RESUMO
A regular tetrahedron model was established to pierce the fractionation of dissolved organic matter (DOM) among quaternary components by using high-resolution mass spectrometry. The model can stereoscopically visualize molecular formulas of DOM to show the preference to each component according to the position in a regular tetrahedron. A classification method was subsequently developed to divide molecular formulas into 15 categories related to fractionation ratios, the relative change of which was demonstrated to be convergent with the uncertainty of mass peak area. The practicality of the regular tetrahedron model was verified by seven kinds of sludge from waste leachate treatment and sewage wastewater treatment plants by using stratification of extracellular polymeric substances coupled with Orbitrap MS as an example, presenting the DOM chemodiversity in stratified sludge flocs. Sensitivity analysis proved that classification results were relatively stable with the perturbation of four model parameters. Multinomial logistic regression analysis could further help identify the effect of molecular properties on the fractionation of DOM based on the classification results of the regular tetrahedron model. This model offers a methodology for the assessment of specificity of sequential extraction on DOM from solid or semisolid components and simplifies the complex mathematical expression of fractionation coefficients for quaternary components.
Assuntos
Espectrometria de Massas , Esgotos , Esgotos/química , Compostos Orgânicos/química , Fracionamento Químico , Modelos Teóricos , Águas Residuárias/químicaRESUMO
Paper sludge biomass represents an underutilized feedstock rich in pulped and processed cellulose which is currently a waste stream with significant disposal cost to industry for landfilling services. Effective fractionation of the cellulose from paper sludge presents an opportunity to yield cellulose as feedstock for value-added processes. A novel approach to cellulose fractionation is the sidehill screening system, herein studied at the pilot-plant scale. Composition analysis determined ash removal and carbohydrate retention of both sidehill and high-performance benchtop screening systems. Sidehill screening resulted in greater carbohydrates retention relative to benchtop screening (90% vs 66%) and similar ash removal (95% vs 98%). Techno-economic analysis for production of sugar syrup yielded a minimum selling price of $331/metric ton of sugar syrup including disposal savings, significantly less than a commercial sugar syrup without fractionation. Sensitivity analysis showed that screening conditions played a significant role in economic feasibility for cellulosic yield and downstream processes.
Assuntos
Biomassa , Celulose , Papel , Esgotos , Projetos Piloto , Celulose/química , Fracionamento QuímicoRESUMO
This study investigates the distribution of rare earth elements (REEs) within the Beijing water system, specifically examining the Yongding, Chaobai, Beiyun, Jiyun, and Daqing rivers. Results indicate that the Beiyun River exhibits the highest REE concentrations, ranging from 35.95 to 59.78 µg/mL, while the Daqing River shows the lowest concentrations, ranging from 15.79 to 17.48 µg/mL. LREEs (La to Nd) predominate with a total concentration of 23.501 µg/mL, leading to a notable LREE/HREE ratio of 7.901. Positive Ce anomalies (0.70-1.11) and strong positive Eu anomalies (1.38-2.49) were observed. The study suggests that the Beijing water system's REEs may originate from geological and anthropogenic sources, such as mining and industrial activities in neighboring regions, including Inner Mongolia. These findings underscore the importance of ongoing monitoring and effective water management strategies to address REE-related environmental concerns.
