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The flower of Hibiscus sabdariffa Linn (Malvaceae) is used in food preparation in sauces, jams, juices, jellies, syrups, flavoring, and has some medicinal uses. Most of the bioactivities of H. sabdariffa L. is antioxidant which has a large amount of phenolic compounds. The phytochemical investigation of the ethyl acetate extract from the flowers led to the isolation of five compounds named 1-O-Acetylglycerol (1), 4-Hydroxybenzaldehyde (2), 3-C-(hydroxymethyl)-β-D- erythrofuranoside (3). Their structures were elucidated by 1D-, 2D-NMR spectra as well as by comparison with those reported in the literature.

Miliusa velutina Dun Hook. f. et. Thoms is the rare and native plant, belongs to the Annonaceae family. The isolated compounds in Miliusa genus showed that many function groups and have diverse bioactivities from the ethyl acetate extract of the trunk of Miliusa velutina, three compounds were isolated and determined based on 1D, 2D NMR spectra, MS and combined comparison with references. The three structurally defined compounds are: 4-hydroxybenzoic acid (1), p-coumaric acid (2), 1-O-methyl- -D-glucopyranoside (3). All of three compounds are first known to exist in the Miliusa velutina.

Two new sesquiterpene lactones, laurenolide A (1) and laurenolide B (2), along with six known compounds, palmitic acid (3), (R,R)-hexahydrofarnesyl acetone (4), trans-phytol acetate (5), cholesterol (6), cholesteryl acetate (7), cholesteryl heptadecanoate (8) were isolated from Palisada intermedia. The chemical structures of all compounds were elucidated by 1D and 2D-NMR spectroscopy and HR-ESI-MS analysis as well as compared with data in the literature. The petroleum ether, chloroform, ethyl acetate, methanol extracts and compounds 1, 2 were tested for the inhibition of two cancer cell lines MCF-7, NCI-H460 and they showed weak or none activities.

Bacillus veleznesis RB.EK7 was recently found as a potent rhizobacterial strain for effective management of black pepper root-knot nematodes. This work aimed to produce, purify, and elucidate the chemical structures of antinematode compounds (ANCs). Concerning cost-effectiveness and environmental issues, this study used organic wastes for the bioproduction of ANCs. Among various substrates, shrimp shells powder was the most suitable carbon/nitrogen source to produce ANCs. The fermentation process for enhancement of antinematode activity was investigated. The targeting ANCs were purified from the fermented culture broth, and their structures were elucidated. Two active compounds were thymine (1) and hexahydropyrrolo [1,2-a]pyrazine-1,4-dione (2). Notably, for the first time, these purified compounds showed potential and moderate anti- J2 nematodes and anti-eggs hatching, respectively. The docking study results indicated that the potent antinematode effect of these compounds may be possibly due to the inhibition of the targeting enzyme acetylcholinesterase. The data of this work suggest that organic waste SSP can be potentially reused for the production of thymine and hexahydropyrrolo [1,2-a] pyrazine-1,4-dione with promising use for the management of black pepper nematodes.

Prosthetic joint infections (PJI) and especially tuberculosis (TB) PJI are rare diseases and hard to cure. The effectiveness of treatments for tuberculous PJI still remains a problem. The objective of this research was to indicate the success of two-stage revision replacement and also giving the associated criteria.From 2015 to 2020, five patients with tuberculous PJI were treated with two-stage revision at Cho Ray hospital, Vietnam. We collected the dataset which included demographic data, the interval from the time of joint replacement to reported infection, records of tuberculous PJI, administration of anti-TB medications (duration, months), history of operation(s), duration of follow-up, and specific type(s) of antibiotics loaded in bone cement. The approval for this study was made by the institutional review board from Cho Ray Hospital, Vietnam. We conducted a literature review based on the keywords "PJI" and "TB" on PubMed.Five patients [median age 66 years (range 35-84)] had found tuberculous PJI. The median time from arthroplasty to diagnosis was 19 months (range 4-48). The diagnosis was confirmed by joint aspirates or synovial tissue. Positive PCR was also reported in all cases. The average duration of anti-tuberculosis polytherapy administration was 14.4 months. The operative techniques on five patients included debridement and using spacer loaded with 2 g streptomycin (and 2 g vancomycin if they got a coinfection) for 1 pack of bone cement, and revision arthroplasty. In most cases, the outcome of treatment using two-stage revision replacement was 80%. Overall, the auxiliary bacterial infections were recognized in three patients with tuberculous PJI and Staphylococcus aureus. Streptomycin and vancomycin were loaded in a cement spacer to increase the success rate, and tuberculous PJI was controlled for all patients.Tuberculous PJI can be controlled with two-stage revision replacement with an antibiotic-loaded cement spacer that is molded intraoperatively with custom mold and prolonged anti-tuberculosis treatment in all cases.IV.

