Four new diterpenoids from the aerial parts of Leucas zeylanica (L.) R. Br.

Four new undescribed halimane- and labdane-type diterpenoids, named zeylleucapenoids E-H (1-4), along with four known analogues (5-8), were isolated from the aerial parts of Leucas zeylanica (L.) R. Br. Their structures were determined by comprehensive spectroscopic analysis and computational calculations. Compounds 1 and 2 are the highly modified halimane diterpenoids featuring a 6/6/6-fused tricyclic system with an unusual six-membered 6,11-ether ring. Compound 8 exhibits nontoxic effects for zebrafish embryo, while it displays efficient reduction against NO production in a dose-dependent manner and strongly suppresses the secretion of LPS-induced TNF-α and IL-6 cytokines in RAW264.7 macrophages. In addition, marked reductions of iNOS and COX-2 expression were observed. Molecular docking analysis indicated that 8 has high affinities with the target amino acid residues on protein-binding sites, which may be a possible mechanism contributing to the anti-inflammatory potential of this molecule.

Alkaloid-metabolites from the mangrove-derived fungus Penicillium robsamsonii HNNU0006.

Nine metabolites, including three undescribed alkaloids pyripyropenes VW (1-2), penicioxa A (4), two previously reported pyripyropene A (3), oxaline (5), three grisephenone-type xanthone derivatives (6-8), and a diphenyl ether derivative 4-chloro-7,4'-dihydroxy-5,2'-dimethoxy-2-methylformate-6'-methybenzophone (9), were isolated from cultures of the mangrove-derived fungus Penicillium robsamsonii HNNU0006. Their structures were determined by spectroscopic analysis, ECD calculations, together with DP4+ probability analysis. Furthermore, all the isolated compounds were tested for cytotoxicity and anti-phytopathogenic fungal activities. Compounds 6-8 showed moderate cytotoxicity against tumor cell lines A549, with IC50 values ranging from 5.68 ± 0.21 to 9.71 ± 0.34 µg/mL, respectively.

Hainanxylogranolides A-F: New Limonoids isolated from the seeds of Hainan mangrove plant Xylocarpus granatum.

Six new limonoids, named hainanxylogranolides A-F (1-6), together with nineteen known ones (7-25) were isolated from the seeds of a Hainan mangrove Xylocarpus granatum. The structures of the new compounds were established by extensive NMR spectroscopic data combined with the DFT and TDDFT calculated electronic circular dichroism spectra. Hainanxylogranolide A (1) is the aromatic B-ring limonoid containing a central pyridine ring and a C-17 substituted γ(21)-hydroxybutenolide moiety. Hainanxylogranolide B (2) belongs to the small group of mexicanolides containing a C3-O-C8 bridge, whereas hainanxylogranolides C and D (3 and 4) are mexicanolides comprising a C1-O-C8 bridge. Compounds 9 and 25 posed obvious inhibition effect on the tube formation of HUVECs. There are only about 25% tube-like structures were observed at the concentration of 40.0 µM of compound 25. The antiviral activities of the isolates against herpes simplex virus-1 (HSV-1) and severe fever with thrombocytopenia syndrome virus (SFTSV) were tested in vitro. Compound 23 exhibited moderate anti-SFTSV activity with the IC50 value of 29.58 ± 0.73 µM. This is the first report of anti-angiogenic effect and anti-SFTSV activity of limonoids from the genus Xylocarpus.

Anthraquinones with potential antiproliferative activities from the fruits of Morinda citrifolia.

The phytochemical investigation on the fruits of Morinda citrifolia led to the isolation and characterization of a new anthraquinone, moricitrifone (1), along with seven known anthraquinones (2-8). The chemical structure of 1 was elucidated by extensive spectral analyses. The known compounds (2-8) were identified by comparing their spectral data with those reported in the literature. The antiproliferative activities of all isolated anthraquinones (1-8) against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 were evaluated in vitro. Compounds 1-8 exhibited remarkable antiproliferative activities with IC50 values ranging from 0.26 ± 0.05 to 16.58 ± 0.18 µM, which were comparable to those of doxorubicin.

Comparison of Phytochemical Constituents and Pharmacological Activities of Various Solvent Extracts Obtained from Millettia speciosa Stem Powder.

