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One new 8,4’-oxyneolignan (1) and one new 7,8-dihydrobenzofuranone (2), together with twenty-one known compounds (3‒23) were isolated from the methanol extract of Rhizophora apiculata leaves. The structures of new compounds, as well as their absolute configuration, were determined by a combination of spectroscopic methods and quantum chemical calculations of NMR and ECD data. All isolated compounds were evaluated for their cytotoxicity, and only 2,6-dimethoxy-1,4-benzoquinone (8) exhibited inhibitory effects against SK-LU-1, HepG2, and MCF7 cells with IC50 values in the range of 8.33–14.82 μM.

Aplydactylonins A-C (1–3), three new sesquiterpenes, were isolated from the Vietnamese sea hare Aplysia dactylomela. Their structures and absolute configurations were elucidated based on spectroscopic analysis, X-ray crystallography, and density functional theory (DFT) calculations of NMR and ECD data. Compound 2 exhibited cytotoxicity against HepG2, DU145 and A549 cells with respective IC50 values of 4.08 ± 0.63, 38.64 ± 1.04 and 12.33 ± 0.95 µM. In addition, HepG2 cells treated with 5 μM compound 2 for 48 h showed a significant increase in early apoptotic cells (P

A new rhamnofolane-type diterpenoid (1) and a new phenolic derivative (2), together with eleven known compounds, were isolated from the leaves of E. cochinchinensis Lour. The chemical structures of these compounds were elucidated based on extensive spectroscopic analysis, including HR-QTOF-MS and NMR, and comparison with reported data. The inhibitory effects of compounds 1–13 on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells were evaluated. As the obtained results, compound 9 showed a moderate inhibitory effects on NO production activity with an IC50 of 6.17 ± 0.25 µM, relative to that of the positive control cardamonin.

The total mean ∑ $$15\overline{\text{PAHs}}$$ in samples were from 75.3 to 387.0 ng/g dry weight (d.w) and showed high value in black dry tea, followed by herbal, oolong, and green tea. The mean ∑ $$\overline{\text{PAH4}}$$ (a combination of benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) values were 54.3 ng/g, 16.4 ng/g, 14.2 ng/g, and 6.6 ng/g for black, herbal, green, and oolong teas, respectively. Concentration for benzo[a]pyrene (BaP) was from 0.4 to 35.8 ng/g, and the BaP equivalent concentration values ranged from 0.3 to 48.1 ng/g. There was only 1 black tea sample that BaP concentration exceeded the maximum level according to European Union (EU) standards. Tea samples marketed in Vietnam showed insignificant difference with the samples from other origins by same analytical method. Black teas showed high PAHs contents in dry tea samples but the released percentage of sum of PAHs from tea-to-tea infusion was lower than that in other tea type samples. The released percentages of PAH4 from tea-to-tea infusion were 40.7, 15.4, and 1.9 for green, herbal, and black tea. High temperature in black tea manufacturing processes might reduce essential oil content in tea that might effect on the PAHs partially release into the infusion. Indeed, based on EU regulations, we may conclude that tea consumers are safe in risk of exposure to PAHs obtained from teas.

Thin films were deposited on SUS440 stainless steel samples by arc plasma evaporation at substrate bias voltages of 10–100 V. X-ray diffraction, optical microscopy, field emission scanning electron microscopy, energy dispersive spectroscopy, microhardness test, and electrochemical test were used to investigate the morphology and properties of the thin films. Particularly, the thin films were composed of chromium nitride (CrN, phases of CrN + Cr) and 0.76 mm thick. They were deposited with microdroplets on the samples. The surface hardness of these films reached the highest value of 1492 HV at the bias of 20 V. As the bias voltage increased, the adhesion of the CrN thin films decreased. The excessively high bias voltage of 100 V led to the delamination of the CrN thin films. The electrochemical test demonstrated that the corrosion resistance in the 3% NaCl solution of CrN coating can be improved.