Assuntos
Monitoramento Ambiental , Metais Terras Raras , Rios , Poluentes Químicos da Água , Metais Terras Raras/análise , Monitoramento Ambiental/métodos , Rios/química , Poluentes Químicos da Água/análise , Pequim , China , Fracionamento QuímicoRESUMO
The closure or relocation of many industrial enterprises has resulted in a significant number of abandoned polluted sites enriched in heavy metals to various degrees, causing a slew of environmental problems. Therefore, it is essential to conduct research on heavy metal contamination in the soil of industrial abandoned sites. In this study, soils at different depths were collected in a smelting site located in Hunan Province, China, to understand the Cr distribution, speciation and possible risks. The results revealed that the high-content Cr and Cr(VI) contamination centers were mainly concentrated near S1 (Sample site 1) and S5. The longitudinal migration law of chromium was relatively complex, not showing a simply uniform trend of decreasing gradually with depth but presenting a certain volatility. The vertical distribution characteristics of chromium and Cr(VI) pollution suggest the need for attention to the pollution from chromium slag in groundwater and deep soil layers. The results of different speciation of Cr extracted by the modified European Community Bureau of Reference (BCR) method showed that Cr existed primarily in the residual state (F4), with a relatively low content in the weak acid extraction state (F1). The correlation analysis indicated that Cr was affected by total Cr, pH, organic matter and total carbon during the longitudinal migration process. The RSP results revealed that the smelting site as a whole had a moderate level of pollution. Soil at depths of 2-5 m was more polluted than other soil layers. Consequently, it is necessary to treat the site soil as a whole, especially the subsoil layer (2-5 m). Health risk assessment demonstrated that the soil chromium pollution was hazardous to both adults and children, and the probability of carcinogenic and non-carcinogenic risk was relatively high in the latter group. As a result, children should be a group of special concern regarding the assessment and remediation of soil contaminated with Cr. This study can provide some insight into the contamination characteristics, ecological and health risks of chromium in contaminated soils and offer a scientific basis for the prevention and control of chromium pollution at abandoned smelting sites.
Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Criança , Humanos , Solo/química , Poluentes do Solo/análise , Cromo/toxicidade , Cromo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , China , Medição de Risco , Fracionamento Químico , Monitoramento AmbientalRESUMO
BACKGROUND: Radiation therapy is used to treat head and neck cancer (HNC) patients. Proton beam therapy (PBT) is one of the newer treatment options. This systematic review will describe the cost and cost-effectiveness of PBT compared with other first-line treatment options based on available literature and provide a better understanding of its usage in HNC in the future. METHODS: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Systematic searches were conducted in PUBMED, EMBASE and SCOPUS till February 2022. Original pharmacoeconomic articles written in English that considered PBT for HNC were included; the title, abstract and full text of the search items were screened. The included studies were critically appraised using the Drummond Checklist followed by data extraction. RESULTS: Eight of the ten included studies were of good quality; most were cost-effectiveness or cost comparison studies and used the Markov model and lifetime horizon. The dominant comparator was intensity-modulated radiotherapy. The willingness to pay threshold ranged from $30,828 to $150,000 per QALY. The incremental cost-effectiveness ratio (ICER) was between $4,436.1 and $695,000 per QALY. In HNC patients with human papillomavirus infection, the ICER was lower ($288,000/QALY) from the payer's perspective, but much higher ($390,000/QALY) from the societal perspective. CONCLUSION: Our systematic review showed that appropriate patient selection can make PBT cost-effective. HPV-associated tumors can be cost-effectively treated with PBT. From the payer's perspective, PBT is a cost-effective treatment option. In younger patients, PBT can result in lesser incidence of adverse effects, and hence, can reduce the subsequent need for long-term supportive care. Lower fractionation schedules can also make PBT a cost-effective treatment.
Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Terapia com Prótons , Humanos , Estresse Financeiro , Neoplasias de Cabeça e Pescoço/radioterapia , Fracionamento Químico , Fracionamento da Dose de RadiaçãoRESUMO
Environmental impact assessment of glucose production from paddy milling waste, known as empty and partially filled paddy grain (EPFG) in Malaysia, was performed using life cycle assessment (LCA). Three scenarios were conducted based on system expansion of the process. The LCA was conducted using ReCiPe methodology at midpoint and endpoint levels. The results indicate that enzymatic hydrolysis phase is the hotspot in the conversion system due to enzyme production. In addition, the agriculture phase also contributed to negative impacts, especially towards climate change. An improved environmental load was observed in scenario 2 when all EPFG fractionation was utilised to replace fossil-based electricity. Sensitivity analysis showed an increase in glucose yield leads to reduced environmental impact. Thus, the LCA study suggests that the conversion process of EPFG could further benefit and improve the paddy industry waste management with low impact contribution to the environment compared to other feedstock used for glucose production.
