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1.
Int J Med Mushrooms ; 25(3): 37-46, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37017660

RESUMO

This study was conducted to evaluate extraction yield, antioxidant content, antioxidant capacity and antibacterial activity of extracts obtained from submerged mycelium (ME) and fruiting body (FBE) of Phellinus robiniae NTH-PR1. The results showed that yields of ME and FBE reached 14.84 ± 0.63 and 18.89 ± 0.86%, respectively. TPSC, TPC, and TFC were present in both mycelium and fruiting body, and the more contents of them were found in fruiting body. The concentrations of TPSC, TPC and TFC in ME and FBE were 17.61 ± 0.67 and 21.56 ± 0.89 mg GE g-1, 9.31 ± 0.45 and 12.14 ± 0.56 mg QAE g-1, and 8.91 ± 0.53 and 9.04 ± 0.74 mg QE g-1, respectively. EC50 values for DPPH radical scavenging revealed FBE (260.62 ± 3.33 µg mL-1) was more effective than ME (298.21 ± 3.61 µg mL-1). EC50 values for ferrous ion chelating in ME and FBE were 411.87 ± 7.27 and 432.39 ± 2.23 µg mL-1, respectively. Thus, both extracts were able to inhibit Gram-positive and Gram-negative pathogenic bacterial strains, at concentrations ranging in 25-100 mg mL-1 of ME and 18.75-75 mg mL-1 of FBE for Gram-positive bacteria; ranging in 75-100 mg mL-1 of ME and 50-75 of FBE for Gram-negative bacteria. Overall submerged mycelial biomass and fruiting bodies of Ph. robiniae NTH-PR1 can be considered as useful natural sources for development of functional food, pharmaceuticals and cosmetic products or cosmeceuticals.


Assuntos
Agaricales , Anti-Infecciosos , Ascomicetos , Basidiomycota , Agaricales/química , Antioxidantes/farmacologia , Anti-Infecciosos/farmacologia , Micélio/química , Carpóforos/química
2.
J Mol Model ; 28(3): 54, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35128580

RESUMO

Gold and gold-based clusters are still receiving special attention owing to their diverse applicability. Density functional theory (DFT) calculations were employed to investigate the structures, the lone-pair affinity of some small Aun clusters (n = 16, 17, and the effects of chromium dopant on their properties. Regarding Au16, the boat-like Cs conformation and the hollow Td form are found to be energetically quasi-degenerate and strongly competing as the ground state. In terms of Au17, a star-like cage is computed to be more stable than the putative global minimum reported in preceding studies. Given Au16Cr isomer, a novel structure for the lowest energy is proposed. Binding energies of these species with CO, NH3, and PH3 ligands are also provided as an in-depth reference to the literature. Present results altogether encourage further theoretical implementations, e.g., CCSD(T) and experimental probes, e.g., the infrared, to validate the findings, thus harnessing the potentiality of the complexes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-25546493

RESUMO

The application of chemometrics-assisted UV spectrophotometry and RP-HPLC to the simultaneous determination of chloramphenicol, dexamethasone and naphazoline in ternary and quaternary mixtures is presented. The spectrophotometric procedure is based on the first-order derivative and wavelet transforms of ratio spectra using single, double and successive divisors. The ratio spectra were differentiated and smoothed using Savitzky-Golay filter; whereas wavelet transform realized with wavelet functions (i.e. db6, gaus5 and coif3) to obtain highest spectral recoveries. For the RP-HPLC procedure, the separation was achieved on a ZORBAX SB-C18 (150×4.6 mm; 5 µm) column at ambient temperature and the total run time was less than 7 min. A mixture of acetonitrile - 25 mM phosphate buffer pH 3 (27:73, v/v) was used as the mobile phase at a flow rate of 1.0 mL/min and the effluent monitored by measuring absorbance at 220 nm. Calibration graphs were established in the range 20-70 mg/L for chloramphenicol, 6-14 mg/L for dexamethasone and 3-8 mg/L for naphazoline (R(2)>0.990). The RP-HPLC and ratio spectra transformed by a combination of derivative-wavelet algorithms proved to be able to successfully determine all analytes in commercial eye drop formulations without sample matrix interference (mean percent recoveries, 97.4-104.3%).


Assuntos
Cloranfenicol/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Dexametasona/análise , Nafazolina/análise , Raios Ultravioleta , Análise de Ondaletas , Calibragem , Cloranfenicol/química , Dexametasona/química , Nafazolina/química , Soluções Oftálmicas , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta
4.
ScientificWorldJournal ; 2014: 313609, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24949492

RESUMO

The application of first-order derivative and wavelet transforms to UV spectra and ratio spectra was proposed for the simultaneous determination of ibuprofen and paracetamol in their combined tablets. A new hybrid approach on the combined use of first-order derivative and wavelet transforms to spectra was also discussed. In this application, DWT (sym6 and haar), CWT (mexh), and FWT were optimized to give the highest spectral recoveries. Calibration graphs in the linear concentration ranges of ibuprofen (12-32 mg/L) and paracetamol (20-40 mg/L) were obtained by measuring the amplitudes of the transformed signals. Our proposed spectrophotometric methods were statistically compared to HPLC in terms of precision and accuracy.


Assuntos
Acetaminofen/análise , Ibuprofeno/análise , Espectrofotometria Ultravioleta/métodos , Comprimidos/química , Análise de Ondaletas
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