-1441, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33932193

RESUMO

In this study, we examined endophytic fungi in leaves of Mandevilla catimbauensis, an endemic plant species found in the Brazilian dry forest (Caatinga), and endophytic fungi's potential to produce L-asparaginase (L-ASNase). In total, 66 endophytes were isolated, and the leaf-fragment colonisation rate was 11.78%. Based on morphology, internal transcribed spacer (ITS), and partial large subunit (LSU) of ribosomal DNA sequencing, the endophytic fungi isolated belonged to six Ascomycota orders (Botryosphaeriales, Capnodiales, Diaporthales, Eurotiales, Marthamycetales, and Pleosporales). Phyllosticta species were the most frequent endophytes isolated (23 isolates [45.1%] from two species). The Shannon-Wiener and Fisher alpha index average values were 0.56 and 3.26, respectively. Twenty endophytes were randomly selected for the L-ASNase production test, of which fourteen isolates showed potential to produce the enzyme (0.48-2.22 U g-1), especially Phyllosticta catimbauensis URM 7672 (2.22 U g-1) and Cladosporium sp. G45 (2.11 U g-1). Phyllosticta catimbauensis URM 7672 was selected for the partial optimisation of L-ASNase production because of its ability to generate considerable amounts of enzyme. We obtained the highest L-ASNase activity (3.47 U g-1), representing an increase of 36.02% in enzymatic production, under the following experimental conditions: a pH of 4.2, 1.0% inoculum concentration, and 2.5% L-asparagine concentration. Our study showed that M. catimbauensis harbours an important diversity of endophytic fungi with biotechnological potential for L-ASNase production.


Assuntos
Apocynaceae , Ascomicetos , Asparaginase/biossíntese , Apocynaceae/microbiologia , Ascomicetos/classificação , Ascomicetos/metabolismo , Asparaginase/genética , Biodiversidade , Cladosporium , DNA Fúngico/genética , Endófitos/classificação , Endófitos/metabolismo , Filogenia , Folhas de Planta/microbiologia
12.
Curr Microbiol ; 78(4): 1218-1226, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33625571

RESUMO

Fusarium incarnatum-equiseti species complex (FIESC) is considered as one of the richest insecticolous species. Fusarium species synthesize toxic secondary metabolites that are not fully understood. Mycotoxin production and pathogenicity on germinating seeds, seedlings, and leaves must be carefully studied for the use of Fusarium species in the biological control of insect pests. In this study, we evaluated the mycotoxin production and phytopathogenic potential of entomopathogenic strains of Fusarium sulawesiensis (1), F. pernambucanum (3), and F. caatingaense (23). The phytopathogenicity tests of F. caatingaense (URM 6776, URM 6777, URM 6778, URM 6779, and URM 6782) were performed during the development of bean (Phaseolus vulgaris, Vigna unguiculata, and Phaseolus lunatus), and corn (Zea mays) seedlings, using four treatments (soil infestation with the inoculum, spraying on leaves, root dip, and negative control). The mycotoxins, monoacetyl-deoxynivalenols (AcDON), deoxynivalenol (DON), beauvericin (BEA), fusarenone-X (FUS), T-2 toxin (T2), diacetoxyscirpenol (DAS), and zearalenone (ZEA), were detected in the study; BEA (detected in 25 strains) and FUS (detected in 21 strains) were found to be predominant. None of the strains showed any ability to cause disease or virulence in beans and corn. The FIESC strains showed a highly variable production of mycotoxins without the potential to be used as phytopathogenic agents for the cultures tested.


