In vitro and in silico docking and molecular dynamic of antimicrobial activities, alpha-glucosidase, and anti-inflammatory activity of compounds from the aerial parts of Mussaenda saigonensis.

Twelve compounds were isolated from Mussaenda saigonensis aerial parts through phytochemical analysis and the genus Mussaenda is the first place where the compounds 4-6 and 11-12 have been found. Based on the ability to inhibit NO production in RAW264.7 cells, compound 2 has demonstrated the strongest anti-inflammatory activity in vitro with an IC50 of 7.6 µM, as opposed to L-NMMA's IC50 of 41.3 µM. Compound 12 was found to be the most effective inhibitor of alpha-glucosidase enzyme in vitro, with an IC50 value of 42.4 µM (compared to 168 µM for acarbose). Compounds 1-12 were evaluated in vitro for antimicrobial activity using the paper dish method. Compound 11 demonstrated strong antifungal activity against M. gypseum with a MIC value of 50 µM. In silico docking for antimicrobial activity, pose 90 or compound 11 docked well to the 2VF5 enzyme, PDB, which explains why compound 11 had the highest activity in vitro. Entry 2/pose 280 demonstrated excellent anti-inflammatory activity in silico. The stability of the complex between pose 280 and the 4WCU enzyme for anti-inflammatory activity has been assessed using molecular dynamics over a simulation course ranging from 0 to 100 ns. It has been found to be stable from 60 and 100 ns. The Tyr 159 (95%, H-bond via water bridge), Asp 318 (200%, multiple contacts), Met 273 (75%, hydrophobic interaction via water bridge), and Gln 369 (75%, H-bond via water bridge) interacted well within the time range of 0 to 100 ns. It has more hydrophilic or polar pharmacokinetics.

Correction: Antimicrobial and alpha-glucosidase inhibitory flavonoid glycosides from the plant Mussaenda recurvata: in vitro and in silico approaches.

[This corrects the article DOI: 10.1039/D4RA00666F.].

Antimicrobial and alpha-glucosidase inhibitory flavonoid glycosides from the plant Mussaenda recurvata: in vitro and in silico approaches.

Seven flavonoid glycosides were isolated from the aerial portions of Mussaenda recurvata during a phytochemical analysis. This comprised one novel component, ecurvoside, and six well-studied compounds, namely astragalin, isoquercitrin, nicotiflorin, rutin, hesperidin, and neohesperidin. The chemical structures of compounds were identified using spectroscopic techniques and a comparison with previously published studies. Alpha-glucosidase inhibition testing was carried out on all isolated compounds. The compounds evaluated have IC50 values between 35.6 and 239.1 g mL-1, indicating a moderate degree of inhibition. In vitro antimicrobial activities of compounds 1-7 have screened against the bacteria Pseudomonas aeruginosa (P. aeruginosa), methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus faecalis (Strep. faecalis), and fungi: Candida albicans (C. albicans), Trichophyton mentagrophytes (T. mentagrophytes), and Microsporum gypseum (M. gypseum), where compound 6 showed excellent activity against fungi T. mentagrophytes with an MIC value of 12.5 µM. In accordance with the molecular docking study, ecurvoside (1) or pose 472 interacted well with the 3TOP enzyme: PDB and the molecular dynamic simulations proved that the complex of ecurvoside and 3TOP has a stable simulation time of 50-100 ns and the significant residual amino acids in 3TOP are relative to interactions more than one time such as Asp 960, Glu 961, Lys 1088, Glu 1095, Arg 1097, Gly 1102, Thr 1103, Gln 1109, Glu 1178: A chain and Glu 1095, Thr 1101, and Asp 1107: B chain. The docking studies of compounds 1-7 to the enzyme 2VF5 explain the general mechanism to inhibit bacteria and proved that compound 6 (pose 370) inhibited stronger than compound 7 (pose 362) and compound 5 (pose 280), and compounds 1 to 4 do not interact well with 2VF5.

Silver nanoparticles loaded on lactose/alginate: in situ synthesis, catalytic degradation, and pH-dependent antibacterial activity.

We present the in situ synthesis of silver nanoparticles (AgNPs) through ionotropic gelation utilizing the biodegradable saccharides lactose (Lac) and alginate (Alg). The lactose reduced silver ions to form AgNPs. The crystallite structure of the nanocomposite AgNPs@Lac/Alg, with a mean size of 4-6 nm, was confirmed by analytical techniques. The nanocomposite exhibited high catalytic performance in degrading the pollutants methyl orange and rhodamine B. The antibacterial activity of the nanocomposite is pH-dependent, related to the alterations in surface properties of the nanocomposite at different pH values. At pH 6, the nanocomposite demonstrated the highest antibacterial activity. These findings suggest that this nanocomposite has the potential to be tailored for specific applications in environmental and medicinal treatments, making it a highly promising material.

Essential oils of the ginger plants Meistera caudata and Conamomum vietnamense: chemical compositions, antimicrobial, and mosquito larvicidal activities.

