Herein, a facile strategy to fabricate the novel manganese oxide-imprinted mesoporous carbons (MOPCx, x presents for pyrolysis temperature) was described via the direct pyrolysis of Mn2(BDC)2(DMF)2 ...(BDC = 1,4–benzenedicarboxylate, DMF = N,N–dimethylformamide) as a self-sacrificed template at various temperatures (x = 550, 750, and 950 °C). The characterization results demonstrated the existence of MnO embedded in carbon structures with different morphologies, and enhancing surface areas (249.86–294.67 m2/g) compared with their precursor (3.59 m2/g). For methylene blue adsorption experiments, the MOPC pyrolyzed at 950 °C (MOPC950) revealed the best candidate with maximum uptake capacity (124.1 mg/g), so far higher than other MOPCx and Mn2(BDC)2(DMF)2 materials. Finally, adsorption mechanisms involving H-bond, and π–π interaction were proposed via the chemisorption between surface functional groups (carboxyl, phenol, lactone, and base).
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•Novel MOPCx nanomaterials were facilely synthesized under various temperatures.•Kinetic and isotherm of methylene blue adsorption onto MOPCx were investigated.•Surface functional groups on MOPCx play a crucial role in methylene blue adsorption.•MOPC950 reached the highest Qm value, at 124.1 mg/g.
•Essential oil was extracted from Allium schoenoprasum L. (AS) bulbs from Quang Tri province, Vietnam.•The hydro-distillation process with suitable extracting conditions gave an essential oil yield ...of 0.290 %.•The AS bulb essential oil in xylene contained disulfide and trisulfide compounds as predominant components.•The obtained AS bulb essential oil exhibited high antioxidant and antibacterial activity.
This paper presents a comprehensive investigation on the extraction of essential oil from Allium schoenoprasum L. (AS) bulbs collected in Quang Tri province, Vietnam. Effects of extracting conditions on the quantity of extracted essential oil were investigated, followed by the evaluation of physicochemical characteristics, chemical composition and biological activities. The hydro-distillation process under suitable extracting conditions (extraction time of 3 h, NaCl concentration of 5 %, material-to-NaCl solution ratio of 1:2) allowed obtaining the highest essential oil yield of 0.290 ± 0.003 %. Chemical composition analysis (Quadrupole GC/MS) of the AS bulb essential oil in xylene indicated that disulfide and trisulfide compounds, as major components, accounted for 97.53 % of the identified compounds. The obtained AS bulb essential oil exhibited high antioxidant activity, which is significantly higher than that of ascorbic acid, in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical test. Moreover, it provided strong antibacterial activity against Escherichia coli, methicillin−resistant Staphylococcus aureus, methicillin sensitive Staphylococcus aureus and moderate inhibition activity against carbapenem-resistant Pseudomonas aeruginosa and Streptococcus pneumoniae.
This study aims to determine optimal conditions for extraction of phenolic compounds with maximum antioxidant activity from Vernonia amygdalina Del. leaves using Response Surface Methodology and ...Central Composite Design (RSM-CCD). Results showed that extracting time, temperature and solvent to material ratio had a significant effect on phenolic content (p < 0.001). The interactions between the three factors were also found to be significant at 95% confidence level. The polyphenol content was 137.15 ± 1.36 mg gallic acid /g dry weight (dw), the flavonoid content was 96.78 ± 1.39 mg quercetin/g dw, the total antioxidant activity was 1.95 ± 0.09 mg ascorbic acid/g dw and iron reduction activity was 5.90 ± 0.12 mg FeSO4/g dw at optimum conditions of 34.82 hours at 53.09°C with solvent to material ratio is 43.64 (ml /g). The determination coefficients of all models was greater than 0.995 suggesting that the regression model can represent the experimental data well.
Yen NTN, Chung DD, Hong NTK, Cham NP, Nhan VT, Linh DTL, Ngoc NLB, Thai NM, Nga ND, Anh NT. 2023. Isolation, phylogenetic analysis and bioprospection of myxobacteria from Vietnam. Biodiversitas 24: ...5653-5663. Myxobacteria have been considered microbial factories for producing secondary metabolites that have a variety of potential biological actions for discovering and isolating new biological molecules. Myxobacteria were isolated from soil samples collected in some provinces/cities in Vietnam. The purified isolates were identified based on morphology, biochemical test and phylogenetic analysis inferred from 16S rRNA gene. High-throughput screening assays including 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DDPH) for antioxidant properties and microdilution for antimicrobial activity were performed with myxobacterial extracts. Compounds from potential strain were predicted using liquid chromatography coupled with mass spectrometry. Forty-three myxobacterial strains were isolated and classified into seven genera of Angiococcus, Archangium, Chondromyces, Corallococcus, Cystobacter, Melittangium, and Myxococcus. The extract from CT21 strain had the highest total antioxidant activity (IC50 = 52.34 ± 1.47 and 30.28 ± 0.74 ?g/mL for the DPPH and ABTS, respectively). It is worth noting that all strains isolated myxobacterial strains show inhibitory activity against at least one of the tested microorganisms. The most potent antimicrobial strain was Myxococcus stipitatus GL41, which inhibited all tested microorganisms, and the minimal inhibitory concentration (MIC) values were 1 ?g/mL against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive Staphylococcus aureus (MSSA), Streptococcus faecalis, Candida albicans, and Aspergillus niger. Mass spectrometry analysis revealed the presence of althiomycin - the polyketide antibiotic from ethyl acetate fraction. In the present study, myxobacteria were isolated from soil sample collected from Vietnam, analyzed phylogenetically, and screened for biological activities.