The rise in Plasmodium falciparum resistance to dihydroartemisinin-piperaquine in Vietnam justifies the need to evaluate alternative artemisinin-based combination therapies. Between July 2018 and October 2019, a single-arm trial of pyronaridine-artesunate (Pyramax, PA) was conducted in Dak Nong province, Vietnam. PA (3-day course) was administered to adults and children infected with P. falciparum. PA was well tolerated by the participants. The proportion of patients with Day 42 PCR-corrected adequate clinical and parasitological response was 95.2% (95% confidence interval [CI], 82.3 to 98.8, n = 40/42) for treating falciparum malaria. The median parasite clearance half-life was 6.7 h (range, 2.6 to 11.9) and the median parasite clearance time was 72 h (range, 12 to 132) with 44.9% (22/49) of patients having positive blood films at 72 h. The two patients that recrudesced had comparable Day 7 blood pyronaridine concentrations (39.5 and 39.0 ng/ml) to the 40 patients who did not recrudesce (median 43.4 ng/ml, 95% CI, 35.1 to 54.9). Ring-stage and piperaquine survival assays revealed that of the 29 P. falciparum isolates collected from the patients before PA treatment, 22 (75.9%) had reduced susceptibility to artemisinins and 17 (58.6%) were resistant to piperaquine. Genotyping confirmed that 92.0% (46/50) of falciparum patients were infected with parasites bearing the Pfkelch13 C580Y mutation associated with artemisinin resistance. Of these, 56.0% (28/50) of the isolates also had multiple copies of the plasmepsin 2/3 genes responsible for piperaquine resistance. Overall, PA was effective in treating P. falciparum in the Central Highlands of Vietnam. (This study has been registered at AustralianClinicalTrials.gov.au under trial ID ACTRN12618001429246.).

Seven anthraquinones including two new compounds namely capillasterquinones A and B (1 and 2) and one new butenolide namely capillasterolide (8) were isolated and structurally elucidated from the crinoid Capillaster multiradiatus. The inhibitory effect of compounds 1-8 on lipopolysaccharide (LPS)-induced nitric oxide (NO) production as well as inhibition of 1 on expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) proteins in RAW264.7 cells were also evaluated. As the obtained results, capillasterquinone A (1) showed strong NO production inhibitory activity with an IC50 of 5.89±0.11 µM. In addition, compound 1 reduced the LPS-induced iNOS and COX-2 expressions in a dose-dependent manner.

Fifteen steroids, including two new compounds, leptosteroid (1) and 5,6β-epoxygorgosterol (2), were isolated and structurally elucidated from the Vietnamese soft coral Sinularia leptoclados. Their cytotoxic effect against a panel of eight human cancer cell lines was evaluated using sulforhodamine B (SRB) method. Significant cytotoxicity against hepatoma cancer (HepG2, IC50=21.13±0.70 µM) and colon adenocarcinoma (SW480, IC50=28.65±1.53 µM) cell lines were observed for 1 and against acute leukemia (HL-60, IC50=20.53±2.26 µM) and SW480 (IC50=26.61±1.59 µM) for ergost-5-en-3β,7β-diol (8). In addition, 3β,7β-dihydroxyergosta-5,24(28)-diene (13) showed significant cytotoxic activity on all tested cell lines with IC50 values ranging from 13.45±1.81 to 29.01±3.21 µM.

Grey mangrove (Avicennia marina) is a traditional medicine used for the treatment of various diseases, including rheumatism and ulcers; however, the compounds responsible for its curative effects remain largely unknown. Triterpenoids are a diverse group of plant-specialized metabolites derived from a common precursor, 2,3-oxidosqualene. Triterpenoids are potentially responsible for the beneficial effects of A. marina; however, the chemical profiles of triterpenoids in A. marina and their biosynthetic genes have not been identified. Cytochrome P450 monooxygenases (P450s) have key roles in the structural diversification of plant triterpenoids by catalyzing site-specific oxidation of triterpene scaffolds. Recent studies have revealed that the CYP716 family represents the most common clade of P450s involved in triterpenoid biosynthesis. In this study, we performed triterpenoid profiling and RNA sequencing of A. marina leaves. Mining of CYP716 family genes and enzymatic activity assays of encoded proteins revealed that CYP716A259 catalyzed oxidation at the C-28 position of the pentacyclic triterpene skeletons of β-amyrin, α-amyrin, and lupeol to produce oleanolic acid, ursolic acid, and betulinic acid, respectively. The other functionally defined P450, CYP716C53, catalyzed the C-2α hydroxylation of oleanolic acid and ursolic acid to produce maslinic acid and corosolic acid, respectively. The possible involvement of CYP716A259 and CYP716C53 in the biosynthesis of these health-benefiting compounds in A. marina leaves, and the possible contribution of the resulting compounds to the reported bioactivities of A. marina leaf extract, are discussed.