The current study describes the chemical identification, antimicrobial, and mosquito larvicidal activities of essential oils from Meistera caudata and Conamomum vietnamense, growing in Vietnam. Essential oils were extracted from the leaves and rhizomes, and characterized by the GC-FID/MS (gas chromatography-flame ionization detection/mass spectrometry) analysis. Monoterpenes (33.1-89.2 %) were the main chemical class found in these oils. ß-Pinene (30.8 %) and α-pinene (23.8 %) were two major compounds in M. caudata leaf oil. C. vietnamense leaf and rhizome essential oils were dominated by 1,8-cineole (47.9-62.0 %) and limonene (10.3-16.2 %). With the same MIC (minimum inhibitory concentration) value of 25 µg/mL, C. vietnamense leaf and rhizome essential oils strongly inhibited the growth of Gram-positive bacteria Staphylococcus aureus ATCC 29213 and Bacillus subtilis ATCC 6501, respectively. For 24 and 48-h treatments, C. vietnamense leaf essential oil strongly controlled the growth of mosquito Aedes aegypti with the respective LC50 values of 7.67 and 6.73 µg/mL, and the respective LC90 values of 13.37 and 10.83 µg/mL. In the same manner, C. vietnamense rhizome essential oil also showed strong mosquito larvicidal activity against Aedes albopictus with the LC50 values of 12.37 and 12.00 µg/mL, and the LC90 values of 20.56 and 18.58 µg/mL, respectively. C. vietnamense essential essential oils containing a high amount of 1,8-cineole are generally better than M. caudata essential essential oils in both two biological assays.

In vitro anti-inflammatory, in silico molecular docking and molecular dynamics simulation of oleanane-type triterpenes from aerial parts of Mussaenda recurvata.

Bioactive-guided investigation of the aerial parts of Mussaenda recurvata Naiki, Tagane, and Yahara (Rubiaceae) led to the isolation of four triterpenes, including two new triterpenes recurvatanes A and B (1 and 2), along with two known compounds 3ß,6ß,23-trihydroxyolean-12-en-28-oic acid (3) and 3ß,6ß,19α,23-tetrahydroxyolean-12-en-28-oic acid (4). The chemical structures of the compounds were identified from spectroscopic data and by comparison with the literature. A comprehensive review of NMR data of the oleanane-type triterpenes bearing 3-hydroxy and 4-hydroxymethylene groups indicated the characteristic spectroscopic features in this series. Compounds 1-4 were evaluated for the inhibitory NO production in LPS-stimulated RAW264.7 cells. Compounds 2 and 3 showed a moderate reduction of nitrite accumulation with IC50 values of 55.63 ± 2.52 and 60.08 ± 3.17 µM, respectively. Molecular docking model dedicated to compound 3 or pose 420, which is the best candidate among docking poses of compounds 1-4 interacted well with the crystal structure of enzyme 4WCU: PDB. The best ligand molecule, pose 420 in terms of binding energy obtained from docking studies on molecular dynamics (MD) simulations for 100 ns exhibited non-bonding interactions with the protein and remained stable inside the active site.

Recurvataside, a new saponin from aerial parts of Mussaenda recurvata.

A new glycoside, recurvataside (1) and six known compounds, quinovic acid (2), quinovic acid 28-O-ß-D-glucopyranosyl ester (3), 3-O-ß-D-glucopyranosylquinovic acid (4), 3-O-ß-D-glucopyranosylquinovic acid 28-O-ß-D-glucopyranosyl ester (5), pomolic acid (6), and ursolic acid (7) were isolated from aerial parts of Mussaenda recurvata. The structure of compound 1 was identified from its spectroscopic data and by comparison with the literature. Recurvataside represents the first occurrence of δ-oleanolic acid saponin bearing two D-glucose units at C-3 and C-28 in nature. This is the first time δ-oleanane-type saponin reported in the genus Mussaenda. Compounds 1-7 were evaluated the cytotoxicity against two cancer cell lines MCF-7 and HepG2. Among them, only compound 7 exhibited moderate activity against MCF-7 and HepG2 cell lines with IC50 value of 16.97 ± 1.55 and 20.28 ± 1.00 µM, respectively. Compounds 1-7 were also tested for their inhibitory NO production in LPS-stimulated RAW264.7 cells. Compounds 3, 5, and 7 showed significant reduction of nitrite accumulation in LPS-stimulated RAW 264.7 cells with the IC50 values of 8.81 ± 0.48, 13.42 ± 0.84, and 18.37 ± 0.67 µM, respectively.

A new 26-norlanostane from Phlogacanthus turgidus growing in Vietnam.

Chemical investigation on chloroform extract of Phlogacanthus turgidus led to the isolation of one new compound namely turgidol, together with five known triterpenoids, lupeol, lupenone, betulin, betulinic acid, and taraxerol. Their structures and stereochemistry have been determined by 1 D and 2 D NMR analysis, high resolution mass spectrometry, and compared with those in literatures. The relative configuration of turgidol was defined using DFT-NMR chemical shift calculations and subsequent DP4+ probability method. Turgidol, betulin, and betulinic acid were evaluated for cytotoxic activity toward K562 cancer cell line and the alpha-glucosidase inhibition.

