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1.
Polymers (Basel) ; 16(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38794510

RESUMO

The flammability properties of polymers and polymeric composites play an important role in ensuring the safety of humans and the environment; moreover, flame-retardant materials ensure a greater number of applications. In the present study, we report the obtaining of polypropylene (PP) composites contain a mixture of two green flame retardants, lignin and clinoptilolite, by melt extrusion. These additives are abundantly found in nature. Fourier transform infrared (FT-IR), thermogravimetric analysis (TGA), mechanical properties, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), cone calorimetry, UL-94, and carbonized residues analysis were carried out. TGA analysis shows that PPGFR-10 and PPGFR-20 compounds presented better thermal stability with respect to PP without flame retardants. The conical calorimetric evaluation of the composites showed that PPGFR-10 and PPGFR-20 presented decreases in peak heat release rates (HRRs) of 9.75% and 11.88%, respectively. The flammability of the composites was evaluated with the UL-94 standard, and only the PPGFR-20 composite presented the V-0 and 5VB classification, which indicates good flame-retardant properties. Additives in the polymer matrix showed good dispersion with few agglomerates. The PPGFR-20 composite showed an FRI value of 1.15, higher percentage of carbonized residues, and UL-94 V-0 and 5VB rating, suggesting some kind of synergy between lignin and clinoptilolite, but only at high flame-retardant concentrations.

2.
Heliyon ; 10(1): e24006, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38234893

RESUMO

Population growth in recent years has led to increased wastewater production and pollution of water resources. This situation also heavily affects Bolivia, so wastewater treatment methods and materials suitable for Bolivian society should be explored. This study investigated the natural Bolivian Zeolite (BZ) and its NaCl-modified structure (NaBZ) as adsorbents for cadmium removal from water. The natural BZ and the modified form NaBZ were investigated by different physicochemical characterization techniques. Furthermore, XPS and FT-IR techniques were used to investigate the adsorption mechanisms. The cadmium adsorption on BZ and NaBZ was analyzed using various mathematical models, and the Langmuir model provided a better description of the experimental adsorption data with cadmium adsorption capacities of 20.2 and 25.6 mg/g for BZ and NaBZ, respectively. The adsorption followed the pseudo-second order kinetics. The effect of different parameters, such as initial cadmium concentration and pH on the adsorption was studied. In addition, the results of the regeneration test indicated that both BZ and NaBZ can be regenerated by using hydrochloric acid (HCl). Finally, the adsorption experiment of BZ and NaBZ on a real water sample (brine from Salar de Uyuni salt flat) containing a mixture of different heavy metals was carried out. The results obtained in this study demonstrate the effectiveness of natural BZ and modified NaBZ in the removal of heavy metals from wastewater.

3.
Toxins (Basel) ; 15(9)2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37755945

RESUMO

Aflatoxins can cause intoxication and poisoning in animals and humans. Among these molecules, aflatoxin B1 (AFB1) is the most dangerous because of its carcinogenic and mutagenic properties. To mitigate these effects, clay adsorbents are commonly included in the diet of animals to adsorb the carcinogens and prevent their absorption in the gastrointestinal tract. In this study, four clays, three smectites (C-1, C-2, and C-3), and one zeolite (C-4), were compared as adsorbents of AFB1 and trace inorganic nutrients using an in vitro gastrointestinal model for poultry. Characterization of the clays using Fourier transform infrared spectroscopy revealed characteristic bands of smectites in C-1, C-2, and C-3 (stretching vibrations of Si-O, Al-O-Si, and Si-O-Si). The C-4 presented bands related to the bending vibration of structural units (Si-O-Si and Al-O-Si). X-ray diffraction analysis showed that C-1 is a montmorillonite, C-2 is a beidellite, C-3 is a beidellite-Ca-montmorillonite, and C-4 is a clinoptilolite. The elemental compositions of the clays showed alumina, silica, iron, calcium, and sodium contents. The cation exchange capacity was higher in C-3 clay (60.2 cmol(+)/kg) in contrast with the other clays. The AFB1 adsorption of C-1 was the highest (98%; p ˂ 0.001), followed by C-2 (94%). However, all the clays also sequestered trace inorganic nutrients (Fe, Mn, Zn, and Se). Both smectites, montmorillonite and beidellite, were the most suitable for use as adsorbents of AFB1.


