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1.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684789

RESUMO

The use of additives has generated significant attention due to their extensive application in the microbially induced calcium carbonate precipitation (MICP) process. This study aims to discuss the effects of Na-montmorillonite (Na-MMT) on CaCO3 crystallization and sandy soil consolidation through the MICP process. Compared with the traditional MICP method, a larger amount of CaCO3 precipitate was obtained. Moreover, the reaction of Ca2+ ions was accelerated, and bacteria were absorbed by a small amount of Na-MMT. Meanwhile, an increase in the total cementing solution (TCS) was not conducive to the previous reaction. This problem was solved by conducting the reaction with Na-MMT. The polymorphs and morphologies of the CaCO3 precipitates were tested by using X-ray diffraction and scanning electron microscopy. Further, when Na-MMT was used, the morphology of CaCO3 changed from an individual precipitate to agglomerations of the precipitate. Compared to the experiments without Na-MMT in the MICP process, the addition of Na-MMT significantly reduced the hydraulic conductivity (HC) of sandy soil consolidated.


Assuntos
Bentonita/metabolismo , Carbonato de Cálcio/metabolismo , Sporosarcina/metabolismo , Bentonita/química , Biotecnologia , Carbonato de Cálcio/isolamento & purificação , Precipitação Química , Cristalização , Microscopia Eletrônica de Varredura , Areia/química , Solo/química , Sporosarcina/crescimento & desenvolvimento , Difração de Raios X
2.
Dokl Biol Sci ; 494(1): 248-250, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33083883

RESUMO

The effect of the introduction of a non-ionogenic surfactant Polysorbate 20 into a sorption preparation (CB-H-BYA) on the structure of sorbent layers formed on the surface of spring wheat seeds during their pre-sowing treatment has been studied using electron microscopy. According to the results, an increase in the efficiency of sorption preparations containing Polysorbate 20 is based on an intensification of the bentonite aggregate disintegration into individual montmorillonite particles and a formation of more dense protective sorption layer providing a better protection of seeds against allelotoxins on the seed surface. The introduction of non-ionogenic surfactants into the preparation increases a sorption capacity of a bentonite-humus complex that results in a decreased gibberellin activity in a solution. Therefore, to achieve the maximum physiological activity of gibberellin in a preparation solution, it is necessary to increase its concentration from 100 to 300 mg/L. As a result, the stimulating effect increases from 36 to 55%.


Assuntos
Adsorção/efeitos dos fármacos , Polissorbatos/farmacologia , Sementes/efeitos dos fármacos , Triticum/efeitos dos fármacos , Bentonita/metabolismo , Giberelinas/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Tensoativos/farmacologia , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
3.
Toxins (Basel) ; 12(10)2020 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-33081067

RESUMO

The goal of this study was to investigate the toxicokinetic characteristics of aflatoxin G1 (AFG1) in broiler chickens and the effect of calcination of a Tunisian montmorillonite clay on the in vivo absorption of AFG1. In this study, broiler chickens were randomly distributed into four groups of 10 animals. Group 1 was administered AFG1 (2 mg/kg body weight (BW)) by single intravenous injection (IV), group 2 received an intra-crop bolus (PO) of AFG1 without any clay, group 3 was dosed AFG1 PO together with an oral bolus of purified clay (CP), and group 4 received AFG1 PO with an oral bolus of calcined clay. A significant difference in the area under the curve (AUC0-t) was observed for group 4 (6.78 ± 4.24 h*ng/mL) in comparison with group 2 (12.83 ± 4.19 h*ng/mL). A significant reduction of the oral bioavailability of AFG1 was observed for group 4 (7.61 ± 4.76%) compared with group 2 (14.40 ± 4.70%), while no significant effect was observed of CP. In this experiment, no phase I nor phase II metabolites of AFG1 were observed. These findings confirm that calcination of the purified montmorillonite clay enhances the adsorption of AFG1 in the gastrointestinal tract after oral administration, thereby reducing its bioavailability, thus reducing its toxic effects.


