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1.
PLoS One ; 15(1): e0227489, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929553

RESUMO

Particle size is one factor affecting phosphorus (P) dynamics in soils and sediments. This study investigated how flow facilitated by hydraulic pumps and aquatic vegetation species water lettuce (Pistia stratiotes) and water hyacinth (Eichhornia crassipes) affected particle size and P-dynamics in organic sediments in agricultural drainage ditches. Sediments with finer particle size (>0.002 mm) were hypothesized to contain greater total P (TP) and less labile P than sediments with coarser particle size. Particle size was determined using a LS 13 320 Laser Diffraction Particle Size Analyzer. Sediments were tested for pH, TP, and organic matter. Fractions of P were determined using a sequential fractionation experiment and 31P Nuclear Magnetic Resonance (NMR) Spectroscopy. Larger average particle size and lower average total P concentrations were found in the inflows of the field ditches compared to the outflows. Presence of flow and aquatic vegetation did not have a significant impact on particle size, TP, or labile P fractions. Median (p = 0.10) particle size was not significantly correlated to TP. Overall, there was an average trend of coarser particle size and lower P concentrations in the inflow compared to the outflow. The presence of inorganic limerock could have affected results due to increased P adsorption capacity and larger average particle size compared to the organic fraction of the sediment.


Assuntos
Agricultura , Sedimentos Geológicos/química , Fósforo/química , Hyacinthus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Alface/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Compostos Orgânicos/química , Tamanho da Partícula , Solo/química , Movimentos da Água
2.
Molecules ; 24(8)2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31013599

RESUMO

Flavonols are important copigments that affect flower petal coloration. Flavonol synthase (FLS) catalyzes the conversion of dihydroflavonols to flavonols. In this study, we identified a FLS gene, MaFLS, expressed in petals of the ornamental monocot Muscari aucheri (grape hyacinth) and analyzed its spatial and temporal expression patterns. qRT-PCR analysis showed that MaFLS was predominantly expressed in the early stages of flower development. We next analyzed the in planta functions of MaFLS. Heterologous expression of MaFLS in Nicotiana tabacum (tobacco) resulted in a reduction in pigmentation in the petals, substantially inhibiting the expression of endogenous tobacco genes involved in anthocyanin biosynthesis (i.e., NtDFR, NtANS, and NtAN2) and upregulating the expression of NtFLS. The total anthocyanin content in the petals of the transformed tobacco plants was dramatically reduced, whereas the total flavonol content was increased. Our study suggests that MaFLS plays a key role in flavonol biosynthesis and flower coloration in grape hyacinth. Moreover, MaFLS may represent a new potential gene for molecular breeding of flower color modification and provide a basis for analyzing the effects of copigmentation on flower coloration in grape hyacinth.


Assuntos
Flavonóis/biossíntese , Flores , Hyacinthus , Oxirredutases , Pigmentação/fisiologia , Proteínas de Plantas , Antocianinas/genética , Flavonóis/genética , Flores/enzimologia , Flores/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Hyacinthus/enzimologia , Hyacinthus/genética , Oxirredutases/biossíntese , Oxirredutases/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Tabaco/enzimologia , Tabaco/genética
3.
Chemosphere ; 233: 993-994, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30471950

RESUMO

A mistake of using pseudo-first-order kinetic equation for testing kinetic parameters of adsorption has been pointed out, as well as inappropriate citations for the adsorption kinetic models. Further, this discussion gives a correct pseudo-first-order kinetic equation and makes a suggestion for citing the original papers for the pseudo-second-order and intra-particle diffusion kinetic equations.