Millettia speciosa is a plant extensively used as an important component in Chinese herbal medicine and food-based medicines. The present study was carried out to determine the total flavonoid content (TFC), volatile phytoconstituents, and pharmacological activities, i.e., antityrosinase, sunscreen, and anticancer activity, of different fractions of M. speciosa stem. Different organic solvents of increasing polarity, i.e., petroleum ether (PE), ethyl acetate (EtOAc), and methanol (MeOH), were used for extraction. The highest total flavonoid content, i.e., 48.30 ± 0.90%, was reported for PE extract. Various important phytocomponents were revealed by gas chromatography-mass spectroscopy (GC-MS) analysis. Based on abundance, the major compounds were n-hexadecanoic acid (16.654%), n-hexadecanoic acid (14.808%), and beta-sitosterol (6.298%) for PE, EtOAc, and MeOH extract, respectively. The significant antityrosinase activity, i.e., 70.97 ± 0.66%, with an IC50 value of 4.58 mg/mL was noted for PE extract followed by EtOAc extract, i.e., 59.84 ± 0.67%, with IC50 value of 6.10 mg/mL. The maximum sunscreen activity was reported for PE extract exhibiting the maximum absorbance value (0.633 ± 0.06) in the ultraviolet (UV) region, i.e., UVC, while EtOAc extract showed the second highest level of absorbance in the UVB range, i.e., 0.632 ± 0.07. The strongest anticancer activity (49.73 ± 0.49% cell viability) towards MCF-7 breast cancer cell line was reported for PE extract with IC50 197.51 µg/mL. Our results confirmed the presence of potential therapeutic components for each extract with significant biological functions, showing the importance of the M. speciosa stem as a source of biomedicine. To our knowledge, this is the first report on M. speciosa stem extending comprehensive research about its phytochemical profile and various significant pharmacological activities.

Fermented noni (Morinda citrifolia L.) fruit juice improved oxidative stress and insulin resistance under the synergistic effect of Nrf2/ARE pathway and gut flora in db/db mice and HepG2 cells.

Oxidative stress interferes with blood glucose homeostasis, leading to insulin resistance (IR) and hyperglycemia, which eventually induce type 2 diabetes (T2DM). Fermented noni (Morinda citrifolia L.) fruit juice (FNJ) is a traditional folk medicine in Polynesia as well as a functional food supplement with a variety of health benefits. In this study, the efficacy and mechanism of FNJ in improving oxidative stress and IR were investigated under the synergistic effect of Nrf2/ARE pathway and gut flora in vivo and in vitro. In vitro, insulin resistant HepG2 cells were established with 50 mM high glucose, and 25 µM rosiglitazone (ROSI) was used as a positive control. In vivo, male C57BLKS mice in the CON group were fed a normal diet and C57BLKS/J-db/db (db/db) mice were treated with 10 mg kg-1 d-1 ROSI and 6.5 and 13 mL kg-1 d-1 FNJ for 8 weeks, respectively. The results showed that 3-5% FNJ markedly improved IR by increasing glucose uptake and consumption and ameliorated oxidative stress via up-regulating the expression of related antioxidant enzymes such as SOD and GPx and attenuating ROS and MDA in IR-HepG2 cells. In vivo, db/db mice exhibited hyperglycemia, hyperinsulinemia, and oxidative stress, whereas FNJ significantly inverted those conditions. Moreover, FNJ supplementation notably increased the gut microbiota diversity of T2DM mice and remodeled the gut microbial composition to suppress microbial disorder. Specifically, FNJ increased the ratio of F/B and lowered the Proteobacteria abundance at the phylum level. The db/db mice were enriched in Enterobacteriaceae, Klebsiella, and Klebsiella-pneumonia, while FNJ feeding significantly up-regulated Rikenellaceae. In addition, western blotting and qPCR experiments showed that FNJ promoted the expression of Nrf2, HO-1, IRS1, PI3K, AKT, and GLUT4 and reduced the JNK level both in vivo and vitro. These results confirmed that FNJ had a protective effect on oxidative stress and IR by activating Nrf2/ARE signaling pathway and regulating gut flora in db/db mice and IR-HepG2 cells.

Isolated compounds from Dracaena angustifolia Roxb and acarbose synergistically/additively inhibit α-glucosidase and α-amylase: an in vitro study.

