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Three new p-coumaroyl flavone glycosides, named fissibicosides A–C (1-3), together with four known flavone glycosides kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranoside (4), kaempferol 3-O-α-apiofuranosyl-(1→2)-β-galactopyranoside (5), kaempferol 3-O-α-L-rhamnopyranoside (6), and quercetin 3-O-α-L-rhamnopyranoside (7) were isolated from the leaves of Fissistigma bicolor. Their structures were determined by HR-ESI-MS, 1D and 2D NMR spectroscopic methods. Compounds 1-7 inhibited the NO productions in LPS stimulated RAW264.7 cells with IC50 values ranging from 54.5 ± 5.8–78.8 ± 5.9 μM.

Objectives: Infectious diseases caused by bacteria are a leading cause of death worldwide. Hence, the objectives of the study are aimed to evaluate the antibacterial activity against five human pathogenic bacteria of methanolic extracts from 66 plants collected from Vietnam. Methods: The broth microdilution method was used to determine the minimum inhibitory concentration (MIC) of methanol extracts of 66 plant species against five bacterial strains. Results: In this study, all the plant extracts were active against at least one train with MIC values ranging from 24 to 2048 μg/mL. Twenty-five plant extracts were active against all three Gram-positive bacteria (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus). Of these, the extracts of Macaranga trichocarpa (Rchb. f. and Zoll.) Mull. Arg. (Euphorbiaceae), Calophyllum inophyllum L. (Clusiaceae) and Caryodaphnopsis baviensis (Lecomte) Airy Shaw (Lauraceae) exhibited the highest antibacterial activity (MIC =24–128 μg/mL), followed by extracts of Betula alnoides Buch.- Ham. e × . D. Don (Betulaceae), Acronychia pedunculata (L.) Miq. (Rutaceae), Croton alpinus A. Chev. ex Gagnep. (Euphorbiaceae) (MIC =64–256 μg/mL). Furthermore, the extract of Rhus chinensis Mill. (Anacardiaceae) and Annona reticulata L. (Annonaceae) exhibited potent antibacterial activity against the two Bacillus species (MIC =32–64 μg/mL). Conclusion: Results of this study reveal that plant extracts from Vietnam have highly antibacterial activity against Gram-positive bacteria. These results suggest that Vietnamese plant extracts may be a rich source of antibacterial drugs.

Two new compounds, schisandrulata A (1) and schisandrulata B (5), and nine known compounds, 6-O-benzoylgomisin O (2), kadsutherin (3), γ-schizandrin (4), pinotatol (6), schisphentetralone A (7), (–)-8′-epi-aristotetralone (8), (–)-8,8′-epi-aristotetralone (9), rel-(8R,8′R)-dimethyl-(7S,7′R)-bis(3,4-methylenedioxyphenyl)tetrahydrofuran (10) and (-)-machilusin (11) were isolated from the leaves of Schisandra perulata Gagnep. Their chemical structures were determined by means of HR-ESI-MS, NMR, and CD spectra. All the compounds were evaluated for their cytotoxic activity against the human oral cancer (CAL27) and human breast cancer (MDA-MB231) cell lines. Compounds 1, 4, 7, and 9 showed potent cytotoxic activity against CAL27 cell line with IC50 values of 1.8 ± 0.2, 1.2 ± 0.1, 1.2 ± 0.2, and 2.0 ± 0.1 μM, respectively, indicating that they have stronger cytotoxic activity than that of the positive control capecitabine (IC50 value of 8.20 ± 0.75 μM). Similarly, compounds 1, 4, 7, and 9 also exhibited potent activity against the MDA-MB231 cell line with IC50 values of 3.5 ± 0.1, 1.80 ± 0.2, 0.9 ± 0.2, and 3.4 ± 0.3 μM, respectively. These results indicated that compounds 1, 4, 7, and 9 could be potential anticancer reagents for further drug discovery research.

Two new norlignans, pouzolignan N (1) and pouzolignan O (2), together with five known norlignans, pouzolignan F (3), pouzolignan G (4), pouzolignan H (5), pouzolignan L (6), and gnetifolin F (7) were isolated from the aerial parts of Pouzolzia sanguinea (Blume) Merr. Their chemical structures were elucidated via HR-ESI-MS and NMR spectroscopic methods. Absolute configurations at stereocenters were confirmed by comparisons of CD spectra with those of TD-DFT calculations. Compounds 1–6 exhibited chemical structures unique to Pouzolzia species. At a concentration of 30 µM, compounds 1–7 exhibited weak cytotoxic activity toward CAL27 and MDA-MB-231 cell lines (cell viability from 65.3 ± 0.86 to 98.8 ± 1.23%). They also inhibited anoctamin-1 activity with inhibitory rates from 8.1 ± 0.87 to 24.3 ± 1.41%.

