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Tecoma stans (L.) Juss. Ex Kunth is widely used in folk medicine. In ethnomedicine, it is applied as a cardioprotective, hepatoprotective, antiarthritic, antinociceptive, anti-inflammatory, and antimicrobial. The aqueous extract is considered antidiabetic, and is used as a traditional remedy in Mexico. More than 120 chemical constituents have been identified in its leaves, barks, and roots. However, less is known about the phytochemical properties of T. stans flower extracts. The herbal plant Nervilia concolor (Blume) Schltr. is native to Vietnam, and is used in traditional Chinese medicine to treat diseases such as bronchitis, stomatitis, acute pneumonia, and laryngitis. Only two previous reports have addressed the chemical content of this plant. Bouea macrophylla Griff., commonly known as marian plum or plum mango, is a tropical plant that is used to treat a range of illnesses. Phytochemical analysis of B. macrophylla suggests the presence of volatile components and flavonoids. However, existing data have been obtained from screening without isolation. As part of our ongoing search for alpha-glucosidase inhibitors from Vietnamese medicinal plants, we conducted bioactive-guided isolation of the whole plant N. concolor, the flowers of T. stans, and the leaves of B. macrophylla. We isolated and structurally elucidated five known compounds from T. stans: ursolic acid (TS1), 3-oxours-12-en-28-oic acid (TS2), chrysoeriol (TS3), ferulic acid (TS4), and tecomine (TS5). Three known compounds were isolated from Nervilia concolor: astragalin (NC1), isoquercitrin (NC2), and caffeic acid (NC3). From B. macrophylla, betullinic acid (BM1), methyl gallate (BM2), and 3-O-galloyl gallic acid methyl ester (BM3) were isolated. All compounds showed promising alpha-glucosidase inhibition, with IC50 values ranging from 1.4 to 143.3 µM. The kinetics of enzyme inhibition showed BM3 to be a competitive-type inhibitor. An in silico molecular docking model confirmed that compounds NC1, NC2, and BM3 were potential inhibitors of the α-glucosidase enzyme. Molecular dynamics simulations were carried out with compound BM3 demonstrating the best docking model during simulation up to 100 ns to explore the stability of the complex ligand–protein.

One new cycloartane-type triterpenoid, named 24-epimarkhacanasin C (1), together with four known flavonoids, apigenin (2), luteolin (3), apigenin 7-O-β-D-glucopyranoside (4), and luteolin 7-O-β-Dglucopyranoside (5), was isolated by various chromatographic methods from the ethyl acetate extract of Markhamia stipulata var. canaense leaves. Their structures were elucidated by IR, UV, HR-ESI-MS, and NMR experiments. All compounds were reported for the first time from this species. Their cytotoxicities were evaluated against human breast cancer cell line (MCF-7) by SRB assay. The isolated compounds 1, 3, and 4 exhibited significant cytotoxic activity (IC50 ranged from 53.38 to 68.32 μg/mL), while compounds 2 and 5 did not show activity.

The study aims to determine the hepatoprotective effect of n-hexane, ethyl acetate, and methanol extracts of the leaves and stems of two Cleome species against carbon tetrachloride- (CCl4-) induced liver toxicity both in vitro using human hepatoma (HepG2) cells and in vivo in rats as well as the hepatoprotective property of all isolated compounds on HepG2. After 72 h of treatment, at the concentrations of 25, 50, and 100 μg/mL, the methanol of C. chelidonii stems (CCSM) ranged from 18.6% to 20.8%, whereas the methanol of C. chelidonii stems (CVSM) increased from 12.3% to 17.2% cell viability. The results show that CCSM and CVSM significantly expressed in vitro hepaprotective activity on HepG2. Therefore, the animals were daily treated with these extracts at the doses of 15, 30, and 45 mg/kg body weight for 5 days, and CCl4 was injected (2 ml/kg body weight, i.p.) on the 2nd and 3rd days. Levels of aspartate aminotransferase (ALT) and alanine aminotransferase (AST) in the blood were measured and compared to the silymarin control. The treatments with CCSM and CVSM (30, and 45 mg/kg) possessed significant hepatoprotection and were comparable with the activity of silymarin. Further, phytochemical studies of these ones were conducted and led to the identification of eight flavonoids: visconoside A (1), visconoside B (2), quercetin 3-O-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (3), kaempferol 3-O-β-D-glucopyranoside 7-O-α-L-rhamnopyranoside (4), cleomeside A (5), cleomeside B (6), cleomeside C (7), and quercetin-3-O-[β-D-glucopyranosyl-(1⟶2)]-α-L-rhamnopyranoside 7-O-α-L-rhamnopyranoside (8). Two major flavonoids (1 and 4) displayed significant hepatoprotective property (at the concentration of 100 μM, the prevention percentage values were 66.5% and 74.2%, respectively, compared to the quercetin control, with value of 80.3%).