Assuntos
Oryza , Agricultura , Fracionamento Químico , Mudança Climática , Grão Comestível , GlucoseRESUMO
The identification of highly toxic metals like Cd, Ni, Pb, Cr, Co or Cu in ambient particulate matter (PM) has garnered a lot of interest recently. Exposure to toxic metals, including carcinogenic ones, at levels above recommended limits, can significantly affect human health. Prolonged exposure to even trace amounts of toxic or essential metals can also have negative health impacts. In order to assess significant risks, it is crucial to govern the concentrations of bioavailable/bio-accessible metals that are available in PM. Estimating the total metal concentrations in PM is only an approximation of metal toxicity. This review provides an overview of various procedures for extracting soluble toxic metals from PM and the importance of chemical fractionation in risk assessment. It is observed that the environmental risk indices such as bioavailability index (BI), contamination factor (CF) and risk assessment code (RAC) are specifically influenced by the concentration of these metals in a particular fraction. Additionally, there is compelling evidence that health risks assessed using total metal concentrations may be overestimated, therefore, the metal toxicity assessment is more accurate and more sensitive to the concentration of the bioavailable/bio-accessible fraction than the total metal concentrations. Hence, chemical fractionation of toxic metals can serve as an effective tool for developing environmental protection laws and improving air quality monitoring programs for public health.
Assuntos
Fracionamento Químico , Monitoramento Ambiental , Humanos , Intoxicação por Metais Pesados , Disponibilidade Biológica , Medição de RiscoRESUMO
A solid phase chemical fractionation (SPCF) of the Mn in hot infusions prepared from commercial samples of roasted (RM) and green mate (GM) using a chelating resin Chelex 100 (NH4+ form) was performed to assess the relative lability of this essential trace element (ETE). In addition, total Mn contents in the RM and GM samples and their infusions were determined by flame atomic absorption spectrometry. Total polyphenol (TP) contents and the presence of soluble melanoidins (SM) were correlated with the Mn solubility in the RM and GM infusions. From the SPCF study, it was possible to observe that the soluble Mn forms in the mate infusions were essentially associated with relatively noninert chemical species (98.4-99.7%), suggesting that they may be potentially bioavailable. In addition, the soluble Mn contents in the GM infusions were 20.5% higher than those found in the RM. Mn solubility in the (RM) infusions was highly and directly correlated (r = 0.99) with the soluble TP, while in the GM infusions, it was high and inversely correlated with soluble TP (r = -0.87). On the other hand, Mn solubility in the RM and GM infusions was weakly correlated with the SM. It should be stressed that GM infusions can contribute with 57 and 44% more than the RM infusions to the recommended adequate intake of Mn established for females and males, respectively. Moreover, this work is the first to evaluate and compare the relative lability of Mn and its solubility in the RM and GM infusions.
Assuntos
Manganês , Oligoelementos , Manganês/análise , Solubilidade , Oligoelementos/análise , Fracionamento Químico , Polifenóis/análiseRESUMO
Bayesian stable isotope mixing models are widely used in geochemical and ecological studies for partitioning sources that contribute to various mixtures. However, none of the existing tools allows accounting for the influence of processes other than mixing, especially stable isotope fractionation. Bridging this gap, new software for the stable isotope Fractionation And Mixing Evaluation (FRAME) has been developed with a user-friendly graphical interface (malewick.github.io/frame). This calculation tool allows simultaneous sources partitioning and fractionation progress determination based on the stable isotope composition of sources/substrates and mixture/products. The mathematical algorithm applies the Markov-Chain Monte Carlo model to estimate the contribution of individual sources and processes, as well as the probability distributions of the calculated results. The performance of FRAME was comprehensively tested and practical applications of this modelling tool are presented with simple theoretical examples and stable isotope case studies for nitrates, nitrites, water and nitrous oxide. The open mathematical design, featuring custom distributions of source isotope signatures, allows for the implementation of additional processes that alternate the characteristics of the final mixture and its application for various range of studies.