Assuntos
Oligoelementos , Animais , Humanos , Adsorção , Aflatoxina B1 , Argila , Bentonita , Aves Domésticas , Carcinógenos
4.
Artigo em Inglês | MEDLINE | ID: mdl-37277584

RESUMO

The use of natural zeolite clinoptilolite to reduce the leaching rate of potentially toxic elements such as Cd, Pb, and Mn in soil from mine tailings was studied. Soil from the surroundings of the mine El Bote in Zacatecas, Mexico, was analyzed, and the zeolite was characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, and nitrogen physisorption. An ammonium-exchange method for the zeolite was employed. Leaching experiments using packed columns with polluted soil and zeolite mixtures were carried out and the effect of the pH of the carrier solutions was studied. Incorporation of zeolite in the soil achieved a beneficial increase in pH, from 5.03 to 6.95. The concentration of Cd and Mn was reduced when zeolite was present in the column and the ammonium-modified zeolite with ammonia also enhanced the concentration reduction of metallic species in leachates in a range of 28 to 68%. The first-order model best fits the experimental data, suggesting that the leaching rate is controlled by concentration difference between the liquid and the soil matrix. These results demonstrate the potential for using natural zeolite clinoptilolite to reduce the leaching rate of potentially toxic elements in soil from mine tailings.

5.
Trop Anim Health Prod ; 54(5): 281, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36074277

RESUMO

This study aimed to assess the effect of adding clinoptilolite in the diet on uterine health and reproductive performance in multiparous lactating dairy cows managed in a tropical pasture-based system above 2500 m of altitude. Seventy-seven multiparous Holstein crossbred cows from two farms were allocated randomly into two groups: clinoptilolite supplemented cows (CLG, n = 42) and non-supplemented cows as control (CG, n = 35). Cows from CLG were supplemented with clinoptilolite from 30 days (50 g/cow/day) before to 60 days after calving (200 g/cow/day). In CLG cows, percentages of uterine PMN leukocytes (P < 0.0001) and proportion of subclinical endometritis (P = 0.0187) were lower than in CG. The interval calving to first corpus luteum was shorter (P = 0.0759) in CLG than CG, and calving to first service interval was similar between treatments. Cows from CLG became pregnant 35 days earlier than CG cows (P = 0.0224). On farm A, calving to conception interval was 18.1 days longer in CLG than in CG (P = 0.3750); in farm B, this interval was 86.2 days shorter in CLG than in CG (P = 0.0002). In conclusion, daily addition of clinoptilolite in the diet decreased the percentage of uterine PMN leukocytes, the proportion of cows with subclinical endometritis, and shortened the calving-conception interval in multiparous lactating dairy cows.


Assuntos
Endometrite , Animais , Bovinos , Dieta/veterinária , Endometrite/prevenção & controle , Endometrite/veterinária , Feminino , Lactação , Leucócitos , Período Pós-Parto , Gravidez , Zeolitas
6.
Molecules ; 28(1)2022 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-36615274

RESUMO

The detection of emerging contaminants in bodies of water has steadily increased in recent years, becoming a severe problem threatening human and ecosystem health. Developing new materials with adsorption properties to remove these pollutants represents an important step toward a potential solution. In this paper, a polybutylene adipate terephthalate (PBAT) nanofibrous membrane incorporating clinoptilolite zeolite was developed and its excellent performance in removing tetracycline (TC) and methylene blue (MB) from water was demonstrated. The composite membrane was prepared in two steps: firstly, a homogeneous dispersion of clinoptilolite (1 wt% respect to polymer) in a PBAT solution (12.6 wt%) was electrospun; secondly, the electrospun membrane was subjected to an acid treatment that improved its wettability through the protonation of the surface silanol groups of clinoptilolite. The resulting membrane was hydrophilic and showed higher adsorption for TC (800 mg/g) and MB (100 mg/g), using a low dose (90 mg/L) powdered zeolite. The maximum removal capacity was obtained at neutral pH, being the cation exchange reaction the main adsorption mechanism. Pseudo-second-order kinetics and Henry's law agree well with the proposed chemisorption and the high affinity of TC and MB for the adsorbent. The material can be reused after the removal process without generating additional contamination, although losing some effectivity.


Assuntos
Poluentes Químicos da Água , Zeolitas , Humanos , Zeolitas/química , Azul de Metileno/química , Adsorção , Ecossistema , Poluentes Químicos da Água/química , Antibacterianos , Tetraciclina , Água/química , Concentração de Íons de Hidrogênio , Cinética , Adipatos
7.
Environ Sci Pollut Res Int ; 29(53): 79808-79815, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34783951

RESUMO

Diazepam has been detected in water sources around the world affecting the quality of drinking water. Even in small quantities, recent studies have proven the negative effects of the drug on human body. Since traditional water and sewage treatment do not remove this type of contaminant, it became interesting to evaluate forms to remove them from water sources. A cheap and eco-friendly alternative to remove this drug from the water is through adsorption using the natural clinoptilolite zeolite as an adsorbent. This work goal was to study the characterizations of clinoptilolite, such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometer (XRD), and Fourier transform infrared spectroscopy (FTIR) and analyze the potential of this material as an adsorbent. Kinetic studies and isotherm analysis were performed in batch. The results showed the potential of the natural zeolite to remove the pollutant in an aqueous medium reaching a maximum adsorption capacity of 8.25 mg g-1. The adsorption process followed a pseudo-second-order kinetics indicating that the adsorption was based on a chemisorption process. The isotherms curves shown favorable adsorption and the Langmuir isotherm model fit the experimental data better.