A new diterpenoid, phyllane C (1), along with three known compounds, ovoideal E (2), spruceanol (3), and fluacinoid B (4) were isolated from the leaves of Phyllanthus acidus growing in Thailand. The structures were determined by analysis of their MS and NMR data as well as by comparison with literature values. DFT-NMR chemical shift calculations and subsequent DP4/DP4+ probability methods were applied to define the relative configuration of 1. Compound 3 showed a weak cytotoxicity against K562 cell line (IC50 41.9 ± 2.31 µg/mL).

From the Vietnamese plant Macrosolen tricolor (Lecomte) Danser, one new diarylpropanoid, named macrotricolorin A (1) together with three diarylheptanoids including bisdemethoxycurcumin (2), demethoxycurcumin (3) and curcumin (4), were isolated. Their structures were elucidated by intensive analyses of their IR, UV, HR-ESI-MS and NMR (1 D & 2 D) spectra. It is the first time that diarylalkanoids have been reported from the genus Macrosolen. Compound 1 exhibited anti-inflammatory activity against the nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW264.7 with an IC50 value of 27.54 ± 1.75 μM.

The study reports a versatile, cost-efficient and ecofriendly protocol for the synthesis of biogenic silver nanoparticles (AgNPs) using the aqueous extracts of Quao Binh Chau, Stereospermum binhchauensis and Che Vang, Jasminum subtriplinerve and their application in antibacterial activity and catalysis. The AgNPs with varying morphology and physical properties have been optimized using the absorption measurements. The biogenic AgNPs have been characterized by Fourier transform infrared spectroscopy, UV–Vis spectroscopy, transmission electron microscopy, X-ray diffraction analysis, energy-dispersive X-ray spectroscopy and thermal behaviors. Stable crystalline AgNPs with average particle sizes of 20.0 nm and 8.0 nm were fabricated from aqueous extract of Quao Binh Chau and Che Vang, respectively. The phytochemicals from the extracts involved in reduction and stabilization of AgNPs are identified by FTIR spectra and thermal gravimetric analysis. Both the biosynthesized AgNPs show the potent antibacterial activity against four tested bacterial strains including Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Agrobacterium tumefaciens. High catalytic activity of the biogenic AgNPs in the degradation of toxic contaminants (4-nitrophenol and methyl orange) was observed. The antibacterial and catalytic activities are found to be size and phytochemical dependent. The antibacterial and catalytic activities of the biogenic nanoparticles would find applications in the biomedical and environmental fields.

A new labdane-type diterpenoid, named vitexnegundin (1), along with seven known compounds, including vitexilactone (2), vitetrifolin D (3), 13-hydroxy-5(10),14-halimadien-6-one (4), (rel 3S,5S,8R,9R,10S)-3,9-dihydroxy-13(14)-labden-16,15-olide (5), artemetin (6), vitexcarpin (7) and penduletin (8), were isolated from the leaves of Vitex negundo L. Their structures were elucidated by using spectroscopic methods, X-ray crystallographic analysis and comparison with those reported in the literature. Moreover, all isolated compounds 1–8 were evaluated for their antimicrobial activity against ESBL-producing Escherichia coli strain and methicillin-resistant Staphylococcus aureus.

Two new cycloartanes, combretanones G and H (1 and 2), were isolated from the leaves of Combretum quadrangulare. Their structures were elucidated by applying a set of spectroscopic methods, while their relative configurations were determined using DFT-NMR chemical shift calculations and subsequent assignment of DP4 probabilities. Compounds 1 and 2 are C-23/C-24 stereoisomers of the previously-reported euphonerin E. Both exhibited moderate cytotoxicity against three human cancer cell lines. Compound 2 was shown to be a potent antiparasitic. Our results confirm the traditional medicinal uses of Combretum quadrangulare in Vietnam.

