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1.
Biology (Basel) ; 10(4)2021 Apr 20.
Article in English | MEDLINE | ID: mdl-33924088

ABSTRACT

Obesity caused by a high-fat diet (HFD) affects gut microbiota linked to the risk of type-2 diabetes (T2D). This study evaluates live cells and ethanolic extract (SEL) of Lactobacillus sakei Probio65 and Lactobacillus plantarum Probio-093 as natural anti-diabetic compounds. In-vitro anti-diabetic effects were determined based on the inhibition of α-glucosidase and α-amylase enzymes. The SEL of Probio65 and Probio-093 significantly retarded α-glucosidase and α-amylase enzymes (p < 0.05). Live Probio65 and Probio-093 inhibited α-glucosidase and α-amylase, respectively (p < 0.05). In mice fed with a 45% kcal high-fat diet (HFD), the SEL and live cells of both strains reduced body weight significantly compared to HFD control (p < 0.05). Probio-093 also improved blood glucose level compared to control (p < 0.05). The gut microbiota modulatory effects of lactobacilli on HFD-induced diabetic mice were analyzed with qPCR method. The SEL and live cells of both strains reduced phyla Deferribacteres compared to HFD control (p < 0.05). The SEL and live cells of Probio-093 promoted more Actinobacteria (phyla), Bifidobacterium, and Prevotella (genus) compared to control (p < 0.05). Both strains exerted metabolic-modulatory effects, with strain Probio-093 showing more prominent alteration in gut microbiota, substantiating the role of probiotics in gut microbiome modulations and anti-diabetic effect. Both lactobacilli are potential candidates to lessen obesity-linked T2D.

2.
Ultrason Sonochem ; 64: 104993, 2020 Jun.
Article in English | MEDLINE | ID: mdl-32018135

ABSTRACT

MXene, a new family of two dimensional materials, was utilized as a sonocatalyst in an ultrasonic treatment (US) process for removal of methylene blue (MB) and acid blue 80 (AB). The physico-chemical properties of MXene were characterized using scanning electron microscopy, transmission electron microscopy, porosimetry, and a zeta potential analyzer. Degradation of dyes by US was systemically investigated under several experimental conditions including: power density of US (45, 90, 135, and 180 W L-1), frequency of US (28 and 970 kHz), pH of dye solution (3.5, 7, and 10.5), solution temperature (293, 303, and 313 K), and addition of hydroxyl radical promotor (H2O2) and scavenger (t-BuOH) to concentrations of 25 mM. Based on the experimental results, the quantity of H2O2, which was used as an indicator of hydroxyl radical concentration, was an important factor in determining the degradation rate of MB and AB in this US study. Additionally, synergetic indices for removal of both dyes were higher than 1.0 in all cases, indicating the outstanding efficiency of MXene as a sonocatalyst in the US reactor for removal of both, due to an increase in both (i) the quantity of H2O2 in the US reactor and (ii) active sites for adsorbates from dispersion effects. A stability test on MXene in the US process was conducted using X-ray diffraction and five-cycle recycling performance tests. Based on our experimental data, MXene can be utilized as a sonocatalyst in the US process for a high removal rate for dyes (e.g., MB).

3.
Ecotoxicol Environ Saf ; 182: 109396, 2019 Oct 30.
Article in English | MEDLINE | ID: mdl-31276888

ABSTRACT

We report herein the sonochemical synthesis of a lanthanum dioxide carbonate (La2O2CO3) and zinc ferrite (ZnFe2O4)-loaded reduced graphene oxide (LZF-rGO) nanoheterostructure for ultrasound (US)-assisted degradation of methyl orange (MO) from water. The MO was chosen as a model organic dye due to its toxicological and biodegradable-resistant properties. The LZF-rGO catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results of characterizations confirmed successful synthesis of sonocatalyst. Among different removal systems, US/LZF-rGO displayed outstanding sonodegradation performance for degradation of MO. The maximum removal efficiency of 75.9% was achieved using 0.2 g/L sonocatalyst, 20 mg/L MO, and 0.71 W/cm2 US power intensity for 65 min. MO can be partially adsorbed on LZF-rGO but mostly sonodegraded by reactive radical species. The reaction conditions were optimized by investigating the effect of key operating parameters, including the sonocatalyst dosage, initial MO concentration, US power intensity, presence of inorganic salts, and use of an enhancer, on the decolorization of MO. The degradation intermediates produced from MO during the sonocatalytic process were identified by UPLC®/MS-MS, and possible mechanism and pathway for the degradation of MO in the US/LZF-rGO system were also proposed. Reusability experiments with this sonocatalyst revealed a less than 10% drop in the degradation efficiency after four adsorption-desorption cycles.