Assuntos
Aflatoxinas/toxicidade , Ração Animal/microbiologia , Antídotos/farmacologia , Bentonita/farmacologia , Cálcio/farmacologia , Quelantes/farmacologia , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Silicatos/farmacologia , Adsorção , Aflatoxinas/metabolismo , Animais , Antídotos/metabolismo , Bentonita/metabolismo , Disponibilidade Biológica , Biotransformação , Cálcio/metabolismo , Galinhas/metabolismo , Microbiologia de Alimentos , Absorção Gastrointestinal , Silicatos/metabolismo , Toxicocinética
4.
Int J Biol Macromol ; 164: 1737-1747, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738326

RESUMO

This work evaluated the synergic effect of carvacrol essential oil (EO) and montmorillonite (MMT) (named hybrid compound), incorporated in thermoplastic starch (TPS) films in different contents (4.5, 9, and 15 wt%). TPS films were characterized by FTIR, FT-Raman, DSC, XRD, and antimicrobial assay. FTIR and FT-Raman indicated new hydrogen bonds between hybrid and starch, altering the thermal properties and requiring more energy to destroy the TPS-hybrid bonds. XRD analysis showed slight crystallinity changes, and TPS-15 hybrid showed an amorphous structure that allows the diffusion of EO thought the films. TPS-hybrid films showed antimicrobial behavior against E. coli due to the synergistic effect of MMT and EO, which resulted in strong antimicrobial effects due to the destabilization and partial destruction of the bacteria cell membrane. The hybrid probably changed the E. coli cell permeability, respiration, and electron transport. TPS-15 hybrid sample presented the lowest crystallinity, facilitating the film's oil diffusion, maximizing the bacterium inhibitory effect, and acting as a biocidal agent. The results demonstrated that a hybrid compound is a good option for starch antimicrobial films for fresh food, such as fruits and vegetables.


Assuntos
Bentonita/farmacologia , Cimenos/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Bentonita/metabolismo , Cimenos/metabolismo , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Monoterpenos/farmacologia , Nanocompostos/química , Óleos Voláteis/farmacologia , Permeabilidade , Amido/química , Resistência à Tração
5.
Carbohydr Polym ; 240: 116307, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32475577

RESUMO

Nanocomposite film of pullulan (PULL), tempo cellulose nanofibrils (TOCNs) and, montmorillonite clay (MMT) were prepared using a solution casting method with aqueous solutions. X-ray diffraction data revealed that exfoliated MMT nanoplatelets are distributed within the PULL/TOCNs/MMT film structure. Fourier-transform infrared results revealed that there might be interactions among the TOCNs, MMT and PULL matrix led to improved tensile strength, thermal stability, water barrier properties, and decrease moisture susceptibility while maintained reasonable transparency and biodegradability of the ternary PULL nanocomposites. These excellent properties of the nanocomposites clearly indicate towards a new strategy for developing high-performance PULL-based nanocomposites by using two different types of fillers with various geometric shapes and aspect ratio. This kind of ternary nanocomposite film can be broadly used in food packaging and protection as a green and biodegradable film.


Assuntos
Bentonita/química , Celulose/química , Óxidos N-Cíclicos/química , Glucanos/química , Nanocompostos/química , Nanofibras/química , Bentonita/metabolismo , Biodegradação Ambiental , Celulose/metabolismo , Óxidos N-Cíclicos/metabolismo , Embalagem de Alimentos , Glucanos/metabolismo , Microbiologia do Solo , Resistência à Tração , Água/química
6.
Enzyme Microb Technol ; 136: 109506, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32331714

RESUMO

Biomass from oil palm frond leaves (OPFL) is an excellent reservoir of lignocellulosic material which full potential remains untapped. This study aimed to statistically optimize the covalent immobilization of Candida rugosa lipase (CRL) onto a ternary support comprised of OPFL derived nanocellulose (NC) and montmorillonite (MMT) in alginate (ALG) (CRL-ALG/NC/MMT). The coarser topology and the presence of characteristic spherical globules in the field emission scanning electron micrographs and atomic force micrographs, respectively, supported the existence of CRL on ALG/NC/MMT. In addition, amide peaks at 3478 and 1640 cm-1 in the fourier transform infrared spectra affirmed that CRL was covalently bonded to ALG/NC/MMT. The optimized Taguchi Design-assisted immobilization of CRL onto ALG/NC/MMT (7 h of immobilization, 35℃, pH 5, 7 mg/mL protein loading) gave a production yield of 92.89 % of ethyl levulinate (EL), as proven by gas chromatography-mass spectrometric ([M] +m/z 144, C7H12O3), FTIR and nuclear magnetic resonance (CAS-539-88-8) data. A higher optimal reaction temperature (50℃) and the reusability of CRL-ALG/NC/MMT for up to 9 esterification cycles substantiated the appreciable structural rigidification of the biocatalyst by ALG/NC/MMT, which improved the catalytic activity and thermal stability of the lipase.