Assuntos
Água Potável , Poluentes Químicos da Água , Zeolitas , Humanos , Zeolitas/química , Adsorção , Cinética , Diazepam , Esgotos , Poluentes Químicos da Água/análise , Termodinâmica , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de Hidrogênio
8.
Rev. bras. ciênc. avic ; 24(3): eRBCA-2021-1466, 2022. tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1382142

RESUMO

This study was aimed at determining the effects of dietary zeolite (clinoptilolite) supplementation on fattening performance, slaughter characteristics, and some blood and visceral organ parameters in Japanese quails. For this purpose, 140 (4x35) four-day-old Japanese quail chicks (Coturnix coturnix japonica) were randomly assigned to 4 groups with 4 replicates (9+9+9+8), and the study was continued for a period of 31 days. The groups were fed on a basal diet supplemented with 0% of clinoptilolite (control group), 1.5% of clinoptilolite (Z1.5), 3% of clinoptilolite (Z3) and 6% of clinoptilolite (Z6). For the female quails, the best blood TOS and liver TAS levels were detected in Z3 and Z1.5, respectively. For the male quails, the best blood TAS and liver TOS levels were determined in Z1.5. Histopathological examination demonstrated that dietary supplementation with 1.5% of zeolite had increased the height of the intestinal villi in both male and female quails, and had reduced hepatic lipidosis in female quails. Female quails displayed significantly increased levels of hepatic lipidosis in Z3 and Z6, and liver hepatitis in Z3. In result, it is suggested that zeolite, a hydrated aluminosilicate, in its form containing 90.2% of clinoptilolite, can be incorporated as a feed supplement into quail basal diets at a rate of 3%, owing to its positive effect on fattening performance. Furthermore, the use of zeolite may also contribute to maintaining animal health by reducing humidity in poultry houses and feed.(AU)


Assuntos
Animais , Feminino , Zeolitas/química , Suplementos Nutricionais/efeitos adversos , Coturnix/fisiologia , Fenômenos Fisiológicos Sanguíneos , Vísceras/fisiologia
9.
Molecules ; 26(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361830

RESUMO

This work describes the newly discovered zeolites in the eastern region of Cuba. In the researched area, there have been no previous studies of natural zeolite exploration. Therefore, the results shown here are new. The main object of this research is to analyse five samples of zeolites and demonstrate their pozzolanic capacity and the possibility of their usage in the industrial manufacturing of pozzolanic cements. The study of the samples was performed by X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM). A chemical analysis (CAQ) to determine the quality of the samples as pozzolans was performed, by determining the total SiO2, reactive SiO2, total CaO, reactive CaO, Al2O3, MgO and the insoluble residue (I.R.). Lastly, an eight-day pozzolanicity analysis (PA) was carried out to determine the pozzolanic reactivity of the samples. The results obtained by XRD, XRF and SEM established that the researched zeolite samples have two main zeolitic phases: mordenite and clinoptilolite. Altered volcanic glass, quartz and smectite (montmorillonite) are the secondary phases. The results of the chemical quality analysis (CAQ) showed that the samples contain a considerable amount of reactive SiO2 and reactive CaO, as well as a low content of insoluble residue, which reinforces their properties as pozzolans. The results of the pozzolanicity analysis (PA) concluded that the analysed samples actively react with Ca(OH)2 after eight days. Based on all the results mentioned above, it is established that both mordenite and clinoptilolite behave like pozzolans and can be recommended for the manufacture of pozzolanic cements, which have more effective properties than Portland cement, in terms of physical, chemical and mechanical strength, low heat of hydration, resistance to sulphates, low CO2 emissions to the atmosphere and negligible impacts on the environment.

10.
Environ Geochem Health ; 43(5): 2037-2048, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33244649

RESUMO

Helicobacter pylori can be found in the stomach of about half of the humans, and a large population can be associated with serious diseases. To survive in the stomach H. pylori increases the pH locally by producing ammonia which binds to H+ becoming ammonium. This work investigated the effects on the in-vitro growth of H. pylori of a natural cation-exchanger mainly composed (≈70%) of clinoptilolite and mordenite. The zeolitized material from Cuba was evaluated in its original form (M), as well as in its Na- (M-Na) and Zn-exchanged (M-Zn) counterparts. In the preliminary agar cup diffusion test, H. pylori revealed susceptibility only to M-Zn, with a direct relationship between concentration and width of inhibition halo. Further experiments evidenced that bacterium replication increases when ammonium is supplied to the growth medium and decreases when zeolites subtract NH4+ via ion exchange. Due to the multi-cationic population of its zeolites M was not effective enough in removing ammonium and, in the Minimum Inhibitory Concentration (MIC) test, allowed bacterial growth even at a concentration of 50 mg/mL. Inhibition was achieved with M-Na because it contained sodium zeolites capable of maximizing NH4+ subtraction, although the MIC was high (30 mg/mL). M-Zn evidenced a more effective inhibitory capacity, with a MIC of 4 mg/mL. Zinc has antimicrobial properties and H. pylori growth was affected by Zn2+ released from clinoptilolite and mordenite. These zeolites, being more selective towards NH4+ than Zn2+, can also subtract ammonium to the bacterium, thus enhancing the efficacy of M-Zn.