Assuntos
Fracionamento Químico , Isótopos , Teorema de Bayes , Fracionamento da Dose de Radiação , Método de Monte CarloRESUMO
Biodegradation of lower chlorinated benzenes (tri-, di- and monochlorobenzene) was assessed at a coastal aquifer contaminated with multiple chlorinated aromatic hydrocarbons. Field-derived microcosms, established with groundwater from the source zone and amended with a mixture of lower chlorinated benzenes, evidenced biodegradation of monochlorobenzene (MCB) and 1,4-dichlorobenzene (1,4-DCB) in aerobic microcosms, whereas the addition of lactate in anaerobic microcosms did not enhance anaerobic reductive dechlorination. Aerobic microcosms established with groundwater from the plume consumed several doses of MCB and concomitantly degraded the three isomers of dichlorobenzene with no observable inhibitory effect. In the light of these results, we assessed the applicability of compound stable isotope analysis to monitor a potential aerobic remediation treatment of MCB and 1,4-DCB in this site. The carbon isotopic fractionation factors (ε) obtained from field-derived microcosms were -0.7 ± 0.1 and -1.0 ± 0.2 for MCB and 1,4-DCB, respectively. For 1,4-DCB, the carbon isotope fractionation during aerobic biodegradation was reported for the first time. The weak carbon isotope fractionation values for the aerobic pathway would only allow tracing of in situ degradation in aquifer parts with high extent of biodegradation. However, based on the carbon isotope effects measured in this and previous studies, relatively high carbon isotope shifts (i.e., ∆δ13C > 4.0 ) of MCB or 1,4-DCB in contaminated groundwater would suggest that their biodegradation is controlled by anaerobic reductive dechlorination.
Assuntos
Água Subterrânea , Poluentes Químicos da Água , Biodegradação Ambiental , Isótopos de Carbono , Fracionamento Químico , Poluentes Químicos da Água/análiseRESUMO
Coal ash has emerged as an important alternative source for rare earth elements (REEs). The enrichment and occurrence form of REEs among coal combustion products are of great significance for both technical design and economic evaluation of recovering REEs from the coal ash. Here, the enrichment and occurrence form of REEs in the ash were investigated. Compared with ashes from muffle furnace, coal fly ash (CFA) from power plants involved higher enrichment ratio of REEs, which was explained by the fractionation of coal ashes to concentrate REEs in finer CFA, higher combustion temperature to vaporize more volatile elements, and longer residence time of fly ash to absorb REEs in the gas. In addition, CFA samples were analyzed by sequence chemical extraction procedure (SCEP) and scanning electron microscope with an energy dispersive spectrometer (SEM-EDX), which revealed the important role of aluminum in the occurrence form of REEs compared with Si in aluminosilicates of CFA. This conclusion was further confirmed by thermodynamic equilibrium calculation, which also agreed qualitatively with the observation that REEs mainly existed in the solid phase. Both experimental and computational results of this work provided insights to understand the distribution of REEs in CFA and optimize their extraction processes.