Assuntos
Eichhornia , Hyacinthus , Nanopartículas , Poluentes Químicos da Água/análise , Óxido de Zinco , Adsorção , Carvão Vegetal , Cromo , Cinética , Águas Residuárias
4.
Chemosphere ; 206: 387-397, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29754063

RESUMO

Coral embryos are a critical and sensitive period for the early growth and development of coral. Benzo(a)pyrene (BaP) is widely distributed in the ocean and has strong toxicity, but there is little information on the toxic effects to coral embryos exposed to this widespread environmental contaminant. Thus, in this study, we utilized the Illumina Hiseq™ 4000 platform to explore the gene response of Acropora hyacinthus embryos under the BaP stress. A total of 130,042 Unigenes were obtained and analyzed, and approximately 37.67% of those matched with sequences from four different species. In total, 2606 Unigenes were up-regulated, and 3872 Unigenes were down-regulated. After Gene Ontology (GO) annotation, the results show that the "cellular process" and "metabolic process" were leading in the category of biological processes, which the "binding" and "catalytic activity" were the most abundant subcategories in molecular function. Based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the most differentially expressed genes (DEGs) were enriched, as well as down-regulated in the pathways of oxidative phosphorylation, metabolism of xenobiotics, immune-related genes, apoptosis and human disease genes. At the same time, 388,197 of Single-nucleotide Polymorphisms (SNPs) and 6164 of Simple Sequence Repeats (SSRs) were obtained, which can be served as the richer and more valuable SSRs molecular markers in the future. The results of this study can help to better understand the toxicological mechanism of coral embryo exposed to BaP, and it is also essential for the protection and restoration of coral reef ecosystem in the future.


Assuntos
Benzo(a)pireno/efeitos adversos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Hyacinthus/embriologia , Ativação Transcricional/fisiologia , Animais
5.
Sci Rep ; 8(1): 7875, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29777196

RESUMO

Pollen tubes are used as models in studies on the type of tip-growth in plants. They are an example of polarised and rapid growth because pollen tubes are able to quickly invade the flower pistil in order to accomplish fertilisation. How different ionic fluxes are perceived, processed or generated in the pollen tube is still not satisfactorily understood. In order to measure the H+, K+, Ca2+ and Cl- fluxes of a single pollen tube, we developed an Electrical Lab on a Photovoltaic-Chip (ELoPvC) on which the evolving cell was immersed in an electrolyte of a germination medium. Pollen from Hyacinthus orientalis L. was investigated ex vivo. We observed that the growing cell changed the (redox) potential in the medium in a periodic manner. This subtle measurement was feasible due to the effects that were taking place at the semiconductor-liquid interface. The experiment confirmed the existence of the ionic oscillations that accompany the periodic extension of pollen tubes, thereby providing - in a single run - the complete discrete frequency spectrum and phase relationships of the ion gradients and fluxes, while all of the metabolic and enzymatic functions of the cell life cycle were preserved. Furthermore, the global 1/fα characteristic of the power spectral density, which corresponds to the membrane channel noise, was found.


Assuntos
Eletrólitos/análise , Hyacinthus/metabolismo , Pólen/química , Semicondutores , Cálcio/química , Cálcio/metabolismo , Cloretos/química , Cloretos/metabolismo , Eletrólitos/química , Eletrólitos/metabolismo , Germinação , Íons/metabolismo , Dispositivos Lab-On-A-Chip , Oxirredução , Pólen/crescimento & desenvolvimento , Pólen/metabolismo , Tubo Polínico/química , Tubo Polínico/metabolismo , Potássio/química , Potássio/metabolismo
6.
Molecules ; 23(4)2018 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-29649162

RESUMO

The physiological responses to estrogen hormones are mediated within specific tissues by at least two distinct receptors, ER and ER. Several natural and synthetic molecules show activity by interacting with these proteins. In particular, a number of vegetal compounds known as phytoestrogens shows estrogenic or anti-estrogenic activity. The majority of these compounds belongs to the isoflavones family and the most representative one, genistein, shows anti-proliferative effects on various hormone-sensitive cancer cells, including breast, ovarian and prostate cancer. In this work we describe the identification of structurally related homoisoflavones isolated from Leopoldia comosa (L.) Parl. (L. comosa), a perennial bulbous plant, potentially useful as hormonal substitutes or complements in cancer treatments. Two of these compounds have been selected as potential ligands of estrogen receptors (ERs) and the interaction with both isoforms of estrogen receptors have been investigated through molecular docking on their crystallographic structures. The results provide evidence of the binding of these compounds to the target receptors and their interactions with key residues of the active sites of the two proteins, and thus they could represent suitable leads for the development of novel tools for the dissection of ER signaling and the development of new pharmacological treatments in hormone-sensitive cancers.