Assuntos
Alginatos/metabolismo , Bentonita/metabolismo , Candida/enzimologia , Celulose/metabolismo , Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Biocatálise , Estabilidade Enzimática , Esterificação , Temperatura
7.
Chemosphere ; 252: 126459, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32199164

RESUMO

A 98-day research was conducted to assess the influence of dietary montmorillonite (MMT) on growth and immune competence in rainbow trout (Oncorhynchus mykiss). Fish fry (mean weight: 500 ± 35 mg) were fed with four experimental diets contained MMT at levels of 0 (as control group), 1, 2 and 4%. At the end of the experiment, the survival rate and growth parameters and serum total protein and albumin levels in MMT experimental groups was higher than the control group. Regarding humoral immune responses, fish being fed with 2 and 4% MMT diets showed the greatest and the lowest serum C3, C4 and lysozyme levels, respectively. Serum alternative complement pathway activity (ACH50) in groups fed with 1 and 2% MMT supplemented diets was higher than the other groups. At the end of the challenge test with VHSV, the mortality rate reached to 28 and 20% in the control group and 4% MMT supplemented groups, respectively, whereas fish fed with 1 and 2% MMT supplemented diets showed the lowest mortality rate (2.5%) Fish fed with 1 and 2% MMT supplemented groups showed higher head kidney IL-1ß and TNF-α genes expression compared to the other treatment groups. In addition, fish fed with 2% MMT-supplemented diet had the highest head kidney Lyz-2 gene expression. In summary, the results of this research suggests that supplementing diet with MMT at 1 or 2% improve growth and non-specific humoral immune responses and induce head kidney immune relate genes expression and disease resistance against VHS in O. mykiss.


Assuntos
Bentonita/metabolismo , Dieta , Fatores Imunológicos/metabolismo , Oncorhynchus mykiss/fisiologia , Ração Animal/análise , Animais , Suplementos Nutricionais , Resistência à Doença , Doenças dos Peixes , Expressão Gênica , Rim Cefálico/metabolismo , Oncorhynchus mykiss/metabolismo
8.
Poult Sci ; 99(3): 1311-1319, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32111307

RESUMO

This study was conducted to evaluate the effects and combinational effects of Bacillus subtilis (BS) and montmorillonite (MMT) on laying performance, gut mucosal oxidation status, and intestinal immunological and physical barrier functions of laying hens. Three hundred sixty laying hens (29-week-old) were randomly assigned to a 2 × 2 factorial arrangement of treatments (n = 6) for 10 wk as follows: (1) basal diet; (2) the basal diet plus 5 × 108 cfu BS/kg; (3) the basal diet plus 0.5 g MMT/kg; and (4) the basal diet plus 5 × 108 cfu BS/kg and 0.5 g MMT/kg. Dietary supplementation with BS increased egg production and egg mass, the activities of catalase (CAT) and total superoxide dismutase in the intestinal mucosa, and villus height and villus height-to-crypt depth ratio of the jejunum (P < 0.05) but downregulated the mRNA expression levels of toll-like receptor 4 and myeloid differentiation factor 88 (MyD88) in the duodenum and jejunum, interleukin 1 beta in the duodenum, and nuclear factor kappa B P65 (NF-κB P65) and tumor necrosis factor alpha in the jejunum (P < 0.05). Dietary supplementation with MMT increased egg production and egg mass, the concentration of secretory immunoglobulin A in the duodenum, and the occludin mRNA expression level in the jejunum (P < 0.05) but reduced feed conversion ratio, malondialdehyde concentration in the duodenum and jejunum, and the mRNA expression level of MyD88 in the jejunum (P < 0.05). In addition, there was an interaction effect between BS and MMT supplementation on the CAT activity and the MyD88 mRNA expression level in the duodenum and the mRNA expression level of occludin in the jejunum (P < 0.05). In conclusion, dietary BS and MMT and their combination may improve the intestinal health status of laying hens, which may contribute to the increase in hens' laying performance.


Assuntos
Bacillus subtilis/química , Bentonita/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bentonita/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Intestinos/imunologia , Oxirredução , Probióticos , Distribuição Aleatória , Reprodução
9.
J Dairy Sci ; 103(4): 3125-3132, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32037179

