Methodology was developed to expand the range of benign alkyl glycoside surfactants to include also anionic types. This was demonstrated possible through conversion of the glycoside to its carboxyl ...derivative. Specifically, octyl β-D-glucopyranoside (OG) was oxidised to the corresponding uronic acid (octyl β-D-glucopyranoside uronic acid, OG-COOH) using the catalyst system
T. versicolor
laccase/2,2,6,6-tetramethylpiperidinyloxy (TEMPO) and oxygen from air as oxidant. The effects of oxygen supply methodology, concentrations of laccase, TEMPO and OG as well as reaction temperature were evaluated. At 10 mM substrate concentration, the substrate was almost quantitatively converted into product, and even at a substrate concentration of 60 mM, 85% conversion was reached within 24 h. The surfactant properties of OG-COOH were markedly dependent on pH. Foaming was only observed at low pH, while no foam was formed at pH values above 5.0. Thus, OG-COOH can be an attractive low-foaming surfactant, for example for cleaning applications and emulsification, in a wide pH range (pH 1.5–10.0).
•The laccase/TEMPO oxidation of dodecyl maltoside and hexadecyl maltoside produced diacids with high yields.•The structure and distribution of the products were determined.•The effect of TEMPO and ...laccase concentration on yield and chain degradation was studied.
Alkyl glycosides with long hydrophobic chains have attractive surfactant properties, but their wider application is hampered by their low solubility in water. Here, a route to increased solubility by introduction of carboxyl groups via laccase/TEMPO oxidation is presented. The oxidation pathways for dodecyl β-maltoside and hexadecyl β-maltoside were studied in detail. Close to full conversion was achieved for both substrates and conditions were found under which the diacid products dominated, with only minor amounts of under-oxidized and over-oxidized products. Dodecyl β-maltoside oxidation was improved to give a yield of 85 % of the diacid derivative. Interestingly, in spite of low substrate solubility the oxidation of hexadecyl β-maltoside was very efficient in aqueous medium, due to the higher solubility of the products. Addition of organic cosolvents did not provide additional advantages. The method is promising for producing soluble anionic derivatives of alkyl glycosides in an environmentally friendly and efficient way.
Modification of alkyl glycosides, to alter their properties and widen the scope of potential applications, is of considerable interest. Here, we report the synthesis of new anionic alkyl glycosides ...with long carbohydrate chains, using two different approaches: laccase/2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) oxidation of a long‐carbohydrate‐chain alkyl glycoside and cyclodextrin glucanotransferase (CGTase)‐catalyzed elongation of anionic alkyl glycosides. The laccase/TEMPO oxidation of dodecyl β‐
d‐maltooctaoside proceeded efficiently with the formation of aldehyde and acid products. However, depolymerization occurred to a large extent, limiting the product yield and purity. On the other hand, CGTase‐catalyzed coupling/disproportionation reactions with α‐cyclodextrin and dodecyl β‐
d‐maltoside diuronic acid (DDM‐2COOH) or octyl β‐
d‐glucuronic acid (OG‐COOH) as substrates gave high conversions, especially when the CGTase Toruzyme was used. It was found that pH had a strong influence on both the enzyme activity and the acceptor specificity. With non‐ionic substrates (dodecyl β‐
d‐maltoside and octyl β‐
d‐glucoside), Toruzyme exhibited high catalytic activity at pH 5–6, but for the acidic substrates (DDM‐2COOH and OG‐COOH) the activity was highest at pH 4. This is most likely due to the enzyme favoring the protonated forms of DDM‐2COOH and OG‐COOH, which exist at lower pH (pKa about 3).
Alkyl glycoside surfactants having long carbohydrate groups including carboxyl groups were synthesized. The carboxyl groups were introduced by chemoenzymatic oxidation and the elongation of the carbohydrate groups was achieved using cyclodextrin glucanotransferase (CGTase) as catalyst. The ability of the CGTase to accept carboxyl containing substrates was studied both experimentally and using molecular modelling.