Assuntos
Hyacinthus/química , Isoflavonas/química , Receptores Estrogênicos/metabolismo , Domínio Catalítico/efeitos dos fármacos , Isoflavonas/farmacologia , Modelos Moleculares , Simulação de Acoplamento Molecular , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Receptores Estrogênicos/química
7.
Bioresour Technol ; 257: 157-163, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29499497

RESUMO

A complex of water-hyacinth derived pellets immobilized with Chlorella sp. was applied, for the first time, in the bioremediation of Cadmium (Cd). The Cd(II) removal efficiency of the complex was optimized by investigating several parameters, including the pellet materials, algal culture age, and light intensity. Results showed that the Cd(II) removal efficiency was positively related to the algal immobilization efficiency and the algal bioaccumulation capacity. Since higher surface hydrophilicity leads to higher immobilization efficiency, the water-hyacinth leaf biochar pellet (WLBp) was selected as the optimal carrier. A maximum Cd(II) removal efficiency of 92.45% was obtained by the complex of WLBp immobilized with algal cells in stationary growth phase and illuminated with a light intensity of 119 µmol m-2 s-1. Recovery tests on both microalgal cells and the WLBp demonstrated that the algal cells and the biochar pellet can be economically recycled and reused.


Assuntos
Biodegradação Ambiental , Cádmio , Eichhornia , Adsorção , Chlorella , Hyacinthus
8.
Chemosphere ; 195: 632-640, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29289904

RESUMO

Biochar derived from waste water hyacinth was prepared and modified by ZnO nanoparticles for Cr(VI) removal from aqueous solution with the aim of Cr(VI) removal and management of waste biomass. The effect of carbonization temperature (500-800 °C), ZnO content (10-50 wt%) loaded on biochar and contact time (0.17-14 h) on the Cr(VI) removal were investigated. It was found that higher than 95% removal efficiency of Cr(VI) can be achieved with the biochar loaded 30 wt% ZnO. The adsorption kinetics of the sorbent is consistent with the pseudo-second-order kinetic model and adsorption isotherm follows the Langmuir model with maximum adsorption capacity of 43.48 mg g-1 for Cr(VI). Multiple techniques such as XRD, XPS, SEM, EDX and FT-IR were performed to investigate the possible mechanisms involved in the Cr (VI) adsorption. The results show that there is precipitation between chromium ions and Zn oxide. Furthermore, the ZnO nanoparticles acts as photo-catalyst to generate photo-generated electrons to enhance the reduction of Cr(VI) to Cr(III). The as-prepared ZnO/BC possess good recyclability and the removal ratio remained at about 70% in the fifth cycle, which suggests that both contaminants removal and effective management of water hyacinth can be achieved by the approach.


Assuntos
Carvão Vegetal/química , Cromo/química , Descontaminação/métodos , Eichhornia/metabolismo , Nanopartículas/química , Poluentes Químicos da Água/química , Óxido de Zinco/química , Adsorção/fisiologia , Biomassa , Temperatura Alta , Hyacinthus , Concentração de Íons de Hidrogênio , Oxirredução , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias/química
9.
Molecules ; 22(10)2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29053619

RESUMO

Food-derived polysaccharides have advantages over synthetical compounds and have attracted interest globally for decades. In this study, we optimized the cellulase-assisted extraction of polysaccharides from white hyacinth bean (PWBs) with the aid of response surface methodology (RSM). The optimum extraction parameters were a pH of 7.79, a cellulase of 2.73%, and a ratio of water to material of 61.39, producing a high polysaccharide yield (3.32 ± 0.03)%. The scavenging ability of PWBs varied on three radicals (hydroxyl > 2,2-diphenyl-1-picrylhydrazyl (DPPH) > superoxide). Furthermore, PWBs contributed to the proliferation of three probiotic bacteria (Lactobacillus acidophilus LA5, Bifidobacterium bifidum BB01, and Lactobacillus bulgaricus LB6). These investigations of PWBs provide a novel bioresource for the exploitation of antioxidant and probiotic bacterial proliferation.


