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1.
Food Sci Biotechnol ; 27(5): 1485-1492, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30319859

RESUMO

This study examined the biological functions of the butanol extracts of green pine cones (GPCs) that had not ripened completely. The butanol extracts of GPC showed 78.22% DPPH-scavenging activity, 53.55% TEAC and 71.50% hyaluronidase (HAase) inhibition activity. They also exhibited inhibition activity against food poisoning microorganisms. The contents of total phenolic compounds and total flavonoids were 296.75 and 26.07 mg/g, respectively. Biologically active compounds were analyzed and separated using HPLC related to the DPPH-scavenging and HAase inhibition activities. Gallotannin was the primary biologically active compound with DPPH-scavenging and HAase inhibition activities in the GPC butanol extracts.

2.
J Microbiol Biotechnol ; 27(4): 701-708, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28189140

RESUMO

This study was conducted to evaluate the hyaluronidase (HAase) inhibition activity of Asparagus cochinchinesis (AC) extracts following fermentation by Weissella cibaria through response surface methodology. To optimize the HAase inhibition activity, a central composite design was introduced based on four variables: the concentration of AC extract (X1: 1-5%), amount of starter culture (X2: 1-5%), pH (X3: 4-8), and fermentation time (X4: 0-10 days). The experimental data were fitted to quadratic regression equations, the accuracy of the equations was analyzed by ANOVA, and the regression coefficients for the surface quadratic model of HAase inhibition activity in the fermented AC extract were estimated by the F test and the corresponding p values. The HAase inhibition activity indicated that fermentation time was most significant among the parameters within the conditions tested. To validate the model, two different conditions among those generated by the Design Expert program were selected. Under both conditions, predicted and experimental data agreed well. Moreover, the content of protodioscin (a well-known compound related to anti-inflammation activity) was elevated after fermentation of the AC extract at the optimized fermentation condition.


Assuntos
Asparagus/enzimologia , Fermentação , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Extratos Vegetais/farmacologia , Weissella/metabolismo , Análise de Variância , Anti-Inflamatórios/farmacologia , Asparagus/química , Asparagus/microbiologia , Cromatografia Líquida de Alta Pressão/métodos , Diosgenina/análogos & derivados , Diosgenina/farmacologia , Concentração de Íons de Hidrogênio , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Saponinas/farmacologia , Weissella/crescimento & desenvolvimento
3.
J Microbiol Biotechnol ; 26(9): 1527-32, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27238939

RESUMO

Strain SPF4211, having hyaluronidase (HAase) inhibition activity, was isolated from P. davidiana (Carriere) Franch fruit (PrDF) sugar extract. The phenotypic and biochemical properties based on 16S rDNA sequencing and an API 50 CHB kit suggested that the organism was B. subtilis. To optimize the HAase inhibition activity of PrDF extract by fermentation of strain SPF4211, a central composite design (CCD) was introduced based on three variables: concentration of PrDF extract (X1: 1-5%), amount of starter culture (X2: 1-5%), and fermentation time (X3: 0-7 days). The experimental data were fitted with quadratic regression equations, and the accuracy of the equations was analyzed by ANOVA. The statistical model predicted the highest HAase inhibition activity of 37.936% under the optimal conditions of X1 = 1%, X2 = 2.53%, and X3 = 7 days. The optimized conditions were validated by observation of an actual HAase inhibition activity of 38.367% from extract of PrDF fermented by SPF4211. These results agree well with the predicted model value.


Assuntos
Bacillus subtilis/metabolismo , Frutas/enzimologia , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Extratos Vegetais/farmacologia , Prunus/enzimologia , Fermentação , Frutas/química , Frutas/metabolismo , Frutas/microbiologia , Prunus/química , Prunus/metabolismo , Prunus/microbiologia
4.
Talanta ; 94: 348-52, 2012 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-22608459

RESUMO

The electrical explosion of Fe wire in air produced nanoparticles containing the binary mixture of magnetite (Fe(3)O(4)) and maghemite (γ-Fe(2)O(3)). The phase identification of magnetite and maghemite by the conventional X-ray diffraction method is not a simple matter because both have the same cubic structure and their lattice parameters are almost identical. Here, we propose a convenient method to assess the presence of magnetite-maghemite mixture and to further quantify its phase composition using the conventional peak deconvolution technique. A careful step scan around the high-angle peaks as (511) and (440) revealed the clear doublets indicative of the mixture phases. The quantitative analysis of the mixture phase was carried out by constructing a calibration curve using the pure magnetite and maghemite powders commercially available. The correlation coefficients, R(2), for magnetite-maghemite mixture was 0.9941. According to the method, the iron oxide nanoparticles prepared by the wire explosion in this study was calculated to contain 55.8 wt.% maghemite and 44.2 wt.% magnetite. We believe that the proposed method would be a convenient tool for the study of the magnetite-maghemite mixture which otherwise requires highly sophisticated equipments and techniques.


