Photocatalytic deg radation of environmental pollutants is being up to date for the treatment of contaminated water. In the present study, ZnO/CuO nanomaterials were successfully fabricated by a ...simple sol-gel method and investigate the photo-degradation of rhodamine B (RhB). The synthesized ZnO/CuO nanoparticles were characterized by X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Vis diffuse reflectance spectroscopy (UV-Vis-DRS), thermal analysis (TGA), surface charge, and Fourier transform infrared spectroscopy (FTIR). The photo-degradation of the dye RhB was followed spectroscopically. The overall composition of ZnO/CuO material was found to be wurtzite phase, with particle size of 30 nm, and the Vis light absorption increased with an increase of Cu content. The ZnO/CuO nanomaterials were highly active leading to a photo-degradation of 10 ppm RhB reaching 98% within 180 min at 0.1 g/L catalyst dosage. The change in surface charge after degradation evaluated by ζ potential measurements and the differences in functional vibration group monitored by Fourier transform infrared spectroscopy (FTIR) indicates that the RhB adsorption on the Zn
45
Cu surface was insignificant. And scavenging experiments demonstrate that the RhB degradation by ZnO/CuO nanomaterials involves to some degree hydroxyl radicals.
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•A new polycation PVBTAC-modified ZnO/SiO2 nanocomposite based on rice husk was successfully fabricated.•The optimum conditions for DCF removal using PVBTAC-modified ZnO/SiO2 were ...contact time 90 min, pH 8 and dosage 10 mg/mL.•The maximum adsorption capacity of DCF was 66 mg/g and the removal efficiency was 91.8%.•After four regenerations, the DCF removal using PVBTAC modified ZnO/SiO2 was still greater than 84%.•The E.coli removal was greater than 88 % that was controlled by electrostatic and non-electrostatic interactions.
The present study investigated the adsorptive removal of non-steroidal medication diclofenac (DCF) using polycation, PVBTAC modified zinc oxide/silica nanocomposite (ZnO/SiO2). The ZnO/SiO2 which was fabricated based on nanosilica rice, was examined by XRD, FT-IR, TEM, EDX, and zeta potential measurements. Surface of ZnO/SiO2 was modified by PVBTAC adsorption at pH 9 and 100 mM KCl to reverse the high charge of material. The optimum parameters for DCF removal using PVBTAC-modified ZnO/SiO2 were contact time 90 min, pH 8 and adsorbent dosage 10 mg/mL. The maximum adsorption capacity and the removal efficiency of DCF were found to be 66 mg/g and 91.8%, respectively, while the bacteria Escherichiacoli(E.coli) removal reached greater than 88 %. Adsorption of DCF on PVBTAC-modified ZnO/SiO2 was mainly controlled by electrostatic attraction between anionic DCF molecules and positively charged PVBTAC-modified ZnO/SiO2 surface whereas the E.coli removal was controlled by both electrostatic and non-electrostatic interactions. Adsorption isotherms of DCF on PVBTAC-modified ZnO/SiO2 at different ionic strengths were reasonably represented by a two-step model while adsorption kinetics fitted well with the pseudo-second-order model. After four regenerations of PVBTAC modified ZnO/SiO2, the DCF removal still exceeded 84%. Our materialis agreat performance adsorbent to remove pharmaceutical and bacteria.
In this study, soil-to-plant transfer factor and annual organ equivalent dose due to ingestion of natural radionuclides in 13 popular food crop samples in Ho Chi Minh city, Vietnam were estimated. ...The obtained data show that the radioactive elements transported from soil to plants play an essential role as indicators for the nutritional needs of plant and the ability to accumulate radioisotopes and heavy metal elements for environmental decontamination. It is found that B. alba and C. gigantean is useful for decontamination of high content potassium in soil, otherwise, P. fruticosa and C. gigantean may be used for soil with high concentration of 210Pb and 226Ra. In addition, biological effects of the plant ingestion in human body were assessed. The doses due to ingestion of food crop samples varied from organ to organ, depending on the organotrophic properties of the radionuclides. For examples, equivalent dose for 40K in large intestine is higher than other organs. In contrast, equivalent dose for 238U, 226Ra, 210Pb and 232Th were mostly at bone surface. In general, the obtained dose values of lower than the average value recommended by UNSCEAR for food crop ingestion pose no threat to the public’s health. However, close investigations are needed in the near future.