Two new pyrrole oligoglycosides, plancipyrrosides A and B (1 and 2), were isolated from methanol extract of the Vietnamese starfish Acanthaster planci using various chromatographic procedures. Their structures were elucidated by spectroscopic methods including one and two dimensional (1D- and 2D)-NMR and Fourier transform ion cyclotron resonance (FT-ICR)-MS. The finding of 1 and 2 represents the third case of pyrrole oligoglycosides obtaining reported to date. Moreover, plancipyrroside B (2) exhibits a potent inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells with IC50 of 5.94±0.34 µM, whereas plancipyrroside A (1) shows this inhibitory activity with IC50 of 16.61±1.85 µM.

Four new polyoxygenated sterol derivatives (1-4) along with the compounds (5-7) previously known from other biological sources were isolated from the gorgonian Menella woodin, collected from the Vietnamese waters. Structures of 1-4 were elucidated by the detailed NMR spectroscopic and mass-spectrometric analyses as well as comparison with those reported in literature data. Compounds 1, 4, and 6 decrease the production of reactive oxygen species (ROS) by the murine macrophages of RAW 264.7 line at induction by endotoxic lipopolysaccharide (LPS) from Escherichia coli.

Nepenthes mirabilis (Lour.) Rafarin (Nepenthaceae) is a carnivorous plant used as a folk medicine in the treatment of jaundice, hepatitis, gastric ulcers, ureteral stones, diarrhea, diabetes, and high blood pressure. Neither the phytochemical content nor biological activities of N. mirabilis have been reported.The anti-inflammatory activity from the N. mirabilis methanolic extract led to the isolation of compounds (1-26).Chromatographic methods were used to isolate compounds from the methanol extract of N. mirabilis branches and leaves. The anti-inflammatory activity of these isolated compounds was investigated in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) using ELISA. Primary BMDCs were used to examine the production of pro-inflammatory cytokines (IL-12 p40, IL-6, and TNF-α, at concentrations of 0.1, 0.2, and 1.0 μM) as compared with a positive control, SB203580 (1.0 μM). MTT assays showed that isolated compounds (1-26) did not exhibit significant cytotoxicity at concentrations up to 20.0 μM.Compound 9 showed potent inhibition of IL-12 p40, IL-6, and TNF-α production (IC50 = 0.17 ± 0.02, 0.46 ± 0.01, and 8.28 ± 0.21 μM, respectively). Compound 4 showed potent inhibition of IL-12 p40 and IL-6 production (IC50 = 1.17 ± 0.01 and 2.15 ± 0.04 μM). In addition, IL-12 p40 inhibition by naphthalene derivatives (1-7, 9, and 10), phenolic compounds (11-15), lupeone (18), and flavonoids (22, 25, and 26) was more potent than with the positive control. The isolated compounds exhibited little and/or no inhibitory effects on TNF-α production in LPS-stimulated BMDCs.Taken together, these data suggest that the isolated components have significant inhibitory effects on pro-inflammatory cytokine production and warrant further study concerning their potential medicinal use.

Using combined chromatographic methods, two asterosaponins (compounds 1 and 2), including a new compound novaeguinoside E (compound 1), and six glycosylated polyhydroxysteroids (compounds 3-8) were isolated from a methanol extract of the starfish Culcita novaeguineae. Their structures were determined on the basis of spectroscopic data ((1)H and (13)C NMR, HSQC, HMBC, (1)H-(1)H COSY, ROESY, and HRESI-MS) and by comparison with the literature values. The new compound 1 represents the third example of asterosaponins containing the 5α-cholesta-9(1l)-en-3β,6α,20,22-tetraol aglycone. Among isolated compounds, 4-7 exhibited moderate to weak cytotoxic activities against five human cancer cell lines such as Hep-G2 (hepatoma), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma).