BACKGROUND: As a traditional herbal medicine, Dracaena angustifolia Roxb has been used as an anti-inflammatory agent by the Li people in Hainan, China. In preliminary phytochemical studies conducted in our lab, its fractions were found to inhibit α-glucosidase in vitro, indicating a potential for alleviating glucose dysregulation. METHODS: Through in vitro enzymatic assays, the abilities of the separated components to affect α-glucosidase and α-amylase were evaluated. By establishing concentration gradients and generating Lineweaver-Burk plots, the corresponding inhibition modes together with kinetic parameters were assessed. Following the evaluation of the outcomes of their combination with acarbose, computational docking and molecular dynamic simulations were carried out to analyse the interaction mechanisms and perform virtual screening against human enzymes. RESULTS: Compared with acarbose, 7 compounds, including flavonoid derivatives, amides and aromatic derivatives, with higher α-glucosidase inhibitory efficiencies were confirmed. It was found that those competitive/mixed candidates and acarbose interacted synergistically or additively on α-glucosidase. Moreover, 3 of them were able to inhibit α-amylase in mixed mode, and additive effects were observed in combination with acarbose. Through in silico docking, it was found that the active site residues as well as adjacent residues were involved in α-glucosidase and α-amylase binding, which were mainly achieved through hydrogen bonding. Among those dual-function flavonoids, Compound 9 was predicted to be a considerable inhibitor of human enzymes, as the formation of ligand-enzyme complexes was mediated by the residues responsible for substrate recognition and catalysis, the stabilities of which were reiterated by molecular dynamics simulations. CONCLUSION: Despite their mild effects on α-amylase, considerable α-glucosidase inhibitory efficiencies and potential synergy with acarbose were exhibited by these natural candidates. Furthermore, a stable ligand, human α-glucosidase, was predicted by the performed simulations, which provided useful information for the application of Dracaena angustifolia Roxb in diabetes treatment.

[Chemical constituents with α-glucosidase inhibitory activities from seeds of Morinda citrifolia (Noni)].

The present study investigated the chemical constituents and inhibitory activities against α-glucosidase from the seeds of Morinda citrifolia(Noni) by the chromatographic technique and semi-preparative HPLC.Fifteen compounds were isolated from the ethyl acetate extract of the seeds, and their structures were identified on the basis of physiochemical characteristics and spectroscopic data as(9S,2E,4Z,7Z)-9-hydroxydeca-2,4,7-trienoic acid(1), azelaic acid(2), scopoletin(3), ursolic acid(4), quercetin(5), cyclo-(L-Leu-L-Ile)(6), cyclo-(L-Phe-L-Ile)(7), cyclo-(L-Phe-L-Val)(8), cyclo-(L-Leu-L-Val)(9), cyclo-(L-Phe-L-Leu)(10), caffeic acid(11), 3,4-dihydroxycinnamaldehyde(12), p-hydroxybenzoic acid(13), p-hydroxy-cinnamic acid(14), and p-hydroxyphenethyl alcohol(15).Among them, compound 1 was a new fatty acid and compounds 7-10 and 12 were isolated from Morinda plant in the Rubiaceae family for the first time.Compounds 1, 2 and 4-15 were isolated from the seeds of M.citrifolia(Noni) for the first time.All isolated compounds were evaluated for the inhibitory activities against α-glucosidase and compounds 3-5 showed potential inhibitory activity with IC_(50) values of 160, 133, and 120 µmol·L~(-1), respectively.

A new isoflavone from the fruits of Ficus auriculata and its antibacterial activity.

A new isoflavone (Z)-5,7,4'-trihydroxy-3'-[3-hydroxy-3-methyl-1-butenyl] isoflavone (1) together with seven known isoflavones (2-8) were isolated from the fruits of the Ficus auriculata. Their structures were established on the basis of 1 D, 2 D-NMR spectroscopic data and HR-ESI-MS analysis. All compounds were evaluated for their antibacterial activities against five pathogenic bacteria in vitro. Compounds 3 and 4 exhibited significant antibacterial activities against five pathogenic bacteria with the MIC values ranging from 1.25 to 20 µg/mL.[Formula: see text].

Ethyl acetate extract of the Musa nana flower inhibits osteoclastogenesis and suppresses NF-κB and MAPK pathways.

Banana flowers are consumed as a vegetable and traditionally used for managing several health problems including joint pain, a symptom of bone loss. Osteoclasts are key effector cells responsible for bone loss. Some flavonoids in banana flowers, such as quercetin and quercitrin, have been shown to be able to inhibit osteoclastogenesis. Whether banana flowers can inhibit osteoclast formation is unknown. In this study, we prepared the ethyl acetate fraction (FFE-EA) of an ethanolic extract of fresh flowers of Musa nana. Using UPLC-MS/MS analyses, 76 polyphenols were identified in FFE-EA. In RANKL-stimulated RAW264.7 macrophages, FFE-EA inhibited osteoclastogenesis and osteoclastic bone resorption. Mechanistic studies revealed that FFE-EA suppressed NF-κB and MAPK pathways, and lowered mRNA levels of osteoclast formation/function-related genes. These findings suggest that flowers of M. nana could be a source for formulating functional food that benefits bone health.