Assuntos
Carvão Mineral , Metais Terras Raras , Fracionamento Químico , Carvão Mineral/análise , Cinza de Carvão/análise , Centrais ElétricasRESUMO
The primary focus of this research was the chemical fractionation of potentially toxic elements (PTEs) and their presence in several industrialised cities in Serbia. Furthermore, their origin, contamination levels, and environmental and human health risks were assessed. The results indicated that the examined soils were characterised by slightly higher Cu, Ni, Pb, and Zn levels than those set by European and national regulations. These elevated Cu, Pb, and Zn concentrations were caused by intensive traffic and proximity to industry, whereas the higher Ni levels were a result of the specific geological substrate of the soil in the study area. The environmental risk was found to be low and there was no enrichment/contamination of the soil with these elements, except in the case of Pb, for which moderate to significant enrichment was found. Lead also poses a potential non-carcinogenic risk to children through ingestion and requires special attention due to the fact that a significant proportion of this element was present in the tested soil samples in a potentially available form. Analysis of the health risks showed that children are more at risk than adults from contaminants and that ingestion is the riskiest exposure route. The carcinogenic risk was within the acceptable limits.
Assuntos
Metais Pesados , Poluentes do Solo , Adulto , Fracionamento Químico , Criança , Cidades , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Sérvia , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidadeRESUMO
Microwave hydrothermal treatment (MHT), a novel advanced technology, was proposed for the fractionation of Paulownia wood (PW) at temperatures ranging 200-230 °C and residence times of 0-50 min, corresponding to severities of 2.93-4.70. This procedure allowed 80% of xylan recovery as xylooligosaccharides and an average of 95% cellulose recovery in the pretreated PW biomass, showing the selectivity of the treatment, that was also compared to conduction-convection heating autohydrolysis. Finally, a kinetic model was proposed for the prediction of PW fractionation using MHT, with the ultimate goal of being applied to a wide range of feedstocks and minimizing the number of parameters used. For that, two strategies were approached, allowing the reduction of 80 to 34 parameters, without significant influence in the kinetic fitting. To the best of our knowledge, this is the first kinetic modelization of MHT of PW, taking into account all the lignocellulosic fractions.
Assuntos
Micro-Ondas , Madeira , Biomassa , Celulose , Fracionamento Químico , HidróliseRESUMO
In this work, extraction of flavonoids from peanut shells has been studied in the presence of ultrasound and the results are compared with Soxhlet and heat reflux extraction for establishing the process intensification benefits. The process optimization for understanding the effects of operating parameters, such as ethanol concentration, particle size, solvent to solid ratio, extraction temperature, ultrasonic power and ultrasonic frequency, on the extraction of flavonoids has been investigated in details. The highest extraction yield (9.263 mg/g) of flavonoids was achieved in 80 min at optimum operating parameters of particle size of 0.285 mm, solvent to solid ratio of 40 ml/g, extraction temperature of 55 °C, ultrasonic power of 120 W and ultrasonic frequency of 45 kHz with 70% ethanol as the solvent. Two kinetic models (i.e. phenomenological model and Peleg's model) have been introduced to describe the extraction kinetic of flavonoids by fitting experimental data and predict kinetic parameters. Good performance with slight loss of goodness of fit of two models was found by comparing their coefficient of determination (R2), root mean square error (RMSE) and/or mean percentage error (MPE) values. This work would provide the reduction of degradation and the economic evaluation for the extraction processes of flavonoids from peanut shells, as well as give a better explanation for the mechanism of ultrasound.
Assuntos
Arachis/química , Fracionamento Químico/métodos , Flavonoides/isolamento & purificação , Ondas Ultrassônicas , CinéticaRESUMO
The present work was focused on the investigation of lignin isolation from saw industry biomass (sawdust (SD)) using alkali solution, and to perform economic analysis for 2000 kg/batch hypothetical plant using techno-economic analysis. The isolated lignin was fractionated using organic solvent to obtain purified lignin. FTIR and 1H NMR analysis were performed to examine the structural characteristics of lignin. Lignin nanoparticles (LN) showed higher total phenolic content (TPC) (244.1 ± 2 µg of GAE per mg) and antioxidant activity (63.2 ± 1.7%) compared with crude lignin (CL), ethanol fractionated lignin (EL), and acetone fractionated lignin (AL). SuperPro designer was exposed to design and simulated 2000 kg/batch of sawdust fractionation process. The techno-economic analysis estimated that the lignin production cost is about $ 487,000 per year, and the annual revenue could be $ 1,850,000 per year. The techno-economic analysis and sensitivity analysis could be useful for the industrial level sawdust fractionation process.
