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1.
J Equine Vet Sci ; 132: 104975, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38040068

RESUMO

Foals require maternal colostrum in the first hours of life to prevent failure of transfer of passive immunity (FTIP). Innovative storage methods such as lyophilization may enable conservation of colostrum immunoglobulins by a differentiated process of dehydration. The current study aimed to compare the quality of equine colostrum after freezing and after the lyophilization process. Thirty-one pregnant Quarter Horse mares were used. The IgG concentration of frozen and lyophilized colostrum was determined by simple radial immunodiffusion (SRID) and Brix refractometry. The physical-chemical composition (pH, total protein (TP), fat, lactose, salts, total solids (TS), and density) of the samples was evaluated and the lyophilized colostrum reconstitution test was performed. There were no significant differences (P > 0.05) in the variables IgG, fat, lactose, salts, TS, density, and pH between samples measured before and after lyophilization. There was a significant difference (P < 0.05) between the Brix average and the TP of the frozen and lyophilized colostrum samples. Lyophilization resulted in a small reduction (6.55%) in the IgG concentration measured by SRID. A strong positive correlation was observed between colostrum density and IgG concentration by SRID (r = 0.76) and between Brix and IgG concentration by SRID (r = 0.77). In the reconstitution test, the lyophilized colostrum was easily rehydrated in water, with full dilution, and remained stable. Lyophilization could be an alternative for the conservation of mare colostrum, since it is a very efficient process for retaining the physicochemical characteristics of the product, with minimal loss, particularly of IgG.


Assuntos
Colostro , Lactose , Gravidez , Animais , Cavalos , Feminino , Lactose/análise , Sais/análise , Imunoglobulina G/análise , Refratometria/veterinária
2.
Toxicol Ind Health ; 39(10): 583-593, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37530424

RESUMO

Textile effluents, although their composition can vary considerably, typically contain high levels of dissolved salts and exhibit wide variations in pH. Ecotoxicological studies regarding the effects of these parameters, however, have been limited owing to the need for sensitive and easy-to-handle bioindicators that require low amounts of sampling, are cost-effective, time-efficient, and ethically endorsed. This kind of study, additionally, demands robust multi-factorial statistical designs that can accurately characterize the individual and combined relationship between variables. In this research, Response Surface Methodology (RSM) was used to calculate the individual and interaction effects of NaCl concentration and pH value of a Simulated Textile Effluent (STE) on the development rate (DR) of the bioindicators: Bacillus subtilis bacteria and Lactuca sativa lettuce. The results demonstrated that the bioindicators were sensitive to both NaCl and pH factors, where the relative sensitivity relationship was B. subtilis > L. sativa. The quadratic equations generated in the experiments indicated that increased concentrations of 50-250 mg L-1 of NaCl caused a perturbance of 1.40%-34.40% on the DR of B. subtilis and 0.50%-12.30% on L. sativa. The pH factor at values of 3-11 caused an alteration of 27.00%-64.78% on the DR of the B. subtilis and 51.37%-37.37% on the L. sativa. These findings suggest that the selected bioindicators could serve as effective tools to assess the ecotoxicological effects of textile effluents on different ecological systems, and the RSM was an excellent tool to consider the ecotoxicological effects of the parameters and to describe the behavior of the results. In conclusion, the NaCl and pH factors may be responsible for disrupting different ecosystems, causing imbalances in their biodiversity and biomass. Before discharge or reuse, it is suggested to remove salts and neutralize pH from textile effluents and, mostly, develop novel, eco-friendlier textile processing techniques.


Assuntos
Bacillus subtilis , Poluentes Químicos da Água , Cloreto de Sódio/toxicidade , Cloreto de Sódio/análise , Ecossistema , Biomarcadores Ambientais , Sais/análise , Concentração de Íons de Hidrogênio , Têxteis , Indústria Têxtil , Poluentes Químicos da Água/análise , Resíduos Industriais/análise
3.
Braz J Biol ; 84: e271324, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37194757