Two novel aporphine-derived alkaloids from the stems of Fissistigma glaucescens.

Two novel aporphine-derived alkaloids, aporaloids A and B (1 and 2), together with eight known biogenetically related alkaloids (3-10), two known isoquinoline alkaloids (3 and 4), and six known aporphinoid alkaloids (5-10) were isolated from the stems of Fissistigma glaucescens. Their structures were elucidated using comprehensive spectroscopic methods. Compounds 1 and 2 represent the rare example of a six-membered lactone ring aporphine-derived alkaloids from natural products. The inhibitory activities of all compounds against four cancer cell lines were evaluated. Aporaloids A and B (1 and 2) showed broad spectrum cytotoxic activities.

[Study on secondary metabolites of endophytic fungus Cladosporium sp. JJM22 hosted in Ceriops tagal].

Nine secondary metabolites(S)-5-hydroxy-4-methylchroman-2-one(1), 4-methoxynaphthalene-1,5-diol(2), 8-methoxynaphthalene-1,7-diol(3), 1,8-dimethoxynaphthalene(4),(2R,4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol(5),(2R,4R)-3,4-dihydro-4-methoxy-2-methyl-2H-1-benzopyran-5-ol(6), 7-O-α-D-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one(7),(R)-3-methoxyl-1-(2,6-dihydroxyphenyl)-butan-1-one(8) and helicascolide A(9) were isolated from endophytic fungus Cladosporium sp. JJM22 by using column chromatographies of silica gel and ODS, and semi-preparative HPLC. Their structures were analyzed on the basis of spectroscopic and chemical data, especially NMR and MS. All isolated compounds were evaluated for their anti-inflammatory activities by examining the inhibitory activities on nitric oxide(NO) production induced by lipopolysaccharide in mouse macrophage RAW264.7 cells in vitro. Compounds 2-4 showed inhibitory activities.

New alkaloids from the noni juice with potential α-glucosidase inhibitory activity.

Four new alkaloids, nonialkaloids A-D (1-4) and six known analogues (5-10) were isolated from the noni juice. Among the new compounds, 1 and 2 are indole alkaloids with a seven-membered fused N-heterocyclic ring, 3 and 4 are quaternary ammonium derivatives. The structures were elucidated by extensive NMR and MS analysis, while the absolute configurations of the stereogenic carbons were established based on quantum-chemical electronic circular dichroism calculations or the modified Mosher's method. All the isolates were tested for α-glucosidase inhibitory activities. Compounds 1 and 3 displayed potent inhibitory activity against α-glucosidase with the IC50 values of 413.7 and 364.4 µM, respectively.

[Chemical constituents from Morinda citrifolia and their inhibitory activities on proliferation of synoviocytes in vitro].

The chemical constituents from the stems and leaves of Morinda citrifolia were isolated and purified by column chromatography methods with silica gel, ODS, Sephadex LH-20 and preparative high performance liquid chromatography(HPLC). The structures of the isolated compounds were identified by physicochemical properties and spectroscopic analysis, as well as comparisons with the data reported in literature. 17 compounds were isolated from the 90% ethanol extract of the stems and leaves of M. citrifolia, and were identified as 9,10-dihydroxy-4, 7-megastigmadien-3-one(1), 5,12-epoxy-6,9-hydroxy-7-megastigmen-3-one(2), fukinone(3), ß-eudesmol(4), sarmentol F(5), 4, 5-dihydroblumenol A(6), 3-hydroxy-ß-ionone(7), aristol-8-en-1-one(8), ergosta-7-en-3ß-ol(9), ergosta-7-ene-3ß,5α,6ß-triol(10),(22E)-5α,8α-epidioxyergosta-6,22-dien-3ß-ol(11), olivil(12), 4-epi-larreatricin(13), chushizisin Ⅰ(14), rabdosia acid A(15), glycerol monolinoleate(16) and(9Z,12Z,15Z)-2,3-dihydroxypropyl octadeca-trienoate(17). All compounds were isolated from M. citrifolia for the first time. All isolated compounds were evaluated for their anti-rheumatoid arthritis activities via examining their inhibitory activities on the proliferation of synoviocytes in vitro using MTS met-hod. Compounds 1-11 showed significant anti-rheumatoid arthritis activities, displaying the inhibitory effects on the proliferation of MH7 A synovial fibroblast cell with the IC_(50) values ranging from(38.69±0.86) to(203.45±1.03) µmol·L~(-1).

