Excessive antimicrobial usage and deficiencies in hygiene in meat production systems may result in undesirable human health hazards, such as the presence of antimicrobial drug residues and ...non-typhoidal Salmonella (NTS), including antimicrobial resistant (AMR) NTS. Recently, Vietnam has witnessed the emergence of integrated intensive animal production systems, coexisting with more traditional, locally-sourced wet markets. To date no systematic studies have been carried out to compare health hazards in beef, pork and chicken in different production systems. We aimed to: (1) estimate the prevalence of antimicrobial residues in beef, pork and chicken meat; (2) investigate the prevalence and levels of NTS contamination; and (3) investigate serovar distribution and AMR against critically important antimicrobials by animal species and type of retail (wet market vs. supermarket) in Vietnam. Fresh pork, beef and chicken meat samples (N=357) sourced from wet markets and supermarkets in Ho Chi Minh City (HCMC), Hanoi and Dong Thap were screened for antimicrobial residues by PremiTest, and were further investigated by Charm II. Samples from HCMC (N=113) were cultured using ISO 6579:2002/Amd 1:2007. NTS bacteria were quantified using a minimum probable number (MPN) technique. NTS isolates were assigned to serovar by Multilocus Sequence Typing (MLST), and were investigated for their phenotypic susceptibility against 32 antimicrobials. A total of 26 (7.3%) samples tested positive by PremiTest (9.5% beef, 4.1% pork and 8.4% chicken meat). Sulfonamides, tetracyclines and macrolides were detected by Charm in 3.1%, 2.8% and 2.0% samples, respectively. Overall, meat samples from wet markets had a higher prevalence of residues than those from supermarkets (9.6% vs. 2.6%) (p=0.016). NTS were isolated from 68.4% samples from HCMC. Chicken samples from wet markets had by far the highest NTS counts (median 3.2 logMPN/g). NTS isolates displayed high levels of resistance against quinolones (52.2%) and β-lactams (49.6%), but low levels against 3rd generation cephalosporins (4.4%) and aminoglycosides (0.8%). The highest adjusted prevalence of multidrug resistance (MDR) corresponded to isolates from chicken meat and pork (OR 8.3 and 1.8, respectively) (baseline=beef). S. Kentucky was the most common serovar identified (11 from chicken, 1 from beef) and 91.7% isolates was MDR. 11/12 isolates corresponded to ST198, a worldwide-disseminated multi-resistant NTS clone. We recommend stepping up policy measures to promote responsible antimicrobial use in animal production, as well as awareness about withdrawal periods to limit the hazard of residues in animal products, and improving slaughtering/hygiene procedures to limit cross-contamination with NTS, particularly in poultry wet markets.
•Antimicrobial residues were found in 7.3% meat samples (9.6% in meat from wet markets and 2.6% in meat from supermarkets).•Over two thirds (68.4%) of meat samples were contaminated with non-typhoidal Salmonella; 52.2% of isolates were multidrug resistant.•Chicken meat from wet markets had the highest loads of contamination with non-typhoidal Salmonella (median 3.2logMPN/g in positive samples).•Multidrug resistance was highest in Salmonella from chicken meat, and lowest in beef; the type of retail was not linked to increased resistance.•The most commonly identified serovar was multidrug resistant Salmonella Kentucky ST198, with high levels resistance against β-lactams and quinolones.
The work aims to study the removal of crystal violet (CV) using laterite soil with surface modification by surfactant (SML). Surface modification of laterite soil was conducted by pre-adsorption of ...sodium dodecyl sulfate (SDS) at pH 4 and low ionic strength to enhance removal of CV. The effective conditions for CV removal through adsorption technique using SML were optimized and found to be contact time 60 min, pH 6, adsorbent dosage 5 mg/mL, and 5 mM NaCl as background electrolyte. The highest removal of CV using SML reached to 86.5% under optimum conditions. We used Fourier transform infrared spectroscopy (FT-IR) to evaluate the change of surface vibrational groups of laterite after SDS pre-adsorption and after CV adsorption while the different charged surface was determined by ζ potential measurements. The CV adsorption onto SML increased when increasing ionic strength from 1 to 10 mM. Nevertheless, at high ionic strength, this trend is reversal due to desorption of SDS from laterite surfaces. Adsorption isotherms of CV onto SML at different NaCl concentrations were tried to fit by Langmuir, Freundlich, and a two-step adsorption models. The adsorption kinetics were in good agreement with pseudo-second-order model. The removal efficiency of CV after four regenerations still reached higher than 85%. On the basis of adsorption isotherms, charged surface change by ζ potential and surface modification by FT-IR, we suggest that CV adsorption onto SML was induced by both non-electrostatic and electrostatic interactions. We also demonstrate that SML is a novel, reusable, and low-cost adsorbent for cationic dye removal from aqueous solution.
The silver nanoparticles (AgNPs)/peco fabrics were prepared by immobilization of AgNPs on fabrics in which AgNPs were synthesized by γ-irradiation of the 10mM AgNO3 chitosan solution at the dose of ...17.6kGy. The AgNPs size has been estimated to be about 11nm from TEM image. The AgNPs content onto peco fabrics was of 143±6mg/kg at the initial AgNPs concentration of 100 ppm. The AgNPs colloidal solution was characterized by UV–vis spectroscopy and TEM image. The antibacterial activity of AgNPs/peco fabrics after 60 washings against Staphylococcus aureus and Klebsiella pneumoniae was found to be over 99%. Effects of AgNPs fabics on multidrug-resistant pathogens from the clinical specimens were also tested.
•AgNPs were synthesized by gamma Co-60 irradiation of Ag+/chitosan solution.•AgNPs/peco fabric was prepared by deposition of AgNPs on peco fabric.•AgNPs/peco fabric was tested as wrapper of patient’s bed in hospital.•AgNPs/peco fabric wrapper inhibited the growth of bacterial strains remarkably.