The methanolic extract of Nepenthes mirabilis (Nepenthaceae) showed significant in vitro antioxidant (peroxyl radical-scavenging and reducing effects) and anti-osteoporotic (pre-osteoclastic RAW 264.7 cells) activities. Phytochemical investigation of chloroform and ethyl acetate partitions of N. mirabilis branches and leaves allowed to isolate 13 compounds (1–13), including two new naphthoquinones, nepenthones F (1) and G (2), together with 11 known compounds. The structures of the isolated compounds were established mainly by extensive analysis of the 1D and 2D NMR, as well as HRMS data. The isolated compounds also were further evaluated for in vitro antioxidant and anti-osteoclast activities. Among them, compounds 10 and 11 showed potent antioxidant effects. While compounds 4 and 12 showed significant inhibition on receptor activation for nuclear factor κB ligand (RANκL)-induced osteoclast formation in murine bone-marrow macrophages.

Two new naphthalene diglucosides named nepenthosides A (1) and B (2), together with eleven known compounds (3–13), were isolated from the carnivorous plant Nepenthes mirabilis. The structures of these compounds were elucidated based on extensive spectroscopic analysis, including 1D- and 2D-NMR, and MS. The antioxidant activities of compounds 1–13 were evaluated in terms of their peroxyl radical-scavenging (trolox equivalent, TE) and reducing capacities. All isolates showed peroxyl radical-scavenging and reducing activities at concentrations of 1.0 and 10.0 μM. Anti-osteoporotic activities were investigated using murine osteoclastic RAW 264.7 cells. Compounds 1–7 and 9–12 significantly suppressed tartrate-resistant acid phosphatase activity down to 91.13 ± 1.18 to 42.39 ± 1.11 %, relative to the control (100 %) in nuclear factor-κB ligand (RANκL)-induced osteoclastic RAW 264.7 macrophage cells.

Five new tirucallane saponins, paramignyosides A-E (1-5), were isolated from the water fraction of the Paramignya scandens stem and leaves. Their structures were elucidated on the basis of spectroscopic evidence including high-resolution electrospray ionization mass spectrometry (HR-ESI-MS) and one dimensional (1D)- and 2D-NMR. The effects of isolated compounds on pro-inflammatory cytokines were evaluated by measuring the production of interleukin (IL)-12 p40, IL-6, and tumor necrosis factor-α (TNF-α) in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs). Paramignyoside C (3) exhibited selective and potent inhibitory effect (IC50=5.03±0.19 µM) on the production of IL-12 p40 comparable to that of the positive control, SB203580 (IC50=5.00±0.16 µM). Further studies are required to confirm efficacy in vivo and the mechanism of anti-inflammatory effects.

Ten biscembranoids (1-10), including the two new compounds sarcophytolides M and N (1 and 2), were isolated from the methanol extract of the Vietnamese soft coral Sarcophyton pauciplicatum. Their structures were elucidated by spectroscopic methods including one dimensional (1D)- and 2D-NMR, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS), and circular dichroism (CD). The in vitro cytotoxic activity of all isolated compounds against a panel of eight human cancer cell lines including HepG2 (hepatoma cancer), HL-60 (acute leukemia), KB (epidermoid carcinoma), LNCaP (prostate cancer), LU-1 (lung cancer), MCF7 (breast cancer), SK-Mel2 (melanoma), and SW480 (colon adenocarcinoma) was evaluated using the sulforhodamine B colorimetric assay. Among the isolated biscembranoids, 1, 3, 4, 7, 9, and 10 exhibited significant cytotoxic effects and may be selected for further studies of their anticancer activity.

