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This study evaluates the phytotoxic potential of methanolic extracts from six Asteraceae species: Wedelia chinensis , Helianthus annuus , Cosmos bipinnatus , Tagetes erecta , Tithonia diversifolia , and Zinnia elegans . The extracts were tested at concentrations of 0.03, 0.1, 0.3, and 1.0 g/mL to assess their inhibitory effects on the radicle and hypocotyl lengths of Echinochloa crus-galli and Echinochloa colona . The two most potent species, C. bipinnatus and T. diversifolia , were further evaluated using extracts from their roots, stems, and leaves. Among these, C. bipinnatus leaf extracts showed the most significant phytotoxicity and were tested at 20, 40, and 60 days of plant age. At 0.03 g/mL, C. bipinnatus extract inhibited the hypocotyl and radicle lengths of E. colona by 23.01% and 56.45%, and E. crus-galli by 8.5% and 36.35%, respectively. At 1.0 g/mL, the extract inhibited the hypocotyl lengths of E. colona and E. crus-galli by 97.54% and 88.15%, and the radicle lengths by 93.52% and 99.99%, respectively. The 60-day-old C. bipinnatus leaf extract exhibited the highest inhibitory effect, correlating with the identification of key allelochemicals such as cinnamic acid, caffeic acid, coumaric acid, ferulic acid, 2-4 dimethohydroxy benzoic acid, and salicylic acid. These findings suggest that the 60-day-old C. bipinnatus leaf extracts have strong potential for use in the biological control of these weed species, offering a promising avenue for the development of natural herbicides., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). Plant‐Environment Interactions published by John Wiley & Sons Ltd and New Phytologist Foundation.)

From the MeOH residue of Barringtonia macrocarpa branches and leaves, one new isoryanodane diterpene, barringisol ( 1 ), and two new isoryanodane diterpene glucosides, barringisosides A and B ( 2 and 3 ), were obtained using various chromatographic isolations. The structural characterization was confirmed by spectroscopic methods including 1D, 2D NMR and HR-ESI-QTOF-MS. This is the first isolation of isoryanodane diterpene derivatives from Barringtonia species. Moreover, the in vitro cytotoxicity of 1 - 3 on three human cancer cell lines (HepG2, LNCaP and MCF7) was also accessed using SRB assays.

Four new acylated oleanane-type triterpene saponins, symplosaponins A-D (1-4) were successfully isolated from the leaves of Symplocos cochinchinensis (Lour.) S. Moore, alongside with five known compounds (5-9), 2-methoxy-4-prop-1-enylphenyl-1-O-β-D-apiofuranosyl-(1 → 6)-β-D-glucopyranoside (5), and 1-[O-β-d-xylopyranosyl-(1 → 6)-O-β-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6), 6-O-p-coumaroylsucrose (7), arillatose B (8), and (-)-secoisolariciresinol-O-β-D-glucopyranoside (9). The structures of these compounds were elucidated through spectroscopic methods, comparison with existing data, and chemical methods. Furthermore, all compounds were assessed for their impact on hepatocellular viability using the Resazurin reduction assay. These investigations aimed to explore the potential hepatoprotective properties of isolated compounds. As a result, 1-[O-β-d-xylopyranosyl-(1 → 6)-O-β-d-glucopyranosyl]-2,6-dimethoxy-4-propenyl-phenol (6) and (-)-secoisolariciresinol-O-β-D-glucopyranoside (9) demonstrated statistically significant hepatoprotective activity in a concentration-dependent manner., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2023. Published by Elsevier B.V.)

Phytochemical studies on Aphanamixis plants have attracted considerable attention over the past few decades due to the structural diversities and significant biological activities of terpenoids produced by these plants. In the present study, five new acyclic diterpene lactone derivatives, aphanamixionolides A-E (1-5), and three known tirucallane-type triterpenes, namely, piscidinol A (6), hispidone (7), and bourjotinolone A (8), were isolated from the leaves of Aphanamixis polystachya . Their structures were elucidated by comprehensive analyses of HR-ESI-MS and NMR spectroscopic data and by comparison with those reported in the literature. Absolute configurations of the new compounds were determined by experimental and TD-DFT calculated ECD spectra. Compounds 1-8 inhibited NO production with IC 50 values of 10.2-37.7 μM, which are comparable to positive control l-NMMA (IC 50 : 31.5 μM)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

This study investigates Symplocos cochinchinensis (Lour.) S. Moore leaves and stems, commonly known as Symplocos, a plant indigenous to Asia renowned for its traditional use in holistic medicine. A comprehensive phytochemical analysis of S. cochinchinensis led to the isolation of two new lignans, namely symplolignans A and B (1 and 2) along with eleven known lignan glucosides: nortrachelogenin 4-O-β-D-glucopyranoside (3), nortracheloside (4), matairesinol 4-O-β-D-glucopyranoside (5), lariciresinol 4'-O-β-D-glucopyranoside (6), balanophonin 4-O-β-D-glucopyranoside (7), dehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside (8), dehydrodiconiferyl alcohol γ'-O-β-D-glucopyranoside (9), 3-(β-D-glucopyranosyloxymethyl)-2-(4-hydroxy-3-methoxyphenyl)-5-(3-hydroxypropyl)-7-methoxy-(2R,3S)-dihydrobenzofura (10), and pinoresinol 4'-O-β-D-glucopyranoside (11). Their chemical structures were elucidated using 1D- and 2D-NMR, mass spectrometry, and their spectroscopic data were compared with those reported in literatures. Furthermore, all compounds were evaluated for their hepatoprotective effects using the Resazurin reduction assay in HepG2 hepatocellular carcinoma cells. Compounds 1, 5, 7, and 8 exhibited notable hepatoprotective efficacy, with cell viability ranging from 105.0±2.6 to 109.2±3.3 at a concentration of 10 μM. This research highlights the therapeutic potential of these compounds and enhanced to the understanding of lignans and neolignans in liver cell proliferation., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