Subject(s)
Coloring Agents/chemistry , Graphite/chemistry , Lanthanum/chemistry , Nanostructures/chemistry , Water Pollutants, Chemical/chemistry , Carbonates , Catalysis , Ferric Compounds , Magnetics , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Models, Chemical , Oxides/chemistry , Photoelectron Spectroscopy , Water , X-Ray Diffraction , Zinc , Zinc Compounds , Zinc Oxide/chemistry
4.
Chemosphere ; 231: 82-92, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31128355

ABSTRACT

Graphene oxide (GO) and metal-organic framework (MOF) as adsorbents were applied to removal of Pb(II) with comprehensive characterizations and various experimental conditions. Various characterizations were conducted to clarify the physico-chemical properties of adsorbents. The analyses of adsorption experiments included (i) dosage amounts, (ii) isotherm and kinetic studies, and (iii) several factors related to water chemistry (i.e., solution pH, background ions, and humic acid). The maximum equilibrium adsorption capacity (qe) for Pb(II) using the GO and MOF was 555 and 108 mg g-1, respectively, as determined in the optimum dosage experiments. Although the surface area of the MOF (629 m2 g-1) was much larger than that of the GO (19.8 m2 g-1), the adsorption capacity of the MOF was five times lower due to electrical repulsion. Thus, the MOF was utilized as the control group for comparison with the GO to evaluate the adsorption mechanisms in the experiments related to surface charge (i.e., under various pH and humic acid conditions). The adsorption isotherms and kinetics model determined using GO followed the Langmuir model (R2 > 0.99) and pseudo-second-order model (R2 > 0.99), respectively. Additionally, three adsorption-desorption cycles were conducted with the GO adsorbent to evaluate the maintenance of the removal ratio after regeneration and the equilibrium adsorption capacity was determined. Finally, the adsorption of other heavy metals (i.e., Cu(II), Cd(II), and Zn(II)), separately and in mixtures, was also evaluated to determine the selectivity of the adsorbents.


Subject(s)
Graphite/chemistry , Lead/analysis , Metal-Organic Frameworks/chemistry , Water Pollutants, Chemical/analysis , Adsorption , Cadmium/analysis , Copper/analysis , Humic Substances/analysis , Lead/chemistry , Oxides/chemistry , Zinc/analysis
5.
Bioresour Technol ; 281: 179-187, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30822638

ABSTRACT

The widespread occurrence of endocrine-disrupting compound and pharmaceutical active compounds such as bisphenol A (BPA) and sulfamethoxazole (SMX) in natural freshwater resources can cause serious environmental problems even at low exposure levels. In this work, in order to remove BPA and SMX from aqueous solutions, a novel biochar-supported magnetic CuZnFe2O4 composite (CZF-biochar) was synthesized by a facile one-pot hydrothermal process. After characterization studies, the key factors affecting BPA and SMX adsorption on CZF-biochar were comprehensively investigated. The primary mechanisms for BPA and SMX adsorption included charge-assisted H-bonding, hydrophobic, and π-π electron donor-acceptor interactions. In summary, considering the fast kinetics, high adsorption properties, easy magnetic separation, and recyclability for multiple reuses, the CZF-biochar composite has potential for the removal of BPA, SMX, and potentially other emerging organic contaminants from contaminated soil and water.