Eight compounds were isolated from the leaves of Clerodendrum inerme, including one new rearranged abietane diterpene, crolerodendrum B (1). Their structures were determined by means of spectroscopic methods including one-dimensional and two-dimensional nuclear magnetic resonance (1-D and 2-DNMR), high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) and circular dichroism (CD). The DPPH radical scavenging and cytotoxic activities of isolated compounds against MCF7 (breast), HCT116 (colon) and B16F10 (melanoma) cancer cell lines were evaluated. Compounds 1, 3 and 4 exhibited strong DPPH radical-scavenging effects (ED50 values of 17.6 ± 2.1, 10.1 ± 0.8 and 11.3 ± 0.3 μM, respectively) and 4 showed strong cytotoxicity against the HCT116 cell line (IC50 = 3.46 ± 0.01 μM).

Using various chromatographic separation techniques, ten flavonoid glycosides, including six new compounds namely barringosides A-F (1-6), were isolated from a methanol extract of the Barringtonia acutangula leaves. The structure elucidation was confirmed by spectroscopic analyses, including 1D and 2D NMR, and HR ESI MS. Their inhibitory effects on LPS-induced NO production in RAW264.7 cells were also evaluated. Among the isolated compounds, quercetin 3-O-β-d-(6-p-hydroxybenzoyl)galactopyranoside (9) showed significant effect with an IC50 of 20.00±1.68µM. This is the first report of these flavonoid glycosides from Barringtonia genus and their inhibition on LPS-induced NO production in RAW264.7 cells was reported here for the first time.

Using various chromatographic separations, four sesquiterpenes (1–4), including two new compounds, nanolobatols A and B (1 and 2), were isolated from the Vietnamese soft coral Sinularia nanolobata. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H–1H COSY, NOESY and FT-ICR-MS) and by comparison with the literature values. The cytotoxic activity of isolated compounds against a panel of eight human cancer cell lines was also evaluated.

Background The overproduction of nitric oxide (NO) is known to involve in various inflammatory processes. A methanol extract of the tubers of Ophiopogon japonicus was found to strongly inhibit NO production. The present paper deals with the isolation, structural identification and NO inhibitory effect of five compounds isolated from the MeOH extract of O. japonicus tubers. Results Three new compounds were elucidated to be (2R)-(4-methoxybenzyl)-5,7-dimethyl-6-hydroxyl-2,3-dihydrobenzofuran (1), 2-(2-hydroxyl-4-methoxy-benzyl)-5-methyl-6-methoxyl-2,3-dihydrobenzofuran (2), and 2-(4-hydroxy-benzyl)-5,6-dihydroxybenzofuran (3). In addition, two known compounds were isolated from a natural source for the first time including 2-(4-methoxy-benzyl)-6,7-dimethoxyl-2,3-dihydrobenzofuran (4), and 2-(4-methoxy-benzyl)-6,7-methylenedioxy-2,3-dihydrobenzofuran (5). The absolute configuration of compound 1 was determined by experimental and calculated circular dichroism spectra. The effects of the isolated compounds on LPS-induced NO production in RAW264.7 cells were evaluated. Compound 1 and 2 showed the inhibitory activity with IC50 values of 11.4 and 29.1 μM, respectively. Conclusions The class of 2-benzyl-2,3-dihydrobenzofuran is uncommon in nature. In this work, three such compounds were isolated from O. japonicus. Two of them showed promising anti-inflammatory activity by inhibition of NO production. Electronic supplementary material The online version of this article (doi:10.1186/s13065-017-0242-z) contains supplementary material, which is available to authorized users.

Using various chromatographic separations, three triterpene tetraglycosides (1–3), including one new compound, namely stichorrenoside E (1) along with thelenotoside B (2) and deacetyl thelenotoside B (3), were isolated from the MeOH extract of the Vietnamese sea cucumber Stichopus horrens. Their structures were confirmed by spectroscopic experiments, such as 1D and 2D NMR and HR-ESI-MS. Deacetylated thelenotoside B (3) is firstly isolated as a natural product. Among these compounds, thelenotoside B (2) showed strong cytotoxicities against five human cancer cell lines as HepG2, KB, LNCaP, MCF7 and SK-Mel2 with the IC50 values from 0.95 ± 0.08 to 1.90 ± 0.13 μM, whereas stichorrenoside E (1) and deacetyl thelenotoside B (3) exhibited significant activities with the IC50 values from 6.87 ± 0.25 to 11.62 ± 1.05 μM.