RESUMO

As a result of intensive anthropogenic impact in the biosphere there is a rapid process of accumulation of heavy metal salts. They have led to the aggravation of problems associated with the pollution of ecosystems and basic food products of plant and animal origin. Environmental pollution by these compounds is caused by their persistence in environmental objects, migration ability, accumulation by plants. This contributes to their accumulation in the human environment. A number of studies have shown that heavy metals have mutagenic, toxic effects and affect the intensity of biochemical processes. Therefore, the presence of heavy metals in the environment is extremely undesirable. Moreover, the ecological state of the environment is directly related to changes in the human internal environment. Deficiency or excess of certain bioelements in soils and drinking water or non-compliance with its stable chemical composition causes the development of dysmicroelementosis. The ecological situation of the Carpathian region is closely related to the state of soils and water resources. In this regard, it is advisable to study and control the level of cadmium compounds in the environment of the region. The study of the effect of cadmium intoxication on the macro- and microelement composition of the brain and myocardium of experimental animals is also worthwhile. Materials and methods. Soils and drinking water of the plain, foothill and mountainous zones of the region, as well as organs and tissues of experimental animals served as the object of research. Cadmium levels in drinking water and myocardial tissues and brain of experimental animals have been measured by atomic absorption spectroscopy. Results and discussion. The study of soils in the Prykarpattia region has revealed an increase in the toxic element cadmium. Its content is 1.1-1.5 times higher than background levels. The analysis of drinking water allowed to establish that a significant number of people living in the plain and foothill zone of the region consume water with a high content of cadmium. The main stages of cadmium intake and accumulation in plants have been analyzed. Significant disorders in the body of experimental animals under conditions of excessive intake of cadmium compounds have been revealed. It was accompanied by the accumulation of cadmium in the myocardium and brain, on the background of redistribution of vital macronutrients calcium and magnesium along with micronutrients copper and zinc. Thus, excessive intake of cadmium salts causes the development of dysmicroelementosis, which is accompanied by a violation of the homeostasis of a living organism. It is suggested to conduct continuous monitoring of the level of toxicants in the ecosystem as an integral component of environmental monitoring.


Assuntos
Água Potável , Metais Pesados , Poluentes do Solo , Animais , Humanos , Cádmio/toxicidade , Ecossistema , Sais/análise , Água Potável/análise , Metais Pesados/análise , Solo/química , Plantas/química , Monitoramento Ambiental , Poluentes do Solo/análise
4.
Food Addit Contam Part B Surveill ; 16(1): 24-31, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36053003

RESUMO

In this study, 18 different samples of unrefined coarse food salt were examined using inductively coupled plasma mass spectrometry and Fourier transform infrared spectroscopy. Additionally, microphotographs were taken to determine the visual distribution of the impurities in the salt samples. None of the salt samples analysed contained arsenic, mercury, tin, and antimony. Cadmium, chromium, nickel, lead, barium, lithium, aluminium, titanium, vanadium, cobalt, cupper, iron, zinc, manganese, magnesium, and calcium were determined in some salt samples. According to the results of FTIR analysis mainly polyamide polymer derivatives were found in Himalaya White, Himalaya, Klodawa, Nakhchivan, Delice, Guérande Flake, Guérande Celtic, Maldon, Havaii Black, Havaii Green, Havaii Red, Maras, and Izmir salts.


Assuntos
Arsênio , Sais , Sais/análise , Cobre , Contaminação de Alimentos/análise , Zinco/análise , Cromo/análise , Cádmio/análise , Magnésio , Arsênio/análise
5.
J Environ Radioact ; 257: 107083, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36516518

RESUMO

Enrichment of heavy isotopes of hydrogen (D, 3H) and oxygen (18О) is observed in water samples collected from open brine storage of Kalush-Golinsky deposit. The brine storage facilities were formed during the operation of the Kalush-Golynsky deposit of potassium salts and after its decommissioning. Enrichment of isotopes is also observed in groundwater samples, collected from wells located along with downstream groundwater from brine storage facilities. The analysis of levels of influence of possible sources of chemical pollution of groundwater (waters of the Dombrovsky quarry, tailings and sludge storage, salt dumps, saline soils) and correlation relationships between isotopes and groundwater mineralization have been determined by statistical processing of geochemical data.