Assuntos
Celulase/metabolismo , Hyacinthus/química , Polissacarídeos/isolamento & purificação , Bifidobacterium bifidum/efeitos dos fármacos , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/farmacologia , Lactobacillus acidophilus/efeitos dos fármacos , Lactobacillus delbrueckii/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Probióticos
10.
Int J Biol Macromol ; 105(Pt 1): 1349-1356, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28797811

RESUMO

This work describes purification and characterisation of a monocot mannose-specific lectin from Hyacinth bulbs. The purified lectin has a molecular mass of ∼30kDa in reducing as well as in non-reducing SDS-PAGE. In hydrodynamic studies by Dynamic Light Scattering (DLS) showed that purified lectin was monomeric in nature with a molecular size of 2.38±0.03nm. Agglutination activity of purified lectin was confirmed by rabbit erythrocytes and its agglutination activity was inhibited by d-mannose and a glycoprotein (ovalbumin). Glycoprotein nature of purified lectin was confirmed by Periodic Acid Schiff's (PAS) stain. Purified lectin showed moderate pH and thermal stability by retaining hemagglutination activity from pH 6-8 and temperature up to 60°C. It also suppressed the growth of human colon cancer cells (Caco-2) and cervical cancer cells (HeLa) with IC50 values of 127µg/mL and 158µg/mL respectively, after 24-h treatment. Morphological studies of treated cells (Caco-2 and HeLa) with hyacinth lectin by AO/EB dual staining indicated that purified lectin is capable of inducing apoptosis.


Assuntos
Antineoplásicos/farmacologia , Hyacinthus/química , Lectinas de Plantas/farmacologia , Caules de Planta/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Células HeLa , Hemaglutinação/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Peso Molecular , Lectinas de Plantas/química , Lectinas de Plantas/isolamento & purificação , Temperatura
11.
Bioresour Technol ; 241: 908-914, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28629107

RESUMO

For the purpose of safe disposal of biomass contaminated by biosorption of heavy metals, phosphate-assisted pyrolysis of water hyacinth biomass contaminated by lead (Pb) was tried to reduce the bioavailability and leaching potential of Pb, using direct pyrolysis without additive as a control method. Direct pyrolysis of the contaminated biomass at low temperatures (300 and 400°C) could reduce the bioavailability of Pb, but the leaching potential of Pb was increased with the rising pyrolysis temperature. While phosphate-assisted pyrolysis significantly enhanced the recovery and stability of Pb in the char. Specifically, the percentages of bioavailable Pb and leachable Pb in the chars obtained by phosphate-assisted pyrolysis at low temperatures were reduced to less than 5% and 7%, respectively. The sequential extraction test indicated the transformation of Pb into more stable fractions after phosphate-assisted pyrolysis, which was related to the formation of Pb phosphate minerals including pyromorphite and lead-substituted hydroxyapatite.