Using various chromatographic methods, two new sucrose esters, karensucrose A (1) and karensucrose B (2), one new xanthone, karenxanthone (7) along with eight known compounds, 3-(E)-3,4,5-trimethoxycinnamoyl-6′-benzoylsucrose (3), tricornose B (4), glomeratose C (5), tenuifoliside C (6), 1,7-dihydroxyxanthone (8), 1-methoxy-7-hydroxyxanthone (9), 1,7-dimethoxy-6-hydroxyxanthone (10), and wubangziside B (11) were isolated from the roots of Polygala karensium Kurz (Polygalaceae). Their chemical structures were elucidated using spectroscopic and chemical methods and compared with the reported literature. All isolated compounds were evaluated for cytotoxic activity against two human cancer cell lines, human breast cancer (MCF7) and human prostate cancer (PC3) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Mitoxantrone was used as a positive control with IC50 values of 9.7 ± 1.2 μM (MCF7) and 7.4 ± 1.3 μM (PC3). As the results, compound 8 showed cytotoxic activity on MCF7 and PC3 cancer cell lines with IC50 values of 26.2 ± 2.1 and 22.1 ± 1.7 μM, respectively.

Ten triterpenoid glycosides including two undescribed compounds (1 and 2) were isolated from the methanol extract of Allium ascalonicum rhizomes. These compounds were structurally elucidated to be 3β-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl-19α-hydroxyolean-12-ene-28-oic acid 28-O-[α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranosyl] ester (1), 3-O-β-D-glucopyranosyl-(1→3)-[α-L-rhamnopyranosyl-(1→2)]-α-L-arabinopyranosyl-3β,19α-dihydroxyoleanane-12-en-28-oic acid (2), lactifoloside C (3), lactifoloside H (4), randiasaponin IV (5), kudinoside G (6), ilexkudinoside W (7), lactifoloside G (8), kudinoside D (9), and ilexkudinoside T (10) by analyzing their HR-ESI-MS, NMR spectral data and by comparison with those reported in the literature. Compounds 1–10 were evaluated for anoctamin-1 (ANO1) inhibitory activity using yellow fluorescent protein reduction assays. At the concentration of 30 µM, compounds 2 and 9 displayed moderate ANO1 inhibitory percentages of 28.9 ± 0.85% and 26.2 ± 0.65%, respectively.

Extensive phytochemical investigation of Schisandra sphenanthera leaves resulted in the isolation of six highly oxygenated nortriterpenoids (1���6) and five lignans (7���11) including a new pre-schisanartane-type, schisandrathera A (1), a new dibenzocyclooctadiene glycoside, schisandrathera B (7) and two new lignans, schisandrathera C (8) and schisandrathera D (9). Their chemical structures including absolute configurations were determined extensively by means of HR-ESI-MS, NMR, and ECD spectra. In addition, all isolated compounds were tested for cytotoxic activity against PC3 (prostate cancer) and MCF7 (breast cancer) cell lines. Among these compounds, schirubrisin B (3) showed strong cytotoxic effect on both PC3 and MCF7 cell lines with IC50 values of 3.21 �� 0.68, 13.30 �� 0.68 ��M, respectively, whereas ten remaining compounds were found to be less effective in the investigated models.

A new muurolane-type sesquiterpene, a new flavone arabinofuranoside derivative, and other five known flavone arabinofuranoside derivatives were isolated from the leaves of

Three new muurolane type sesquiterpene glycosides, named balanoindicosides A − C (1 − 3), were isolated from the whole plant of Balanophora fungosa subsp. indica using various chromatographic methods. Their structures were determined by extensive analysis of HR-ESI-MS and NMR spectroscopy. The stereochemistry of muurolane sesquiterpene backbone was demonstrated by NOESY analysis. Configuration of C-12 in compounds 2 and 3 could be distinguished by chemical shift value of C-14. Compounds 1-3 exhibited weak cytotoxic activity towards HepG-2, HL-60, LU-1, and MCF-7 cell lines.

A new muurolane-type sesquiterpene, a new flavone arabinofuranoside derivative, and other five known flavone arabinofuranoside derivatives were isolated from the leaves of Fissistigma bicolor (Annonaceae family). Their chemical structures were determined to be (1S,6R,7S)-muurola-4,10(14)-diene-15-ol (1), quercetin 3-O-β-D-apiofuranosyl-(1→2)-α-L-arabinofuranoside (2), quercetin 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranoside (3), quercetin 3-O-α-L-arabinofuranoside (4), kaempferol 3-O-β-D-apiofuranosyl-(1→2)-α-L-arabinofuranoside (5), kaempferol 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinofuranoside (6), and kaempferol 3-O-α-L-arabinofuranoside (7) by analyses of HR-ESI-MS and NMR spectral data. Compounds 4 and 7 containing monosaccharide, arabinofuranoside, potentially inhibited NO productions in LPS activated RAW264.7 cells (IC50 13.4 ± 0.5 and 12.6 ± 0.4 µM) in compared to disaccharide derivatives (IC50 ranging from 58.9 ± 3.3 to 65.6 ± 3.8 µM).