Gross hematuria is one of the most common complications in postrenal transplant patients, accounting for 12% of all renal recipients. The management plan in these cases varies depending on different entities, including infection, renal cell carcinoma, chronic graft rejection, kidney calculus, or recurrence of primary disease. On the other hand, vascular malformation like arteriovenous malformation was less likely to be mentioned due to a lack of consensus in the natural history, pathogenesis, and current management. In this article, we report a 62-year-old man presenting with spontaneous hematuria for a week and 2 days of anuria after 3 years of renal transplantation. Abdominal ultrasound and abdominopelvic computed tomography noted an obstruction of the renal pelvis due to blood clots without signs of vascular injuries. An emergency operation was performed to remove blood clots in the renal pelvis, but after that, hematuria was still recurrence. A digital renal graft subtraction angiography (DSA) revealed an arteriovenous malformation (AVM)in the kidney allograft. This lesion was then successfully selective embolized with glue. Given the high accuracy of DSA, our case highlights the potential role of this imaging modality in diagnosing and treating AVM after failure with other modalities., (© 2024 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Aphanapolystachones A-C (1-3), three undescribed sesquiterpene-diterpene heterodimers, were obtained from the fruits of Aphanamixis polystachya. Their structures and absolute configurations were identified by extensive analysis of HR-ESI-MS, NMR, experimental and TD-DFT calculated ECD spectra. The biosynthetic pathway of them was also proposed, which is produced by key intermolecular Diels-Alder [4 + 2]-cycloaddition reaction between a guaiane sesquiterpene and an acyclic diterpene. Compounds 1-3 inhibited NO production in LPS activated RAW 264.7 cells with the IC 50 values of 1.7 ± 0.2, 3.0 ± 0.3, 5.3 ± 0.3 μM, respectively, lower than that of the positive control L-NMMA (31.5 ± 2.6 μM). In addition, compounds 1-3 significantly reduced IL-6 secretion at diluted concentration of 0.4 μM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Two new glycosides, sindosides A-B (1-2), along with 11 previously identified metabolites (3-13), were isolated from an ethanolic extract of the leaves of Sindora siamensis var. maritima. The structures of the purified phytochemicals were elucidated by interpreting their spectroscopic data (IR, NMR, and HRMS). The absolute configuration of compound 1 was established by experimental and calculated ECD spectra. The antimicrobial results revealed that compound 8 selectively inhibited C. albicans fungal with a MIC value of 64 μg/mL, whereas 11 presented a weak inhibition toward E. faecalis, S. aureus, and B. cereus bacterial strains with the same MIC value of 128 μg/mL. Interestingly, compounds 1, 2, 8, 9, and 11 showed α-glucosidase inhibitory activity with IC 50 values ranging from 14.42 ± 0.21 to 30.62 ± 0.18 μM, which were more active than the positive control (acarbose, with an IC 50 value of 46.78 ± 1.37 μM). Enzyme kinetic analysis revealed that compounds 1, 2, and 11 behaved as uncompetitive inhibitors with K i values of 8.60 ± 1.04, 5.16 ± 0.73, and 7.17 ± 0.98 μM, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Six new acylated flavonoid glycosides namely barringosides J - O (1-6) along with tephrokaempferoside and barringoside D were isolated from the branches and leaves of Barringtonia pendula. The structural elucidation was confirmed by extensive analysis of their spectroscopic data including HRQTOFMS, 1D and 2D NMR experiments. Moderate inhibitory effects on LPS-induced NO production in RAW264.7 cells were observed for barringosides M (4) and N (5) with IC 50 values of 48.40 ± 3.01 and 56.61 ± 3.87 μM, whereas weak inhibition was found for compounds 1-3, 6, and 7 with IC 50 values ranging from 64.91 ± 3.68 to 79.80 ± 3.90 μM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

One new phenylpropanoid glycoside, tinosinen A ( 1 ) and 13 known compounds, tinosinen ( 2 ), citrusin B ( 3 ), picraquassioside C ( 4 ), erythro -guaiacylglycerol- β - O -4'-coniferyl alcohol ( 5 ), erythro -guaiacylglycerol-8- O -4'-(sinapyl alcohol) ether ( 6 ), erythro -syringylglycerol-8- O -4'-(sinapyl alcohol) ether ( 7 ), seco -isolariciresinol 9- O -D- β -glucopyranoside ( 8 ), tinosposide A ( 9 ), pinoresinol-4'- O-β -D-glucopyranoside ( 10 ), syringaresinol-4'- O - β -D-glucopyranoside ( 11 ), pinoresinol ( 12 ), syringaresinol ( 13 ), and lirioresino- β -dimethyl ether ( 14 ) were isolated from the stems of Tinospora sinensis (Lour.) Merr. Their structures were established by detailed spectroscopic studies and comparisons with those reported in the literature. Compound 13 showed significant inhibitory NO production (IC 50 value of 38.53 ± 1.90 μM) in RAW264.7 macrophages, LPS-stimulated. Compounds 3 - 7 , 11 , 12 , and 14 inhibited NO production with IC 50 values ranging from 38.53 to 99.07 μM.

