Four new polyhydroxylated steroids from the South Sea sponge Plakortis sp.

Four new polyhydroxylated steroids plaksterols A-D (1-4), together with two known related steroids ergost-7,9(11),22-trien-3ß,5α,6α-triol (5) and ergosta-6ß-methoxy-7,22-diene-3ß,5α-diol (6), were isolated from methanol extract of the South China Sea marine sponge Plakortis sp. Their structures were identified by spectroscopic analysis, including NMR, MS, and IR. The cytotoxicity of the polyhydroxylated steroids were evaluated, and compound 6 showed moderate inhibitory activities against K562, HL-60 and BEL-7402 cells.

Cytotoxic and Antiviral Triterpenoids from the Mangrove Plant Sonneratia paracaseolaris.

A chemical investigation was conducted on the aerial parts of the mangrove plant Sonneratia paracaseolaris, yielding five new triterpenoid paracaseolins A-E (1-4, and 11) together with twelve known analogues (5-10, 12-17). Their structures were established by extensive spectroscopic methods and comparisons their spectroscopic data with those of the known related compounds. The cytotoxicities against P388, HeLa, A549, and K562 tumor cell lines and anti-H1N1 (Influenza A virus) activities for the isolates were evaluated. Compound 4 showed potent cytotoxicity against the A549 cell line with an IC50 value of 1.89 µM, and compound 1 exhibited significant anti-H1N1 virus activity with an IC50 value of 28.4 µg/mL. A preliminary structure activity relationship was discussed.

Six New Acylphloroglucinols from Dryopteris championii.

Six new acylphloroglucinols (1 - 6) were isolated from Dryopteris championii. Their structures were established on the basis of extensive analysis of spectroscopic data and comparison with reported data. The antibacterial activities of the isolates were evaluated against Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Dickeya zeae.

Nano-LC-ESI MS/MS analysis of proteins in dried sea dragon Solenognathus hardwickii and bioinformatic analysis of its protein expression profiling.

The sea dragon Solenognathus hardwickii has long been used as a traditional Chinese medicine for the treatment of various diseases, such as male impotency. To gain a comprehensive insight into the protein components of the sea dragon, shotgun proteomic analysis of its protein expression profiling was conducted in the present study. Proteins were extracted from dried sea dragon using a trichloroacetic acid/acetone precipitation method and then separated by SDS-PAGE. The protein bands were cut from the gel and digested by trypsin to generate peptide mixture. The peptide fragments were then analyzed using nano liquid chromatography tandem mass spectrometry (nano-LC-ESI MS/MS). 810 proteins and 1 577 peptides were identified in the dried sea dragon. The identified proteins exhibited molecular weight values ranging from 1 900 to 3 516 900 Da and pI values from 3.8 to 12.18. Bioinformatic analysis was conducted using the DAVID Bioinformatics Resources 6.7 Gene Ontology (GO) analysis tool to explore possible functions of the identified proteins. Ascribed functions of the proteins mainly included intracellular non-membrane-bound organelle, non-membrane-bounded organelle, cytoskeleton, structural molecule activity, calcium ion binding and etc. Furthermore, possible signal networks of the identified proteins were predicted using STRING (Search Tool for the Retrieval of Interacting Genes) database. Ribosomal protein synthesis was found to play an important role in the signal network. The results of this study, to best of our knowledge, were the first to provide a reference proteome profile for the sea dragon, and would aid in the understanding of the expression and functions of the identified proteins.

Dimeric Matrine-Type Alkaloids from the Roots of Sophora flavescens and Their Anti-Hepatitis B Virus Activities.

Six unusual matrine-type alkaloid dimers, flavesines A-F (1-6, respectively), together with three proposed biosynthetic intermediates (7-9) were isolated from the roots of Sophora flavescens. Compounds 1-5 were the first natural matrine-type alkaloid dimers, and compound 6 represented an unprecedented dimerization pattern constructed by matrine and (-)-cytisine. Their structures were elucidated by NMR, MS, single-crystal X-ray diffraction, and a chemical method. The hypothetical biogenetic pathways of 1-6 were also proposed. Compounds 1-9 exhibited inhibitory activities against hepatitis B virus.

Induction of apoptosis in human leukemia cells through an intrinsic pathway by cathachunine, a unique alkaloid isolated from Catharanthus roseus.