Assuntos
Fusarium , Micotoxinas , Brasil , Fungos , Zea mays
13.
Prep Biochem Biotechnol ; 51(2): 164-172, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32795118

RESUMO

Lovastatin is a drug in the statin class which acts as a natural inhibitor of 3-hydroxy-3-methylglutaryl, a coenzyme reductase reported as being a potential therapeutic agent for several diseases: Alzheimer's, multiple sclerosis, osteoporosis and due to its anti-cancer properties. Aspergillus terreus is known for producing a cholesterol reducing drug. This study sets out to evaluate the production of lovastatin by Brazilian wild strains of A. terreus isolated from a biological sample and natural sources. Carbon and nitrogen sources and the best physicochemical conditions using factorial design were also evaluated. The 37 fungal were grown to produce lovastatin by submerged fermentation. A. terreus URM5579 strain was the best lovastatin producer with a level of 13.96 mg/L. Soluble starch and soybean flour were found to be the most suitable substrates for producing lovastatin (41.23 mg/L) and biomass (6.1 mg/mL). The most favorable production conditions were found in run 16 with 60 g/L soluble starch, 15 g/L soybean flour, pH 7.5, 200 rpm and maintaining the solution at 32 °C for 7 days, which led to producing 100.86 mg/L of lovastatin and 17.68 mg/mL of biomass. Using natural strains and economically viable substrates helps to optimize the production of lovastatin and promote its use.


Assuntos
Aspergillus/metabolismo , Biotecnologia/métodos , Lovastatina/biossíntese , Biomassa , Brasil , Carbono , Colesterol/química , Cromatografia Líquida de Alta Pressão , Fermentação , Concentração de Íons de Hidrogênio , Nitrogênio , Glycine max , Espectrofotometria Ultravioleta , Amido/química , Temperatura , Fatores de Tempo
14.
Biotechnol Rep (Amst) ; 28: e00552, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33294402

RESUMO

A protease from the fungus Mucor subtilissimus URM 4133, capable of producing bioactive peptides from goat casein, was purified. SDS-PAGE and zymography showed a molecular mass of 30 kDa. The enzyme was active and stable in a wide pH range (6.0-10.5) and (5.0-10.5), respectively. Optimum temperature was at 45-50 °C and stability was above 80 % (40 °C/2 h). Activity was not influenced by ions or organic substances (Triton, Tween, SDS and DMSO), but was completely inhibited by PMSF, suggesting that it belongs to the serine protease family. The Km and Vmax were 2.35 mg azocasein.mL-1 and 333.33 U.mg protein-1, respectively. Thermodynamic parameters of irreversible denaturation (40-60 °C) were enthalpy 123.63 - 123.46 kJ.mol-1, entropy 120.24-122.28 kJ.mol-1 and Gibbs free energy 85.97 - 82.45 kJ.mol-1. Any peptide sequences compatible with this protease were found after analysis by MALDI-TOF, which suggests that it is a new serine protease.

15.
PLoS One ; 15(12): e0243494, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33275627

RESUMO

Bat caves are very special roosts that harbour thousands of bats of one or more species. Such sites may hold an incredible "dark fungal diversity" which is still underestimated. We explored the culturable fungal richness in the air, on bats, and in the guano in a bat cave in Brazil's Caatinga dry forest. Fungal abundance was 683 colony-forming units (CFU) in the guano, 673 CFU in the air, and 105 CFU on the bats. Based on morphological and phylogenetic analysis of ITS, LSU, and TUB2 sequences, fungal isolates of 59 taxa belonging to 37 genera in the phyla Ascomycota (28 genera, including Aspergillus, Penicillium, Cladosporium, and Talaromyces), Basidiomycota (eight genera, including Rhodotorula and Schizophyllum), and Mucoromycota (only Rhizopus) were identified. The fungal richness in the air was 23 taxa (especially Aspergillus taxa), mainly found at 15 m and 45 m from the cave entrance; on the bodies of bats it was 36 taxa (mainly Aspergillus taxa), especially on their wing membranes (21 taxa, nine of which were exclusively found in this microhabitat); and in guano 10 fungal taxa (especially Aspergillus and Penicillium) were found. The fungal richness associated with guano (fresh and non-fresh) was similar from bats with different eating habits (insectivorous, frugivorous, and haematophagous). Sampling effort was not sufficient to reveal the total fungal taxa richness estimated. Eight (21.6%) of the 37 genera and 17 (53.1%) of the 32 identified fungal species are reported for the first time in caves. Our results highlight bat caves in Brazil as hotspots of fungal diversity, emphasizing the need to protect such special roosts.