Natural condensed tannins (CT) have received great interest due to their vast beneficial bioactivities. Recently, Euonymus laxiflorus, an edible medicinal herb collected in the Central Highlands of Vietnam, was newly recognized as a natural source rich in antioxidant CT. The aim of this study is to scale up extraction and investigate various novel bioactivities of the isolated CT. The screening of the parts used rich in CT, such as heartwood, trunk bark, branch, and the leaves of EL, indicated that the EL trunk bark (ELTB) has the highest CT content. E. laxiflorus CT (ELCT) was extracted with high-level scale from ELTB via several techniques and then was qualified by NMR spectra and HPLC finger printing. A condensed tannin ELBT-3.1.d was isolated and showed its high molecular weight of ≥ 10 kDa and various in vitro bioactivities. ELBT-3.1.d demonstrated high antioxidant capacity (IC50 = 6.11 µg/mL), and potent enzymes inhibition targets in anti-diabetes, especially showing novel potential inhibition against human salivary α-amylase with IC50 value of 3.01 µg/mL. ELBT-3.1.d displayed no anti-NO effect but did show moderate to effective anticancer activities against A549, MCF-7, HepG2, and WiDr. Notably, condensed tannin ELBT-3.1.d displayed no toxicity to normal cells and a novel potential prebiotic effect on Lactobacillus paracasei BCRC14023 and Lactobacillus rhamnosus BCRC16000. In the animal test, ELCT demonstrated significant effect on reducing plasma glucose in mice at the doses of 50–100 mg/kg BW. The current study contributes to enrich the novel bioactivities of ELCT which may be suggested as functional food or drugs due to processing numerous beneficial bioactivities.

From the ethyl acetate extract of the stems of Miliusa velutina, seven compounds (1-7) were isolated, including two new compounds such as mivelutina A acid (1), mivelutina B acid (2) and one known compound mivelutina B methyl ester (3). For this NMR data were not known previously. Their relative structures were elucidated based on NMR spectroscopic analysis. The absolute configuartions were determined based on DFT calculations of 13C chemical shifts. All of the seven compounds were screened for their in vitro cytotoxic activities against HepG2 cell line using the SRB assay. Epoxyconiferyl alcohol (7) showed the highest potential for the cytotoxicity of cancer cell lines HepG2 with the IC50 values of 95.94 μg/mL (527 μM).

Panax vietnamensis (Vietnamese ginseng, Ngoc Linh ginseng) is an endemic Panax species of Vietnam. From the methanol extract of the leaves of Panax vietnamensis, five compounds (1–5) were isolated, including one new sesquiterpene lactone such as panaxolide (1) and four known compounds. The structures of the compounds (1-5) were elucidated by spectral techniques such as 1 D NMR (1H NMR, 13C NMR), 2 D NMR (COSY, HSQC, HMBC, NOESY) and mass spectrometry. The absolute configuration of 1 was determined based on the Cotton effects in the CD spectrum. All of the five compounds were screened for their in vitro growth inhibitory activities against cancerous cells (HepG2) and normal cells (fibroblast) using the SRB assay. Panaxolide (1) showed the highest potential for the growth inhibition of cancerous cells HepG2 with the IC50 values of 63.8 μM.