Assuntos
Água Subterrânea , Monitoramento de Radiação , Poluentes Químicos da Água , Sais/análise , Sais/química , Potássio/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água Subterrânea/química , Isótopos de Oxigênio/análise
6.
J Dairy Sci ; 106(1): 117-131, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36357208

RESUMO

Process cheese products (PCP) are dairy foods prepared by blending dairy ingredients (such as natural cheese, protein concentrates, butter, nonfat dry milk, whey powder, and permeate) with nondairy ingredients [such as sodium chloride, water, emulsifying salts (ES), color, and flavors] and then heating the mixture to obtain a homogeneous product with an extended shelf life. The ES, such as sodium citrate and disodium phosphate, are critical for the unique microstructure and functional properties of PCP because they improve the emulsification characteristics of casein by displacing the calcium phosphate complexes that are present in the insoluble calcium-paracaseinate-phosphate network in natural cheese. The objectives of this study were to determine the optimum protein content (3, 6, and 9% protein) in micellar casein concentrate (MCC) to produce acid curd and to manufacture PCP using a combination of acid curd cheese and MCC that would provide the desired improvement in the emulsification capacity of caseins without the use of ES. To produce acid curd, MCC was acidified using lactic acid to get a pH of 4.6. In the experimental formulation, the acid curd was blended with MCC to have a 2:1 ratio of protein from acid curd relative to MCC. The PCP was manufactured by blending all ingredients in a KitchenAid blender (Professional 5 Plus, KitchenAid) to produce a homogeneous paste. A 25-g sample of the paste was cooked in the rapid visco analyzer (RVA) for 3 min at 95°C at 1,000 rpm stirring speed during the first 2 min and 160 rpm for the last min. The cooked PCP was then transferred into molds and refrigerated until further analysis. This trial was repeated 3 times using different batches of acid curd. MCC with 9% protein resulted in acid curd with more adjusted yield. The end apparent viscosity (402.0-483.0 cP), hardness (354.0-384.0 g), melting temperature (48.0-51.0°C), and melting diameter (30.0-31.4 mm) of PCP made from different acid curds were slightly different from the characteristics of typical PCP produced with conventional ingredients and ES (576.6 cP end apparent viscosity, 119.0 g hardness, 59.8°C melting temperature, and 41.2 mm melting diameter) due to the differences in pH of final PCP (5.8 in ES PCP compared with 5.4 in no ES PCP). We concluded that acid curd can be produced from MCC with different protein content. Also, we found that PCP can be made with no ES when the formulation uses a 2:1 ratio of acid curd relative to MCC (on a protein basis).


Assuntos
Queijo , Animais , Queijo/análise , Caseínas/química , Sais/análise , Micelas , Leite/química , Fosfatos/análise , Manipulação de Alimentos/métodos
7.
Environ Sci Pollut Res Int ; 30(8): 19994-20005, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36242671

RESUMO

Microplastics (MPs), together with microfibers, have emerged as a contaminant of concern all around the globe. MPs have been detected in freshwater, seawater, sediment, and aquatic species among others. As suggested by several recent investigations, sea salts, a daily intake item by humans, are also contaminated by MPs. The current article describes MPs' occurrence, distribution, type, and timeline variation in raw sea salts from Cox's Bazar, Bangladesh. MPs have been detected in every collected salt sample, and quantity varied from 28.53 ± 2.43 to 93.53 ± 4.21 particles per kg, which was about 52.48 ± 1.72 to 67.46 ± 3.81 µg/kg of raw salt. Microfibers were MPs' dominant shape category, and the plastic types were mainly polyester or nylon. Other types of MPs were polyethylene (PE), polypropylene (PP), polycarbonate (PC), polyurethane (PU), and polystyrene (PS) in decreasing amounts. The majority of the MPs in the sea salts were in the size range of ˂ 3-1 mm. The total amount of MPs and plastic-type variation due to sampling location (p ˃ 0.05) and because of the time period (p ˃ 0.05) was found insignificant. Acetaldehyde, a volatile toxic substance produced by the degradation of polyester polymer chains, was detected in MPs in the range of 0.37 to 1.72 µg/g by headspace GC-MS analysis. Hence, the sea salts contaminated with MPs pose a public health hazard. Microplastics extraction from sea salts and their characterization.


Assuntos
Microplásticos , Poluentes Químicos da Água , Humanos , Microplásticos/análise , Plásticos/análise , Sais/análise , Bangladesh , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Poliésteres
8.
Molecules ; 27(24)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36558134