RESUMO

The objective of this study was to evaluate the capacity of 6 mycotoxin binders (MTB) to adsorb 3 AA and 4 water-soluble vitamins (WSV). Two experiments were conducted in in vitro conditions to simulate postruminal digestion with pepsin, malic acid, citric acid, acetic acid, and lactic acid at pH 3.0 and intestinal digestion with bile salts and pancreatin extract at pH 6.5. Experiment 1 was conducted with AA, and experiment 2 was conducted with WSV. Within experiment, main factors were the MTB (bentonite, clinoptiolite, sepiolite, montmorillonite, activated carbon, and yeast cell walls), the substrate (AA: Lys, Met, and Thr; WSV: B1, B2, B3, and B6), and the incubation strategy (substrates alone or mixed). Data were analyzed for the effects of main factors and their interactions. In experiment 1, the adsorption average for AA when incubated separately was 44.3%, ranging from 62.4% for Thr by clinoptiolite to 20.0% for Thr by activated carbon. When incubated together, the average adsorption was reduced to 19.9%, suggesting competition among substrates for adsorption. Adsorption ranged from 29.8% for Thr by yeast cell walls to 5.6% for Met by clinoptiolite, but there were significant interactions among MTB and AA. In experiment 2, the average adsorption of WSV when incubated separately or together was 34.1 and 45.1%, respectively, suggesting possible synergies among substrates. When vitamins were incubated separately, adsorption ranged from 90.5% for vitamin B1 to 4.0% for vitamin B3 by montmorillonite. Vitamins B1 (except by yeast cell walls) and B6 (except by bentonite, sepiolite, and montmorillonite) were absorbed the most, and vitamin B3 was absorbed the least (except by activated carbon and yeast cell walls, which were least together with vitamin B2). When vitamins were incubated together, adsorption ranged from 97.0% for vitamin B1 by montmorillonite to 0% for vitamin B2 by activated carbon and vitamin B3 by bentonite. Vitamins B1 by all MTB and B6 by clinoptiolite, sepiolite, and yeast cell walls were the most adsorbed, and vitamin B3 (except by activated carbon and yeast cell wall) was the least absorbed. There were significant interactions among MTB and WSV. Mycotoxin binders have a high degree of adsorption of the AA and WSV tested in in vitro conditions, which may limit their bioavailability. Results also suggest that when substrates were incubated together some interactions for adsorption occurred, which were competitive among AA and synergic among vitamins.


Assuntos
Aminoácidos/metabolismo , Micotoxinas/metabolismo , Complexo Vitamínico B/metabolismo , Adsorção , Animais , Bentonita/metabolismo , Parede Celular , Carvão Vegetal/metabolismo , Feminino , Humanos , Masculino , Gravidez , Riboflavina/metabolismo , Tiamina/metabolismo , Leveduras
10.
J Sci Food Agric ; 100(2): 785-793, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31612485

RESUMO

BACKGROUND: Red onion is popular in cuisines worldwide and is valued for its potential medicinal properties. Red onion is an important source of several phytonutrients such as flavonoids, thiosulfinates and other sulfur compounds, recognized as important elements of the diet. Nowadays, there is the need of producing food enriched in health benefit compounds. In this study, pads of sulfur bentonite (SB) with the addition of orange residue (OR) or olive pomace (OP) were used to improve the quality of red onion. The experiment was conducted for 3 months in the field to evaluate the phytochemicals of differently amended red onion. RESULTS: Treated plants were better in quality than controls. Antioxidant activity, detected as DPPH, ORAC and ABTS, was highest in plants grown in the presence of SB enriched with agricultural wastes, particularly SB-OR. Polyphenols increased in all treated plants. The volatile fraction was clearly dominated by sulfur compounds that are strictly related to the concentration of the aroma precursors S-alkenyl cysteine sulfoxides. The greater amount of thiosulfinates in treated compared with untreated onion evidenced that SB pelletized with agricultural wastes can represent a new formulation of organic fertilizer able to improve the beneficial properties of onion. The results highlighted that the best red onion quality was obtained using SB-OR pads. CONCLUSION: The use of SB bound with agricultural wastes represents a novel strategy to increase bio-compounds with beneficial effects on human health, to enhance the medical and economic values of sulfur-loving crops, with important consequences on the bio and green economy. © 2019 Society of Chemical Industry.


Assuntos
Antioxidantes/análise , Bentonita/análise , Produção Agrícola/métodos , Fertilizantes/análise , Cebolas/química , Extratos Vegetais/análise , Enxofre/análise , Resíduos/análise , Antioxidantes/metabolismo , Bentonita/metabolismo , Olea/química , Cebolas/crescimento & desenvolvimento , Cebolas/metabolismo , Extratos Vegetais/metabolismo , Enxofre/metabolismo
11.
Mycotoxin Res ; 35(3): 243-252, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30903558