Assuntos
Silicatos de Alumínio/farmacologia , Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Zeolitas/farmacologia , Zinco/farmacologia , Silicatos de Alumínio/química , Compostos de Amônio/metabolismo , Compostos de Amônio/farmacologia , Antibacterianos/química , Cuba , Helicobacter pylori/crescimento & desenvolvimento , Troca Iônica , Testes de Sensibilidade Microbiana , Sódio/química , Zeolitas/química , Zinco/química
11.
Waste Manag ; 101: 259-267, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634812

RESUMO

Over the past few years, supercritical water oxidation (ScWO) has shown great potential for application to landfill leachate treatment, providing substantial organic matter degradation in terms of biochemical oxygen demand (BOD), chemical oxygen demand (COD), and total organic carbon (TOC). However, the conversion of ammonia, which is present at high concentrations in leachates, is the rate-limiting step during ScWO and usually requires large amounts of oxidants, the addition of catalysts, or severe operating conditions. Aiming at proposing a treatment system that effectively removes both organic matter and ammonia from leachate, this paper evaluates the intensification of the ScWO process through ion exchange with zeolite. Thus, ScWO was operated under a pressure of 23 MPa at 600 and 700 °C, without the addition of oxidants. The zeolite (clinoptilolite) was used without any modification inside a glass column. The ScWO (600 °C)/zeolite system removed 90% ammoniacal nitrogen (NH3-N), 100% nitrite (NO2-N), 98% nitrate (NO3-N), color, and turbidity, 81% TOC, and 74% COD, suggesting that this system is a promising alternative for leachate treatment. However, the final NH3-N and COD values were slightly above the limits (20 and 200 mg L-1, respectively) stipulated by the Brazilian environmental legislation. These results suggest that further improvements are still required for the application of the intensified ScWO to be feasible. Notably, ammonium-saturated clinoptilolite is amenable for regeneration or can be applied to soil as a slow-release fertilizer.


Assuntos
Poluentes Químicos da Água , Zeolitas , Brasil , Troca Iônica , Água
12.
Semina ciênc. agrar ; 40(6): 2673-2682, Nov.-Dec. 2019. tab
Artigo em Inglês | VETINDEX | ID: biblio-1501550

RESUMO

Addition of zeolite to caninedietscan improve fecal characteristics, reducing its moisture and odor. The objective of this study was to evaluate the effects of an increasing dietary inclusion of zeolite on nutrient and energy digestibility, fecal characteristics, and diet palatability for dogsfed diets containing high soybean meal level. Two experiments were performed. The first experiment evaluated the effect of increasing concentrations (0, 10, 20, 30, 40, or 50 g/kg) of zeolite (clinoptilolite) in extruded dog foods on diet digestibility and fecal quality. Six adult dogs were distributed to treatments arranged in a 6 x 6 Latin square design. The second assessed the effect of 20 or 50 g clinoptilolite per kg of diet on food palatability, where in 20 dogs were distributedinto two tests, in a completely randomized experimental design (0 vs.20 g/kg and 0 vs. 50 g/kg zeolite). Despite the small variation, dietary zeolite inclusion reduced diet metabolizable energy content (15.4 to 14.7 MJ/kg, P 0.05) in ammonia nitrogen, sialic acid, fecal pH,or diet palatability.The inclusion of up to 50 g natural clinoptilolite per kg of diet increases fDM content, maintains adequate fecal score and has no negative impact on diet palatability.


O uso de zeólita na alimentação de cães é realizado visando melhorar as características fecais, reduzindo sua umidade e odor. O presente trabalho teve como objetivo avaliar a inclusão crescente de zeólita sobre a digestibilidade dos nutrientes e energia, características fecais e palatabilidade de cães alimentados com dieta contendo altos níveis de farelo de soja. Foram realizados dois experimentos. O primeiro avaliou a inclusão crescente de zeólita (clinoptilolita): 0, 10, 20, 30, 40 e 50 g/kg em dietas extrusadas para cães sobre a digestibilidade e qualidade das fezes. Foram utilizados seis cães adultos, em quadrado latino 6x6. No segundo experimento avaliou-se a inclusão de 20 e 50 g/kg de clinoptilolita na dieta sobre a palatabilidade em cães. Foram utilizados 20 cães em delineamento inteiramente casualizado em dois tratamentos (0 vs.20g/kg e 0 vs. 50 g/kg de zeólita). Embora com pequena variação, a inclusão de zeólita resultou em redução linear da energia metabolizável (15,4 a 14,7 MJ/kg, P 0,05). Não foram encontradas diferenças na palatabilidade das dietas. A inclusão de até 50 g/kg de clinoptilolita natural aumenta o teor de matéria seca fecal, com manutenção de adequado escore fecal, sem afetar negativamente a palatabilidade das dietas.