From the fruits of Schisandra cauliflora, five new dimethylbutyrylated dibenzocyclooctadiene lignans, named schisandracaurins A-E, were isolated using separation and chromatographic techniques. Their structures were determined by extensive analyses of HR-ESI-MS, NMR, and ECD spectra. The schisandracaurins A-E potentially inhibited NO production in LPS-activated RAW264.7 cells with their IC 50 values from 21.4 to 30.3 μM., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

We have extensively searched for a cyclic hydrogenated boron molecule that has a three-center two-electron bond at the center. Using first-principles calculations, we discovered a stable molecule of 2:4:6:8:-2H-1,5:1,5-μH-B 8 H 10 and propose its existence. This molecule can be regarded as a building block for sheets of topological hydrogen boride (borophane), which was recently theoretically proposed and experimentally discovered. The electronic structure of the cyclic hydrogenated boron molecule is discussed in comparison with that of cyclic hydrogenated carbon molecules.

Three new chromanes, malloapeltas J-L ( 1 - 3 ), and one new flavone C -glycoside, malloflavoside ( 4 ), together with four known compounds, apigenin 6- C - β -D-xylopyranosyl-8- C - α -L-arabinopyranoside ( 5 ), apigenin 6- C - β -D-glucopyranosyl-8- C - α -L-arabinopyranoside ( 6 ), apigenin 7- O - β -D-apiofuranosyl-(1→2)- β -D-glucopyranoside ( 7 ), and acantrifoside E ( 8 ) were isolated from the methanol extract of the leaves of Mallotus apelta . Their chemical structures were determined using spectroscopic methods, including 1D, 2D NMR, and HR-ESI-MS methods. All the isolated compounds were evaluated their cytotoxic activity against human prostate cancer (PC-3) and human breast cancer (MCF-7) cells, but none of them showed cytotoxicities on both human cancer cell lines.

Repeated column chromatography resulted in the isolation of two new glycosides, miliusides A-B ( 1 and 7 ), along with six known metabolites ( 2 - 6 , and 8 ) from the leaves of Miliusa sinensis Finet and Gagnep. The structures of the purified phytochemicals were elucidated by interpreting their spectroscopic data (NMR, HRMS), as well as comparison with the previous literature. The biological evaluation of acetylcholinesterase (AChE) inhibitory effects and anti-inflammatory activity by measuring nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 mouse macrophage cells, were also conducted. Among them, compounds 5 and 7 exhibited significant AChE inhibitory activities (IC 50 = 53.36 ± 4.20 and 88.50 ± 8.79  µ M, respectively), compared with the positive control (Galanthamine, IC 50 = 1.65 ± 0.15  µ M). Only the MeOH extract showed suppression effects on NO production in LPS-induced RAW264.7 cells (IC 50 = 38.18 ± 3.25  μ g/mL) comparable to that of the positive control, l-NMMA (IC 50 = 2.21 ± 0.56  μ g/mL).

Increasing interest has been paid for hydrogen adsorption on atomically controlled nanoalloys due to their potential applications in catalytic processes and energy storage. In this work, we investigate the interaction of H 2 with small-sized Ag n Cr ( n = 1-12) using density functional theory calculations. It is found that the cluster structures are preserved during the adsorption of H 2 either molecularly or dissociatively. Ag 3 Cr-H 2 , Ag 6 Cr-H 2 , and Ag 9 Cr-H 2 clusters are identified to be relatively more stable from computed binding energies and second-order energy difference. The dissociation of adsorbed H 2 on Ag 2 Cr, Ag 3 Cr, Ag 6 Cr, and Ag 7 Cr clusters is favored both thermodynamically and kinetically. The dissociative adsorption is unlikely to occur because of a considerable energy barrier before reaching the final state for Ag 4 Cr or due to energetic preferences for n = 1, 5, and 8-12 species. Comprehensive analysis shows that the geometric structure of clusters, the relative electronegativity, and the coordination number of the Cr impurity play a decisive role in determining the preferred adsorption configuration., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Five new dibenzocyclooctadiene lignans, named kadsuindutains A-E (1-5), and three known ones schizanrin F (6), schizanrin O (7), and schisantherin J (8) were isolated from the stems of Kadsura induta . Their structures were determined by analyses of HR-ESI-MS, NMR, and ECD spectra. Compounds 1-5 contain a 2',4'-dioxygenated-2',3'-dimethylbutyryl moiety which is rarely reported for dibenzocyclooctadiene lignans. Molecular docking predicted that compounds 1-8 displayed good binding affinity to the active site of iNOS and TNF-α proteins but unstable binding to the active site of COX-2 protein. Additionally, in vitro experiments showed that compounds 1-8 inhibited NO production in LPS-activated RAW264.7 cells with IC 50 values from 10.7 μM to 34.0 μM, compared to the positive control L-NMMA (IC 50 = 31.2 μM)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Three new furostane saponins, ramofurosides A-C (1-3), and two known saponins, fistulosaponin B (4) and (25R)-26-O-β-D-glucopyranosyl-1β,3β,26-trihydroxyfurosta-5,20(22)-diene-1-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (5) were isolated from the methanol extract of Allium ramosum seeds. Their structures were identified based on spectroscopic evidence and comparison with those reported in the literature. All compounds were evaluated for reduction of lipid accumulation in HepG2 cell lines. As a result, compounds 1 and 3 showed a significant reduction in total lipid content by 27.93±3.05 and 27.54±1.68 %, respectively, at a concentration of 100 μM., (© 2022 Wiley-VHCA AG, Zurich, Switzerland.)