Assuntos
Ascomicetos/isolamento & purificação , Aspergillus/isolamento & purificação , Basidiomycota/isolamento & purificação , Cavernas/microbiologia , Quirópteros/microbiologia , Animais , Ascomicetos/classificação , Ascomicetos/genética , Aspergillus/classificação , Aspergillus/genética , Basidiomycota/classificação , Basidiomycota/genética , Brasil , Quirópteros/fisiologia , DNA Ribossômico/química , DNA Ribossômico/metabolismo , Filogenia
16.
Biosci. j. (Online) ; 35(2): 419-430, mar./apr. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1048596

RESUMO

Plant growth promotion by microorganisms may be a viable alternative to increase lettuce production through pathogens control and nutrients absorption increase. Trichoderma and Pseudomonasgenus are examples of widely studied microorganisms with the capacity to promote plant growth. However, there are still gaps regarding the action of the combined effect of these two microorganisms. Therefore, the objective of this study was to evaluate the combined effect of Pseudomonas sp. UAGF14 and Trichoderma aureoviride URM5158 on the development of lettuce plants. The experimental design was completely randomized, with five treatments: CONT (control), CM (soil with organic fertilization), CMB (soil withorganic fertilization and Pseudomonas sp.), CMF (soil with organic fertilization and T. aureoviride), and CMFB (soil with organic fertilization, Pseudomonas sp. and T. aureoviride), with ten repetitions. At 30, 40 and 60 days after sowing, the following parameters were analyzed: plant and canopy height and number of leaves. At 60 days after emergence, shoot dry matter, leaf area, root dry matter, root length and chlorophyll were analyzed. Catalase, peroxidase and polyphenol oxidase enzymatic activity were determined. The CMFB treatment had the highest means of lettuce growth promotion, confirming the synergistic effect of the combination of the two microorganism types, as it increased height, canopy, shoot and root dry matter, and chlorophyll levels compared to CONT, although did not differ from CM in some variables. Enzymatic activity was also influenced by the action of these microorganisms combined, evidencing by polyphenol oxidase increase. The CMFB or CM were efficient in promoting lettuce growth, showing positive response to the plant morphological and physiological characteristics. However, few responses were observed in lettuce plant growth in the first cycle evaluated after 60 days, compared CM and CMFB treatments, but both treatments showed superiority in lettuce plant growth submitted to CONT treatment. Therefore, further studies are needed to estimate the long-term effects of combined effect of Pseudomonas sp. UAGF14 and T. aureoviride URM5158 on crop productivity in field conditions.