RESUMO

Pinus radiata bark is a rich source of polyphenols, which are mainly composed of proanthocyanidins. This study aimed to utilize P. radiata bark as a polyol source for bio-foam production in the future. Polyphenol-rich alkaline extracts (AEs) from P. radiata bark were prepared by mild alkaline treatment and then derivatized with propylene oxide (PO). Hydroxypropylated alkaline extracts (HAEs) with varying molar substitutions (MS 0.4-8.0) were characterized by FT-IR, NMR, GPC, TGA, and DSC. The hydroxyl value and solubility in commercial polyols were also determined. The molecular weights of the acetylated HAEs (Ac-HAEs) were found to be 4000 to 4900 Da. Analyses of FT-IR of HAEs and 1H NMR of Ac-HAEs indicated that the aromatic hydroxyl groups were hydroxypropylated and showed an increase in aliphatic hydroxyl group content. The glass transition temperature (Tg) of AE and HAEs were 58 to 60 °C, showing little difference. The hydroxyl value increased as the hydroxypropylation proceeded. Although salts were produced upon neutralization after hydroxypropylation, HAEs still showed suitable solubility in polyether and polyester polyols; HAEs dissolved well in polyether polyol, PEG#400, and solubility reached about 50% (w/w). This indicated that neutralized HAEs could be directly applied to bio-foam production even without removing salts.


Assuntos
Pinus , Polifenóis , Polifenóis/análise , Pinus/química , Casca de Planta/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sais/análise , Extratos Vegetais/química
9.
Environ Pollut ; 314: 120273, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36170893

RESUMO

Hourly PM2.5 speciation data have been widely used as an input of positive matrix factorization (PMF) model to apportion PM2.5 components to specific source-related factors. However, the influence of constant source profile presumption during the observation period is less investigated. In the current work, hourly concentrations of PM2.5 water-soluble inorganic ions, bulk organic and elemental carbon, and elements were obtained at an urban site in Nanjing, China from 2017 to 2020. PMF analysis based on observation data during specific pollution (firework combustion, sandstorm, and winter haze) and emission-reduction (COVID-19 pandemic) periods was compared with that using the whole 4-year data set (PMFwhole). Due to the lack of data variability, event-based PMF solutions did not separate secondary sulfate and nitrate. But they showed better performance in simulating average concentrations and temporal variations of input species, particularly for primary source markers, than the PMFwhole solution. After removing event data, PMF modeling was conducted for individual months (PMFmonth) and the 4-year period (PMF4-year), respectively. PMFmonth solutions reflected varied source profiles and contributions and reproduced monthly variations of input species better than the PMF4-year solution, but failed to capture seasonal patterns of secondary salts. Additionally, four winter pollution days were selected for hour-by-hour PMF simulations, and three sample sizes (500, 1000, and 2000) were tested using a moving window method. The results showed that using short-term observation data performed better in reflecting immediate changes in primary sources, which will benefit future air quality control when primary PM emissions begin to increase.


Assuntos
Poluentes Atmosféricos , COVID-19 , Humanos , Material Particulado/análise , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Monitoramento Ambiental/métodos , Nitratos/análise , Sais/análise , Pandemias , Estações do Ano , Carbono/análise , China , Água/análise , Sulfatos/análise
10.
Chemosphere ; 308(Pt 2): 136395, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36096307

RESUMO

In aquatic environments, microplastics (MPs) are pervasive which could have a considerable negative impact on the environment, organisms and pose a risk to human health. However, knowledge about the exposure and ecological risk of MPs in the coastal ecosystems of developing countries is limited. In this study, we analyzed salt samples from five commonly consumed processed and unprocessed sea salts of different commercial brands originated from 15 salt pans in Bangladesh to assess the abundance, characteristics and potential risks of MPs. The quantities of MPs in unprocessed salts (average 195 ± 56 item/kg) were higher than those in the processed salts (average 157 ± 34 item/kg). One-way analysis of variance (ANOVA) showed significant (p < 0.05) differences among the average numbers of MPs in both processed and unprocessed salts. MP levels in this study were 2-3 times higher than those reported from some other countries. Fiber-shaped and transparent MPs were dominant in both cases. MPs less than 0.5 mm in size were the most abundant in both unprocessed (58.2%) and processed (62.2%) salts. Fourier-transform infrared spectroscopy (FTIR) analysis confirmed five types of polymers, including polyethylene terephthalate (PET-35%), polypropylene (PP-27.5%), polyethylene (PE-25%), polystyrene (PS-10%), and Nylon (2.5%) in the studied salts. The sea salts were classified as potential hazard index (PHI) levels IV to V, indicating serious MP contamination, whereas potential ecological risk factor (Ei), potential ecological risk index (RI), and pollutant load index (PLI) indicated moderate levels of pollution of MPs. Domestic and municipal wastewater effluents to Bay of Bengal and fishing activities may attributed to presence of MPs in the sea salt. These findings can be used by consumers, salt industries and policy makers to reduce MPs levels during consumption, production and policymaking.