New cerebroside and chondrocyte proliferation activity of Caryota mitis L.

Caryota mitis L., a flowering plant, belongs to the family Arecaceae. In Vietnam, its fruits were used to treat joint pain. The present study was designed to investigate the phytochemicals and chondrocyte proliferation activity of C. mitis L. fruits on young human chondrocyte. The results showed that all of extracts (crude extract as well as n-hexane, chloroform, ethyl acetate and methanol fractions) were stimulated the growth of chondrocyte at 0.1 µg/mL; 0.01 µg/mL concentrations, of which the n-hexane and methanol fractions significantly increased the proliferation of chondrocyte by 30.75 and 24.42% at concentrations of 0.01 µg/mL, respectively. Repeated chromatography of the methanol fraction on silica gel, Sephadex LH-20 and ODS columns afforded a new cerebroside and eight known ones. Their structures were elucidated by analysis of spectral data and in comparison with the published reports.

A new benzofuran derivative from the leaves of Ficus pumila L.

A new benzofuran derivative, pumiloside (1), together with seven known flavonoid glycosides, afzelin (2), astragalin (3), quercitrin (4), isoquercitrin (5), kaempferol 3-O-rutinoside (6), rutin (7) and kaempferol 3-O-sophoroside (8) were isolated from the leaves of Ficus pumila. Their structures were established by spectroscopic data and comparison with the literature values.

New naphthalene derivative from the leaves of Cassia grandis L.

Cassia grandis is used for the treatment of skin disorders, back pain, aches, etc. in Vietnamese traditional medicine. In this paper, phytochemicals of the leaves were investigated. A new naphthalene derivative (1, cassgranon D) and, seven known compounds rutin (2), afzelin (3), quercitrin (4), epicatechin (5), (-)-epiafzelechin (6), isoquercitrin (7) and aloe emodin (8) were isolated from the ethyl acetate and methanol extracts. Their structures were elucidated by spectral evidences (UV, IR, MS, 1H, 13C, DEPT, HSQC and HMBC NMR), as well as by comparing with published data.

A new dihydrofurocoumarin from the fruits of Pandanus tectorius Parkinson ex Du Roi.

From the fruit of Pandanus tectorius Parkinson ex Du Roi, one new dihydrofurocoumarin, named pandanusin A (1) and 15 known compounds, including one furanocoumarin (2), two coumarins (3, 4), four lignans (5-8), one neolignan (9), two flavonoids (10, 11), three phenolics (12-14), one monoglyceride (15) and one monosaccharide (16) were isolated by various chromatography methods. Among them, compounds (3-5) were obtained from the Pandanus genus for the first time and compounds (9-14, 16) were reported from this species for the first time. Their structures were elucidated by 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 isolated compounds (1-12, 14) showed better α-glucosidase inhibitory activity (IC50 = 42.2, 36.5, 84.7, 73.2, 40.8, 26.7, 76.5, 33.8, 68.1, 14.4, 22.1, 81.5, 43.8 µM, respectively) than the standard drug acarbose (IC50 = 214.5 µM).

A new flavan from the Drynaria bonii H. Christ rhizomes.

In Vietnam, the medicinal plant Drynaria bonii H. Christ is used for the treatment of osteoporosis, bone fractures, and stimulate the growth of hair, treat tinnitus (Ho 2002; Loi 2004). In this article, experiments were designed to investigate the proliferation activity of ethanol, n-hexane, chloroform, ethyl acetate and methanol extracts from D. bonii rhizomes on MG-63 human osteoblast-like cells. The results showed that methanol and hexane extracts had the ability to proliferate MG-63 cells at the concentration varying from 0.1 to 0.01 µg/mL. In particular, at the concentration of 0.01 µg/mL, hexane and methanol extracts illustrated the highest proliferation ratio with 9.31% and 6.16%, respectively. By column chromatography, a new compound named drynaether A (1) and five known compounds uracil (2), 4'-hydroxy-7-methoxyflavan (3), kaempferol (4), indole-3-carboxylic acid (5) and protocatechuic acid (6) were isolated and identified from the methanol extract.

Two new flavonol glycosides from the leaves of Cleome chelidonii L.f.

From the leaves of Cleome chelidonii L.f., two new flavonol glycosides, named cleomesides A (1) and B (2), and four known compounds, quercetin 3-O-ß-glucopyranosyl(1 â†’ 2)-α-rhamnoside-7-O-α-rhamnoside (3), ethyl α-galactopyranoside (4), adenine (5) and glycerol monostearate (6), were isolated. The structures of all isolated compounds (1-6) were determined by NMR spectroscopy and mass spectrometry. The data of known compounds (3-6) were further compared with the reported data for these compounds.