A promoção do crescimento das plantas por micro-organismos pode ser uma alternativa viável para aumentar a produção de alface através de controle de patógenos e aumento da absorção de nutrientes. O gênero fúngico Trichoderma e o gênero bacteriano Pseudomonas são exemplos de micro-organismos amplamente estudados com capacidade para promover o crescimento da planta. No entanto, ainda existem lacunas quanto à ação do efeito combinado desses dois micro-organismos. Portanto, o objetivo deste estudo foi avaliar o efeito combinado de Pseudomonas UAGF14 e Trichoderma aureoviride URM5158 sobre o desenvolvimento de plantas de alface. O delineamento experimental foi completamente casualizados, com cinco tratamentos: CONT (controle, sem fertilização orgânica), CM (solo com fertilização orgânica), CMB (solo com fertilização orgânicae Pseudomonas sp.), CMF (solo com fertilização orgânica e T. aureoviride) e CMFB (solo com fertilização orgânica, Pseudomonas sp. e T. aureoviride), com dez repetições. Aos 30, 40 e 60 dias após a semeadura, foram analisados os seguintes parâmetros: altura da planta e dossel e número de folhas. Aos 60 dias após a emergência, a matéria seca da parte aérea, a área foliar, a massa seca das raízes, o comprimento radicular e a clorofila foram analisados. Catalase, peroxidase e atividade enzimática da polifenol oxidase foram determinadas. O CMFB apresentou o maior crescimento de alface, confirmando o efeito benéfico da combinação dos dois tipos de micro-organismos com a planta, na medida em que aumentou a altura, o dossel, a matéria seca da parte aérea e da raiz, e os níveis de clorofila em relação ao CONT, embora não tenha diferido do CM em algumas variáveis. As atividades enzimáticas também foram influenciadas pela ação desses micro-organismos combinados, evidenciada pelo aumento de polifenol oxidase. O CMFB ou CM foram eficientes na promoção do crescimento da alface, mostrando respostas positivas às características morfológicas e fisiológicas. Entretanto, poucas respostas foram observadas no crescimento da alface noprimeiro ciclo da planta avaliado depois de 60 dias, comparando os tratamentos CM e CMFB, mas ambos tratamentos mostraram superioridade em relação ao crescimento das plantas de alface submetidas ao tratamento controle. Por isso, são necessários futuros estudos para estimar à longo prazo o efeito combinado de Pseudomonas sp. UAGF14 e Trichoderma aureoviride URM5158 na produção de cultura em condições de campo.


Assuntos
Catalase , Lactuca , Pseudomonas , Trichoderma
17.
Braz. arch. biol. technol ; 62: e19180062, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055405

RESUMO

Abstract Protein hydrolysates originating from egg white have already been reported to be bioactive and, among their biological activities, possess the antioxidant property that protects the body from early ageing and diseases linked to oxidation. Therefore, the objective of this work was to evaluate the antioxidant activity of hydrolysates obtained by the hydrolysis of egg white from hen poultry. The protease produced by Aspergillus avenaceus URM 6706 was purified and subsequently applied to hydrolysate the egg white, and the degree of hydrolysis was verified during the protease exposure time (4-24 h). The hydrolysis was intensified over time of exposure to the protease. It was possible to detect the antioxidant activities of eliminating the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) radical (ABTS•+) from 97% to 99% and 2,2-diphenyl-1-picrylhydrazyl (DPPH•) up to 27%, as well as the chelation of Cu2+ metal ions up to 62% and Fe2+ up to 54%. The elimination of ABTS•+ radical had a positive correlation with the degree of hydrolysis; however, all the other activities tested showed a negative correlation with the degree of hydrolysis. The results obtained suggest that the egg white of hen chicken represents a food source of animal origin with potential application in the functional food industry.


Assuntos
Aspergillus , Quelantes , Clara de Ovo , Peptídeo Hidrolases , Antioxidantes
18.
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
19.
Braz. j. microbiol ; 49(3): 675-682, July-Sept. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-951801

RESUMO

Abstract Aspergillus fumigatus is an opportunistic saprobe fungus that accounts for 90% of cases of pulmonary aspergillosis in immunosuppressed patients and is known for its angiotropism. When it reaches the respiratory tract, A. fumigatus interacts with structural components and blood vessels of the lungs, such as elastin. To understand the effect of this structural component, we examined the effect of elastin on the production and development of the biofilm of A. fumigatus. In RPMI containing 10 mg/mL of elastin, a significant increase (absorbance p < 0.0001; dry weight p < 0.0001) in the production of biofilm was observed in comparison to when RPMI was used alone, reaching a maximum growth of 18.8 mg (dry weight) of biofilm in 72 h. In addition, elastin stimulates the production (p = 0.0042) of extracellular matrix (ECM) and decreases (p = 0.005) the hydrophobicity during the development of the biofilm. These results suggest that elastin plays an important role in the growth of A. fumigatus and that it participates in the formation of thick biofilm.