Assuntos
Eichhornia , Chumbo , Poluentes do Solo , Disponibilidade Biológica , Biomassa , Hyacinthus , Fosfatos , Eliminação de Resíduos Líquidos
12.
Plant Reprod ; 29(3): 251-63, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27422435

RESUMO

During the sexual reproduction of flowering plants, epigenetic control of gene expression and genome integrity by DNA methylation and histone modifications plays an important role in male gametogenesis. In this study, we compared the chromatin modification patterns of the generative, sperm cells and vegetative nuclei during Hyacinthus orientalis male gametophyte development. Changes in the spatial and temporal distribution of 5-methylcytosine, acetylated histone H4 and histone deacetylase indicated potential differences in the specific epigenetic state of all analysed cells, in both the mature cellular pollen grains and the in vitro growing pollen tubes. Interestingly, we observed unique localization of chromatin modifications in the area of the generative and the vegetative nuclei located near each other in the male germ unit, indicating the precise mechanisms of gene expression regulation in this region. We discuss the differences in the patterns of the epigenetic marks along with our previous reports of nuclear metabolism and changes in chromatin organization and activity in hyacinth male gametophyte cells. We also propose that this epigenetic status of the analysed nuclei is related to the different acquired fates and biological functions of these cells.


Assuntos
Cromatina/genética , Epigênese Genética , Hyacinthus/genética , 5-Metilcitosina , Núcleo Celular/genética , Metilação de DNA , Células Germinativas Vegetais , Código das Histonas , Histona Desacetilases/genética , Hyacinthus/crescimento & desenvolvimento , Especificidade de Órgãos , Proteínas de Plantas/genética , Tubo Polínico/genética , Tubo Polínico/crescimento & desenvolvimento , Polinização , Reprodução
13.
Sci Rep ; 6: 20424, 2016 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-26846590

RESUMO

Floating macrophytes, including water hyacinth (Eichhornia crassipes), are dominant invasive organisms in tropical aquatic systems, and they may play an important role in modifying the gas exchange between water and the atmosphere. However, these systems are underrepresented in global datasets of greenhouse gas (GHG) emissions. This study investigated the carbon (C) turnover and GHG emissions from a small (0.6 km(2)) water-harvesting lake in South India and analysed the effect of floating macrophytes on these emissions. We measured carbon dioxide (CO2) and methane (CH4) emissions with gas chambers in the field as well as water C mineralization rates and physicochemical variables in both the open water and in water within stands of water hyacinths. The CO2 and CH4 emissions from areas covered by water hyacinths were reduced by 57% compared with that of open water. However, the C mineralization rates were not significantly different in the water between the two areas. We conclude that the increased invasion of water hyacinths and other floating macrophytes has the potential to change GHG emissions, a process that might be relevant in regional C budgets.


Assuntos
Gases/metabolismo , Hyacinthus/metabolismo , Lagos/análise , Carbono/metabolismo , Dióxido de Carbono/análise , Monitoramento Ambiental , Efeito Estufa , Metano/análise , Oxigênio/análise
15.
Genet Mol Res ; 14(3): 10863-76, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26400314

RESUMO

Karyotype analysis in plants helps to reveal the affinity relationships of species and their genetic evolution. The current study aimed to observe chromosome karyotypes and structures of Hyacinthus orientalis. Twenty hyacinth cultivars were introduced from Holland, and their water-cultivated root tips were used as experimental samples. A solution of colchicine (0.02%) and 8-hydroxyquinoline (0.02 M) was used as a 20-h pre-treatment. Subsequently, Carnot I was used for fixation and 45% acetic acid was used for dissociation. The squash method was selected to prepare chromosome spreads for microscopic observation. The basic chromosome number of the hyacinth cultivar was 8, and the number of chromosomes in the diploid, triploid, tetraploid, and aneuploid cultivars was 16, 23, 24, 31, and 32, respectively. The L-type chromosome was predominant in the chromosomal composition. The hyacinth satellite was located on the short arm in numbers equivalent to the ploidy. This satellite is located on the middle-sized chromosome in the fourth group of chromosomes, demonstrating that Hyacinthus has a more primitive evolution than Lilium and Polygonatum. Among 20 hyacinth cultivars, 'Fondant' had the highest level of evolution and a maximum asymmetric coefficient of 61.69%. Moreover, the ratio between the shortest and longest chromosomes in this cultivar was 4.40, and its karyotype was type 2C. This study may elucidate long-term homonym and synonym phenomena. It may also provide a method of cytological identification as well as direct proof of the high outcross compatibility between hyacinth cultivars.