RESUMO

This work characterizes the adsorption of aflatoxin B1 (AFB1), ochratoxin A (OTA), and zearalenone (ZEN) by dry micronized olive pomace (OliPom) and grape stems (GrapStem). Their performance was compared with that of three other materials, activated carbon (ActCarb), bentonite (Bent), and a commercial product (ComProd). Experiments were conducted in vitro at several pH values using buffer solutions. For OTA and ZEA, the strongest adsorbent was ActCarb, with 5 mg/mL being sufficient to bind > 99% of all the mycotoxins. For AFB1, ComProd and Bent were the most effective adsorbents, as 0.5 mg/mL bound > 95% of this mycotoxin. Among the two agro by-products, GrapStem was the strongest binder, with 10 mg/mL being sufficient to bind at least 90% of all the mycotoxins (except OTA at pH 7). OliPom was the least efficient material, but at a concentration of 30 mg/mL, its performance was similar to GrapStem. Adsorption isotherms were calculated, and ActCarb showed the maximum adsorption capacity (Qmax), with values that ranged from 19 to 24 µg/mg for pH 2 and from 17 to 20 µg/mg for pH 7. ComProd, Bent, and GrapStem showed more similar Qmax between them (1.4-4.4 µg/mg for pH 2 and 0.5-4.8 µg/mg for pH 7).


Assuntos
Aflatoxina B1/metabolismo , Bentonita/metabolismo , Ocratoxinas/metabolismo , Olea/metabolismo , Vitis/metabolismo , Zearalenona/metabolismo , Adsorção , Carvão Vegetal/química , Caules de Planta/metabolismo , Ligação Proteica
12.
Appl Environ Microbiol ; 84(14)2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29752271

RESUMO

Microbial mineralization (corrosion, decomposition, and weathering) has been investigated for its role in the extraction and recovery of metals from ores. Here we report our application of biomineralization for the microbial enhanced oil recovery in low-permeability oil reservoirs. It aimed to reveal the etching mechanism of the four Fe(III)-reducing microbial strains under anaerobic growth conditions on Ca-montmorillonite. The mineralogical characterization of Ca-montmorillonite was performed by Fourier transform infrared spectroscopy, X-ray powder diffraction, scanning electron microscopy, and energy-dispersive spectrometry. Results showed that the microbial strains could efficiently reduce Fe(III) at an optimal rate of 71%, alter the crystal lattice structure of the lamella to promote interlayer cation exchange, and efficiently inhibit Ca-montmorillonite swelling at a rate of 48.9%.IMPORTANCE Microbial mineralization is ubiquitous in the natural environment. Microbes in low-permeability reservoirs are able to facilitate alteration of the structure and phase of the Fe-poor minerals by reducing Fe(III) and inhibiting clay swelling, which is still poorly studied. This study aimed to reveal the interaction mechanism between Fe(III)-reducing bacterial strains and Ca-montmorillonite under anaerobic conditions and to investigate the extent and rates of Fe(III) reduction and phase changes with their activities. Application of Fe(III)-reducing bacteria will provide a new way to inhibit clay swelling, to elevate reservoir permeability, and to reduce pore throat resistance after water flooding for enhanced oil recovery in low-permeability reservoirs.


Assuntos
Bactérias/metabolismo , Bentonita/metabolismo , Biomineralização , Campos de Petróleo e Gás/microbiologia , Cátions/metabolismo , Argila/microbiologia , Compostos Férricos/metabolismo , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Permeabilidade , Difração de Raios X
13.
Chemosphere ; 200: 427-436, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29501033

RESUMO

Though abundant studies have targeted the characterization of heavy metal adsorption by either clay minerals or bacteria, to date, minimal literature exists which specifically assesses bacteria-clay mineral interactions in the context of metal immobilization. The adsorption of Pb onto montmorillonite, Pseudomonas putida, and their 1:1, 2:1, 6:1 and 12:1 mass ratio composites were investigated by using a combination of atomic force microscope (AFM), X-ray diffraction (XRD), surface complexation modeling (SCM), Pb-LIII edge extended X-ray absorption fine structure (EXAFS) spectroscopy and isothermal titration calorimetry (ITC). The SCM and EXAFS demonstrated that Pb ions coordinate with phosphoryl and carboxyl functional groups on bacteria at low and high concentrations, respectively. The ITC analysis found adverse enthalpy values for Pb adsorption to permanent (-2.91 kJ/mol) and variable charge sites (6.93 kJ/mol) on montmorillonite. The ternary bridging model, EXAFS and ITC provide molecular and thermodynamic evidences for the formation of enthalpy driven (-4.74 kJ/mol) ternary complex (>AlO-Pb-PO4) in the composites. The proportion for the bridging structures increased at pH > 5 and high bacterial mass ratios. The formation of ternary complex did not result in the enhanced adsorption of Pb on the composites, but promoted the allocation of Pb on the mineral fraction. The results obtained from SCM, EXAFS and ITC may provide an essential assumption for predicting the speciation and fate of Pb in soils and associated environments.