Phytochemical investigation of a methanol extract of Panax pseudoginseng flower buds resulted in the isolation of 22 dammarane-type triterpenoid saponins, including three new compounds, pseudoginsenosides A-C ( 1 - 3 ), and 19 known analogs. Their chemical structures were identified by the comprehensive spectroscopic methods, including 1 D and 2 D NMR and mass spectra. In addition, their cytotoxic effects toward three human carcinoma cell lines, including liver (HepG2), breast (MCF7), and lung (A549) were also evaluated.

A theoretical study of geometric and electronic structures, stability and magnetic properties of both neutral and anionic Ge 16 M 0/- clusters with M being a first-row 3d transition metal atom, is performed using quantum chemical approaches. Both the isoelectronic Ge 16 Sc - anion and neutral Ge 16 Ti that have a perfect Frank-Kasper tetrahedral T d shape and an electron shell filled with 68 valence electrons, emerge as magic clusters with an enhanced thermodynamic stability. The latter can be rationalized by the simple Jellium model. Geometric distortions from the Frank-Kasper tetrahedron of Ge 16 M having more or less than 68 valence electrons can be understood by a Jahn-Teller effect. Remarkably, DFT calculations reveal that both neutral Ge 16 Sc and Ge 16 Cu can be considered as superhalogens as their electron affinities (≥3.6 eV) exceed the value of the halogen atoms and even that of icosahedral Al 13 . A detailed view of the magnetic behavior of Ge 16 M 0/- clusters shows that the magnetic moments of the atomic metals remain large even when they are quenched upon doping. When M goes from Sc to Zn, the total spin magnetic moment of Ge 16 M 0/- increases steadily and reaches the maximum value of 3 μ B with M = Mn before decreasing towards the end of the first-row 3d block metals. Furthermore, the IR spectra of some tetrahedral Ge 16 M are also predicted., Competing Interests: There are no conflicts of interest to declare., (This journal is © The Royal Society of Chemistry.)

Two new phenolic glycosides, oroxylumosides A ( 1 ) and B ( 2 ), along with four known compounds darendoside A ( 3 ), leucosceptoside A ( 4 ), acteoside ( 5 ) and decaffeoylacteoside ( 6 ) were isolated from the stem bark of Oroxylum indicum . Their structures were elucidated by extensive analysis of the 1 D and 2 D NMR as well as HR-ESI-QTOF-MS. In addition, compounds 1  -  4 exhibited inhibitory effects on NO production in LPS-stimulated BV2 microglial cell line with IC 50 values of 58.2 ± 2.9, 70.6 ± 3.5, 56.8 ± 2.8 and 61.1 ± 3.1 µM, respectively.

Xylanases (EC 3.2.1.8) have been considered as a potential green solution for the sustainable development of a wide range of industries including pulp and paper, food and beverages, animal feed, pharmaceuticals, and biofuels because they are the key enzymes that degrade the xylosidic linkages of xylan, the major component of the second most abundant raw material worldwide. Therefore, there is a critical need for the industrialized xylanases which must have high specific activity, be tolerant to organic solvent or detergent and be active during a wide range of conditions, such as high temperature and pH. In this study, an extracellular xylanase was purified from the culture broth of Aspergillus niger VTCC 017 for primary structure determination and properties characterization. The successive steps of purification comprised centrifugation, Sephadex G-100 filtration, and DEAE-Sephadex chromatography. The purified xylanase (specific activity reached 6596.79 UI/mg protein) was a monomer with a molecular weight of 37 kDa estimating from SDS electrophoresis. The results of LC/MS suggested that the purified protein is indeed an endo-1,4-β-D-xylanase. The purified xylanase showed the optimal temperature of 55 °C, and pH 6.5 with a stable xylanolytic activity within the temperature range of 45-50 °C, and within the pH range of 5.0-8.0. Most divalent metal cations including Zn 2+ , Fe 2+ , Mg 2+ , Cu 2+ , Mn 2+ showed some inhibition of xylanase activity while the monovalent metal cations such as K + and Ag + exhibited slight stimulating effects on the enzyme activity. The introduction of 10-30% different organic solvents (n-butanol, acetone, isopropanol) and several detergents (Triton X-100, Tween 20, and SDS) slightly reduced the enzyme activity. Moreover, the purified xylanase seemed to be tolerant to methanol and ethanol and was even stimulated by Tween 80. Overall, with these distinctive properties, the putative xylanase could be a successful candidate for numerous industrial uses., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Chemical composition and antioxidant activity of the essential oil of Alseodaphne velutina Chev. (Lauraceae) were investigated for the first time from Viet Nam. Leaf essential oil was hydrodistilled and analysed by GC and GC-MS that totally identified 32 terpenoid compounds (accouting for 89.18% of the total oil) with β-patchoulene (25.74%) and β-caryophyllene (12.81%) as two major sesquiterpene hydrocarbons compounds. The antioxidant potential of leaf essential oil was evaluated using DPPH, ABTS and FRAP assays, and revealed a moderate-to-high activity comparable with already known antioxidant standard Trolox.