Assuntos
Animais , Cães , Digestão , Fezes , Ração Animal , Zeolitas/administração & dosagem
13.
Semina Ci. agr. ; 40(6): 2673-2682, Nov.-Dec. 2019. tab
Artigo em Inglês | VETINDEX | ID: vti-27106

RESUMO

Addition of zeolite to caninedietscan improve fecal characteristics, reducing its moisture and odor. The objective of this study was to evaluate the effects of an increasing dietary inclusion of zeolite on nutrient and energy digestibility, fecal characteristics, and diet palatability for dogsfed diets containing high soybean meal level. Two experiments were performed. The first experiment evaluated the effect of increasing concentrations (0, 10, 20, 30, 40, or 50 g/kg) of zeolite (clinoptilolite) in extruded dog foods on diet digestibility and fecal quality. Six adult dogs were distributed to treatments arranged in a 6 x 6 Latin square design. The second assessed the effect of 20 or 50 g clinoptilolite per kg of diet on food palatability, where in 20 dogs were distributedinto two tests, in a completely randomized experimental design (0 vs.20 g/kg and 0 vs. 50 g/kg zeolite). Despite the small variation, dietary zeolite inclusion reduced diet metabolizable energy content (15.4 to 14.7 MJ/kg, P < 0.05) and the coefficient of total tract apparent digestibility of dry matter (0.773 to 0.740, P < 0.05). Fecal dry matter (fDM) content increased as zeolite concentrations increased (30.4% to 36.1%, P < 0.05), but fecal score had no effect. Zeolite concentrations caused no changes (P > 0.05) in ammonia nitrogen, sialic acid, fecal pH,or diet palatability.The inclusion of up to 50 g natural clinoptilolite per kg of diet increases fDM content, maintains adequate fecal score and has no negative impact on diet palatability.(AU)


O uso de zeólita na alimentação de cães é realizado visando melhorar as características fecais, reduzindo sua umidade e odor. O presente trabalho teve como objetivo avaliar a inclusão crescente de zeólita sobre a digestibilidade dos nutrientes e energia, características fecais e palatabilidade de cães alimentados com dieta contendo altos níveis de farelo de soja. Foram realizados dois experimentos. O primeiro avaliou a inclusão crescente de zeólita (clinoptilolita): 0, 10, 20, 30, 40 e 50 g/kg em dietas extrusadas para cães sobre a digestibilidade e qualidade das fezes. Foram utilizados seis cães adultos, em quadrado latino 6x6. No segundo experimento avaliou-se a inclusão de 20 e 50 g/kg de clinoptilolita na dieta sobre a palatabilidade em cães. Foram utilizados 20 cães em delineamento inteiramente casualizado em dois tratamentos (0 vs.20g/kg e 0 vs. 50 g/kg de zeólita). Embora com pequena variação, a inclusão de zeólita resultou em redução linear da energia metabolizável (15,4 a 14,7 MJ/kg, P < 0,05) e do coeficiente de digestibilidade aparente da matéria seca (0,773 a 0,740, P < 0,05). A matéria seca fecal aumentou com os níveis crescentes de zeólita (30,4% a 36,1%, P < 0,05) não afetando, entretanto, o escore das fezes. Os níveis de zeólita não causaram diferença quanto ao nitrogênio amoniacal, ácido siálico e pH fecal (P > 0,05). Não foram encontradas diferenças na palatabilidade das dietas. A inclusão de até 50 g/kg de clinoptilolita natural aumenta o teor de matéria seca fecal, com manutenção de adequado escore fecal, sem afetar negativamente a palatabilidade das dietas.(AU)


Assuntos
Animais , Cães , Zeolitas/administração & dosagem , Ração Animal , Digestão , Fezes
14.
Environ Geochem Health ; 40(6): 2657-2665, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29881882

RESUMO

Two different natural zeolites from Cuba and Mexico, which are already being used as contemporaneous drugs or dietary supplements in Germany and Mexico, respectively, are applied in a comparative study of their histamine-binding capacities as a function of their particle sizes. The zeolites are characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) and N2-sorption measurements (BET surface areas). The Cuban zeolite contains clinoptilolite and mordenite as major phases (78% zeolite), whereas the Mexican one contains only clinoptilolite (65% zeolite). Both zeolites are apparently free from fibrous materials according to SEM. Both zeolites adsorb significant amount of histamine under the experimental conditions. Nevertheless, the results showed that the histamine-binding capacity of the Cuban zeolite is higher than the Mexican one and the smaller the particle size of zeolite, the higher the histamine-binding capacity. This difference could be due to the variation in their mineralogical compositions resulting in varied BET surface areas. Thus, the high histamine-binding capacities of Cuban zeolites seem to be due at least partly to the presence of the large-pore zeolite mordenite, providing high total pore volumes, which will be discussed in detail. For the first time, we have shown that the mineralogical compositions of natural zeolites and their particle sizes play a key role in binding histamine, which is one of the most important regulators in human physiology.