Assuntos
Microplásticos , Poluentes Químicos da Água , Países em Desenvolvimento , Ecossistema , Monitoramento Ambiental , Humanos , Nylons , Plásticos/química , Polietileno/análise , Polietilenotereftalatos , Polímeros , Polipropilenos/análise , Poliestirenos/análise , Medição de Risco , Sais/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise
11.
Environ Sci Process Impacts ; 24(11): 2070-2084, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36044235

RESUMO

High-latitude urban regions provide a unique and complex range of environmental surfaces for uptake of trace pollutant gases, including winter road maintenance materials (e.g., gravel, rock salts, and anti-icer, a saline solution applied to roads during winter). In an effort to reduce the negative environmental and economic impacts of road salts, many municipalities have turned to agro-based anti-icing materials that are rich in organic material. To date, the reactivity of both anti-icer and saline road dust with pollutant gases remain unexplored, which limits our ability to assess the potential impacts of these materials on air quality in high-latitude regions. Here, we used a coated-wall flow tube to investigate the uptake of ozone, an important air pollutant, by road dust collected in Edmonton, Canada. At 25% relative humidity (RH) and 50 ppb ozone, γBET for ozone uptake by this sample is (8.0 ± 0.7) × 10-8 under dark conditions and (2.1 ± 0.1) × 10-7 under illuminated conditions. These values are 2-4× higher than those previously obtained by our group for natural mineral dusts, but are not large enough for suspended road dust to influence local ozone mixing ratios. In a separate set of experiments, we also investigated the uptake of ozone by calcium chloride (i.e., road salt) and commercial anti-icer solution. Although ozone uptake by pure calcium chloride was negligible, ozone uptake by anti-icer was significant, which implies that the reactivity of anti-icer is conferred by its organic content. Importantly, ozone uptake by anti-icer-and, to a lesser extent, road dust doped with anti-icer-leads to the release of inorganic chlorine gas, which we collected using inline reductive trapping and quantified using ion chromatography. To explain these results, we propose a novel pathway for chlorine activation: here, ozone oxidation of the anti-icer organic fraction (in this case, molasses) yields reactive OH radicals that can oxidize chloride. In summary, this study demonstrates the ability of road dust and anti-icer to influence atmospheric oxidant mixing ratios in cold-climate urban areas, and highlights previously unidentified air quality impacts of winter road maintenance decisions.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Ozônio/química , Poeira/análise , Cloro , Cloretos , Cloreto de Cálcio/análise , Sais/análise , Poluição do Ar/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental
12.
J Water Health ; 20(6): 972-984, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35768971

RESUMO

Sewage comprises multifarious information on sewershed characteristics. For instance, influent sewage quality parameters (ISQPs) (e.g., total nitrogen (TN)) are being monitored regularly at all treatment plants. However, the relationship between ISQPs and sewershed characteristics is rarely investigated. Therefore, this study statistically investigated relationships between ISQPs and sewershed characteristics, covering demographic, social, and economic properties in Tokyo city as an example of a megacity. To this end, we collected ISQPs and sewershed characteristic data from 2015 to 2020 in 10 sewersheds in Tokyo city. By principal component analysis, spatial variability of ISQPs was aggregated into two principal components (89.8% contribution in total), indicating organics/nutrients and inorganic salts, respectively. Concentrations of organics/nutrients were significantly correlated with the population in sewersheds (daytime population density, family size, age distribution, etc.). Inorganic salts are significantly correlated with land cover ratios. Finally, a multiple regression model was developed for estimating the concentration of TN based on sewershed characteristics (R2=0.97). Scenario analysis using the regression model revealed that possible population movements in response to the coronavirus pandemic would substantially reduce the concentration of TN. These results indicate close relationships between ISQPs and sewershed characteristics and the potential applicability of big data of ISQPs to estimate sewershed characteristics and vice versa.