Assuntos
Álcalis , Lignina , Fracionamento Químico , Análise Custo-Benefício , Resíduos IndustriaisRESUMO
Isolating high quality RNA is a limiting factor in molecular analysis, since it is the base for transcriptional studies. The RNA extraction method can directly affect the RNA quality and quantity, as well as, its overall cost. The industrial importance of the yeast genus Candida in several sectors comes from their capacity to produce Lipases. These enzymes are one of the main metabolites produced by some Candida species, and it has been shown that Candida yeast can biodegrade petroleum hydrocarbons and diesel oil from biosurfactants that they can produce, a feature that turns these organisms into potential combatants for bioremediation techniques. Thus, this study aimed to determine an efficient method for isolating high quality RNA from Candida viswanathii biomass. To achieve this aim, three different RNA extraction methods, TRIzol, Hot Acid Phenol, and CTAB (Cetyltrimethylammonium Bromide), were tested. The three tested methods allowed the isolation of high-quality RNA from C. viswanathii biomass and yielded suitable RNA quantity for carrying out RT-qPCR studies. In addition, all methods displayed high sensitivity for the expression analysis of the CvGPH1 gene through RT-qPCR, with TRIzol and CTAB showing the best results and the CTAB method displaying the best cost-benefit ratio (US$0.35/sample).
Assuntos
Candida/genética , Fracionamento Químico/métodos , RNA Fúngico/isolamento & purificação , Candida/crescimento & desenvolvimento , Candida/isolamento & purificação , Cetrimônio/química , Fracionamento Químico/instrumentação , Fenol/química , Reação em Cadeia da Polimerase , RNA Fúngico/genéticaRESUMO
In this chapter, we describe a rapid workflow for the shotgun global phosphoproteomics analysis. The strategy is based on the use of accelerated in-solution trypsin digestion under an ultrasonic field by high-intensity focused ultrasound (HIFU) coupled to titanium dioxide (TiO2) selective phosphopeptide enrichment, fractionation by strong cation exchange chromatography (SCX), and analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) in a high-resolution mass spectrometer (LTQ-Orbitrap XL). The strategy was optimized for the global phosphoproteome analysis of Jurkat T-cells. Using this accelerated workflow, HIFU-TiO2-SCX-LC-MS/MS, 15,367 phosphorylation sites from 13,029 different phosphopeptides belonging to 3,163 different phosphoproteins can be efficiently identified in less than 15 h.
Assuntos
Fosfopeptídeos/análise , Fosfoproteínas/análise , Proteômica/métodos , Fracionamento Químico/métodos , Cromatografia por Troca Iônica/economia , Cromatografia por Troca Iônica/métodos , Humanos , Células Jurkat , Fosfopeptídeos/isolamento & purificação , Fosfoproteínas/isolamento & purificação , Fosforilação , Proteoma/análise , Proteoma/isolamento & purificação , Proteômica/economia , Espectrometria de Massas em Tandem/economia , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo , Titânio/química , Fluxo de TrabalhoRESUMO
BACKGROUND: Extraction is the foremost step to isolate the natural constituents from a medicinal plant and leads the process of development of herbal formulation from bench to bed. INTRODUCTION: In the field of extraction, the optimization approach helps in achieving better yield and quality where a response of concern is determined or influenced by various variables. This review aimed at congregating the application of different statistical designs (CCD/BBD) to optimize the Ultrasound assisted extraction (UAE) parameters for the recovery of various plant actives belonging to different categories. METHODOLOGY: The literature published during the last decade in the various reputed databases (Web of Science, Pubmed, Scopus) was reviewed and compiled to reveal the role of response surface methodology in optimizing the influential parameters involved in the ultrasound assisted extraction of herbs. CONCLUSION: From the present investigations, it can be concluded that the different variables, such as sonication power, temperature, time, solute to solvent ratio are generally optimized in UAE of herbs. Moreover, it has also been evidenced from the review of published data that the flavonoids/phenolic acids (>50%) leads the race for the extraction of plants using sound waves. It can be said that the statistically designed UAE has a vast prospective in bringing about a green mutiny in the herbal drug industry and the modeling of various parameters shall be able to absolutely build up a complete drug innovation course (bench to bed).