Assuntos
Silicatos de Alumínio/química , Histamina/metabolismo , Zeolitas/química , Adsorção , Cuba , Alemanha , Humanos , México , Tamanho da Partícula , Difração de Raios X
15.
Rev. MVZ Córdoba ; 22(1): 5631-5637, Jan.-Apr. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-896911

RESUMO

ABSTRACT Objective. To determine whether short term supplemantation at two levels (1 or 2 g/kg) of clinoptilolite (CLNP) in the colostrum of dairy calves had any effect on total weight gain (TWG) and mean daily gain of weight (mdwg). Materials and methods. A total of 24 clinically healthy calves without diarrhea were assigned in a subset of three major groups of calves were studied: group I (n=8) received colostrum with clnp at the rate of 1/kg started immediately following calving at 12 and 24 hours, for a total of 2 doses. Group II consisted of calves (n=8) receiving colostrum with clnp at the rate of 2/kg within the same interval as the first experimental group. The last group III, which served as control, received solely colostrum. Results. Group had significant effect on weight (kg) of Holstein calves [twg (mean±SE)- control: 12.66±0.349, group I: 14.73±0.414, group II: 14.19±0.468, p<0.01; mdwg (mean±SE)-control: 0.338±0.0155, group I: 0.396±0.0189, group II: 0.397±0.0196, p<0.05]. There was a significant difference observed for twg (p<0.01) and mdwg (p<0.05) among control group and both clnp treatment groups. Conclusions. The results showed that the addition of both levels of clinoptilolite administration via colostrum appeared to enhance twg and mdwg in newborn calves without having any observable adverse effect.


RESUMEN Objetivo. Determinar si la suplementación a corto plazo en 2 niveles (1 o 2 g/kg) de clinoptilolita (CLNP) en el calostro de terneros lecheros tiene algún efecto sobre la ganancia de peso total (TWG) y la ganancia media diaria de peso (MDWG). Materiales y métodos. Se asignó un total de 24 terneros clínicamente sanos sin diarrea en un subconjunto de los tres grupos principales de terneros que fueron estudiados: grupo I (n = 8) recibieron calostro con CLNP a razón de 1 g/kg inmediatamente después del parto a las 12 y 24 horas, para un total de 2 dosis. Grupo II consistió de terneros (n = 8) que recibieron calostro con CLNP a razón de 2 kg / dentro del mismo intervalo que el primer grupo experimental. El último grupo III, que sirvió como control, recibió únicamente calostro. Resultados. Grupo tuvo un efecto significativo sobre el peso (kg) de terneros Holstein [GTT (media±DE) - Control: 12.66 ± 0.349, el grupo I: 14.73 ± 0.414, el grupo II: 14.19±0.468, p<0.01; mdwg (media±DE) - Control: 0.338±0.0155, el grupo I: 0.396±0.0189, grupo II: 0.397 ± 0.0196, p<0.05]. Hubo una diferencia significativa para TWG (p<0.01) y mdwg (p<0.05) entre el grupo control y ambos grupos de tratamiento CLNP. Conclusiones. Los resultados mostraron que la adición de los dos niveles de clinoptilolita a través del calostro mejoró TWG y MDWG en terneros recién nacidos sin tener ningún efecto adverso observable.

16.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);69(1): 191-197, jan.-fev. 2017. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-836684

RESUMO

O objetivo deste trabalho foi avaliar o efeito da inclusão de 0,5% da zeólita natural clinoptilolita na dieta de frangos de corte sobre o consumo de água, ração e características das excretas. Foi conduzido um ensaio em gaiolas metabólicas, com frangos de corte de linhagem comercial, no período de 14 a 23 dias de idade. O experimento foi constituído de dois grupos de aves, sendo que um recebeu dieta sem inclusão de zeólitas (controle) e outro dieta com inclusão de 0,5% de zeólita (clinoptilolita) em rações isonutritivas, em um delineamento inteiramente ao acaso, com 10 repetições de 10 aves. Avaliou-se o consumo de água e de ração, nas excretas, pH, teor de nitrogênio total e umidade. A inclusão de 0,5% de zeólitas naturais na dieta não alterou (P>0,05) o consumo de água e de ração e o teor de nitrogênio das excretas, entretanto, reduziu (P<0,05) o pH e a umidade das excretas. Conclui-se que a inclusão de 0,5% de zeólitas naturais na dieta de frangos de corte reduz o pH e a umidade das excretas e pode ser utilizada como aditivo alimentar sem prejudicar o consumo de água e de ração.(AU)