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•The activity concentration of natural radionuclides in the soil and the food crop samples were found within the radiation safety limitation.•Soil-to-plant transfer factors for radioisotopes in food crops are in the following order: 40K > 210Pb > 232Th > 238U > 226Ra.•The annual organ equivalent doses due to ingestion of food crop samples vary from organ to organ.
The inhibitory properties towards α-glucosidase
and elevation of postprandial glycemia in mice by the saponin constituent from
peel were evaluated for the first time. Three saponins were isolated by ...silica gel and HPLC, identified as stigmasterol glucoside, campesterol glucoside and daucosterol by NMR spectroscopy. Daucosterol presented the highest content and showed the strongest α-glucosidase inhibitory activity with competitive inhibition. Static fluorescence quenching of α-glucosidase was caused by the formation of the daucosterol-α-glucosidase complex, which was mainly derived from hydrogen bonds and van der Waals forces. Daucosterol formed 7 hydrogen bonds with 4 residues of the active site and produced hydrophobic interactions with 3 residues located at the exterior part of the binding pocket. The maltose-loading test results showed that daucosterol inhibited elevation of postprandial glycemia in ddY mice. This suggests that daucosterol from
peel can potentially be used as a food supplement for anti-hyperglycemia.
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•Cellulose aerogel (CA) fabricated from water hyacinth as an ideal green support.•A novel technique for eco-friendly synthesis of nano-Ag/CA catalyst.•Jasminum subtriplinerve Blume ...leaf extract as a reducing agent for nano-Ag synthesis.•Ag/CA performed outstandingly in the catalytic hydrogenation of nitrophenols.•CA enhanced the recovery and reusability of the catalyst.
Water contamination by hazardous aromatic nitro compounds is a serious problem, and reduction in p-nitrophenol (PNP) by combining a catalyst and a reductant has been a topic of intense interest in recent years. Although several methods have been explored for generating effective metal nanoparticle composites, the nano-size makes it challenging to recover after wastewater treatment, thus restricting its practical use. Additionally, the previously described approaches had critical disadvantages, including high material synthesis costs and secondary environmental contamination. Herein, nontoxic and low-cost materials were employed. A novel green technique for the synthesis of silver nanoparticles (AgNPs) decorated on 3D cellulose aerogel (CA) derived from water hyacinth was demonstrated using an aqueous extract ofJasminum subtriplinerve Blumeleaves as a stabilising and reducing agent for high-performance towards PNP reduction in the presence of NaBH4 in an aqueous medium. The as-prepared composites were investigated by powder X-ray diffraction, scanning electron microscopy with energy-dispersive spectroscopy, high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy and Raman spectroscopy. Batch experiments of PNP hydrogenation were conducted to evaluate the catalytic performance. At room temperature, the reaction could be completed in about 10 min using the 1.5Ag/CA2.0 catalyst, with the catalytic activity almost unchanged. Moreover, the structure has no apparent deterioration after five cycles. Strikingly, the 26.15 nm-average size of AgNPs with even distribution on CA correlates with the good kinetic characterisation/feature (k = 0.34 min−1). In particular, the reduction rates of the three isomers of nitrophenol were examined and found to follow the following order: PNP > o-nitrophenol (ONP) > m-nitrophenol (MNP). This study provides some valuable insights into developing easily separated robust green catalysts for heterogeneous catalytic reactions in the environmental remediation field.