Abstract
Cordyceps militaris
is a valuable medicinal mushroom that has been interested in research by scientists around the world, which has high value in promoting health, immunoregulatory, ...antioxidant, anti-inflammatory and cancer prevention. Following our previous research, the extraction process in pilot scales was built on the results of the project Nguyen Tat Thanh University “Research and propose the process of extracting extracts from
Cordyceps militaris
in Kon Tum province”, which was deployed and accepted in 2020. After evaluating the quality characteristics of raw powder materials, the condition of concentration and preservation of
Cordyceps militaris
extract was conducted. To achieve the required moisture (<20%), it was necessary to concentrate
Cordyceps militaris
extract at three standards: 60°C, 70°C and 80°C in 150 minutes, 120 minutes and 105 minutes, respectively. Considering the three standards, it was found that the cordycepin content at 80°C was statistically significantly lower than the remaining two temperature landmarks. Concentrate the extract at 70°C for 120 minutes to obtain a concentrated extract with cordycepin content of 2938.97 ± 94.66 (µg / g DW) with the moisture content of 8.78 ± 1.95 (%).
Reducing hazardous chemicals in chromatography and improving the fast, safe sample preparation process is the goal of an environmentally friendly and green approach. A fast and specific UPLC-MS/MS ...technique has been developed and validated to simultaneously determine metformin (MET) and glimepiride (GLM) in human plasma. Glipizide was used as an internal standard (IS), and analytes were extracted using the protein precipitation method with acetonitrile containing 0.1% formic acid. Chromatographic separations were performed on the BEH C18 column (1.7 µm, 2.1 mm x 50 mm) and pre-column. Elution was carried out through a gradient program using water and acetonitrile; both added 0.1% formic acid. Tandem mass spectrometry and positive ion-electrospray ionization, and the multiple reaction monitoring modes were used to detect fragment ions of the active ingredients. Precursor ion to fragment ion transitions included 130.0 → 70.9 m/z, 491.3 → 352.1 m/z, and 446.2 → 99.9 m/z for MET, GLM, and IS, respectively. The method was improved and verified in accordance with US Food and Drug Administration guidelines. Linear curves range from 1-100 ng/mL for MET and 0.25-25 ng/mL for GLM. The approach has quantitative limits of 1 ng/mL for MET and 0.25 ng/mL for GLM. The obtained recoveries were higher than 85%, while the coefficient of variation (%CV) was below 15% for all analytes. This study has provided an environmentally friendly solution, and improved sensitivity, and analysis time so it can be used to monitor drug concentration in plasma.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Cordyceps militaris is frequently employed in pharmacology and nutrition for its well-documented health benefits. The advancement of Cordyceps militaris farming technology has facilitated the ...establishment of a reliable supply source capable of effectively meeting the expanding market demand. This study aimed to analyze and compare cordycepin concentrations in the fruiting bodies of Cordyceps militaris cultivated from five raw material sources in Vietnam. The results revealed significant variations in cordycepin concentrations among the samples, with average concentrations (measured in mg/g) as follows: Sample 1 (0.8), Sample 2 (1.2), Sample 3 (0.6), Sample 4 (1.0), and Sample 5 (0.9). Notably, Cordyceps militaris from Sample 2 exhibited the highest cordycepin concentration, while Sample 3 had the lowest. Differences in cordycepin content between Cordyceps militaris samples from different raw material sources may be attributed to variations in manufacturing technology. The results of this study provided the necessary information to evaluate the quality of Cordyceps militaris products on the market and propose quality standards for raw materials in the food and pharmaceutical industries.
Pharmacists play a variety of roles in supporting the health care system. The COVID-19 epidemic originated in China and has spread to many countries around the world. In the context of the current ...COVID-19, additional support from pharmacists' human resources will be needed in the future. This research survey explores the knowledge, attitude, and prevention strategies in Vietnam during the COVID-19 pandemic. This research aims to collect data from Vietnamese students in Ho Chi Minh City's pharmacy sector. The following objectives are to study the awareness of the COVID-19 virus, acts of prevention, risk awareness, and compliance measures to prevent further outbreaks of COVID -19 in Ho Chi Minh City. This cross-sectional survey used anonymous questionnaires that investigated the knowledge, attitudes, and prevention of Vietnamese students' COVID-19 epidemic. The unit of analysis consists of undergraduate pharmacy students from the first year to the last year. Data were collected during April and May 2020. Statistical analysis was performed using SPSS. Pharmacy students in this study were 80% female. The main source of information for pharmacy students to access information about COVID-19 epidemics from websites of the health authorities (31.7%) and news from television and newspapers (40.2 %). The Cronbach alpha coefficients of the three main factors in this study were knowledge (0.74), attitude (0.85), and prevention of COVID-19 (0.89), which show acceptable internal consistency. This research has shown no statistically significant difference between pharmacy students' demographics in three KAP variables, and there is a strong positive correlation between the three factors. It shows the unity and social solidarity of the study participants towards COVID-19. This study shows that pharmacy students have an epidemic concern about COVID-19 today. Pharmacy student's attention knowledge, attitude and preventive COVID-19. Sources of information from television and newspapers are important and updated regularly and accurately about COVID-19 to achieve effectiveness, helping pharmacy students to be aware of COVID- 19 pandemic in the country and the world.