Type 2 diabetes mellitus (T2DM) has been increasing rapidly in Vietnam as well as world-wide. One of the major causes of the condition is low fiber intake. It is difficult to eat large amounts of ...vegetables every day to reach a sufficient amount of fiber but Textured Soybean Protein is rich in fiber. The study aimed to examine the effectiveness of Textured Soybean Protein consumption on T2DM patients. In this randomized controlled trial, 47 T2DM patients were divided into an intervention group (n=24) and a control group (n=23). The intervention group were asked to consume 40 g Textured Soybean Protein in 2 dishes for 4 wk. The control group continued their usual diet. Fasting blood samples were drawn before and after intervention to measure fasting plasma glucose (FPG), fructosamine, low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), total cholesterol (T-C), and triglycerides (TG). A 3-day food record was conducted at 1 wk before (baseline) and at the last week (final) of the intervention period. In the Textured Soybean Protein consumption group, there was a significant decrease in fructosamine (363±86 μmol/L to 347±82 μmol/L, p=0.03), T-C (5.2±0.9 mmol/L to 4.8±0.8 mmol/L, p=0.02) and TG (3.5±2.2 mmol/L to 2.8±2.0 mmol/L, p=0.02). Total energy intake in the two groups did not change significantly. There was a shift in the dietary pattern of the Textured Soybean Protein consumption group; lipid intake showed a significant decrease (p=0.001) and fiber intake increased by 6 g (p<0.001). The consumption of Textured Soybean Protein in the diet could have favorable effects in improving glycemic and lipid concentrations in T2DM patients.
Five new triterpenoid glycosides, named campetelosides A–E (1–5), together with three known compounds, chikusetsusaponin IVa (6), umbellatoside B (7), and silvioside E (8) were isolated from the ...leaves of Camellia petelotii (Merr.) Sealy. Their chemical structures were determined by interpretations of HR‐ESI‐MS and NMR spectra. In addition, compounds 1–8 were evaluated for their α‐glucosidase inhibitory effects. Compounds 1–3 significantly showed α‐glucosidase inhibitory activity with IC50 values of 166.7±6.0, 45.9±2.6, and 395.3±10.5 μM, respectively, compared to that of the positive control, acarbose, with an IC50 value of 200.4±10.5 μM.
A new isopropyl chromone (1) and a new flavanone glucoside (2) together with eleven known compounds (3–13) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their ...structures were elucidated as 5,7‐dihydroxy‐2‐isopropyl‐6,8‐dimethyl‐4H‐chromen‐4‐one (1), 5,7‐dihydroxyflavanone 7‐O‐β‐D‐(6′′‐O‐galloylglucopyranoside) (2), strobopinin (3), demethoxymatteucinol (4), pinocembrin‐7‐O‐β‐D‐glucopyranoside (5), (2S)‐hydroxynaringenin‐7‐O‐β‐D‐glucopyranoside (6), afzelin (7), quercetin (8), kaplanin (9), endoperoxide G3 (10), grasshopper (11), vomifoliol (12), litseagermacrane (13) by the analysis of HR‐ESI‐MS, NMR, and CD spectral data. Compounds 1, 2, 5, 6 and 10 inhibited NO production on LPS‐activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, NG‐monomethyl‐L‐arginine acetate (L‐NMMA) with an IC50 value of 32.50±1.00 μM.
•New tactic to develop β-Bi2O3 nanoflakes by slow annealing of BiOI nanoflakes.•β-Bi2O3/PbS has been established to form an inverted p-n nanoheterojunction.•The charge transfer ability of β-Bi2O3/PbS ...in Na2SO4 electrolyte is the highest.
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The nanostructural β-Bi2O3/PbS n-p heterojunction is fabricated using a simple two-step process; electrodeposition of BiOI followed by annealing to form β-Bi2O3 and then PbS deposition by successive ionic layer adsorption and reaction (SILAR) method. The β-Bi2O3 nanoflakes are vertically grown on the substrate while PbS nanoparticles are deposited on Bi2O3. The formation of β-Bi2O3/PbS heterojunction was confirmed by various physical and chemical characterizations. The formation of the np heterojunction at the interface of β-Bi2O3/PbS doubled the photoelectrochemical current density compared with that of the bare β-Bi2O3 nanoflakes. The enhanced photoelectrochemical performance of the heterojunction photoanode structures are scrutinized.
•A facile manufacturing process of new Rb2CO3-decorated In2O3 sensor.•The Rb2CO3/In2O3 composite sensor detecting 100 ppb level NO2 gas at room temperature under visible light illumination.•Propose ...the mechanism for the high sensing performance realized by high rate of electron supply to the receptor.•Good sensing performance of high selectivity, stability, repeatability, linearity, with discussion of the humidity effect.
The Rb2CO3-decorated In2O3 sensor is prepared for detection of NO2 at room temperature under light irradiation. Physical and chemical properties of the materials and structures are thoroughly investigated by various analytical tools of scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy, thereby confirming the formation of the Rb2CO3/In2O3 p-n junction at the interface. The Rb2CO3-decoration effect on In2O3 sensor is examined under light irradiation of different wavelengths and intensities. Rb2CO3-decoration exhibits much higher sensing performance than pure In2O3 sensor, and furthermore, the visible light irradiation improves in the response level and sensing kinetics. The sensor detects less than 100 ppb NO2. In addition, the Rb2CO3-decorated In2O3 sensor shows high selectivity, stability, repeatability, and linearity. The ultimate performance of the nanostructured sensor is elucidated by the depletion model of the conduction type gas sensors. The effect of humidity on the sensing performance is also investigated.
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