Subject(s)
Benzhydryl Compounds/chemistry , Charcoal/chemistry , Ferric Compounds/chemistry , Phenols/chemistry , Sulfamethoxazole/chemistry , Adsorption , Hydrophobic and Hydrophilic Interactions , Magnetics
6.
Appl Surf Sci ; 471: 8-17, 2019.
Article in English | MEDLINE | ID: mdl-32801406

ABSTRACT

Reduced graphene oxide (rGO) hybridized with magnetite and/or elemental silver (rGO/magnetite, rGO/silver, and rGO/magnetite/silver) nanoparticles were evaluated as potential adsorbents for toxic heavy metal ions (Cd (II), Ni(II), Zn(II), Co(II), Pb(II), and Cu(II)). Although the deposition of iron oxide and silver nanoparticles on the rGO nanosheets played an inhibitory role in metal ion adsorption, the metal adsorption efficiency by the nanohybrids (NHs) was still higher than that reported for many other sorbents (e.g., activated biochar, commercial resins, and nanosized hydrated Zr(IV) oxide particles). X-ray photoelectron spectroscopy analyses revealed that complexation with deprotonated adsorbents and cation exchange was an important mechanism for Cd(II) ion removal by the rGO and NHs. Competitive adsorption tests using multi metals showed that the adsorption affinity of metal ions on the rGO and its NHs follows the order (Cu(II), Zn(II)) > Ni(II) > Co(II) > (Pb(II), Cd(II)), which is similar to the order observed for single-metal adsorption experiments. These results can be explained by the destabilization abilities of the rGO and NHs, as well as the ionic radii of the considered metal ions. Our findings demonstrate the feasibility of using rGO-based NHs as highly efficient adsorbents for heavy metal removal from water.

7.
Chemosphere ; 205: 719-727, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29730472

ABSTRACT

This research investigated the removal of carbamazepine (CBZ) and diclofenac (DCF) in water using ultrasonic (US) treatment in the absence or presence of graphene oxides (GOs). Three frequencies and three pH conditions were tested (28, 580, and 1000 kHz and 3.5, 7, and 9.5, respectively). Regarding the effects of US frequency and pH, 580 kHz and pH 3.5 were more effective at removing CBZ and DCF (>86% for CBZ and >92% for DCF) than 1000/28 kHz and pH 7/9.5 within 60 min. However, sonocatalytic removal was enhanced in the presence of GOs; more than 99% CBZ and DCF removal was achieved at 580 kHz and pH 3.5 within 40 min. The sonicated GOs were more stable at 28 kHz than at higher frequencies of 580 and 10,00 kHz. The adsorption of CBZ and DCF has increased when GOs were sonicated at 28 kHz (44% and 61%, respectively) compared with 580 kHz (34% and 52%, respectively) and 1000 kHz (18% and 39%, respectively). The negative charges of GOs increased at 28 kHz (-105.1 mV), however, it decreased at higher frequencies such as 580 kHz (-71.5 mV) and 1000 kHz (-58.6 mV), which led to increased electrostatic repulsion that increased the stability of the GO particles in water. The overall enhancement in CBZ and DCF removal was due to an increase in cavitational bubbles, which in turn led to increased production of OH• and enhanced adsorption due to dispersion (resulting from US irradiation), which caused an increase in active adsorption sites of the GOs.


Subject(s)
Carbamazepine/chemistry , Diclofenac/chemistry , Graphite/chemistry , Oxides/chemistry , Sonication/methods , Water Purification/methods , Adsorption
8.
Saudi J Biol Sci ; 25(1): 27-30, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29379352

ABSTRACT

The past decade has proven the competence of nanotechnology in almost all known fields. The evolution of nanotechnology today in the area of the food industry has been largely and has had a lot of contribution in the food processing, food package, and food preservation. The increasing global human population has come with growing population to be fed, and food production is not adjusted to at par with the growing population. This mismatch has shown the real essence of food preservation so that food products can reach to people on a global scale. The introduction of nanotechnology in the food industry has made it easy to transport foods to different parts of the world by extending the shelf-life of most food products. Even with this beneficial aspect of nanotechnology, it has not been proven an entire full-proof measure, and the field is still open to changing technology. It suffices to note that nanotechnology has to a big extent succeed in curbing the extent of food wastage due to food spoilage by the microbial infestation. Nanotechnology has focused on fresh foods, ensuring a healthier food by employing nano-delivery systems in the process. The delivery systems are the ones, which carries the food supplements. However, these are certain sets of regulations that must be followed to tame or control the health related risks of nanotechnology in food industries. This paper outlines the role of nanotechnology at different levels of the food industry including, packaging of food, processing of food and the various preservation techniques all aiming to increase the shelf life of the food products.