•P. pentosaceus exhibited strong halotolerant, resistance to low pH and bile salts•P. pentosaceus showed strong antagonistic activity against Vibrio spp•P. pentosaceus exhibited strong ...autoaggregation and coaggregation activities•P. pentosaceus improved shrimp survival rate as well as weight gain
This study reports the isolation of a potential probiotic lactic acid bacteria (LAB) from fermented Solanum macrocarpon food and evaluates shrimp bacterial pathogens' inhibition. The isolate was determined by identifying the inhibition zone against Vibrio parahaemolyticus with an antagonistic activity of 360 AU/mL. Molecular identification based on 16S rRNA indicated that the isolate belongs to the Pediococcus genus, named as Pediococcus pentosaceus HN10. The isolate exhibited effective inhibitory ability against various pathogenic including antibiotic-resistant Vibrio spp., Escherichia coli ATCC 85922 and Staphylococcus aureus ATCC 25023. P. pentosaceus HN10 showed potential probiotic properties such as strong salt tolerance, low pH and bile salts resistance, autoaggregation and coaggregation activities. P. pentosaceus HN10 was negative for β-hemolytic and amino acid decarboxylase. Antibiotic resistance assay showed that this strain was sensitive to ampicillin and chloramphenicol. P. pentosaceus HN10 expressed strongly antioxidant activity. In vivo challenge to V. parahaemolyticus in shrimp model indicated P. pentosaceus HN10 enhanced survival rate, weight gain as well as reduced the number of Vibrio in shrimp intestine tract. Overall, this study suggests that P. pentosaceus HN10 could be applied as a supplementation feed for shrimp to minimize pathogenic bacteria's negative effect.
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Elephantopus mollis Kunth (EM), which belongs to Asteraceae family, has been used as a folk medicine with diverse therapeutic properties. Previous studies reported that crude extracts of this plant ...could inhibit several cancer cell lines, including breast carcinoma MCF-7, liver carcinoma HepG2, colorectal carcinoma DLD-1, lung carcinoma NCI–H23, etc.
In this study, the anticancer activity and associated molecular mechanism of EM which is distributed in Vietnam were investigated.
The cytotoxicity of various EM extracts was evaluated on different cell lines by MTT assay. In addition, the effects of EM extracts on cell growth, cell morphology, nuclear morphology, caspase-3 activation, and mRNA expression levels of apoptosis-related genes were also examined.
Our results demonstrated that ethyl acetate extract (EM-EA) caused proliferative inhibition and apoptotic induction towards A549 lung cancer cells (IC50 = 18.66 μg/ml, SI = 5.8) and HL60 leukemia cells (IC50 = 7.45 μg/ml, SI = 14.5) while petroleum ether extract (EM-PE) showed high toxicity to HL60 cell line (IC50 = 11.14 μg/ml, SI = 6.7). Notably, Raji lymphoma cells were also affected by these extracts (IC50 < 20 μg/ml, SI > 4), which has not been reported yet. Furthermore, mechanisms of EM extracts were elucidated. The significant downregulation of PCNA mRNA level induced by EM-EA/PE extracts contributed to the cell-growth restraint. EM-EA extract might activate apoptosis in A549 cells through both extrinsic and intrinsic signaling pathways by causing a 1.55-fold increase in BID, 3.65-fold increase in BAK and 3.11-fold decrease in BCL-2 expression level. Meanwhile, with EM-EA-extract treatment, HL60 cells might encounter P53-dependent apoptotic deaths.
The combination of antiproliferation and apoptosis activation contributed to the high efficacy of EM extracts. These findings not only proved the anticancer potential of EM but also provided further insights into the mechanisms of EM extracts.
