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1.
An Acad Bras Cienc ; 95(suppl 1): e20220178, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37466533

RESUMO

The antibacterial secondary metabolites of the fungus Penicillium chrysogenum associated with the beetle Aspongopus chinensis were investigated through chromatographic fractionation methods of ethyl acetate extracts of the fungal cultures. Five compounds were isolated, and their structures were determined as emodin, 4-(methoxymethyl)benzoic acid, isoochracinic acid, secalonic acid D, and dicerandrol A using mass spectroscopy and nuclear magnetic resonance spectroscopic analyses. Emodin exhibited strong antimicrobial activity, especially against Staphylococcus aureus even when growing on cooked pork, with a minimal inhibitory concentration (MIC) of 6.3 µg/mL. Dimeric tetrahydroxanthones, such as secalonic acid D and dicerandrol A, also exhibited potent activity, with MIC values ranging from 9.5 to 28.5 µg/mL. In summary, P. chrysogenum was isolated as a symbiotic fungus of the beetle A. chinensis for the first time and this strain could generate antibacterial secondary metabolites, which could potently inhibit gram-positive bacteria growth in vitro.


Assuntos
Besouros , Emodina , Penicillium chrysogenum , Penicillium , Animais , Penicillium chrysogenum/química , Antibacterianos , Staphylococcus aureus , Testes de Sensibilidade Microbiana
2.
An Acad Bras Cienc ; 92 Suppl 2: e20180838, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32725044

RESUMO

In this study, the effects of Tween 40 and ethanol supplementation on the secretion, structure and antioxidant activities of exopolysaccharide (EPS) from Inonotus rickii were investigated. It was observed that Tween 40 and ethanol displayed a stimulatory effect on EPS secretion. The EPSs obtained by the addition of Tween 40 (EPS-T), ethanol (EPS-E) and control (EPS-C) were purified by Sepharose CL-6B gel chromatography and molecular weights of EPS-T, EPS-E and EPS-C were estimated to be 22.1, 30.0, and 40.5 kDa, respectively. Monosaccharide composition analysis indicated that EPS-T, EPS-E and EPS-C were mainly composed of mannose and glucose. Furthermore, EPS-E exhibited better OH• and DPPH scavenging activities than those of EPS-C and EPS-T, which might be associated with its molecular characterization.


Assuntos
Antioxidantes , Etanol , Polissacarídeos Bacterianos , Polissorbatos , Polissorbatos/toxicidade
3.
Braz J Microbiol ; 50(3): 625-632, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31030410

RESUMO

The effects of different three carbon sources, that is, glucose, fructose, and sucrose, on production, molecular properties and antiproliferative activity of exopolysaccharide (EPS), were evaluated in the submerged culture of Scleroderma areolatum Ehrenb. Among carbon sources examined, the addition of sucrose maximizes the mycelia production, while fructose could maximize the EPS yield. Although the predominant carbohydrate compositions identified were gluconic acid and mannose, the monosaccharide composition of EPSs was also different significantly. FT-IR spectral analysis revealed there was no significant difference among the prominent characteristic groups in three EPSs. The molecular weight of EPSs was also affected by carbon source, being generally lower compared with that with glucose. However, all EPSs molecule existed as nearly globular shape form in aqueous solution. The variation of carbon sources also affected antiproliferative activity examined in vitro using cell proliferation assay. Fructose was optimal carbon source giving higher antiproliferative activity probably due to the relatively high contents of xylose in the EPS with low molecular weight.