Geometrical and electronic structures of the 13-atom clusters Al x Sc y with x + y = 13, as well as their thermodynamic stabilities were investigated using DFT calculations. Both anionic and neutral isomers of Al x Sc y were found to retain an icosahedral shape of both Al 13 and Sc 13 systems in which an Al atom occupies the endohedral central position of the icosahedral cage, irrespective of the number of Al atoms present. Such a phenomenon occurs to maximize the number of stronger Al-Al and Sc-Al bonds instead of the weaker Sc-Sc bonds. NBO analyses were applied to examine their electron configurations and rationalize the large number of open shells and thereby high multiplicities of the mixed clusters having more than three Sc atoms. The SOMOs are the molecular orbitals belonged to the irreducible representations of the symmetry point group of the clusters studied, rather than to the cluster electron shells. Evaluation of the average binding energies showed that the thermodynamic stability of Al x Sc y clusters is insignificantly altered as the number y goes from 0 to 7 and then steadily decreases when y attains the 7-13 range. Increase of the Sc atom number also reduces the electron affinities of the binary Al x Sc y clusters, and thus they gradually lose the superhalogen characteristics with respect to the pure Al 13 ., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Various studies showed that the suppression of α-glucosidase activity can impede the glucose absorption in our body, and therefore, it can be used to treat type 2 diabetes. Hence, the compounds with anti-α-glucosidase have gained considerable attention because of their potential application in diabetes treatment. In previous literature studies, these anti-α-glucosidase compounds were extracted from plants and fungus. Less studies are being conducted to identify the anti-α-glucosidase compounds in the microbial community. In this study, 23 marine bacterial strains were screened for their potential to suppress the α-glucosidase activity. The highest inhibitory activity was exhibited by isolated L06 which was identified as Oceanimonas smirnovii EBL6. The cultivation conditions, such as temperature and pH, were optimized to increase the production of α-glucosidase inhibitors by Oceanimonas smirnovii EBL6 strain. The result findings showed that the highest yield of α-glucosidase inhibitors can be obtained at the culture time of 120 h, fermentation temperature of 30 °C, and pH 4.6. Under these conditions, the inhibitory activity of α-glucosidase can reach 81%. The IC 50 of n-butanol extract was 13.89 μg/ml, while standard acarbose was 31.16 μg/ml. Overall, these findings suggest that Oceanimonas smirnovii produces α-glucosidase inhibitors and could been applied in the biochemical and medicinal fields in the future., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

One new iridoid glycoside ( 1 ), shanzhiside N -L-phenylalanyl ester along with seven known compounds, mussaenoside ( 2 ), shanzhiside methyl ester ( 3 ), barlerin ( 4 ), mussaendodise G ( 5 ), mussaendodise U ( 6 ), mussaendodise P ( 7 ), and mussaglaoside B ( 8 ) have been isolated from Mussaenda pilosissima Valeton. Their chemical structures were elucidated by spectroscopic methods, 1 D-, 2 D-NMR, and mass spectra. Compounds 1-7 showed significant inhibitory activity on LPS-stimulated NO production in BV2 cells with the IC 50 values ranging from 43.5 to 65.2 µM.

Using chromatographic methods, three new dihydrostilbene glycosides, sasastilbosides A-C ( 1 - 3 ) and four known compounds, catechin ( 4 ), rutin ( 5 ), nicotiflorin ( 6 ), and rehmaionoside A ( 7 ) have been isolated from Camellia sasanqua Thunb. Their chemical structures were elucidated by spectroscopic methods (1 D-, 2 D-NMR) and mass spectra. Compounds 1 - 7 were evaluated for α -glucosidase and α -amylase inhibitory effects. Compounds 3 and 4 showed α -glucosidase inhibitory activity with IC 50 values of 77.6 ± 1.6 and 72.4 ± 1.3 μM, respectively. Compound 1 showed α -amylase inhibitory activity with IC 50 value of 53.7 ± 1.6 μM.

Binary clusters of transition-metal and noble-metal elements have been gathering momentum for not only advanced fundamental understanding but also potential as elementary blocks of novel nanostructured materials. In this regard, the geometries, electronic structures, stability, and magnetic properties of Cr-doped Cu n , Ag n , and Au n clusters ( n = 2-20) have been systematically studied by means of density functional theory calculations. It is found that the structural evolutions of CrCu n and CrAg n clusters are identical. The icosahedral CrCu 12 and CrAg 12 are crucial sizes for doped copper and silver species. Small CrAu n clusters prefer the planar geometries, while the larger ones appear as on the way to establish the tetrahedral CrAu 19 . Our results show that while each noble atom contributes one s valence electron to the cluster shell, the number of chromium delocalized electrons is strongly size-dependent. The localization and delocalization behavior of 3d orbitals of the chromium decide how they participate in metallic bonding, stabilize the cluster, and give rise to and eventually quench the spin magnetic moment. Moreover, molecular orbital analysis in combination with a qualitative interpretation using the phenomenological shell model is applied to reveal the complex interplay between geometric structure, electronic structure, and magnetic moment of clusters. The finding results are expected to provide greater insight into how a host material electronic structure influences the geometry, stability, and formation of spin magnetic moments in doped systems., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Two new pregnane glycosides, gyminosides A and B ( 1 and 2 ) and three known, tinctoroside B ( 3 ), tinctoroside C ( 4 ), and gymnepregoside F ( 5 ) were isolated from the leaves of Gymnema inodorum (Lour.) Decne. Their structures were elucidated by physical and chemical methods and comparing with those reported in the literature. All these compounds were evaluated for α -glucosidase assay. Compound 5 exhibited the most anti α -glucosidase activity with inhibitory percentage of 63.7 ± 3.9% at the concentration of 200 μM. Compounds 1 - 4 showed moderate anti α -glucosidase activity with inhibitory percentage ranging from 40.0 to 52.1%.