Two new norlignans, pouzolignan N (

Photostability of the polymer solar cells (PSCs) remains a challenge to attain, as number of factors including the electron transport layers contribute to the degradation of PSCs when they are tested under 1 sun illumination, along with heat and humidity. Especially electron transport layers (ETLs) have considerable contribution to the overall degradations in these solar cells. Most studied ETL into the fabrication of inverted PSCs is zinc oxide (ZnO) yet the photostability of these PSCs is limited. This degradation most probably occurred due to the direct contact of zinc metal with the photoactive layer. This interface between ZnO and photoactive layer results in the initiation of degradations in PSCs. Keeping in view of this issue, we have modified the ZnO ETL by mixing ZnO nano particles with ethoxylated polyethyleneimine (PEIE) and then passivating this modified ZnO (m-ZnO) with ultrathin PEIE buffer layer. The power conversion efficiency is not affected by this approach, but when PSCs were subjected to 1 sun illumination, these m-ZnO/PEIE based PSCs have shown the enhanced light soaking (LS) stability. These findings indicate that optimizing the interface between the photoactive layer and the electron transport layer can lead to enhanced LS stability.

Four new pregnane glycosides, gymlatifosides A - D (

Ten triterpenoid glycosides including two undescribed compounds (

Four new pregnane glycosides, gymlatifosides A - D (1 − 4) and one known pregnane glycoside, verticilloside J (5) were isolated from the leaves of Gymnema latifolium Wall. ex Wight. Their chemical structures were elucidated on the basis of extensive spectroscopic methods, including 1D, 2D NMR, HR-ESI-MS, and in comparison with the reported data. All these compounds were tested for α-glucosidase and α-amylase inhibitory activities. Compound 5 exhibited the most anti α-glucosidase activity with inhibitory percentage of 37.8 ± 1.5% at the concentration of 200 μM. Compounds 1–4 showed moderate anti α-glucosidase activity with inhibitory percentage ranging from 7.0 to 30.1%. In addition, all compounds 1–5 showed moderate/weak anti α-amylase activity in the investigated test.

Extensive phytochemical investigation of

Three new triterpene saponins including two lupane-types and an ursane-type were isolated from the leaves of

Two new pregnane glycosides, gyminosides A and B (

Three new muurolane type sesquiterpene glycosides, named balanoindicosides A - C (

Truxinic acid sucrose diesters analogs possess interesting chemical structure by the presence of cyclobutane-ring and macrocyclic sucrose diesters moieties which are rarely found from natural sources. This paper describes the isolation and structural elucidation of four new sucrose diesters of substituted truxinic acids, trigohonbanosides A-D (1–4), from the leaves of Trigonostemon honbaensis. Their chemical structures were elucidated by HR-ESI-MS, NMR, and CD spectroscopic methods. At a concentration of 30 µM, compounds 1–4 moderately inhibited ANO-1 activity with inhibitory percentages of 27.7 ± 1.10%, 35.6 ± 0.92%, 43.7 ± 1.61%, and 40.8 ± 1.25%, respectively.

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%.

Two new steroidal alkaloid saponins, solanigrosides Q and R (1 and 2), together with four known compounds khasianine (3), solamargine (4), solasonine (5), and soladulcoside A (6) were isolated from the whole plants of Solanum nigrum. The structures of new compounds (1 and 2) were determined by interpretation of HR-ESI-MS, 1D and 2D NMR spectra, and chemical transformation. Compound 4 exhibited potent cytotoxic activity against MDA-MB-231, A549, Hep3B, PC3 human cancer cell lines with IC50 values of 1.86 ± 0.45, 2.24 ± 0.15, 0.78 ± 0.11, 5.13 ± 1.34 μM, respectively.

Suite au rattachement de Ha Tay en 200B, la province de Hanoï possède plus de terres agricoles, mais leur vitesse de réduction est plus rapide. Les systèmes de production agricole durable dans l'agriculture périurbaine de Hanoï doivent être soutenus par les rôles multifonctionnels de l'agriculture : approvisionner la ville en aliments sûrs, créer des emplois, assurer des services environnementaux pour les zones urbaines tels que le tourisme et la ceinture verte, gérer l'eau et garantir sa consommation... Cependant, l'absence de gestion institutionnelle appropriée et le manque d'investissements logistiques font que les systèmes périurbains actuels ne sont pas durables. Les enquêtes quantitatives montrent que la durabilité des systèmes de production agricoles reste faible. L.:article conclut que Hanoï devrait se doter de stratégies et politiques de développement de production et d'approvisionnement alimentaires durables, au travers d'investissements logistiques et d'une gestion de la qualité intégrée dans les chaînes de valeur. Il est nécessaire de donner la priorité au développement de circuits de distribution courts et de promouvoir l'émergence de nouveaux villages agricoles planifiés. Une planification régionale détaillée de l'agriculture est essentielle pour mieux comprendre les avantages et les inconvénients des différents types d'agriculture périurbaine qui coexistent à Hanoï aujourd'hui.