Assuntos
Esgotos , Poluentes Químicos da Água , Nitrogênio/análise , Sais/análise , Esgotos/análise , Tóquio , Poluentes Químicos da Água/análise
13.
J Food Biochem ; 46(10): e14266, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35652286

RESUMO

Hot water treatment (HT) induces chilling injury (CI) tolerance in mango, but prolonged exposure to HT causes softening. In this sense, calcium salts stabilize the cell wall. Nevertheless, there is little information on the effect of HT combined with calcium salts (HT-Ca) on calcium absorption and cell wall stability during storage of mango at CI temperature. We evaluated the effect of quarantine HT in combination with calcium chloride (CaCl2 ), calcium citrate (CaCit), or calcium lactate (CaLac) on calcium absorption, CI tolerance, and cell wall stabilization. HT and HT-CaCl2 had the lowest CI development. HT increased firmness loss and electrolyte leakage, and HT-Ca counteracted this effect. Overall, HT-Ca treatments had a similar effect on the cell wall degrading enzymes. HT-CaCl2 was the best treatment and did not present alterations on the epicuticular wax as observed on HT. HT-CaCl2 is a useful technology to stabilize cell wall and preserve mango during chilling storage. PRACTICAL APPLICATIONS: The addition of calcium salts in an established hot water quarantine procedure for mango exportation represents a viable alternative to counteract the negative effects of this thermal treatment upon cell microstructure, maintaining its positive effect of tolerance to chilling injury. In this sense, mango producers and packers can use a HT-CaCl2 treatment to reduce the presence of chilling injury and extent the fruit shelf life and improve its commercialization. Furthermore, technical and infrastructure changes are not necessary for the packaging chain.


Assuntos
Mangifera , Purificação da Água , Cálcio , Cloreto de Cálcio/análise , Cloreto de Cálcio/farmacologia , Citrato de Cálcio/análise , Citrato de Cálcio/farmacologia , Parede Celular , Temperatura Baixa , Frutas/química , Mangifera/química , Quarentena , Sais/análise , Sais/farmacologia , Temperatura
14.
Environ Res ; 212(Pt B): 113261, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35413300

RESUMO

Atmospheric amines have attracted increasing attention due to their significant impact on new particle formation, particle hygroscopicity and particle optical properties. In this study, four low-molecule-weight amines were detected from PM2.5 filter samples collected at an urban site of Pearl River Delta (PRD) region of China in 2018 autumn. During the campaign, the mass concentrations of ambient particulate methylamine (MA, CH3NH2), dimethylamine (DMA, (CH3)2NH), trimethylamine (TMA, (CH3)3N), and diethylamine (DEA, (C2H5)2NH) were quantified at daily or 12-h resolution using an optimized Ion Chromatograph (IC) method. The total measured amine concentration was 297 ± 209 ng/m3, which can account for 0.76 ± 0.33% of PM2.5 mass concentrations. The particulate amines in PRD urban area were dominated by MA (243 ± 179 ng/m3), accounting for over 80% of total amines, then followed by DMA (49 ± 30 ng/m3, 16.5%), TMA (4 ± 2 ng/m3) and DEA (1 ± 1 ng/m3). Based on the correlation analysis, MA and DMA mainly presented as nitrate and sulfate salts. We speculate the amines tend to react with gas-phase HNO3 or particle-phase nitrate to form particulate amine salts via local process in Guangzhou. As the relative humidity (RH) increased, enhanced partitioning of amine towards the particle phase was observed. Using approach of multiple linear regression, 71% of the particulate amines in PRD urban site could be explained by acid-base process and the rest by primary emissions from combustion sources (29%).


Assuntos
Poluentes Atmosféricos , Rios , Poluentes Atmosféricos/análise , Aminas/análise , China , Carvão Mineral/análise , Monitoramento Ambiental/métodos , Nitratos/análise , Óxidos de Nitrogênio/análise , Material Particulado/análise , Sais/análise
15.
Int J Nanomedicine ; 17: 1695-1709, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35444417

RESUMO

Purpose: This study aimed to investigate the hydrolytic stability of 10-methacryloyloxydecyl dihydrogen phosphate calcium (MDP-Ca) salts with nanolayered and amorphous structures in different pH environments. Methods: The MDP-Ca salts were synthesized from MDP and calcium chloride and characterized by X-ray diffraction (XRD), nuclear magnetic resonance (NMR), and transmission electron microscopy (TEM). Inductively coupled plasma-mass spectrometry (ICP-MS) was used to quantify the release of calcium from the synthesized MDP-Ca salt, MDP-treated hydroxyapatite (MDP-HAp), and untreated HAp after soaking in acidic and neutral solutions for 1, 7, and 30 days. To study the hydrolytic process, we carried out molecular dynamics (MD) simulations of the nanolayered MCS-MD (monocalcium salt of the MDP dimer) and DCS-MD (dicalcium salt of the MDP dimer) structures, as well as of the amorphous-phase MCS-MM (monocalcium salt of the MDP monomer). Results: The TEM images showed that the nanolayered structures were partially degraded by acid attack. Based on the ICP-MS results, the hydrolysis rate of the MDP-Ca salt in acidic and neutral environments followed the order HAp > MDP-HAp > MDP-Ca salt. The MD simulations showed that, in acidic environments, clusters of MDP remained aggregated and all Ca2+ ions separated from the MDP monomer to interact with water molecules in aqueous solution. In neutral environments, Ca2+ ions always interacted with phosphate groups, OH- ions, and water molecules to form clusters centered on Ca2+ ions. Conclusion: MDP-Ca presented higher hydrolysis rates in acidic than neutral environments. Nanolayered MCS-MD possessed the highest resistance to acidic hydrolysis, followed by amorphous MCS-MM and DCS-MD.