The aim of this study was to evaluate the addition of 0.5% natural zeolites (clinoptilolite) to the diet of broilers and their effect on water and feed intake and excreta characteristics. The test was carried out in metabolic cages, with commercial line broilers, in the period from 14 to 23 days old. The experiment was conducted with two groups of broilers: one group received diet without zeolite inclusion (control) and the other received a diet with 0.5% inclusion of zeolite (clinoptilolite) in balanced diets, in a completely randomized design, with 10 replicates of 10 broilers. Water and feed intake, pH, total nitrogen, and moisture of excreta were evaluated. The inclusion of 0.5% of natural zeolites in the diet did not change (P>0.05) the water and feed intake and total nitrogen of excreta, nevertheless, it decreased (P<0.05) the pH and moisture of excreta. We conclude that the addition of 0.5% natural zeolites to the diet of broilers decreases pH and moisture of excreta and can be used as feed additive without compromising water and feed intake.(AU)


Assuntos
Animais , Galinhas/metabolismo , Dieta/veterinária , Zeolitas/análise , Amônia/análise , Nitrogênio/análise
17.
Arq. bras. med. vet. zootec. (Online) ; 69(1): 191-197, jan.-fev. 2017. tab
Artigo em Português | VETINDEX | ID: vti-690978

RESUMO

O objetivo deste trabalho foi avaliar o efeito da inclusão de 0,5% da zeólita natural clinoptilolita na dieta de frangos de corte sobre o consumo de água, ração e características das excretas. Foi conduzido um ensaio em gaiolas metabólicas, com frangos de corte de linhagem comercial, no período de 14 a 23 dias de idade. O experimento foi constituído de dois grupos de aves, sendo que um recebeu dieta sem inclusão de zeólitas (controle) e outro dieta com inclusão de 0,5% de zeólita (clinoptilolita) em rações isonutritivas, em um delineamento inteiramente ao acaso, com 10 repetições de 10 aves. Avaliou-se o consumo de água e de ração, nas excretas, pH, teor de nitrogênio total e umidade. A inclusão de 0,5% de zeólitas naturais na dieta não alterou (P>0,05) o consumo de água e de ração e o teor de nitrogênio das excretas, entretanto, reduziu (P<0,05) o pH e a umidade das excretas. Conclui-se que a inclusão de 0,5% de zeólitas naturais na dieta de frangos de corte reduz o pH e a umidade das excretas e pode ser utilizada como aditivo alimentar sem prejudicar o consumo de água e de ração.(AU)


The aim of this study was to evaluate the addition of 0.5% natural zeolites (clinoptilolite) to the diet of broilers and their effect on water and feed intake and excreta characteristics. The test was carried out in metabolic cages, with commercial line broilers, in the period from 14 to 23 days old. The experiment was conducted with two groups of broilers: one group received diet without zeolite inclusion (control) and the other received a diet with 0.5% inclusion of zeolite (clinoptilolite) in balanced diets, in a completely randomized design, with 10 replicates of 10 broilers. Water and feed intake, pH, total nitrogen, and moisture of excreta were evaluated. The inclusion of 0.5% of natural zeolites in the diet did not change (P>0.05) the water and feed intake and total nitrogen of excreta, nevertheless, it decreased (P<0.05) the pH and moisture of excreta. We conclude that the addition of 0.5% natural zeolites to the diet of broilers decreases pH and moisture of excreta and can be used as feed additive without compromising water and feed intake.(AU)


Assuntos
Animais , Zeolitas/análise , Dieta/veterinária , Galinhas/metabolismo , Amônia/análise , Nitrogênio/análise
18.
Ciênc. rural ; Ciênc. rural (Online);46(8): 1456-1459, Aug. 2016. tab
Artigo em Inglês | LILACS | ID: lil-784198

RESUMO

ABSTRACT: This study aimed to evaluate the inclusion of Yucca schidigera extract and zeolite (Clinoptilolite) added to the diets for dogs and its effect on apparent digestibility coefficients (ADC) of diet components (dry matter, organic matter, crude protein, acid hydrolyzed fat, and energy) and urinary pH. Twenty-one adult Beagles, males and females, body weight mean of 12.5±1.5kg and four and a half years old, distributed in a completely randomized design with seven replicates per treatment within three experimental treatments: control (no addition of Yucca schidigera and zeolite), Yucca schidigera (375ppm) and zeolite (1%), administered in the encapsulated form of the supplement. The ADC of diet components and urinary pH were not affected by the inclusion of additives (P>0.05), except the ADC acid hydrolyzed fat showed reduction with Yucca schidigera supplementation compared to the other treatments (P<0.05). The addition of 375ppm of Yucca schidigera extract reduced the digestibility of dietary fat by dogs and both Yucca schidigera extract and zeolite did not affect the urinary pH of dogs.