Assuntos
Compostos Férricos/análise , Óxido Ferroso-Férrico/análise , Ferro/química , Nanopartículas/análise , Eletricidade , Explosões , Compostos Férricos/química , Óxido Ferroso-Férrico/química , Nanopartículas/química , Tamanho da Partícula , Pós , Difração de Raios X
5.
J Nanosci Nanotechnol ; 11(8): 7258-60, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22103171

RESUMO

TiCu nanopowder was produced using an electrical wire explosion method and subsequently consolidated into dense nanostuctured TiCu by a high frequency induction heated sintering method. The consolidation was accomplished by the combination of an induced current and a high mechanical pressure within two minutes. This process results in very quick densification to near the theoretical density and prohibits grain growth in nano-structured materials. The grain sizes and mechanical properties of the sintered TiCu were investigated.

6.
J Colloid Interface Sci ; 356(1): 311-5, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21276975

RESUMO

Sodium laurylsulfate (SLS), an anionic surfactant, was used for tailoring calcite via a solution route. SLS was dissolved in calcium and carbonate source solutions at various concentrations and critical micelle concentrations (CMCs). The crystallized particles were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), laser-scattering particle size measurements, and thermogravimetric analysis (TGA). Energy dispersive spectroscopy (EDS) analysis was carried out to measure sulfur profiles on the surface of the particles. SLS tended to produce small calcite particles in the carbonate source solution, whereas this effect was not obvious in the calcium source solution. It is believed that the electrostatic repulsion force in the carbonate source solution contributes to the different particle refining effects of SLS seen in the two solutions.


Assuntos
Carbonato de Cálcio/química , Dodecilsulfato de Sódio/química , Cálcio/química , Carbonatos/química , Cristalização , Concentração de Íons de Hidrogênio , Micelas , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Soluções/química , Espectrometria por Raios X , Enxofre/química , Tensoativos , Termogravimetria , Difração de Raios X
7.
Waste Manag ; 29(3): 1132-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18835149

RESUMO

Printed circuit boards incorporated in most electrical and electronic equipment contain valuable metals such as Cu, Ni, Au, Ag, Pd, Fe, Sn, and Pb. In order to employ a hydrometallurgical route for the recycling of valuable metals from printed circuit boards, a mechanical pre-treatment step is needed. In this study, the metallic components from waste printed circuit boards have been enriched using a mechanical separation process. Waste printed circuit boards shredded to <10mm were milled using a stamp mill to liberate the various metallic components, and then the milled printed circuit boards were classified into fractions of <0.6, 0.6-1.2, 1.2-2.5, 2.5-5.0, and >5.0mm. The fractions of milled printed circuit boards of size <5.0mm were separated into a light fraction of mostly non-metallic components and a heavy fraction of the metallic components by gravity separation using a zig-zag classifier. The >5.0mm fraction and the heavy fraction were subjected to two-step magnetic separation. Through the first magnetic separation at 700 Gauss, 83% of the nickel and iron, based on the whole printed circuit boards, was recovered in the magnetic fraction, and 92% of the copper was recovered in the non-magnetic fraction. The cumulative recovery of nickel-iron concentrate was increased by a second magnetic separation at 3000 Gauss, but the grade of the concentrate decreased remarkably from 76% to 56%. The cumulative recovery of copper concentrate decreased, but the grade increased slightly from 71.6% to 75.4%. This study has demonstrated the feasibility of the mechanical separation process consisting of milling/size classification/gravity separation/two-step magnetic separation for enriching metallic components such as Cu, Ni, Al, and Fe from waste printed circuit boards.


Assuntos
Conservação dos Recursos Naturais , Eletrônica , Resíduos Industriais , Teste de Materiais , Fenômenos Mecânicos , Metais/química , Eliminação de Resíduos , Magnetismo , Tamanho da Partícula
8.
J Hazard Mater ; 124(1-3): 230-5, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-15964139

RESUMO

A diffusion dialysis method using anion exchange membrane was used to recover H2SO4 from waste sulfuric acid solution produced at the diamond manufacturing process. Effects of flow rate, operation temperature, and metal ion concentration on the recovery of H2SO4 were investigated. The recovery of H2SO4 increased with the concentration of H2SO4 and operation temperature. It also increased with the flow rate ratio of water/H2SO4 solution up to 1, above which no further increase was observed. The flow rate did not affect the rejection of Fe and Ni ions. About 80% of H2SO4 could be recovered from waste sulfuric acid which contained 4.5M free-H2SO4 at the flow rate of 0.26x10(-3) m3/hm3. The concentration of recovered H2SO4 was 4.3M and the total impurity was 2000 ppm. Preliminary economic evaluation has revealed that the dialysis system is highly attractive one that has payback period of only few months.


Assuntos
Resíduos Perigosos/prevenção & controle , Ácidos Sulfúricos/isolamento & purificação , Antiporters , Análise Custo-Benefício , Diálise/economia , Diálise/métodos , Difusão , Metais/química , Concentração Osmolar , Temperatura
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