Assuntos
Colagem Dentária , Sais , Cálcio/análise , Dentina/química , Hidrólise , Teste de Materiais , Metacrilatos/química , Cimentos de Resina/química , Sais/análise , Água
16.
Environ Sci Pollut Res Int ; 29(43): 64756-64774, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35478393

RESUMO

Any contamination in potable water leads to high risk on human health. Hence, it is inevitable to characterize water quality and assess temporal change with reference to human health. In this paper, nineteen water quality parameters from 50 sources of drinking water supply operated by state agency Uttarakhand Jal Sansthan (UJS) were analysed. The water samples were collected for pre-monsoon (May) and post-monsoon (November) seasons for the year 2010, 2011, 2018 and 2019. Multivariate analysis such as Pearson's correlation coefficient (r), K-mean, hierarchical clustering and principle component analysis (PCA) were applied to examine the drinking water quality at source sites. The strength of correlation among the parameters is reduced over the time. Cluster analysis provides six major hydro-chemical clusters in the study region. Clusters were compact during 2010-2011 and converted to overlapping structure in later period. The size of clusters was change from two clusters to six clusters during 2018-2019. These hydro-chemical clusters were examined through PCA and established six major hydro-chemical components of water quality. The physico-chemical parameters, namely, pH, alkalinity, TH, TDS, Na, K, Ca, Mg, Cl and SO4, were in PC-1, the heavy metals in PC-3, turbidity in PC-4, TC in PC-5 and PC-6 is combination of turbidity, NO3 and TC, whereas PC-2 was a mix of pH and Na and K salts. Study highlighted that the water quality has changed over the time due to runoff of plant debris, erosion, agricultural fertilizer, development activities and local geology hosts. Each PCs was mapped with associated human health issues. Result reveals that structures and pattern of PCs indicate several human health diseases over the later period with seasonal effects.


Assuntos
Água Potável , Metais Pesados , Poluentes Químicos da Água , Água Potável/análise , Monitoramento Ambiental , Fertilizantes/análise , Humanos , Metais Pesados/análise , Rios/química , Sais/análise , Poluentes Químicos da Água/análise , Qualidade da Água
17.
Molecules ; 27(4)2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35209114

RESUMO

In this work, a flow-based spectrofluorimetric method for iodine determination was developed. The system consisted of a miniaturized chip-based flow manifold for solutions handling and with integrated spectrofluorimetric detection. A multi-syringe module was used as a liquid driver. Iodide was quantified from its catalytic effect on the redox reaction between Ce(IV) and As(III), based on the Sandell-Kolthoff reaction. The method was applied for the determination of iodine in salt, pharmaceuticals, supplement pills, and seaweed samples without off-line pre-treatment. An in-line oxidation process, aided by UV radiation, was implemented to analyse some samples (supplement pills and seaweed samples) to eliminate interferences and release iodine from organo-iodine compounds. This feature, combined with the fluorometric reaction, makes this method simpler, faster, and more sensitive than the classic approach of the Sandell-Kolthoff reaction. The method allowed iodine to be determined within a range of 0.20-4.0 µmol L-1, with or without the in-line UV digestion, with a limit of detection of 0.028 µmol L-1 and 0.025 µmol L-1, respectively.