Assuntos
Basidiomycota/metabolismo , Carbono/metabolismo , Inibidores do Crescimento/química , Inibidores do Crescimento/farmacologia , Polissacarídeos/química , Polissacarídeos/farmacologia , Basidiomycota/química , Basidiomycota/crescimento & desenvolvimento , Carbono/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura/química , Meios de Cultura/metabolismo , Inibidores do Crescimento/metabolismo , Humanos , Peso Molecular , Polissacarídeos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
4.
An Acad Bras Cienc ; 89(3 Suppl): 2033-2041, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29044312

RESUMO

The effect on different three carbon source (i.e. glucose, fructose and sucrose) on production, chemical characterization and antioxidant activity of exopolysaccharide (EPS) produced by Phellinus vaninii Ljup was investigated in this study. Amongst carbon sources examined, glucose and sucrose were favorable for the mycelia growth, while the maximum EPS yield was achieved when sucrose was employed. The predominant carbohydrate compositions in EPSs identified were gluconic acid, glucose, mannose and galactose acid. Then, FT-IR spectral analysis revealed prominent characteristic groups in EPSs. EPSs molecule exist as nearly globular shape form in aqueous solution. The variation also affects antioxidant activities by investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was best carbon source from the viewpoint of antioxidant activity due to the relatively high contents of galactose in the EPS with moderate molecular weight and polydispersity.


Assuntos
Carbono/metabolismo , Polissacarídeos Fúngicos , Polissacarídeos Bacterianos/metabolismo , Frutose/metabolismo , Glucose/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Sacarose/metabolismo
5.
An Acad Bras Cienc ; 89(1 Suppl 0): 383-390, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28492733

RESUMO

A simple and sensitive method for simultaneous determination of furan and vinyl acetate (VA) in vapor phase of mainstream cigarette smoke with cold trap and gas chromatography-mass spectrometry (GC-MS) was developed. A Cambridge filter pad (CFP) was placed in front of the impingers of smoking machine to remove the particle phase from cigarette smoke. Furan and VA in vapor phase of mainstream cigarette smoke were collected in two impingers connected in series by filled with methanol at -78°C. The solutions were added with deuterium-labeled furan-d4 and VA-d6 as internal standards and analyzed by GC-MS. The results showed that the calibration curves for furan and VA were linear (r2 > 0.9995) over the studied concentration range. The intra- and inter-day precision values for furan and VA were <7.07% and <9.62%, respectively. The extraction recoveries of furan and VA were in the range of 94.5-97.7% and 92.3-94.9%, respectively. Moreover, the limits of detection for furan and VA were 0.028 µg mL-1 and 1.3 ng mL-1, respectively. The validated method has been successfully applied to determine the emissions of furan and VA in the vapor phase of mainstream cigarette smoke under International Organization for Standardization (ISO) and Canadian Intense (CI) smoking regimen.


Assuntos
Furanos/análise , Fumaça/análise , Compostos de Vinila/análise , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Reprodutibilidade dos Testes
6.
An. acad. bras. ciênc ; 89(1,supl): 383-390, May. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886664

RESUMO

ABSTRACT A simple and sensitive method for simultaneous determination of furan and vinyl acetate (VA) in vapor phase of mainstream cigarette smoke with cold trap and gas chromatography-mass spectrometry (GC-MS) was developed. A Cambridge filter pad (CFP) was placed in front of the impingers of smoking machine to remove the particle phase from cigarette smoke. Furan and VA in vapor phase of mainstream cigarette smoke were collected in two impingers connected in series by filled with methanol at -78°C. The solutions were added with deuterium-labeled furan-d4 and VA-d6 as internal standards and analyzed by GC-MS. The results showed that the calibration curves for furan and VA were linear (r2 > 0.9995) over the studied concentration range. The intra- and inter-day precision values for furan and VA were <7.07% and <9.62%, respectively. The extraction recoveries of furan and VA were in the range of 94.5-97.7% and 92.3-94.9%, respectively. Moreover, the limits of detection for furan and VA were 0.028 µg mL-1 and 1.3 ng mL-1, respectively. The validated method has been successfully applied to determine the emissions of furan and VA in the vapor phase of mainstream cigarette smoke under International Organization for Standardization (ISO) and Canadian Intense (CI) smoking regimen.