Assuntos
Silicatos de Alumínio/química , Bentonita/química , Calorimetria/métodos , Chumbo/química , Minerais/química , Pseudomonas putida/fisiologia , Difração de Raios X/métodos , Adsorção , Aderência Bacteriana , Bentonita/metabolismo , Argila , Chumbo/metabolismo , Microscopia de Força Atômica/métodos , Modelos Químicos , Pseudomonas putida/química , Solo/química , Propriedades de Superfície
14.
Food Chem Toxicol ; 114: 316-324, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29496528

RESUMO

Populations consuming aflatoxin (AF) and fumonisin (FN)-contaminated foods may be at increased risk for hepatocellular carcinoma (HCC) and developmental disorders; consequently, development of intervention strategies to reduce AF/FN-induced liver disease and adverse health effects in humans could be very useful. Calcium montmorillonite clay (NovaSil) has been shown to absorb AF in vitro, in multiple animal models, as well as in human studies. In the present study, we aimed to evaluate whether uniform particle size NovaSil (UPSN) possessed an ability to modulate the co-carcinogenic potentials of aflatoxin B1 (AFB1) and fumonisin B1 (FB1) in F344 rats. Sequential treatment of FB1 following AFB1 synergistically induces preneoplastic alterations as well as liver damage, indicating that AFB1 acts as an initiator while FB1 as a promoter in the carcinogenesis model, confirming findings from previous studies. The enterosorbent agent UPSN clay at dose of up to 0.5% in diet was shown to be effective in modulating the toxicity and carcinogenicity of co-exposure to AFB1 and FB1, as demonstrated by significant reduction in number and size of hepatic GST-P+ foci, in alterations indicative of liver toxicity, and in levels of AFB1 and FB1 biomarkers.


Assuntos
Aflatoxina B1/toxicidade , Silicatos de Alumínio/administração & dosagem , Bentonita/administração & dosagem , Fumonisinas/toxicidade , Hepatopatias/tratamento farmacológico , Adsorção , Aflatoxina B1/química , Aflatoxina B1/metabolismo , Silicatos de Alumínio/química , Silicatos de Alumínio/metabolismo , Animais , Bentonita/química , Bentonita/metabolismo , Argila , Fumonisinas/química , Fumonisinas/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Hepatopatias/etiologia , Hepatopatias/metabolismo , Masculino , Ratos , Ratos Endogâmicos F344
15.
J Dairy Sci ; 101(4): 3008-3020, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29428756

RESUMO

The study was conducted to examine the effect of supplementing bentonite clay with or without a Saccharomyces cerevisiae fermentation product (SCFP; 19 g of NutriTek + 16 g of MetaShield, both from Diamond V, Cedar Rapids, IA) on the performance and health of dairy cows challenged with aflatoxin B1 (AFB1). Twenty-four lactating Holstein cows (64 ± 11 d in milk) were stratified by parity and milk production and randomly assigned to 1 of 4 treatment sequences. The experiment had a balanced 4 × 4 Latin square design with 6 replicate squares, four 33-d periods, and a 5-d washout interval between periods. Cows were fed a total mixed ration containing 36.1% corn silage, 8.3% alfalfa hay, and 55.6% concentrate (dry matter basis). Treatments were (1) control (no additives), (2) toxin (T; 1,725 µg of AFB1/head per day), (3) T + clay (CL; 200 g/head per day; top-dressed), and (4) CL+SCFP (CL+SCFP; 35 g/head per day; top-dressed). Cows were adapted to diets from d 1 to 25 (predosing period) and then orally dosed with AFB1 from d 26 to 30 (dosing period), and AFB1 was withdrawn from d 31 to 33 (withdrawal period). Milk samples were collected twice daily from d 21 to 33, and plasma was sampled on d 25 and 30 before the morning feeding. Transfer of ingested AFB1 into milk aflatoxin M1 (AFM1) was greater in T than in CL or CL+SCFP (1.65 vs. 1.01 and 0.94%, respectively) from d 26 to 30. The CL and CL+SCFP treatments reduced milk AFM1 concentration compared with T (0.45 and 0.40 vs. 0.75 µg/kg, respectively), and, unlike T, both CL and CL+SCFP lowered AFM1 concentrations below the US Food and Drug Administration action level (0.5 µg/kg). Milk yield tended to be greater during the dosing period in cows fed CL+SCFP compared with T (39.7 vs. 37.7 kg/d). Compared with that for T, plasma glutamic oxaloacetic transaminase concentration, indicative of aflatoxicosis and liver damage, was reduced by CL (85.9 vs. 95.2 U/L) and numerically reduced by CL+SCFP (87.9 vs. 95.2 U/L). Dietary CL and CL+SCFP reduced transfer of dietary AFB1 to milk and milk AFM1 concentration. Only CL prevented the increase in glutamic oxaloacetic transaminase concentration, and only CL+SCFP prevented the decrease in milk yield caused by AFB1 ingestion.