A new glutinane-triterpenoid, nepetifoliol (

A new glutinane-triterpenoid, nepetifoliol (1), together with two known compounds, dymacrin D (2), and (+)-ar-tumerone (3) were isolated from the n-hexane extract of the aerial parts of Leonotis nepetifolia. Their chemical structures were elucidated by spectroscopic data analysis as well as the comparison of their NMR data with the ones published in the literatures. A putative biosynthetic pathway for the formation of the new compound (anti-diaxial-5,6-diol) (1) from the precursor triterpene glutinol was proposed. Compounds (2), (3) and some previously reported ones, isolated from this extract, including 5α-stigmasta-22-ene-3-one (4), friedelin (5), chrysophanol (6), physcion (7), and 4'-O-methylalpinumisoflavone (8) were evaluated for their α-glucosidase inhibition. Among tested compounds, 3 and 6 showed good activities with their IC50 values of 5.3 ± 0.2 and 4.9 ± 0.3 µg/mL, respectively, comparing to the positive control, acarbose (IC50 127.7 ± 0.2 µg/mL).

This study aimed to establish the culture process for the cost-effective production of prodigiosin (PG) from demineralized crab shell powder (de-CSP), a fishery processing byproduct created via fermentation. Among the tested PG-producing strains, Serratia marcescens TNU02 was demonstrated to be the most active strain. Various ratios of protein/de-CSP were used as the sources of C/N for PG biosynthesis. The PG yield was significantly enhanced when the casein/de-CSP ratio was controlled in the range of 3/7 to 4/6. TNU02 produced PG with a high yield (5100 mg/L) in a 15 L bioreactor system containing 4.5 L of a newly-designed liquid medium containing 1.6% C/N source (protein/de-CSP ratio of 3/7), 0.02% (NH4)2SO4, 0.1% K2HPO4, and an initial pH of 6.15, at 27 &deg, C for 8 h in dark conditions. The red pigment was purified from the culture broth and then quantified as being PG by specific Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) and UV spectra analysis. The purified PG demonstrated moderate antioxidant and effective inhibition against four cancerous cell lines. Notably, this study was the first to report on using crab wastes for PG bioproduction with high-level productivity (5100 mg/L) in a large scale (4.5 L per pilot) in a short period of fermentation time (8 h). The salt compositions, including (NH4)2SO4 and K2HPO4, were also a novel finding for the enhancement of PG yield by S. marcescens in this report.

From the ethyl acetate extract of the stems of

From the ethyl acetate extract of the stems of Miliusa velutina, seven compounds (1–7) were isolated, including two new compounds such as mivelutina A acid (1), mivelutina B acid (2) and one known compound mivelutina B methyl ester (3). For this NMR data were not known previously. Their relative structures were elucidated based on NMR spectroscopic analysis. The absolute configuartions were determined based on DFT calculations of 13C chemical shifts. All of the seven compounds were screened for their in vitro cytotoxic activities against HepG2 cell line using the SRB assay. Epoxyconiferyl alcohol (7) showed the highest potential for the cytotoxicity of cancer cell lines HepG2 with the IC50 values of 95.94 μg/mL (527 μM).

This article deals with the local existence of weak solutions for a wave equation with a nonlinear integral equation at the boundary

From the leaves of Bidens pilosa L., the n-hexane, chloroform, and aqueous extracts exhibited in vitro α-glucosidase inhibitory activity, with IC50 values of 235.8, 125.6, and 100.3 μg/mL, respectively. Two new compounds, methyl 4-O-caffeoyl-2-C-methyl- d -erythronate (1) and 4-O-methylokanin (2), and seven known compounds were isolated from these extracts. The chemical structures of 1–9 were elucidated on the basis of NMR spectroscopic analysis. The caffeoylquinic acid derivatives were isolated from the aqueous extract, and showed significant α-glucosidase inhibitory activity with IC50 values ranging from 10.7 to 74.7 μM.

Eight known compounds and one new compound, a eudesmane-type sesquiterpene (1), were isolated from the leaves of Artemisia vulgaris. Their structures were elucidated by HR-ESI-MS, and NMR analyses.