Background: The association between economic status and kidney disease is incompletely explored even in countries with higher economy (HE); the situation is complex in lower economies (LE) of South Asia and Southeast Asia (SA and SEA)., Methods: Fifteen countries of SA and SEA categorized as HE and LE, represented by the representatives of the national nephrology societies, participated in this questionnaire and interview-based assessment of the impact of economic status on renal care., Results: Average incidence and prevalence of end-stage kidney disease (ESKD) per million population (pmp) are 1.8 times and 3.3 times higher in HE. Hemodialysis is the main renal replacement therapy (RRT) (HE-68%, LE-63%). Funding of dialysis in HE is mainly by state (65%) or insurance bodies (30%); out of pocket expenses (OOPE) are high in LE (41%). Highest cost for hemodialysis is in Brunei and Singapore, and lowest in Myanmar and Nepal. Median number of dialysis machines/1000 ESKD population is 110 in HE and 53 in LE. Average number of machines/dialysis units in HE is 2.7 times higher than LE. The HE countries have 9 times more dialysis centers pmp (median HE-17, LE-02) and 16 times more nephrologist density (median HE-14.8 ppm, LE-0.94 ppm). Dialysis sessions >2/week is frequently followed in HE (84%) and <2/week in LE (64%). "On-demand" hemodialysis (<2 sessions/week) is prevalent in LE. Hemodialysis dropout rates at one year are lower in HE (12.3%; LE 53.4%), death being the major cause (HE-93.6%; LE-43.8%); renal transplants constitute 4% (Brunei) to 39% (Hong Kong) of the RRT in HE. ESKD burden is expected to increase >10% in all the HE countries except Taiwan, 10%-20% in the majority of LE countries., Conclusion: Economic disparity in SA and SEA is reflected by poor dialysis infrastructure and penetration, inadequate manpower, higher OOPE, higher dialysis dropout rates, and lesser renal transplantations in LE countries. Utility of RRT can be improved by state funding and better insurance coverage., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Suceena Alexander et al.)

Sixteen sesquiterpenoids ( 1  -  16 ), including two new compounds namely saussucostusosides A and B ( 1 and 2 ), were isolated from the roots of Saussurea costus by various chromatographic separations. Their structures were elucidated by 1 D and 2 D NMR and HR-QTOF-MS experiments. Among isolated compounds, costunlide ( 6 ), 3 β -[4-hydroxymethacryloyloxy]-8 α -hydroxycostunolide ( 10 ) and 11 β ,13-dihydrozaluzanin C ( 16 ) exhibited potent inhibitory effects on LPS-induced NO production in RAW264.7 cells with IC 50 values of 7.08 ± 0.34, 2.40 ± 0.06 and 5.55 ± 0.24 µM, respectively.

Aim: There is paucity of data on the epidemiology of end-stage kidney disease (ESKD) from South Asia and South-East Asia. The objective of this study was to assess the aetiology, practice patterns and disease burden and growth of ESKD in the region comparing the economies., Methods: The national nephrology societies of the region; responded to the questionnaire; based on latest registries, acceptable community-based studies and society perceptions. The countries in the region were classified into Group 1 (High|higher-middle-income) and Group 2 (lower|lowermiddle income). Student t-test, Mann-Whitney U test and Fisher's exact test were used for comparison., Results: Fifteen countries provided the data. The average incidence of ESKD was estimated at 226.7 per million population (pmp), (Group 1 vs. Group 2, 305.8 vs. 167.8 pmp) and average prevalence at 940.8 pmp (Group 1 vs. Group 2, 1306 vs. 321 pmp). Group 1 countries had a higher incidence and prevalence of ESKD. Diabetes, hypertension and chronic glomerulonephritis were most common causes. The mean age in Group 2 was lower by a decade (Group 1 vs. Group 2-59.45 vs 47.7 years)., Conclusion: Haemodialysis was the most common kidney replacement therapy in both groups and conservative management of ESKD was the second commonest available treatment option within Group 2. The disease burden was expected to grow >20% in 50% of Group 1 countries and 78% of Group 2 countries along with the parallel growth in haemodialysis and peritoneal dialysis., (© 2020 Asian Pacific Society of Nephrology.)