Assuntos
Fumaça/análise , Compostos de Vinila/análise , Furanos/análise , Calibragem , Reprodutibilidade dos Testes , Cromatografia Gasosa-Espectrometria de Massas
7.
An. acad. bras. ciênc ; 89(3,supl): 2033-2041, 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886795

RESUMO

ABSTRACT The effect on different three carbon source (i.e. glucose, fructose and sucrose) on production, chemical characterization and antioxidant activity of exopolysaccharide (EPS) produced by Phellinus vaninii Ljup was investigated in this study. Amongst carbon sources examined, glucose and sucrose were favorable for the mycelia growth, while the maximum EPS yield was achieved when sucrose was employed. The predominant carbohydrate compositions in EPSs identified were gluconic acid, glucose, mannose and galactose acid. Then, FT-IR spectral analysis revealed prominent characteristic groups in EPSs. EPSs molecule exist as nearly globular shape form in aqueous solution. The variation also affects antioxidant activities by investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was best carbon source from the viewpoint of antioxidant activity due to the relatively high contents of galactose in the EPS with moderate molecular weight and polydispersity.


Assuntos
Polissacarídeos Bacterianos/metabolismo , Carbono/metabolismo , Polissacarídeos Fúngicos , Sacarose/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Frutose/metabolismo , Glucose/metabolismo
8.
An Acad Bras Cienc ; 88 Suppl 1: 479-87, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27142550

RESUMO

A soil isolate, Penicillium janthinellum sw09 has been found to produce significant amounts of an extracellular pectinase subsequently characterized as exo-polygalacturonase (exo-PG). By optimizing growth conditions, P. janthinellum sw09 produced high amount of exo-PG (16.54 units/mL). The crude enzyme was purified by gel filtration chromatography and two exo-PG activity peaks (designated as PGI and PGII) were revealed. On SDS-PAGE analysis, purified PGII using DEAE-Sepharose FF column, was found to be a single band with a molecular mass of 66.2 kDa. The purified PGII exhibited maximal activity at the temperature of 45 oC and pH 5.0. The stability profiles show that PGII is more stable in the pH range of 4.0-8.0 and below 60 oC. The Km and Vmax for the enzyme was 1.74 mg/mL and 18.08 µmol/ (mL•min), respectively. Due to this enzymatic characterization, this pectinase is an attractive candidate for applications in degradation of pectin.


Assuntos
Penicillium/enzimologia , Poligalacturonase/biossíntese , Eletroforese em Gel de Poliacrilamida , Concentração de Íons de Hidrogênio , Penicillium/crescimento & desenvolvimento , Poligalacturonase/química , Poligalacturonase/isolamento & purificação , Temperatura
9.
An Acad Bras Cienc ; 87(2): 997-1005, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26062117

RESUMO

The aim of the study was to investigate the effect of cigarette smoke on the production and characterization of exopolysaccharides (EPSs) produced by Bifidobacterium. Cigarettes of Shanhua brand (nicotine: 1.1 mg, tar: 11 mg) were utilized to prepare a cigarette smoke condensate (CSC). The standard strain of Bifidobacterium animalis was cultured in MRS media under anaerobic addition of CSC. The results showed that CSC significantly decreased the growth of B. animalis as well as EPSs and acetic acid production. Furthermore, two EPSs fractions (Fr-I and Fr-II) were isolated and purified for chemical and molecular determination. By comparison with control, CSC was found to be of great impact on EPSs carbohydrate composition. The molecular weight mass of Fr-I changed from 3.33 × 10(5) g/mol (without CSC) to 2.99 × 10(5) (with CSC). In conclusion, in vitro studies revealed that CSC was directly able to affect the production of metabolites for B. animalis, which could be an essential factor in certain pathological disorders.


Assuntos
Bifidobacterium/química , Polissacarídeos Bacterianos , Poluição por Fumaça de Tabaco , Bifidobacterium/crescimento & desenvolvimento
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