The COVID-19 (COronaVIrus Disease) pandemic has been spreading globally and social isolation has been implemented as an effective solution to limit the spread of the pandemic before vaccines are ...developed successfully. The reduction of human activities during social isolation is leading to an improvement in air quality being observed worldwide. In this study, we analysed satellite TROPOMI (TROPOspheric Monitoring Instrument) NO
2
(Nitrogen Dioxide) and OMI (Ozone Monitoring Instrument) NO
2
products obtained from Sentinel-5P and Aura satellites, respectively, during the social isolation from 1 April 2020 to 22 April 2020 in Vietnam where air pollution is a serious environmental issue. Both TROPOMI and OMI NO
2
have shown low agreement with local on-ground NO
2
concentration (the correlation coefficient r equals 0.4 and 0.3 in 2020, respectively) but have had moderate correlation with each other in 2020 (r equals 0.81 for two annual averaged maps). In addition, the moderate available data ratio over cloudy northern areas were observed, especially for TROPOMI datasets. During social isolation, the national average NO
2
decreased by 9.3% for TROPOMI and 7.2% for OMI, respectively, in comparison with the same periods in the previous years. The reduction was stronger in the North than in the South and lasted for one more month after the lockdown period. The decrease of NO
2
density during the lockdown was observed strongly in urban areas associated with dense population, traffic density, and industrial zones. Further analysis of NO
2
density for Ho Chi Minh city revealed a decreasing trend of NO
2
during social isolation (16.62% and 11.77% compared with the previous month and the same period in 2019, respectively). Furthermore, we used a random forest model to estimate the NO
2
density (normal life situations) based on daily meteorological data at station. During social isolation, NO
2
density observed in Ho Chi Minh city decreased by 26% down to that of normal life situations. The NO
2
reduction has shown strong anthropogenic impact on air pollution over the study area. Besides, the first use of TROPOMI and OMI NO
2
products together has highlighted potentials of satellite observation for air quality monitoring and analysis in Vietnam where on-ground measurements are very limited.
Two new xanthones, oblongixanthones I (1) and J (2), and seven known compounds (3-9), were isolated from an EtOAc extract of the twigs of Garcinia oblongifolia. Their structures were elucidated using ...spectroscopic methods, mainly 1 D and 2 D NMR. The antidiabetic effects of the two new compounds were evaluated using α-glucosidase and PTP1B inhibition assays. Both compounds displayed strong inhibition towards α-glucosidase with IC
50
values of 258.7 ± 49.3 and 187.1 ± 27.5 μM, respectively (compared with acarbose, IC
50
= 900.0 ± 3.0 μM) and moderate effects against PTP1B with IC
50
values of 93.9 ± 12.3 and 64.1 ± 5.8 μM, respectively (compared with RK682, IC
50
= 4.4 ± 0.3 l μM).
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•Nitrification was successfully activated by salt tolerant bacteria (STB).•STB enhanced COD and TKN removal by 11% and 23%.•The produced NO2–-N and NO3–-N was co-fitted with the ...logistic function.•Free ammonia and high C/N ratio reduced the nitrite oxidation when using STB.
Conventional biological treatment has been reported to be ineffective for pollutant removal in tannery wastewater due to high salinity. To overcome it, this work used salt-tolerant bacteria (STB) isolated from a membrane bioreactor to evaluate the organic and nutrient removal through a series of batch experiments. Compared with the control, the STB reactor enhanced the reduction of persistent organics by 11% based on the double exponential decay model. Besides, the removal of NH4+-N is 26% higher, satisfying the first-order decay model. The nitrification was inhibited entirely in control during 48 h, whilst the assimilation process involved 55% of total nitrogen removal. In the STB reactor, nitrification occurred after 12 h, resulting in significantly increased NO2–-N and NO3–-N concentrations according to the logistic function. Although nitrification was successfully activated, C/N ratios and free ammonia were identified as limiting factors for STB activity, requiring mitigation strategies in further studies.
Objective: Major depressive disorder (MDD) is the second-most prevalent mental health condition in Vietnam. This study aims to validate the Vietnamese versions of the self-reported and ...clinician-rated Quick Inventory of Depressive Symptomatology (QIDS-SR and QIDS-C, respectively) and the Patient Health Questionnaire (PHQ-9), and to assess the correlations between the QIDS-SR, QIDS-C, and PHQ-9.
Methods: 506 participants with MDD (mean age, 46.3 years; 55.5% women) were assessed using the Structured Clinical Interview for DSM-5. The internal consistency, diagnostic efficiency, and concurrent validity of the Vietnamese versions of QIDS-SR, QIDS-C, and PHQ-9 were determined using the Cronbach's alpha, receiver operating characteristic curve, and Pearson correlation coefficient, respectively.
Results: The Vietnamese versions of QIDS-SR, QIDS-C, and PHQ-9 demonstrated acceptable validity, with an area under the receiver operating characteristic curve of 0.901, 0.967, and 0.864, respectively. Sensitivity and specificity, respectively, were 87.8% and 77.8% for QIDS-SR and 97.6% and 86.2% for QIDS-C at the cut-off score of 6, and were 82.9% and 70.1% for PHQ-9 at the cut-off score of 4. Cronbach's alphas for QIDS-SR, QIDS-C, and PHQ-9 were 0.709, 0.813, and 0.745, respectively. The PHQ-9 highly correlated with the QIDS-SR (r = 0.77, p < 0.001) and the QIDS-C (r = 0.75, p < 0.001).