Actinoplanes sp. A1094 strain had been selected for its high production of acarbose from 20 different strains of Actinoplanes sp. can be found in wild. The content for glucosidase inhibitor of acarbose concentration was recorded at 1.12 g/L. The conducted analysis of 16S rRNA sequence of Actinoplanes sp. A1094 showed 99% similar identity to the corresponding sequence of Actinoplanes hulinensis. Acarbose was purified from Actinoplanes hulinensis 1094 with a yield of 8.48%, purity of 98% and further identified by LC/MS and NMR methods (C 25 H 43 NO 18 ; m/z: 645.6 g/mol). The purified acarbose was used to evaluate the hypoglycemia in streptozotocin (STZ)-induced diabetic mice model. The purified acarbose reduced postprandial blood glucose level in comparison with Glucobay® as medication for control type 2 diabetes in a combination therapy. Notably, the outcomes of native acarbose on fasting blood glucose levels in mice resemble akin to the commercial product and the acarbose accumulating fermentation and metabolic engineering from the cell gene in which would reduce in production cost. Therefore, acarbose from Actinoplanes hulinensis 1094 could be potentially used to make products for the treatment of type II diabetes., Competing Interests: Declaration of competing interest The authors declare that they have not known of any competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Mallotusapelta(Lour.) Müll.Arg has been used in traditional medicine for the treatment of chronic hepatitis. Six new chromene derivatives, malloapeltas C-H (1-6) and one known compound, malloapelta B (7) were isolated and structured from the leaves of M.apelta. Two pairs of enantiomers (1a/1b and 2a/2b) were successfully separated by chiral high-pressure liquid chromatography (HPLC). The structures and absolute configurations of compounds were determined using spectroscopic methods, including 1D, 2D NMR, and MS and quantum chemical calculation methods. All compounds were evaluated for cytotoxic activity using cell counting kit-8 (CCK-8) assay against ovariancancer cell line (TOV-21G). Compounds 1-5 and 7 exhibited significant growth and viability inhibitory effects with GI 50 values ranging from 0.06 to 10.39 μM and IC 50 values ranging from 1.62 to 10.42 μM on ovarian cancer cell line, TOV-21G. The most cytotoxic compounds 2, 3, and 7 were chosen for studying in apoptosis mechanism. Compounds 2, 3, and 7-induced apoptosis as evidenced by activated caspase 8, caspase 9, and PARP, increased Bak and Bax, and decreased Bcl-xL and survivin. Moreover, compounds 2, 3, and 7 significantly inhibited the NF-κB signaling pathway. Taken together, our findings propose the potential application of compounds 2, 3, and 7 for treating cancer via modulating NF-κB activity., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Retraction of DOI: 10.1103/PhysRevLett.125.016001.

A pentagonal covalent network consisting of sp^{2} and sp^{3} C atoms has been investigated based on the density functional theory. Our theoretical investigations clarified that the pentagonal covalent network is a metastable three-dimensional carbon allotrope with the Fm3[over ¯]m space group possessing remarkable mechanical properties: relatively high bulk modulus of 381 GPa together with a negative Poisson's ratio of -0.241. Accordingly, the pentagonal covalent network possesses extremely high Young's and shear moduli of 1691 and 1113 GPa, respectively, surpassing those of the diamond. The electronic structure of the pentagonal network is a semiconductor with an indirect band gap of 2.52 eV between L and X points for valence and conduction band edges, respectively, with the relatively small carrier masses.

Objectives: The aim of this study was to understand the natural bacterial hosts of antimicrobial resistance genes (ARGs) and their impact on the processes of evolution, spread and positive selection of acquired ARGs., Methods: Environmental carbapenem-resistant Gram-negative bacteria in Vietnam were screened for based on a One Health approach. Whole-genome sequencing (WGS) and comparative genomic analysis of the isolates were performed. WGS of three carbapenem-resistant Shewanella xiamenensis strains (SxND&#95;W2&#95;2018, SxND&#95;W5&#95;2018 and SxND&#95;W9&#95;2018) isolated from canals in Truc Ninh District and Nghia Hung District, Nam Dinh Province, Vietnam, in 2018 was performed using an Illumina MiniSeq system. ARGs in the draft genome sequences were detected using ResFinder, and comparison of genomic regions was performed using BLASTn and Easyfig., Results: Thebla OXA-48 -like carbapenem-hydrolysing class D β-lactamase genes bla OXA-48 , bla OXA-252 and bla OXA-547 were detected in chromosomal contigs of SxND&#95;W2&#95;2018, SxND&#95;W5&#95;2018 and SxND&#95;W9&#95;2018, respectively. Comparative analysis of the surrounding regions of the bla OXA-48 -like genes, including both 10 kb upstream and 10 kb downstream of the genes, showed that the genomic regions were highly conserved in all three isolates., Conclusion: This study analysed the draft genome sequences of carbapenem-resistantS. xiamenensis strains isolated from a water environment in Vietnam. All of the strains carried bla OXA-48 -like gene variants in their chromosomes. This information will contribute to highlight the evolution of bla OXA-48 family carbapenemase genes in nature and the importance of S. xiamenensis as a natural reservoir of important ARGs in the environment in Vietnam., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Using various chromatographic separations, three new acylated flavonoid glycosides, namely barringosides G-I ( 1 - 3 ), were isolated from the water-soluble extract of Barringtonia racemosa branches and leaves. The structure elucidation was performed by extensive analysis of the 1D and 2D NMR and HR-QTOF-MS data. Of the isolated compounds, barringoside I ( 3 ) showed moderate inhibitory effects on LPS-induced NO production in RAW264.7 cells with an IC 50 of 52.48 ± 1.04 µM.

Hydrogen boride nanosheets (HB sheets) are facilely synthesized via ion-exchange treatment on magnesium diboride (MgB 2 ) in an acetonitrile solution. Optical absorption and fluorescence spectra of HB sheets indicate that their bandgap energy is 2.8 eV. According to first-principles calculations, optical absorption seen at 2.8 eV is assigned to the electron transition between the σ-bonding states of B and H orbitals. In addition, density functional theory (DFT) calculations suggest the other allowed transition from the σ-bonding state of B and H orbitals to the antibonding state with the gap of 3.8 eV. Significant gaseous H 2 release is found to occur only under photoirradiation, which causes the electron transition from the σ-bonding state to the antibonding state even under mild ambient conditions. The amount of H 2 released from the irradiated HB sheets is estimated to be 8 wt%, indicating that the sheets have a high H 2 -storage capacity compared with previously reported metal H 2 -storage materials.