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Agar is a common component biosynthesized from various marine algae species that is widely applied in various fields including food and pharmaceutical industries. However, the structural composition ...of agar is highly resisted against chemical and biological hydrolysis. Therefore, tremendous research is exploring various pretreatment strategies to break down the intrinsic chemical structural of agar linkage (i.e. neutral agarose and highly sulfated agaropectin) prior for its industrial potential usage. In this research work, a novel agar degrading bacterium was screened and isolated from agriculture soils. Molecular identification using nucleotide sequence of 16 s rRNA region comparison has indicated that the isolate belonged to Priestia genus, and was identified as Priestia megaterium AT7. The maximum enzyme activity was 52.85 ± 1.76 U/mL after 96 h of culture with 5% inoculum size and agitation speed of 180 rpm. Results indicated that the optimal condition for the production of agarose was achieved at pH 7 at 50 °C. The effects of metal ions (e.g. Ca2+, Co2+, Cu2+, Mn2+, Mg2+, Zn2+ and Fe2+) and organic solvents (e.g. acetone, ethanol, methanol, hexane and isopropanol) on enzyme activity were also evaluated. Marine algae hydrolysis evaluation at concentration of 0.1% indicated the enzyme produced reducing sugar of 683.94 ± 26.93 µg/g after 24 h of treatment. It was also found that the highest antioxidant activities obtained after 20 h of treatment was able to achieve 81.76 ± 3.90% at marine algae concentration of 0.1%. The findings obtained from this research work shows the promising application of extracellular agarase to saccharify marine algae for the recovery of value-added bioproducts.
By using radio frequency (RF) sputtering, the
n
–AlInGaN/
p
–Mg-In
x
Ga
1
−x
N heterojunction diodes were successfully fabricated on Pt/TiO
2
/Si(100) substrate by using the cermet targets for
p
...–Mg-doped In
x
Ga
1
−x
N (with
x
= 0, and 0.1) and
n
–Al-doped InGaN. The target for
n
–AlInGaN film had an Al content of 7.5% and In content of 15%, while the target for
p
–In
x
Ga
1
−x
N film had Mg content of 10%. The experimental data indicated that the
n
–AlInGaN film with a smooth surface and a surface roughness of only 1.54 nm was polycrystalline, had a wurtzite crystal structure, and had electrical properties of carrier concentration of 7.26 × 10
16
cm
−
3
and mobility of 70 cm
2
·V
−
1
·s
−
1
at room temperature (RT). By
I–V
tests at RT, the
n
–AlInGaN/
p
–Mg-In
x
Ga
1
−x
N heterojunction diodes displayed a high breakdown voltage beyond 20 V, low leakage current of 8.73 × 10
−9
A at −1 V, and a turn-on voltage of ~2.5 V. Testing with a temperature range of 25–150°C, the leakage current of the
n
–AlInGaN/
p
–Mg-GaN device at a bias of −5 V increased from 1.69 × 10
−7
A at 25°C to 9.88 × 10
−6
A at 150°C. The optimum barrier height and ideality factor of the
n
–AlInGaN/
p
–Mg-InGaN device were found to be 0.57 eV and 5.6 at 25°C, respectively, while these values investigated at 150°C were 0.67 eV and 4.5. In addition, the electrical characteristics of
n
–AlInGaN/
p
–Mg-In
x
Ga
1
−x
N heterodiodes recognized in the thermionic–emission mode at a wide temperature range can be calculated by applying the Cheung and Norde methods.
Graphical abstract
Online reviews play a vital role in providing multidimensional information for tourists. It also has an effect on the ranking and overall score of hotels. As a powerful tool, the Fermatean fuzzy set ...efficiently models dealing with uncertain information. Considering that there is no study using the correlation coefficient in Fermatean fuzzy context to assess the effect of online reviews on ratings and overall score of hotels. Therefore, a correlation coefficient measure is put forward to determine the relationship between two Fermaten fuzzy numbers and then they are utilized to assess the impact of online reviews on ranking and overall rating of hotels. The paper first introduces the TOPSIS–based ranking model using a new distance under Fermatean set. Then, we construct a new correlation coefficient between two Fermatean fuzzy numbers to measure the effect of online reviews with ranking, overall score and score of hotels under given criteria. A case study on TripAdvisor.com is performed to illustrate the proposed operator and model.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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