Phenolic glycosides from the stems of Homalium stenophyllum.

The phytochemical investigation of the stems of Homalium stenophyllum afforded seven new phenolic glycosides (1-5 and 8-9) and two known compounds (6 and 7). Their structures were elucidated by comprehensive analyses of NMR spectroscopic, mass spectrometric data and chemical hydrolysis. Additionally, their anti-inflammatory activities against the NO production in LPS-induced macrophages were evaluated.

Bioactive cyclohexene derivatives from a mangrove-derived fungus Cladosporium sp. JJM22.

Four new cyclohexene derivatives cladoscyclitols A-D (1-4) and one new ribofuranose phenol derivative 4-O-α-D-ribofuranose-2-pentyl-3-phemethylol (5) were obtained from the EtOAC extract of the mangrove-derived endophytic fungus Cladosporium sp. JJM22. The structures were elucidated by extensive NMR and MS analysis, while the absolute configurations of the stereogenic carbons were established based on quantum-chemical electronic circular dichroism calculations or comparison of the optical rotations with those of related compounds. Compounds 2 and 5 displayed potent inhibitory activity against α-glucosidase with the IC50 values of 2.95 and 2.05 µM, respectively.

Three new methylated Δ8-pregnene steroids from the Polyalthia laui-derived fungus Stemphylium sp. AZGP4-2.

Three new methylated Δ8-pregnene steroids, stemphylisteroids A-C (1-3) were isolated from the medicinal plant Polyalthia laui-derived fungus Stemphylium sp. AZGP4-2. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. The absolute configuration of 1 was determined by X-ray crystallographic analysis. Compound 1 show antibacterial activity against Escherichia coli with the MIC value of 6.25 µg/mL, and 2 exhibited a broad spectrum of antibacterial activities against six pathogenic bacteria with the MIC values ranging from 12.5 to 50 µg/mL. The discovery of three methylated Δ8-pregnene steroids 1-3 are a further addition to diverse and complex array of methylated steroids.

A new triterpenoid glucoside from Leucas zeylanica.

A new triterpenoid glucoside, leuctriterpencoside (1), along with two known compounds (2-3) were isolated from Leucas zeylanica. The structure of the new compound was elucidated using comprehensive spectroscopic methods. Compound 1 showed significant inhibitory activity against α-glucosidase (IC50 value of 0.85 ± 0.12 µM).

[Chemical constituents from fermented Noni juice].

The present work was launched to study the chemical constituents from fermented Noni juice. Ten compounds were isolated by using silicagel,Sephadex LH-20 and pre-HPLC. The structures of these compounds were identified by 1D and 2D NMR. Their structures were established as norimester( 1),cyclo( R-Pro-S-Phe)( 2),cyclo-( L-Pro-L-Leu)( 3),trans-cyclo-( D-tryptophanyl-Ltyrosyl)( 4),cyclo( L-Trp-N-methyl-L-Ala-)( 5),4-allyl-2-hydroxyphenyl 1-O-ß-D-apiosyl-( 1 → 6)-ß-D-glucopyranoside( 6),2-methoxy-4-vinylphenyl ß-D-apiofuranosyl-( 1→6)-ß-D-glucopyranoside( 7),( +)-lirioresinol A( 8),( ±)-syringaresinol( 9),and2-formyl-1 H-pyrrole-1-butanoic acid( 10). All compounds were tested for their antibacterial activity and α-glucosidase inhibitory activity. Compound 1 was a new compound. All compounds were isolated from fermented Noni juice for the first time. Compound 1 showed significant inhibitory activity against α-glucosidase [IC50 value of( 4. 22±0. 03) µmol·L-1].

Bioactive acetaminophen derivatives from Penicillum herquei JX4.

Two novel epimer pairs of acetaminophen derivatives penicilquei A-D (1-4) were isolated from Penicillium herquei JX4. Their structures were elucidated using comprehensive spectroscopic methods. The absolute configurations of penicilquei A-D (1-4) were determined by modifified Mosher's method, and comparing their experimental and calculated electronic circular dichroism (ECD) spectra. Penicilquei A-D (1-4) are the first example of acetaminophen derivatives featuring an unprecedented carbon skeleton. The inhibitory activities of all compounds against nine phytopathogenic fungi and α-glucosidase were evaluated. Penicilquei A-D (1-4) showed strong inhibitory activities against at least eight phytopathogenic fungus.