Plasmon gain by core-level electrons or elastic electrons observed in past studies seems to be of no practical value in material characterization, mainly because of their ultralow signal intensities. Nevertheless, in the emission spectra of Au samples, we have observed plasmon gain in secondary electrons. The electrons gain energy from surface plasmons after escaping from the surface and thereby only carry surface-plasmon information in the vacuum above the surface. Because the intensity of the emitted SEs is strong, rivaling that of core-level or elastic electrons, the observed phenomenon has in practice the potential to image directly in space the surface plasmon near but exterior to the metal surface.

Parvovirus B19 (PVB19) has tropism to red blood cell progenitors and can be reactivated after organ transplantation. The aim of study was to describe clinical manifestations, laboratory findings, treatments used, and effectiveness in kidney recipients at Viet Duc hospital. A retrospective descriptive study was performed on 663 kidney recipients who were on regular follow-up from 2000 to 2018. PVB19 was detected by polymerase chain reaction PVB19-DNA. Effectiveness of therapy was assessed by Hemoglobin level. Nine out of 663 kidney recipients (1.4%) were diagnosed with PVB19-associated anemia. Eight of these 9 (89%) were diagnosed within the first 3 months following transplantation. All patients had normoscopic anemia; the average reticulocyte proportion and count were 0.15 ± 0.04% and 0.0039 ± 0.0011T/L, respectively. Graft dysfunction was observed in 4/9 (45%) patients. Treatment included reduction of immunosuppression, intravenous immunoglobulin (IVIG), and blood transfusion. All patients responded well to treatment except 1 (11%), who experienced relapse after using low dose of IVIG. PVB19-associated anemia usually occurred early after transplantation and was associated with very low reticulocyte proportion and count. Actual treatment was effective, but the risk of relapse was present., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Structures of the binary Al n Si m clusters in both neutral and cationic states were investigated using DFT and TD-DFT (B3LYP/6-311+G(d)) and (U)CCSD(T)/cc-pvTZ calculations. Silicon-doped aluminum clusters are characterized by low spin ground states. For small sizes, the Si dopant prefers to be located at vertices having many edges. For larger sizes, the Si atom prefers to be endohedrally doped inside an Al n cage. Relative stability, adiabatic ionization energy and dissociation energies of each cluster size were evaluated. A characteristic of most Si doped Al clusters is the energetic degeneracy of two lowest-lying isomers. Calculated results confirm the high stability of the sizes Al 4 Si 2 , Al 12 Si and Al 11 Si 2 + as "magic" clusters, that exhibit 20 or 40 shell electrons and are thermodynamically more stable as compared to their neighbors. Electronic absorption spectra of isoelectronic magic clusters Al 13 - , Al 12 Si, and Al 11 Si 2 + that have two pronounced bands corresponding to blue and violet lights, have been rationalized by using the electron shell model. The magnetically included ring current density (MICD) analyses suggest that they are also aromatic structures as a result of the "magic" 40 shell electrons., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

Silver (Ag) clusters confined in matrices possess remarkable luminescence properties, but little is known about their structural and electronic properties. We characterized the bright green luminescence of Ag clusters confined in partially exchanged Ag-Linde Type A (LTA) zeolites by means of a combination of x-ray excited optical luminescence-extended x-ray absorption fine structure, time-dependent-density functional theory calculations, and time-resolved spectroscopy. A mixture of tetrahedral Ag 4 (H 2 O) x 2+ ( x = 2 and x = 4) clusters occupies the center of a fraction of the sodalite cages. Their optical properties originate from a confined two-electron superatom quantum system with hybridized Ag and water O orbitals delocalized over the cluster. Upon excitation, one electron of the s-type highest occupied molecular orbital is promoted to the p-type lowest unoccupied molecular orbitals and relaxes through enhanced intersystem crossing into long-lived triplet states., (Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

We investigated the energetics and electronic structure of B 3 N 3 -doped graphene employing density functional theory calculations with the generalized gradient approximation. Our calculations reveal that all of the B 3 N 3 -doped graphene structures are semiconducting, irrespective of the periodicity of the B 3 N 3 embedded into the graphene network. This is in contrast to graphene nanomeshes, which are either semiconductors or metals depending on the mesh arrangement. In B 3 N 3 -doped graphene, the effective masses for both electrons and holes are small. The band gap in the B 3 N 3 -doped graphene networks and the total energy of the B 3 N 3 -doped graphene are inversely proportional to the B 3 N 3 spacing. Furthermore, both properties depend on whether or not the graphene region possesses a Clar structure. In particular, the sheets with a Clar structure exhibit a wider band gap and a slightly lower total energy than those without a Clar structure., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

An investigation on structure, stability, and magnetic properties of singly doped Au 19 M (M=Cr, Mn, and Fe) clusters is carried out by means of density functional theory calculations. The studied clusters prefer forming magnetic versions of the unique tetrahedral Au 20 . Stable sextet Au 19 Cr is identified as the least reactive species and can be qualified as a magnetic superatom. Analysis on cluster electronic structures shows that the competition between localized and delocalized electronic states governs the stability and magnetic properties of Au 19 M clusters.

The conductive properties of polypyrrole chains doped with ClO 4 - or MoO 4 2- anions and the existence of polarons and bipolarons in these doped polypyrrole chains were investigated by performing computational calculations based on density functional theory (DFT). Doping with these anions was found to decrease the band gap of the polypyrrole. Theoretical calculations revealed that changing the type of oxidative agent applied does not affect the conversion of polypyrrole into a conducting polymer, but the conductivity of the doped polypyrrole does depend on the ratio of oxidant to polypyrrole.