Assuntos
Aflatoxina B1/farmacologia , Silicatos de Alumínio/metabolismo , Bentonita/metabolismo , Bovinos/metabolismo , Leite/química , Saccharomyces cerevisiae/química , Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Animais , Bentonita/administração & dosagem , Bovinos/imunologia , Argila , Dieta/veterinária , Suplementos Nutricionais/análise , Feminino , Fermentação , Nível de Saúde , Lactação , Distribuição Aleatória
16.
Fish Shellfish Immunol ; 75: 27-31, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29409931

RESUMO

The effect of Sodium Bentonite (SB) enriched diet on growth performance, innate immune response, and disease resistance in stinging catfish, Heteropneustes fossilis against Aeromonas hydrophila is reported. The infected fish fed with 5% SB had the maximum weight gain diet (PWG %) and specific growth rate (SGR %) were 26% and 29% when compared to 14% and 17% with 10% diet. Similarly the phagocytic activity increased significantly when infected fish were fed with 5% or 10% SB diets during the experimental period; the complement, respiratory burst and lysozyme activities were also significantly enhanced on weeks 2 and 4. The lower cumulative mortality (10% and 15%) was observed when the infected fish were fed with 5% and 10% SB diets for 30 days. The results suggest that the infected H. fossilis after administration of 5% and 10% SB enriched diets for 30 days had significantly improved growth performance, innate immunity, and disease resistance against A. hydrophilla. Hence, sodium bentonite can be used as a feed additive to stimulate immunity and for disease resistance in the effective production of economically valuable freshwater catfish, H. fossilis.


Assuntos
Silicatos de Alumínio/metabolismo , Bentonita/metabolismo , Peixes-Gato/crescimento & desenvolvimento , Peixes-Gato/imunologia , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , Aeromonas hydrophila/fisiologia , Silicatos de Alumínio/administração & dosagem , Ração Animal/análise , Animais , Bentonita/administração & dosagem , Peixes-Gato/metabolismo , Argila , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/imunologia
17.
Environ Sci Pollut Res Int ; 25(23): 22348-22355, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28744678

RESUMO

This paper aimed to investigate the variation of preserving organic matter bound in the interlayer space of montmorillonite (Mt) induced by a microbe metabolic process. We selected Bacillus pumilus as the common soil native bacteria. The alteration of d 001 value, functional group, and C,N organic matter contents caused by bacteria were analyzed by XRD, FTIR, and elementary analyzer, respectively. XRD results showed that the d 001 value of montmorillonite increased with the concentration decreasing and decreased with the culture time increasing after interacting with bacteria indicating the interlayer space of montmorillonite was connected with the organic matter. The findings of long-term interaction by resetting culture conditions implied that the montmorillonite buffered the organic matter when the nutrition was enough and released again when the nutrition was lacking. The results of the elementary analyzer declared the content of organic matter was according to the d 001 value of montmorillonite and N organic matter which played a major impact. FTIR results confirmed that the Si-O stretching vibrations of Mt were affected by the functional group of organic matter. Our results showed that the montmorillonite under the influence of soil bacteria has a strong buffering capacity for preserving organic matter into the interlayer space in a short-term. It might provide critical implications for understanding the evolution process and the preservation of fertilization which was in the over-fertilization or less-fertilization conditions on farmland.


Assuntos
Bentonita/química , Bentonita/metabolismo , Microbiologia do Solo , Bacillus pumilus/fisiologia , Solo , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
18.
Environ Sci Pollut Res Int ; 25(2): 1340-1349, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29086178