A robotic near-field antenna measurement system allowing for acquisition over non-canonical measurement surfaces is presented. The robot consists of a six-axis robotic arm and a seventh axis rotary positioner and the created acquisition surface is parametrically reconfigurable. The near-field to far-field transformation required is also described. The success of the technique is demonstrated through measured results, compared to canonical measurement data.

From MeOH-soluble fraction of the flowers of

From MeOH-soluble fraction of the flowers of Hibiscus sabdariffa (Malvaceae), one new lignan, (+)-4-O-methyl-5′-methoxy-secoisolariciresinol (1), together with four known compounds (2–5) were isolated. The structures were elucidated based on NMR spectroscopic analysis. The absolute configuration of 1 was determined based on the Cotton effects in the CD spectrum. Compounds 1, 3 and 4 showed antioxidant activities with the SC50 values of 56.9, 19.3 and 22.7 µM, respectively.

A new dehydrodigallic acid derivative (1), along with 19 known compounds, including 6 phenolic derivatives, 2 steroids and 11 triterpenoids were isolated from the ethanol extract of the root of Geum urbanum. Herein, there is the first report of steroid and triterpene in Geum urbanum. The purified metabolites were characterised by NMR spectroscopic and mass spectrometric analyses. The identification of the known compounds (2–20) was based on the comparison of their NMR spectroscopic features with previously published data. The structural characteristics of compound 1 were elucidated by comprehensive 1D and 2D NMR spectroscopic methods and acid hydrolysis.

Financial integration has greatly contributed to economic growth and development around the globe, in particular for developing countries. However, this process of financial integration has also provided threats in the form of instability which threaten the progress of economic growth and development. The objective of this study is to examine a set of indicators which are valid and indicative of financial instability in the case of developing countries. A panel data of 17 developing countries during the period 2000–2017 is utilized. The credit growth is used as a proxy of financial instability. Standard methods such as the pooled OLS, fixed effect model and random effect model are considered to ensure robustness. Empirical findings from this study indicate that the key determinants of financial instability in developing countries including Vietnam include the GDP growth rate, inflation rate, the growth rate of base money, the change in foreign exchange reserves, lending interest rate, returns in the stock market and the return on equity ratio of the banking sector. Findings from this study appear to support the views of Post-Keynesians in relation to the mechanism leading to financial instability, in particular for developing markets.

From the crude ethanol extract of Wedelia trilobata leaves, hexane and dichloromethane fractions exhibited in vitro antimalarial activity against the Plasmodium falciparum parasite (strain PFB), with IC50 values of 27.0 and 13.0 μg/mL, respectively. Specifically, two new (9R)-eudesman-9,12-olide δ-lactones, wedelolide G (1) and wedelolide H (2), were isolated from the dichloromethane extract and showed IC50 values of 3.42 and 5.96 μM, respectively. Six known compounds are also present in the extract. The structures of 1⿿8 were elucidated through spectroscopic studies.

Two new sesquiterpene lactones, wedelolides A (1) and B (2), were isolated by bioassay-guided fractionation from the leaves of Wedelia trilobata, together with known trilobolides 6-O-isobutyrate (3) and 6-O-methacrylate (4). The compounds 1 and 2 were the first examples of an unprecedented framework: a novel sesquiterpene delta-lactone, (9R)-eudesman-9,12-olide. The structures of the antimalarial wedelolides A (1) and B (2) were determined on the basis of MS and 2D NMR spectral analysis. The absolute configuration of eight carbon stereocenters of compounds 1 and 2 was determined to be 1S,4S,5S,6R,7S,8S,9R,10S by mean of auxiliary chiral MTPA derivatives.

Encapsulation in object oriented models refers to the bundling of data with the methods that operate on that data, it is used to hide the values or state of a structured data objects and preventing unauthorized parties' direct access to them. Access control mechanism in information systems is the process of mediating every request to resources and determining whether the request should be granted or denied. This paper proposes an approach allowing us to integrate access control mechanisms in object oriented paradigm. More detail, we define the access permissions between methods of classes in a UML model and providing a prototype to verify if the program implementation satisfied their access permission constraints.