Bioactive-guided phytochemical investigation of Euphorbia antiquorum L. growing in Vietnam led to the isolation of five ent-atisanes, one seco-ent-atisane, and one lathyrane (ingol-type). The structures were elucidated as ent-1α,3α,16β,17-tetrahydroxyatisane (1), ethyl ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylate (2), ent-atisane-3-oxo-16β,17-acetonide (3), ent-3α-acetoxy-16β,17-dihydroxyatisane (4), ent-16β,17-dihydroxyatisane-3-one (5), calliterpenone (6), and ingol 12-acetate (7). Their chemical structures were unambiguously determined by analysis of one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) and high resolution mass spectrometry, as well as by comparison with literature data. Among them, 1 is a new compound while 2 is an ethylated artifact of ent-3,4-seco-4,16β,17-trihydroxyatisane-3-carboxylic acid, a new compound. Isolates were evaluated for alpha-glucosidase inhibition. Compound 3 showed the most significant inhibitory activity against alpha-glucosidase with an IC50 value of 69.62 µM. Further study on mechanism underlying yeast alpha-glucosidase inhibition indicated that 3 could retard the enzyme function by noncompetitive.

From the leaves of Sterculia foetida L., one new oleanane-type triterpenoid, named stercufoetin A (1) together with four known ones, vergatic acid (2), β-amyrin (3), oleanolic acid (4) and maslinic acid (5) were purified by diversely chromatographic methods. Their structures were proposed by HR-APCI-MS and NMR experiments. Compounds (2–5) were notified for the first time from this species. Compound 1 showed weak cytotoxic effect against three human cancer cell lines (MCF-7, HepG2 and HeLa) using SRB assay.

For the first time, the cytotoxic and phytochemical investigation of the leaves of Stereospermum binhchauensis V.S. Dang, a new species discovered in Viet Nam were finalized and led to purify nine compounds, including one furancoumarin (1), one chromone (3), two triterpenoids (2, 4), two flavonoids (5, 8), two flavanoids (6, 7) and one iridoid (9) using various chromatography methods. Their structures were verified by HR-ESI-MS, NMR experiments and compared with previous literatures. For the first time, compounds (5–8) were realized from the genus Stereospermum, while compounds (1, 2, 3, 4 & 9) were designated from the species S. binhchauensis. Furthermore, the furancoumarin, chromone and flavanoid classes were notified for the first time from the genus Stereospermum.

One new hopane-type triterpene, indicuen (1), along with eight known compounds (2���9) were isolated from the n-hexane extract of the lichen Parmotrema indicum Hale. The chemical structures of isolated compounds were identified by interpretation of their spectroscopic data (1D, 2D NMR and HRESIMS) combined with DFT-NMR chemical shift calculations and subsequent assignment of DP4+ probabilities and by comparison with the literature. Indicuen represents for a rare hopane bearing a 1-carboxyethyl substituent at C-21 in lichens. Compounds 1���3 and 5���8 were evaluated for ��-glucosidase inhibition and cytotoxicity against K562 and HepG2 cancer cell lines. Compounds 1, 5 and 7 exhibited moderate ��-glucosidase inhibition with IC50 values of 201.1, 156.3 and 187.4 ��M, respectively. Compound 1 also showed weak cytotoxicity toward K562 cell line while others showed no activity.

Chemical investigation of the lichen Parmotrema indicum Hale led to the isolation of one new diphenyl ether, parmetherine D (1), along with eight known compounds (2-9). The structures were determined by analysis of MS and NMR data and by comparison with the literature. Compounds 1, 2, and 7 were evaluated for α-glucosidase inhibition. Only compound 1 exhibited significant inhibition.

One new cycloartane-type triterpenoid, named macrobidoupoic acid A (as an C-24 epimeric mixture, 4a, 4 b), together with three known ones (1-3), were clarified by different chromatography from the M. bidoupensis whole plants. Triterpenoids (1, 3 & 4) were detected for the first time from the Macrosolen genus. Chemical structures of them were illuminated using HR-ESI-MS, and NMR (1 D & 2 D) assessments. The cytotoxic properties of triterpenoids (3 & 4) were examined against two human cancer cell lines (A549, and RD) by MTT assay. As results shown, triterpenoids (3 & 4) possessed moderate cytotoxic activity against A549 and RD cancer cells (IC50 ranged from 5.44 to 39.52 μM).