Two new guaiane sesquiterpene lactones, vulgarolides A and B (1 and 2), were isolated from Artemisia vulgaris aerial parts using various chromatographic separations. The structure elucidation was performed by combination of spectroscopic experiments including 1D and 2D NMR, HR ESI MS, and CD. Their in vitro cytotoxic activities against five human cancer cell lines were also evaluated using SRB method.

In a search for anti-inflammatory activity in resources from Vietnamese mangroves, we found that a methanolic extract from the leaves of Calophyllum inophyllum (CIL) showed significant anti-inflammatory effects in vitro. Using various chromatographic techniques, we subsequently isolated 12 compounds (1–12) from a methanolic extract of CIL, including two novel compounds (1–2). The inhibitory effects of these compounds on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells were also evaluated. Compound 1 significantly suppressed NO production (IC50 = 2.44 ± 0.88 µM), the secretion of pro-inflammatory cytokines (including interleukin-1 beta and tumor necrosis factor alpha), and the expression of inducible nitric oxide synthase through downregulation of nuclear factor-kappa-B signaling cascades. These results suggest that C. inophyllum leaves might be a useful resource for the development of drugs for the treatment of inflammation.

Using combined chromatographic separations, two new steroid glycosides namely pentacerosides A (1) and B (2), and four known compounds were isolated from the methanol extract of the starfish Pentaceraster gracilis. Their structures were determined on the basis of spectroscopic data (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, ROESY, and FT-ICR-MS) and by comparing obtained results to the literature values. Among the isolated compounds, only maculatoside (5) showed significant cytotoxic effect against Hep-G2 (IC50 = 16.75 ± 0.69 μM) and SK-Mel2 (IC50 = 19.44 ± 1.45 μM) cell lines and moderate effect on KB (IC50 = 36.53 ± 0.78 μM), LNCaP (IC50 = 39.75 ± 3.34 μM), and MCF7 (IC50 = 47.34 ± 7.01 μM) cell lines.

Using various chromatographic separations, three cholestane-type steroids were isolated from the methanol extract of the octocoral Verrucella corona. Their structures were elucidated to be (22E)-cholesta-5,22-dien-3β-ol-7-one (1), trans-liagosterol (2), and guggulsterol-II (3), by detailed analysis of the 1D and 2D-NMR data as well as comparison with those reported. Among them, compound 2 showed significant cytotoxicity against eight human cancer cell lines as HepG2, HL-60, KB, LNCaP, LU-1, MCF7, SK-Mel2, and SW480.

Chemical investigation of Kandelia candel resulted in the isolation of 19 compounds (1–19), including one new sesquiterpene glycoside, kandelside (1), three megastigman glycoside compounds (7–9), 16 known phenolic compounds (2–6 and 10–19). Structures of the isolated compounds were elucidated based on spectral data comparison with reported values. Isolated compounds were also evaluated for their inhibitory effects on the production of pro-inflammatory cytokines interleukin (IL)-12 p40, IL-6, and tumor necrosis factor α (TNF-α) in lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells. Among these compounds, compound 9 exhibited strong inhibitory activity against IL-6 production (IC50 = 0.07 ± 0.05 μM) and moderate inhibitory activity against TNF-α production (IC50 = 49.86 ± 1.02 μM), but exhibited no activity on IL-12 p40 production. Compounds 5 and 6 significantly inhibited IL-12 p40, IL-6, and TNF-α production with IC50 values of 11.68 ± 0.38, 44.52 ± 1.08, and 28.73 ± 0.96 μM, respectively.