Assuntos
Hyacinthus/genética , Aberrações Cromossômicas , Cromossomos de Plantas , Evolução Molecular , Cariótipo , Raízes de Plantas/genética
16.
Plant Cell Rep ; 34(12): 2201-15, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26354004

RESUMO

KEY MESSAGE: Calreticulin expression is upregulated during sexual reproduction of Hyacinthus orientalis, and the protein is localized both in the cytoplasm and a highly specialized cell wall within the female gametophyte. Several evidences indicate calreticulin (CRT) as an important calcium (Ca(2+))-binding protein that is involved in the generative reproduction of higher plants, including both pre-fertilization and post-fertilization events. Because CRT is able to bind and sequester exchangeable Ca(2+), it can serve as a mobile intracellular store of easily releasable Ca(2+) and control its local cytosolic concentrations in the embryo sac. This phenomenon seems to be essential during the late progamic phase, gamete fusion, and early embryogenesis. In this report, we demonstrate the differential expression of CRT within Hyacinthus female gametophyte cells before and during anthesis, during the late progamic phase when the pollen tube enters the embryo sac, and at the moment of fertilization and zygote/early endosperm activation. CRT mRNA and the protein localize mainly to the endoplasmic reticulum (ER) and Golgi compartments of the cells, which are involved in sexual reproduction events, such as those in sister synergids, the egg cell, the central cell, zygote and the developing endosperm. Additionally, immunogold research demonstrates selective CRT distribution in the filiform apparatus (FA), a highly specific component of the synergid cell wall. In the light of our previous data showing the total transcriptional activity of the Hyacinthus female gametophyte and the results presented here, we discuss the possible functions of CRT with respect to the critical role of Ca(2+) homeostasis during key events of sexual plant reproduction. Moreover, we propose that the elevated expression of CRT within the female gametophyte is a universal phenomenon in the cells involved in double fertilization in higher plants.


Assuntos
Cálcio/metabolismo , Calreticulina/metabolismo , Regulação da Expressão Gênica de Plantas , Hyacinthus/fisiologia , Calreticulina/genética , Parede Celular/metabolismo , Retículo Endoplasmático/metabolismo , Endosperma/citologia , Endosperma/genética , Endosperma/fisiologia , Fertilização , Células Germinativas Vegetais/citologia , Células Germinativas Vegetais/fisiologia , Homeostase , Hyacinthus/citologia , Hyacinthus/genética , Tubo Polínico/citologia , Tubo Polínico/genética , Tubo Polínico/fisiologia , Polinização , Reprodução , Ativação Transcricional
17.
Biomed Res Int ; 2015: 128256, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26229953

RESUMO

The concentrations of 18 different elements (K, Ca, Fe, Cl, P, Zn, S, Mn, Ti, Cr, Rb, Co, Br, Sr, Ru, Si, Ni, and Cu) were analyzed in five selected vegetables through Proton Induced X-ray Emission (PIXE) technique. The objective of this study was to provide updated information on concentrations of elements in vegetables available in the local markets at Savar subdistrict in Bangladesh. These elements were found in varying concentrations in the studied vegetables. The results also indicated that P, Cl, K, Ca, Mn, Fe, and Zn were found in all vegetables. Overall, K and Ca exhibited the highest concentrations. Cu and Ni exhibited the lowest concentrations in vegetables. The necessity of these elements was also evaluated, based on the established limits of regulatory standards. The findings of this study suggest that the consumption of these vegetables is not completely free of health risks.