From the most cytotoxic fraction of the ethyl acetate extract of Markhamia stipulata var. canaense V.S. Dang leaves, two new cycloartane-type triterpenoids, named Markhacanasin A (1) and Markhacanasin B (2); were isolated by various chromatographic methods Their structures were elucidated by IR, UV, HR-ESI–MS, NMR (1D & 2D) experiments. The cytotoxicity of two new compounds against five human cancer cell lines (HeLa, HepG2, MCF-7, Jurkat and NCI-H460) were evaluated by SRB assay. As results, 1 exhibited significant cytotoxic activity against all cancer cell lines (IC50 ranged from 14.72 to 29.55 μM) while 2 did not show activity.

Further phytochemical investigation on P. tsavoense led to one new meta-depsidone, parmosidone K together with one known compound, barbatic acid. Their structures were determined by 1D and 2D NMR analysis, high resolution mass spectroscopy, and comparison their NMR data with those reported in literatures. Parmosidone K was evaluated for α-glucosidase inhibition and revealed the powerful activity with IC50 value of 3.12 µM.

From the leaves of Ricinus communis Linn., one new alkaloid, named ricicomin A (1) together with three known ones, ricinine (2), N-demethylricinine (3) and 4-[2-formyl-5-(methoxymethyl)-1H-pyrrol-1-yl]butanoic acid (4) were justified by repeated chromatographic methods. Their structures were determined by comprehensive IR, HR-ESI-MS and NMR analyses. Compound 4 was identified for the first time from the genus Ricinus. DFT-NMR chemical shift calculations and subsequent DP4+ probability methods were applied to confirm the chemical structure of 1. Compounds 1–3 did not display cytotoxic effect against three human cancer cell lines (MCF-7, HepG2 and HeLa) using SRB assay.

Two new cycloartane glycosides, nervisides I&ndash, J, were isolated from Nervilia concolor whole plants. Their structures were unambiguously established by interpretation of their HRESIMS and 1D and 2D NMR data. These cycloartanes comprised a stereogenic center at C-24, the R configuration of which was assigned based on DFT-NMR calculations and the subsequent DP4 probability score. These compounds were tested for cytotoxicity against K562 and MCF-7 tumor cell lines, revealing mild cytotoxic activity.

From the leaves of Cleome viscosa L., two new flavonol glycosides, named visconoside A (1) and visconoside B (2), together with six known flavonol glycosides, vincetoxicoside A (3), vincetoxicoside B (4), kaempferitrin (5), kaempferide 3-O-β- d -glucopyranoside 7-O-α- l -rhamnopyranoside (6), kaempferol 3-O-β- d -glucopyranoside 7-O-α- l -rhamnopyranoside (7), and isorhamnetin 3-O-β- d -glucopyranoside (8) were isolated by various chromatography methods. Its chemical structure was elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and compared with literatures.

This study presents an efficient and facile method for the trapping of Ag+ ions on hybrid nanocomposite based on 2-hydroxypropyl-β-cyclodextrin (HPCD) and alginate (Alg) in aqueous medium through ionotropic gelation mechanism and followed by in situ assembly of silver nanoparticles (AgNPs) using aqueous extract of Jasminum subtriplinerve leaves as a reducing agent. The nanocomposite AgNPs/HPCD/Alg was characterized by UV-vis, EDX, TEM, HR-TEM analysis. The AgNPs were found to be spherical shape and uniform size with an average diameter of 13.5 nm. EDX data showed about 4.0% (w/w) of AgNPs capped on the nanocomposite HPCD/Alg. The role of HPCD and Alg in the nanocomposites was observed from FTIR and thermal studies. The stability and distribution of the nanoparticles in the aqueous solution were determined by zeta potential and DLS measurements. The nanocomposites showed excellent catalytic performance for degradation of pollutants within industrial effluents including 4-nitrophenol, methyl orange and rhodamine B.

One new cycloartane triterpenoid, named markhacanasin C (1), together with three known triterpenoids, oleanolic acid (2), ursolic acid (3) and 6β,19α-dihydroxyursolic acid (4) were isolated by various chromatographic methods from the most cytotoxic fraction of the ethyl acetate extract of Markhamia stipulata var. canaense V.S. Dang leaves. Among them, 4 was reported for the first time from the genus Markhamia, while 2 and 3 were found for the first time from this species. Their structures were elucidated by IR, UV, HR-ESI-MS and NMR experiments. The cytotoxicity of isolated compounds (3 and 4) against three human cancer cell lines (HeLa, HepG2, and MCF-7) were evaluated. At the concentration of 100 μg/mL, 3 exhibited significant cytotoxic activity (86.36 ± 3.69%).