Assuntos
Humanos , Aspergilose/metabolismo , Aspergilose/microbiologia , Aspergillus fumigatus/fisiologia , Elastina/metabolismo , Biofilmes , Matriz Extracelular/metabolismo , Aspergillus fumigatus/genética , Interações Hospedeiro-Patógeno
20.
Pesqui. vet. bras ; 38(5): 930-934, May 2018. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-955416

RESUMO

Os dermatófitos são fungos que podem causar infecções superficiais da pele, cabelo e unhas em humanos e animais. As espécies de dermatófitos mais frequentemente isoladas dos cães e gatos afetados por micoses são Microsporum gypseum e principalmente Microsporum canis. O papel crucial durante o processo de infecção é a produção de enzimas extracelulares essenciais para a invasão e estabelecimento do agente patogênico no tecido do hospedeiro. O objetivo deste trabalho foi isolar dermatófitos de cães e gatos e avaliar o perfil enzimático dos isolados obtidos. Amostras de pelos e escamas epidérmicas foram coletadas de cães e gatos em instalações veterinárias em Recife/PE, e os isolados foram identificados com base nas características macroscópicas e microscópicas. A análise qualitativa das enzimas urease, protease, lipase, colagenase e fosfolipase foi avaliada a partir dos dermatófitos isolados. Durante 10 meses, um total de 106 animais, que compreendeu de 99 cães e sete gatos com sinais clínicos, independentemente do sexo e raça foram avaliados. Apenas oito animais foram confirmados com dermatofitose, principalmente cães (n=7), sendo seis afetados por M. canis e um por M. gypseum, a raça mais afetada foi Yorkshire (n=3). No entanto, apenas um gato foi confirmado com M. canis. Não foi observada predisposição relacionada ao sexo quanto à ocorrência de dermatofitose nos cães e gatos avaliados. Os dermatófitos isolados apresentaram perfis semelhantes para as enzimas urease, lipase, protease, fosfolipase e colagenase, característica importante em infecções patogênicas. O diagnóstico clínico destas zoonoses com base na confirmação microbiológica e uma compreensão dos mecanismos subjacentes é de grande importância para o tratamento e prevenção de doenças fúngicas em animais.(AU)


Dermatophytes are fungi that can cause superficial infections of the skin, hair and nails in man and animals. The most frequent dermatophyte species isolated from dogs and cats are Microsporum gypseum, most notably Microsporum canis. The crucial role during the infection process is the production of extracellular enzymes essential for the invasion and establishment of the pathogen in the host tissue. The objective of this research was to isolate dermatophytes from dogs and cats and evaluate the enzymatic profile of the isolates obtained. Hair samples and epidermal scales were collected from dogs and cats in veterinary facilities in Recife-PE, and the isolates were identified based on macroscopic and microscopic characteristics. The qualitative analysis of the enzymes urease, protease, lipase, collagenase and phospholipase was evaluated from the isolated dermatophytes. During 10 months, a total of 106 animals, comprising of 99 dogs and seven cats with clinical signs, regardless of sex and race were evaluated. Only eight animals were confirmed with dermatophytosis, mostly dogs (n=7), being six affected by M. canis and one by M. gypseum, the race most affected was Yorkshire (n=3). However, only one cat was confirmed with M. canis. No sex-related predisposition was observed regarding the occurrence of dermatophytosis in dogs and cats evaluated. Isolated dermatophytes showed similar profiles for the enzymes urease, lipase, protease, phospholipase and collagenase, important characteristic for pathogenic infections. The diagnosis of this zoonosis based on microbiological confirmation and a better understanding of the underlying mechanisms is of great importance for the treatment and prevention of fungal diseases in animals.(AU)


Assuntos
Animais , Gatos , Cães , Tinha/enzimologia , Gatos/microbiologia , Cães/microbiologia , Microsporum/isolamento & purificação
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