Assuntos
Iodo/análise , Preparações Farmacêuticas/análise , Sais/análise , Espectrometria de Fluorescência/instrumentação , Espectrometria de Fluorescência/métodos , Digestão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência/normas , Seringas
18.
Chem Pharm Bull (Tokyo) ; 70(2): 162-168, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35110437

RESUMO

NMR relaxometry measurement by time domain NMR (TD-NMR) is a promising technique for characterizing the properties of active pharmaceutical ingredients (APIs). This study is dedicated to identifying the salt and free base of APIs by NMR relaxometry measured by the TD-NMR technique. Procaine (PC) and tetracaine (TC) were selected as model APIs to be tested. By using conventional methods including powder X-ray diffraction and differential scanning calorimetry, this study first confirmed that the salt and free base of the tested APIs differ from each other in their crystalline form. Subsequently, measurements of T1 and T2 relaxation were performed on the tested APIs using TD-NMR. The results demonstrated that these NMR relaxometry measurements have sufficient capacity to distinguish the difference between the free base and salt of the tested APIs. Furthermore, quantification of the composition of the binary powder blends consisting of salt and free bases was conducted by analyzing the acquired T1 and T2 relaxation curves. The analysis of the T1 relaxation curves provided a partly acceptable estimation: a good estimation of the composition was observed from PC powders, whereas for TC powders the estimation accuracy changed with the free base content in the binary blends. For the analysis on T2 relaxation curves, a precise estimation of the composition was observed from all the samples. From these findings, the NMR relaxometry measurement by TD-NMR, in particular the T2 relaxation measurement, is effective for evaluating the properties of APIs having different crystalline forms.


Assuntos
Preparações Farmacêuticas/análise , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Sais/análise , Fatores de Tempo , Difração de Raios X
19.
Chem Pharm Bull (Tokyo) ; 70(2): 182-186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35110440

RESUMO

Bromine K-edge X-ray absorption near-edge structure (XANES) spectroscopy analyses were used to evaluate the crystals of the active pharmaceutical ingredients, eletriptan hydrobromide, dextromethorphan hydrobromide and scopolamine hydrobromide salts and the solid dispersion of eletriptan hydrobromide. The crystals and the solid dispersion of the active pharmaceutical ingredient (API) salts could be discriminated based on the shape of the XANES spectra. The differences in the shape of XANES spectra was ascribable to the differences in the interatomic interactions of the bromine ions based on the crystal structures. Ratio of the eletriptan hydrobromide α-form crystal in mixed powders of α-form and monohydrate crystals could be quantified by the linear-combination fitting using their XANES spectra. These results indicated that the XANES spectroscopy are a potent method for evaluating the APIs of pharmaceutical formulations even at the higher energy region around the bromine K-edge of 13470 eV.


Assuntos
Bromo/química , Hidrocarbonetos Bromados/análise , Preparações Farmacêuticas/análise , Catálise , Estrutura Molecular , Sais/análise , Espectroscopia por Absorção de Raios X
20.
Acta Crystallogr F Struct Biol Commun ; 77(Pt 12): 473-483, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34866603

RESUMO

The structures of new crystal forms of Satellite tobacco mosaic virus (STMV) are described. These belong to space groups I2, P21212 (a low-resolution form), R3 (H3) and P23. The R3 crystals are 50%/50% twinned, as are two instances of the P23 crystals. The I2 and P21212 crystals were grown from ammonium sulfate solutions, as was one crystal in space group P23, while the R3 and the other P23 crystals were grown from sodium chloride, sodium bromide and sodium nitrate. The monoclinic and orthorhombic crystals have half a virus particle as the asymmetric unit, while the rhombohedral and cubic crystals have one third of a virus particle. RNA segments organized about the icosahedral twofold axes were present in crystals grown from ammonium sulfate and sodium chloride, as in the canonical I222 crystals (PDB entry 4oq8), but were not observed in crystals grown from sodium bromide and sodium nitrate. Bromide and nitrate ions generally replaced the RNA phosphates present in the I222 crystals, including the phosphates seen on fivefold axes, and were also found at threefold vertices in both the rhombohedral and cubic forms. An additional anion was also found on the fivefold axis 5 Šfrom the first anion, and slightly outside the capsid in crystals grown from sodium chloride, sodium bromide and sodium nitrate, suggesting that the path along the symmetry axis might be an ion channel. The electron densities for RNA strands at individual icosahedral dyads, as well as at the amino-terminal peptides of protein subunits, exhibited a diversity of orientations, in particular the residues at the ends.


Assuntos
Vírus Satélite do Mosaico do Tabaco , Capsídeo , Cristalografia por Raios X , Sais/análise , Vírus Satélite do Mosaico do Tabaco/química
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