From the leaves of Schefflera sessiliflora De P. V., one new C20-gibberellin diterpene 2β,12β-dihydroxygibberellin (12β-hydroxy-GA110 or 2β-hydroxy-GA112) (1), together with three known compounds, trans-tiliroside (2), kaempferol 3-O-β-D-glucuronopyranoside (3), 5-p-trans-coumaroylquinic acid (4), was isolated for the first time from the genus Schefflera by various chromatography methods. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments and comparison with previous reported data. The α-glucosidase inhibitory activity of all compounds was measured. The isolates (2, 3) showed better α-glucosidase inhibitory activity (IC50 = 134.60, 147.10 μM, respectively) than the standard drug acarbose (IC50 = 214.50 μM).

One new flavonol glycoside named visconoside C (1), together with seven known flavonol glycosides, quercetin 3-O-β-d-glucopyranoside 7-O-α-l-rhamnopyranoside (2), quercetin 7-O-α-l-rhamnopyranoside (3), astragalin (4), kaempferol 3-O-(4-O-acetyl)-α-l-rhamnopyranoside (5), kaempferol 7-O-α-l-rhamnopyranoside (6), kaempferitrin (7) and kaempferol 3-O-β-d-glucopyranoside 7-O-α-l-rhamnopyranoside (8) were isolated by various chromatography methods from the leaves of Cleome viscosa L. Their structures were elucidated by IR, UV, HR-ESI-MS and NMR (1D & 2D) experiments. The cytotoxicity and hepatoprotective activities using HepG2 human hepatoma cell line of 1 were measured by MTT assay. At the concentration of 25 μM and 50 μM, 1 showed cytotoxic activity against HepG2 cells (cell viability was decreased to 22.2 and 23.0%, respectively, compared with doxorubicin control), while at the concentration of 100 μM, 1 showed hepatoprotective activity against CCl4-induced hepatotoxicity on HepG2 cells (34.3%, compared with quercetin control).

From the fruit of Pandanus tectorius Parkinson ex Du Roi, one new (1) and six known aldehyde compounds (2-7) were isolated by various chromatography methods. Based on their spectroscopic data, these compounds were identified as (Z)-4-hydroxy-3-(4-hydroxy-3-methylbut-2-en-1-yl) benzaldehyde (1), p-hydroxybenzaldehyde (2), syringaldehyde (3), (E)-ferulaldehyde (4), (E)-sinapinaldehyde (5), vanillin (6) and 5-hydroxymethylfurfual (7). The α-glucosidase inhibitory activity of all compounds was measured. The isolated compounds (1-6) showed better α-glucosidase inhibitory activity (IC50 values ranging from 36.5 to 192.4 μM) than the standard drug acarbose (IC50 = 214.5 μM).

From the leaves of Schefflera sessiliflora De P. V., two new triterpene saponins including one oleanane-type saponin, named scheffleraside C (1) and one lupane-type saponin scheffleraside D (2), together with six known triterpene saponins (3–8), were isolated by various chromatography methods. Among them, 3 was found for the first time from natural sources, while 6–8 were isolated for the first time from the genus Schefflera. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR 1D and 2D experiments, and comparison of their NMR data with previously reported data. Their α-glucosidase inhibition and cytotoxic activity against MCF-7 human breast cancer cell lines were evaluated. The isolates (1, 3–5, 8) showed stronger α-glucosidase inhibitory activity (IC50 = 5.99–76.58 μM) than the standard drug acarbose (IC50 = 214.50 μM). At the concentration of 100 μg/ml, the isolates (1, 2) showed appreciable cytotoxic activity (67.92, 63.83%, respectively).

One new flavonol glycoside, named cleomeside C (1), together with eight known flavonol glycosides (2–9) were isolated by various chromatography methods from the leaves of Cleome chelidonii. Their structures were elucidated by IR, UV, HR-ESI-MS, NMR (1D & 2D) experiments. Compounds 2–8 were isolated for the first time from the genus Cleome. The cytotoxicity and hepatoprotective activity in HepG2 human hepatoma cell line of compounds (1–3 and 6) were measured by MTT assay. At the concentration of 25 μM and 50 μM, compound 2 as well as compound 3 at 25 μM showed cytotoxic activity (cell viability was decreased 21.7%, 31.8% and 21.8%, respectively, compared to control). Compounds 2 and 6 expressed hepatoprotective effect at the concentration of 100 μM with prevention percentage of 32.3% and 34.3%, respectively, compared to that of 80.3% of quercetin positive control).