Conclusion: The Vietnamese versions of the QIDS-SR, QIDS-C, and PHQ-9 are valid and reliable tools for screening of MDD in primary healthcare settings.
Two new rocaglamides, 8b-O-5-oxohexylrocaglaol (1) and elaeagnin (2), together with twelve known compounds, were isolated from the bark of Aglaia elaeagnoidea and the whole tree of A. odorata. Their ...structures were determined using spectroscopic methods, mainly 1D and 2D NMR. Cytotoxic activity against HepG2 human liver cancer cells of the isolated compounds was evaluated in vitro using the SRB assay. Three rocaglamide derivatives, dehydroaglaiastatin (13), 8b-O-5-oxohexylrocaglaol (1) and rocaglaol (5), exhibited significant effects with IC
50
values of 0.69, 4.77 and 7.37 µM, respectively.
Background. Streptococcus suis infection is an emerging zoonosis in Asia. We determined the detailed epidemiological, clinical, and microbiological characteristics of S. suis meningitis in adults. ...Methods. We prospectively studied 450 patients with suspected bacterial meningitis. Four hundred thirty-five (96.7%) of the patients participated in a trial to determine the effect of adjunctive dexamethasone treatment. For patients with S. suis infection, bacterial DNA load at hospital admission and during treatment was analyzed in cerebrospinal fluid specimens using quantitative real-time polymerase chain reaction. S. suis strains were characterized using pulsed-field gel electrophoresis and multilocus sequence typing. Putative virulence factors, including extracellular protein factor, suilysin, and muramidase released protein, were detected using polymerase chain reaction and Western blot assay. Predictors of outcome were identified using logistic regression analysis. Results. S. suis was the most common pathogen and was detected in 151 (33.6%) of the patients. Fifty (33.1%) of these 151 patients reported exposure to pigs or pork. Mortality was low (2.6%; 4 of 151 patients died), but mild to severe hearing loss occurred in 93 (66.4%) of 140 patients. Severe deafness at hospital discharge was associated with age >50 years (odds ratio, 3.65; 95% confidence interval, 1.15–11.6), a strain carrying the epf gene (odds ratio, 3.42; 95% confidence interval, 1.02–11.4), and dexamethasone therapy (odds ratio, 0.23; 95% confidence interval, 0.06–0.78) but was not associated with cerebrospinal fluid bacterial DNA load. Bacterial DNA was still detectable in 58 (63%) of 92 cerebrospinal fluid samples after 6–10 days of antimicrobial treatment. Ninety-one of 92 S. suis strains had serotype 2. Thirty-three (36%) of these epidemiologically unrelated strains belonged to 1 pulsed-field gel electrophoresis cluster of multilocus sequence type 1, indicating clonal spread. Conclusion. S. suis serotype 2 is the most frequent cause of bacterial meningitis in adults in southern Vietnam and is associated with substantial morbidity attributable to hearing loss.
Medication errors significantly compromise patient safety in emergency departments. Although previous studies have investigated the prevalence of these errors in this setting, results have varied ...widely.
The aim was to report pooled data on the prevalence and severity of medication errors in emergency departments, as well as the proportion of patients affected by these errors.
Systematic searches were conducted in Embase, PubMed, and the Cochrane Library from database inception until June 2023. Studies provided numerical data on medication errors within emergency departments were eligible for inclusion. Random-effects meta-analysis was employed to pool the prevalence of medication errors, the proportion of patients experiencing these errors, and the error severity levels. Heterogeneity among studies was assessed using the I
statistic and Cochran's Q test.
Twenty-four studies met the inclusion criteria. The meta-analysis gave a pooled prevalence of medication errors in emergency departments of 22.6% (95% Confidence Interval CI 19.2-25.9%, I
= 99.9%, p < 0.001). The estimated proportion of patients experiencing medication errors was 36.3% (95% CI 28.3-44.3%, I
= 99.8%, p < 0.001). Of these errors, 42.6% (95% CI 5.0-80.1%) were potentially harmful but not life-threatening, while no-harm errors accounted for 57.3% (95% CI 14.1-100.0%).
The prevalence of medication errors, particularly those potentially harmful, underscores potential safety issues in emergency departments. It is imperative to develop and implement effective interventions aimed at reducing medication errors and enhancing patient safety in this setting.
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