Assuntos
Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Plantas Medicinais/química , Ondas Ultrassônicas , Fracionamento Químico/métodos , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Estudos Prospectivos , SonicaçãoRESUMO
Water-extracted polysaccharides from Russula vinosa Lindblad (WRP) were separated into three fractions (WRP-1, WRP-2 and WRP-3) by gradient ethanol precipitation and gel chromatography. Structural characterization indicated that WRP-1 was a branched ß-(1â3)-glucan and exhibited rigid helical conformation in aqueous solution with Mw of 2,180 kDa and radius of gyration (Rg) of 123.4 nm. The galactoglucan of WRP-2 and WRP-3 were mainly composed of â6)-Galp-(1â and â4)-Glcp-(1â terminated by glucose and mannose, presenting much lower Mw (392 and 93.6 kDa) and Rg (57.6 and 42.6 nm), and more incompact flexible conformation than WRP-1. All fractions showed potential immunostimulatory activity by promoting macrophage proliferation, phagocytosis, as well as the release of nitric oxide and cytokines (TNF-α and IL-1ß). WRP-1 with unique structure and conformation showed the best immunostimulatory effects among them. This study suggests that WRP could be explored as natural immunostimulator used in the food and pharmaceutical industry.
Assuntos
Basidiomycota/química , Galactanos/química , Glucanos/química , Polissacarídeos Bacterianos/química , beta-Glucanas/química , Animais , Técnicas de Cultura de Células , Proliferação de Células , Sobrevivência Celular , Fracionamento Químico , Cromatografia em Gel , Vermelho Congo/química , Citocinas/metabolismo , Indústria Farmacêutica , Etanol , Indústria Alimentícia , Glucose/química , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Manose/química , Camundongos , Fagocitose , Polissacarídeos/química , Células RAW 264.7 , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
Determination of potential mobility of toxic trace metals in sediments under changing redox condition is important in ecological risk assessment. Current methods are limited in risk prediction in such dynamic environment. In this study, we have discussed the general disagreement from widely used methods (sediment quality guideline (SQGs), potential ecological risk index (PERI), risk assessment code (RAC) using BCR fraction information). In addition, the stable isotopic dilution method (IDM) was also modified to quantify metal lability in a microcosm experiment mimicking river bank sediment turning into anaerobic. The isotopically exchangeable Cd, Cu, Pb, and Zn quantified by IDM (%E incub) was used in the RAC to reveal the trend of risk during this process. Strong risks from Cd are suggested by the PERI and RAC as a result of high toxicity and mobility of the element, while SQGs suggests medium risk for Cu, Pb, and Zn in certain samples. The disagreement between the results of RAC assessed by metal lability (%E dry) and by BCR metal fractionation reflects the effect of sediment properties and source of metal contamination. The RAC based on the non-residual fractions is likely to overestimate the potential risk for most metals even there is a significant change in sediment Eh. The RAC assessed by %E incub reveals that the variability in risk in response to the reducing Eh is not consistent. Large fluctuation in %E incub for Cd (28.5%, 49.5%), Pb (27.6%, 18.2%), and Cu (14.4%, 24.7%) can shift the risks to a higher level in certain range of Eh in two sediments. In sediment with lower contents of metal binding phases (e.g. mineral oxides, organic matters), the release of metals can be more significant, thus higher ecological risk in changing redox condition.