Chromatographic purification of the methanolic extract from the soft coral Sarcophyton pauciplicatum led to the isolation of three polyhydroxylated steroids 1 – 3 , including a new compound, sarcopanol A ( 1 ). Their structures were elucidated by spectroscopic analysis and by comparison of the spectroscopic data with those of similar compounds previously reported in literature. The anti-inflammatory effects of isolated compounds were evaluated using nuclear factor kappa B (NF-κB) luciferase and reverse transcription polymerase chain reaction (RT-PCR). The effect of isolated compounds on cell growth was evaluated by MTS assays. Compounds 1 and 2 significantly inhibited TNFα/INFγ-induced NF-κB transcriptional activity in human keratinocyte (HaCaT) cells in a dose-dependent manner, with EC 50 values of 8.27 ± 3.28 and 26.07 ± 5.59 μM, respectively. Furthermore, the transcriptional inhibition of these compounds was confirmed by a decrease in cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and intercellular adhesion molecule-1 (ICAM-1) gene expression levels in HaCaT cells.

This study performed phytochemical and bioactive assessments of the mangrove Lumnitzera racemosa Willd. leaves. Bioassay-guided fractionation of the methanolic extracts led to the identification of thirty-six compounds (1–36), their structures were elucidated using detailed NMR spectroscopic and MS analysis. The extracts, fractions, and the isolated compounds were screened for potential antioxidant and cytotoxic activities. Antioxidant assays were performed using peroxyl radical-scavenging and reducing assays, whereas cytotoxicity was measured using MTT assays in HL-60 and Hel-299 cell lines. The methanolic extract, CH2Cl2 and n-BuOH fractions (10.0 μg/mL) exhibited potent antioxidant activity, with Trolox equivalent (TE) values of 24.94 ± 0.59, 28.34 ± 0.20, and 27.09 ± 0.37 (μM), respectively. In addition, the isolated compounds exerted cytotoxic effects in a dose-dependent manner; compounds 1 and 14 exhibited the most potent cytotoxicity in HL-60 cells, with IC50 values of 0.15 ± 0.29 and 0.60 ± 0.16 μM, respectively. To clarify the mechanism(s) behind these cytotoxic effects, we measured the time-dependent changes in apoptotic markers including the condensation and fragmentation of nuclear chromatin, and the downregulation of p-ERK1/2, p-AKT, and c-Myc levels.

One new flavone derivative, urinariaflavone (1), and eight known compounds (2–9) were isolated from the methanolic extract of Phyllanthus urinaria L. leaves. Their structures were established by MS, 1D and 2D NMR experiments, and comparison with literature data. All isolated compounds were tested for their cytotoxic activity against CHO (Chinese hamster ovary) and J774 (Murine macrophage) cell lines. Cytotoxic effects (IC50s ∼ 6.00–41.30 μM) on both cell lines were observed for compounds 4, 5, and 7.

Bioassay guided fractionation led to the isolation of a new triterpene glycoside, holothurinogenin B (1) along with three known compounds, holothurin B (2), holothurin A (3), and holothurin A2 (4), from the methanol extract of the Vietnamese sea cucumber Holothuria scabra. Their structures were deduced from the spectral analysis (1D-NMR, 2D-NMR, MS) and chemical evidences.

Nine secondary metabolites, including a new cycloartane glucoside, rhizostyloside (1), were isolated from a methanol extract of Rhizophora stylosa leaves through several chromatographic experiments. The structures of the compounds were determined on the basis of NMR spectroscopic (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, NOESY) and HR-ESI-MS data and by comparison with literature values. Compound 1 exhibited significant cytotoxicity against three human cancer cell lines: KB (epidermoid carcinoma), LU-1 (lung adenocarcinoma), and SK-Mel-2 (melanoma). In addition, 1 strongly activated caspase-3/7 in LU-1 cells.

The pure rotational spectrum of OCS has been studied by Fourier transform at room temperature over the frequency range 20–42cm −1 . The ground state rotational lines were observed for OC 32 S up to J = 103. It has been possible also to identify the rotational lines for OC 34 S in the ground state and for OC 32 S in the ν 1 = 1 level.

The so-called A′·type amino wagging band of CH3NH2 has been reexamined by using 0.25 cm−1 resolution i.r. spectroscopy. It is found that the central portion of the band, reported hitherto as a plateau, is resolved into multiplets. The observed fine structure of the Q-branch absorption lines are shown to be in agreement with calculations based on theory for the coupling between the inversion and internal rotation of methylamine.