RESUMO: O objetivo deste trabalho foi avaliar a inclusão do extrato de Yucca schidigera e da zeólita (Clinoptilolita) nas dietas para cães e seus efeitos sobre os coeficientes de digestibilidade aparente (CDA) dos componentes da dieta (matéria seca, matéria orgânica, proteína bruta, extrato etéreo em hidrólise ácida e energia) e no pH urinário. Foram utilizados 21 cães Beagles, machos e fêmeas, com peso médio de 12,5±1,5kg e quatro anos e meio de idade, distribuídos em delineamento inteiramente casualizado com sete repetições para cada um dos três tratamentos experimentais: controle (sem adição de Yucca schidigera e zeólita), Yucca schidigera (375ppm) e zeólita (1%), administrados na forma de suplemento encapsulado. Os CDA dos componentes da dieta e o pH urinário não foram afetados pela inclusão dos aditivos (P>0,05), exceto o CDA do extrato etéreo em hidrólise ácida, que reduziu com a suplementação de Yucca schidigera em comparação aos demais tratamentos (P<0,05). A adição de 375ppm de extrato de Yucca schidigera reduziu a digestibilidade da gordura dietética pelos cães e tanto a adição de Yucca schidigera como a de zeólita não alteraram o pH urinário.

19.
Ci. Rural ; 46(8): 1456-1459, ago. 2016. tab
Artigo em Inglês | VETINDEX | ID: vti-22569

RESUMO

This study aimed to evaluate the inclusion of Yucca schidigera extract and zeolite (Clinoptilolite) added to the diets for dogs and its effect on apparent digestibility coefficients (ADC) of diet components (dry matter, organic matter, crude protein, acid hydrolyzed fat, and energy) and urinary pH. Twenty-one adult Beagles, males and females, body weight mean of 12.5±1.5kg and four and a half years old, distributed in a completely randomized design with seven replicates per treatment within three experimental treatments: control (no addition of Yucca schidigera and zeolite), Yucca schidigera (375ppm) and zeolite (1%), administered in the encapsulated form of the supplement. The ADC of diet components and urinary pH were not affected by the inclusion of additives (P>0.05), except the ADC acid hydrolyzed fat showed reduction with Yucca schidigera supplementation compared to the other treatments (P<0.05). The addition of 375ppm of Yucca schidigera extract reduced the digestibility of dietary fat by dogs and both Yucca schidigera extract and zeolite did not affect the urinary pH of dogs.(AU)


O objetivo deste trabalho foi avaliar a inclusão do extrato de Yucca schidigera e da zeólita (Clinoptilolita) nas dietas para cães e seus efeitos sobre os coeficientes de digestibilidade aparente (CDA) dos componentes da dieta (matéria seca, matéria orgânica, proteína bruta, extrato etéreo em hidrólise ácida e energia) e no pH urinário. Foram utilizados 21 cães Beagles, machos e fêmeas, com peso médio de 12,5±1,5kg e quatro anos e meio de idade, distribuídos em delineamento inteiramente casualizado com sete repetições para cada um dos três tratamentos experimentais: controle (sem adição de Yucca schidigera e zeólita), Yucca schidigera (375ppm) e zeólita (1%), administrados na forma de suplemento encapsulado. Os CDA dos componentes da dieta e o pH urinário não foram afetados pela inclusão dos aditivos (P>0,05), exceto o CDA do extrato etéreo em hidrólise ácida, que reduziu com a suplementação de Yucca schidigera em comparação aos demais tratamentos (P<0,05). A adição de 375ppm de extrato de Yucca schidigera reduziu a digestibilidade da gordura dietética pelos cães e tanto a adição de Yucca schidigera como a de zeólita não alteraram o pH urinário.(AU)


Assuntos
Animais , Cães , Fenômenos Fisiológicos da Nutrição Animal , Yucca , Zeolitas/administração & dosagem , Digestão/fisiologia , Aditivos Alimentares , Equilíbrio Ácido-Base
20.
Mater Sci Eng C Mater Biol Appl ; 60: 246-254, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26706528

RESUMO

Chitosan films can be used as wound dressings for the treatment of chronic wounds and severe burns. The antimicrobial properties of these films may be enhanced by the addition of silver. Despite the antimicrobial activity of silver, several studies have reported the cytotoxicity as a factor limiting its biomedical applications. This problem may, however, be circumvented by the provision of sustained release of silver. Silver zeolites can be used as drug delivery platforms to extend the release of silver. The objective of this study was to evaluate the addition of clinoptilolite and A-type zeolites in chitosan films. Sodium zeolites were initially subjected to ion-exchange in a batch reactor. Films were prepared by casting technique using a 2% w/w chitosan solution and two zeolite doses (0.1 or 0.2% w/w). Films were characterized by thermal analysis, color analysis, scanning electron microscopy, X-ray diffraction, and water vapor permeation. The results showed that films present potential for application as dressing. The water vapor permeability is one of the main properties in wound dressings, the best results were obtained for A-type zeolite/chitosan films, which presented a brief reduction of this property in relation to zeolite-free chitosan film. On the other hand, the films containing clinoptilolite showed lower water vapor permeation, which may be also explained by the best distribution of the particles into the polymer which also promoted greater thermal resistance.


Assuntos
Quitosana/química , Membranas Artificiais , Zeolitas/química , Microscopia Eletrônica de Varredura , Difração de Raios X
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