Assuntos
Brassica/química , Elementos , Hyacinthus/química , Alface/química , Espectrometria por Raios X/métodos , Spinacia oleracea/química , Verduras/química , Bangladesh
18.
Bioresour Technol ; 193: 103-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26119051

RESUMO

In this study, bioethanol production from NaOH/H2O2-pretreated water hyacinth was investigated. Pretreatment of water hyacinth with 1.5% (v/v) H2O2 and 3% (w/v) NaOH at 25 °C increased the production of reducing sugars (223.53 mg/g dry) and decreased the cellulose crystallinity (12.18%), compared with 48.67 mg/g dry and 22.80% in the untreated sample, respectively. The newly isolated Kluyveromyces marxianu K213 showed greater ethanol production from glucose (0.43 g/g glucose) at 45 °C than did the control Saccharomyces cerevisiae angel yeast. The maximum ethanol concentration (7.34 g/L) achieved with K. marxianu K213 by simultaneous saccharification and fermentation (SSF) from pretreated water hyacinth at 42 °C was 1.78-fold greater than that produced by angel yeast S. cerevisiae at 30 °C. The present work demonstrates that bioethanol production achieved via SSF of NaOH/H2O2-pretreated water hyacinth with K. marxianu K213 is a promising strategy to utilize water hyacinth biomass.


Assuntos
Etanol/metabolismo , Fermentação/fisiologia , Hyacinthus/metabolismo , Peróxido de Hidrogênio/metabolismo , Kluyveromyces/metabolismo , Hidróxido de Sódio/metabolismo , Biocombustíveis/microbiologia , Biomassa , Reatores Biológicos/microbiologia , Celulase/metabolismo , Celulose/metabolismo , Saccharomyces cerevisiae/metabolismo
19.
Science ; 348(6233): 431-4, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25908819

RESUMO

The abundances of molecules containing more than one rare isotope have been applied broadly to determine formation temperatures of natural materials. These applications of "clumped" isotopes rely on the assumption that isotope-exchange equilibrium is reached, or at least approached, during the formation of those materials. In a closed-system terrarium experiment, we demonstrate that biological oxygen (O2) cycling drives the clumped-isotope composition of O2 away from isotopic equilibrium. Our model of the system suggests that unique biological signatures are present in clumped isotopes of O2­and not formation temperatures. Photosynthetic O2 is depleted in (18)O(18)O and (17)O(18)O relative to a stochastic distribution of isotopes, unlike at equilibrium, where heavy-isotope pairs are enriched. Similar signatures may be widespread in nature, offering new tracers of biological and geochemical cycling.


Assuntos
Oxigênio/química , Fotossíntese , Hyacinthus/química , Hyacinthus/metabolismo , Oxigênio/metabolismo , Isótopos de Oxigênio/análise , Isótopos de Oxigênio/química , Complexo de Proteína do Fotossistema II/química , Processos Estocásticos , Temperatura , Água/química
20.
Anal Chim Acta ; 867: 67-73, 2015 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-25813029

RESUMO

In this work, a humidity independent mass spectrometric method was developed for rapid analysis of gas phase chemicals. This method is based upon ambient proton transfer reaction between gas phase chemicals and charged water droplets, in a reaction chamber with nearly saturate humidity under atmospheric pressure. The humidity independent nature enables direct and rapid analysis of raw gas phase samples, avoiding time- and sample-consuming sample pretreatments in conventional mass spectrometry methods to control sample humidity. Acetone, benzene, toluene, ethylbenzene and meta-xylene were used to evaluate the analytical performance of present method. The limits of detection for benzene, toluene, ethylbenzene and meta-xylene are in the range of ∼0.1 to ∼0.3 ppbV; that of benzene is well below the present European Union permissible exposure limit for benzene vapor (5 µg m(-3), ∼1.44 ppbV), with linear ranges of approximately two orders of magnitude. The majority of the homemade device contains a stainless steel tube as reaction chamber and an ultrasonic humidifier as the source of charged water droplets, which makes this cheap device easy to assemble and facile to operate. In addition, potential application of this method was illustrated by the real time identification of raw gas phase chemicals released from plants at different physiological stages.


Assuntos
Gases/química , Umidade , Espectrometria de Massas/métodos , Compostos Orgânicos/análise , Compostos Orgânicos/química , Prótons , Flores/química , Hyacinthus/química , Limite de Detecção , Sonicação , Água/química
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