RESUMO

The present study was conducted to investigate the effect of graded levels of dietary bentonite supplementation on growth performance, carcass traits, nutrient digestibility, and histopathology of certain organs in rabbits fed a diet naturally contaminated with aflatoxin. In total, 125 weanling New Zealand White male rabbits were randomly assigned to five treatment groups each of five replicates. Treatments were as follows: T1, basal diet with no aflatoxin and no additives (positive control diet, PCD); T2, basal diet naturally contaminated with 150 ppb aflatoxin and no additives (negative control diet, NCD); T3, NCD plus 0.5% Egyptian bentonite; T4, NCD plus 1% Egyptian bentonite; and T5, NCD plus 1% Egyptian bentonite. The experiment lasted for 8 weeks. Results showed a significant decrease (P < 0.05) in the body weight and the body weight gain in the NCD, while they were improved (P < 0.05) in groups fed diets supplemented with different levels of bentonite. The relative weight of the liver and kidneys were higher in the NCD, while the liver weight was relatively high in the group fed NCD supplemented with 0.5% bentonite, and it was not significant in other bentonite-supplemented groups. Bentonite supplementation improved the digestibility coefficients of various nutrients. Bentonite addition decreased the histopathological lesions in liver, kidney, and intestine caused by aflatoxin-infected diets. In conclusion, bentonite supplementation overcame the negative effect of aflatoxin, enhanced growth performance traits, decreased the relative weights of the liver and the kidney which are usually increased by aflatoxin, caused significant improvement in nutrients' digestibility, and decreased the histopathological lesions caused by aflatoxin-infected diets. The level of 2% bentonite is recommended for ameliorating the aflatoxin effects.


Assuntos
Aflatoxinas/toxicidade , Bentonita/metabolismo , Digestão/efeitos dos fármacos , Coelhos/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bentonita/administração & dosagem , Dieta/veterinária , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Coelhos/crescimento & desenvolvimento , Distribuição Aleatória , Ganho de Peso/efeitos dos fármacos
19.
Innate Immun ; 23(8): 648-655, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28958208

RESUMO

This study was aimed at investigating whether dietary copper/zinc-loaded montmorillonite (Cu/Zn-Mt) could alleviate Escherichia coli LPS-induced intestinal injury through pro- and anti-inflammatory signaling pathways (TLRs, NLRs and TGF-ß1) in weaned piglets. Eighteen 21-d-old pigs were randomly divided into three groups (control, LPS and LPS + Cu/Zn-Mt). After 21 d of feeding, pigs in the LPS group and LPS + Cu/Zn-Mt group received i.p. administration of LPS, whereas pigs in the control group received saline. At 4 h post-injection, jejunum samples were collected for analysis. The results indicated that, compared with the LPS group, supplemental Cu/Zn-Mt increased transepithelial electrical resistance, the expressions of anti-inflammatory cytokines (TGF-ß1) in mRNA and protein levels, and decreased FD4 and the mRNA expression of pro-inflammatory cytokines (TNF-α, IL-6, IL-8 and IL-1ß). The pro-inflammatory signaling pathways results demonstrated that Cu/Zn-Mt supplementation decreased the mRNA levels of TLR4 and its downstream signals (MyD88, IRAK1, TRAF6) but had no effect on NOD1 and NOD2 signals. Cu/Zn-Mt supplementation did not affect NF-κB p65 mRNA abundance, but down-regulated its protein expression. The anti-inflammatory signaling pathways results showed supplemental Cu/Zn-Mt also increased TßRII, Smad4 and Smad7 mRNA expressions. These findings suggested dietary Cu/Zn-Mt attenuated LPS-induced intestinal injury by alleviating intestinal inflammation, influencing TLR4-MyD88 and TGF-ß1 signaling pathways in weaned pig.


Assuntos
Bentonita/metabolismo , Cobre/metabolismo , Intestinos/fisiologia , Fator 88 de Diferenciação Mieloide/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Zinco/metabolismo , Animais , Bentonita/química , Cobre/química , Citocinas/metabolismo , Inflamação/genética , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/imunologia , Transdução de Sinais , Suínos , Desmame , Zinco/química
20.
Water Res ; 120: 165-173, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28486167

RESUMO

Cyanobacteria and their toxins present potential hazard to consumers of water from lakes, reservoirs and rivers, thus their removal via water treatment is essential. The capacity of nano-composites of Octadecyltrimethyl-ammonium (ODTMA) complexed with clay to remove cyanobacterial and their toxins from laboratory cultures and from lake water, was evaluated. Column filters packed with micelles of ODTMA complexed with bentonite and granulated were shown to significantly reduce the number of cyanobacteria cells or filaments and their corresponding toxins from laboratory cultures. Fluorescence measurements demonstrated that cyanobacteria cells lost their metabolic activity (photosynthesis) upon exposure to the micelle (ODTMA)-bentonite complex, or ODTMA monomers. The complex efficiently removed cyanobacteria toxins with an exceptional high removal rate of microcystins. The effectiveness of the complex in elimination of cyanobacteria was further demonstrated with lake water containing cyanobacteria and other phytoplankton species. These results and model calculations suggest that filters packed with granulated composites can secure the safety of drinking water in case of a temporary bloom event of toxic cyanobacteria.


Assuntos
Bentonita/metabolismo , Cianobactérias , Micelas , Compostos de Amônio , Toxinas Bacterianas , Cátions , Lagos , Microcistinas
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