9.
J Hazard Mater ; 336: 21-32, 2017 Aug 15.
Article in English | MEDLINE | ID: mdl-28463735

ABSTRACT

In this study, the performances of photocatalytic reactors of the small and scale-up rotating and flat types were evaluated to investigate the treatment of new emerging contaminants such as bisphenol A (BPA), 17α-ethynyl estradiol (EE2), and 17ß-estradiol (E2) that are known as endocrine disrupting compounds (EDCs). In the laboratory tests with the small-scale rotating and flat reactors, the degradation efficiencies of the mixed EDCs were significantly influenced by the change of the hydraulic retention time (HRT). In particular, considering the effective two-dimensional reaction area with light and nanotubular TiO2 (NTT) on a Ti substrate, the rotating reactors showed the more effective performance than the flat reactor because the degradation efficiencies are similar in the small effective area. In addition, the major parameters affecting the photocatalytic activities of the NTT were evaluated for the rotating reactors according to the effects of single and mixed EDCs, the initial concentrations of the EDCs, the UV intensity, and dissolved oxygen. In the extended outdoor tests with the scale-up photocatalytic reactors and NTT, it was confirmed from the four representative demonstrations that an excellent rotating-reactor performance is consistently shown in terms of the degradation of the target pollutants under solar irradiation.


Subject(s)
Benzhydryl Compounds/chemistry , Endocrine Disruptors/chemistry , Estradiol/chemistry , Ethinyl Estradiol/chemistry , Phenols/chemistry , Photolysis , Solar Energy , Water Pollutants, Chemical/chemistry , Water Purification/instrumentation , Catalysis , Microscopy, Electron, Scanning , Titanium/chemistry
10.
Environ Sci Pollut Res Int ; 21(2): 1251-7, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23892615

ABSTRACT

Perchlorate concentrations in rice samples from many different provinces, and correlation with surface water contamination, were investigated in the Republic of Korea. Perchlorate levels in the 51 rice samples purchased from local markets ranged from below the detection limit to 1.79 ± 0.39 µg/kg with a mean level of 0.21 µg/kg and 7 samples collected from the Nakdong River watershed ranged from 0.38 ± 0.1 to 3.23 ± 0.47 µg/kg with a mean level of 0.9 µg/kg. The correlation coefficient between perchlorate levels in rice samples from the Nakdong river watershed and the levels in surface water was estimated to be approximately 0.904 in the 95% confidence interval. These results show that surface water contamination was highly related to the perchlorate pollution of rice in the Republic of Korea.


Subject(s)
Oryza/chemistry , Perchlorates/analysis , Soil Pollutants/analysis , Water Pollutants, Chemical/analysis , Limit of Detection , Republic of Korea , Rivers/chemistry
11.
Water Sci Technol ; 59(11): 2093-9, 2009.
Article in English | MEDLINE | ID: mdl-19494447

ABSTRACT

A lab-scale UCT-type membrane bio-reactor (MBR) was operated for biological nitrogen (N) and phosphorus (P) removal simultaneously. In order to examine biological nutrient removal (BNR) characteristics of MBR, the lab unit was fed with a synthetic strong and weak wastewater. With strong wastewater, a simultaneous removal of N and P was achieved while application of weak wastewater resulted in a decrease of both N and P removal. Recycled nitrate due to the limited organic in weak wastewater operation probably caused a nitrate inhibition in anaerobic zone. In step feed modification with weak wastewater, both N and P removal capability recovered in the system, indicating that the allocation of COD for denitrification at anoxic zone was a key to increase the biological P removal. In addition, the analysis on the specific P uptake rate in anoxic zone demonstrated that denitrifying phosphorus accumulating organism (dPAO) played an important role to remove up to 40% of P along with N. The sludge production characteristics of UCT-type MBR were similar to ordinary activated sludge with BNR capability.


Subject(s)
Bioreactors , Membranes, Artificial , Nitrogen/metabolism , Phosphorus/metabolism , Waste Disposal, Fluid/methods , Water Purification/methods , Oxygen/metabolism , Sewage/analysis
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