BACKGROUND: Catharanthus roseus (L.) G. Don consists of a range of dimeric indole alkaloids with significant antitumor activities. These alkaloids have been found to possess apoptosis-inducing activity against tumor cells in vitro and in vivo mediated by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and c-Jun N-terminal kinase (JNK) pathways, in which DNA damage and mitochondrial dysfunction play important roles. In this study, a unique bisindole alkaloid named cathachunine, along with five known dimeric indole alkaloids, was obtained from C. roseus and investigated in vitro. PURPOSE: The aim of this study was to investigate the antitumor activity of isolated alkaloids and the mechanism through which cathachunine exerts its antitumor effect. STUDY DESIGN AND METHODS: Cell growth inhibition was assessed by WST-1 and lactate dehydrogenase (LDH) assays in HL60, K562 leukemia cells and EA.hy926 umbilical vein cells. Induction of apoptosis in HL60 cells was confirmed by observation of nuclear morphology, a caspase-3 activity assay and annexin V-fluorescein isothiocyanate/propidium iodide (FITC/PI) double staining. The intrinsic apoptotic pathway induced by cathachunine was evidenced by B-cell lymphoma 2/Bcl-2-associated X protein (Bcl-2/Bax) dysregulation, loss of mitochondrial membrane potential, translocation of cytochrome c, and cleavage of caspase-3 and poly-ADP ribose polymerase (PARP). Reactive oxygen species (ROS) production after cathachunine treatment was determined by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining. Cell cycle arrest of the S phase was also observed in HL60 cells after cathachunine treatment. RESULTS: The WST-1 and LDH assays showed that Catharanthus alkaloids were cytotoxic toward human leukemia cells to a greater extent than toward normal human endothelial cells, and the anti-proliferation and pro-apoptosis abilities of cathachunine were much more potent than other previously reported alkaloids. The induction of apoptosis by cathachunine occurred through an ROS-dependent mitochondria-mediated intrinsic pathway rather than an extrinsic pathway, and was regulated by the Bcl-2 protein family. CONCLUSION: An unprecedented bisindole alkaloid cathachunine which lost C-18' and C-19' was isolated from C. roseus. It exerted a potent antitumor effect toward human leukemia cells through the induction of apoptosis via an intrinsic pathway. Thus, this study provides evidence for a new lead compound from a natural source for anti-cancer investigations.

Chinese Marine Materia Medica Resources: Status and Potential.

Chinese marine materia medica (CMMM) is a vital part of traditional Chinese medicine (TCM). Compared with terrestrial TCM, CMMM, derived from specific marine habitats, possesses peculiar chemical components with unique structures reflecting as potent pharmacological activities, distinct drug properties and functions. Nowadays, CMMM appears to be especially effective in treating such difficult diseases as cancers, diabetes, cardio-cerebrovascular diseases, immunodeficiency diseases and senile dementia, and therefore has become an important medicinal resource for the research and development of new drugs. In recent years, such development has attracted wide attention in the field of medicine. In this study, the CMMM resources in China were systematically investigated and evaluated. It was found that the historic experiences of Chinese people using CMMM have continuously accumulated over a period of more than 3600 years, and that the achievements of the research on modern CMMM are especially outstanding. By June 2015, 725 kinds of CMMMs from Chinese coastal sea areas have been identified and recorded, covering 1552 organisms and minerals. More than 3100 traditional prescriptions containing CMMMs have been imparted and inherited. However, the number of CMMMs is less than the 8188 terrestrial TCMs, from more than 12,100 medicinal terrestrial plants, animals and minerals. In the future, the research and development of CMMM should focus on the channel entries (TCM drug properties), compatibility, effective ingredients, acting mechanisms, drug metabolism and quality standard. This study reveals the high potential of CMMM development.

Phenolic Compounds from the Flowers of Bombax malabaricum and Their Antioxidant and Antiviral Activities.

Three new phenolic compounds 1-3 and twenty known ones 4-23 were isolated from the flowers of Bombax malabaricum. Their chemical structures were elucidated by spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D- and 2D-NMR) and chemical reactions. The antioxidant capacities of the isolated compounds were tested using FRAP and DPPH radical-scavenging assays, and compounds 4, 6, 8, 12, as well as the new compound 2, exhibited stronger antioxidant activities than ascorbic acid. Furthermore, all of compounds were tested for their antiviral activities against RSV by the CPE reduction assay and plaque reduction assay. Compounds 4, 10, 12 possess in vitro antiviral activities, and compound 10 exhibits potent anti-RSV effects, comparable to the positive control ribavirin.

New Phloroglucinol Derivatives from the Fruit Tree Syzygium jambos and Their Cytotoxic and Antioxidant Activities.

Seven new phloroglucinol derivatives (1-7) were isolated from the fruit tree Syzygium jambos together with four known triterpenoids (8-11) and two known flavones (12 and 13). According to the spectroscopic analyses (infrared, electrospray ionization mass spectrometry (ESIMS), high-resolution ESIMS, 1D and 2D nuclear magnetic resonance), the structures of compounds 1-7 were elucidated as jambone A (1), jambone B (2), jambone C (3), jambone D (4), jambone E (5), jambone F (6), and jambone G (7). All the isolates were determined for their cytotoxic activities on melanoma cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and compounds 10 and 11 showed potent activities. Moreover, compounds 1, 2, 4-7, 12, and 13 exhibited weak antioxidant activities under ferric-reducing antioxidant power and 2,2-diphenyl-1-picryhydrazyl radical-scavenging assays.

Grape seed proanthocyanidin protects liver against ischemia/reperfusion injury by attenuating endoplasmic reticulum stress.

AIM: To explore the effect of grape seed proanthocyanidin (GSP) in liver ischemia/reperfusion (IR) injury and alleviation of endoplasmic reticulum stress. METHODS: Male Sprague-Dawley rats (220-250 g) were divided into three groups, namely, sham, IR, and GSP groups (n = 8 each). A liver IR (70%) model was established and reperfused for 6 h. Prior to reperfusion, the GSP group was administered with GSP (100 mg/kg) for 15 d, and liver histology was then investigated. Serum aminotransferase and inflammatory mediators coupled with superoxide dismutase and methane dicarboxylic aldehyde were detected. Western blot was conducted to analyze the expression of glucose-regulated protein 78, CCAAT/enhancer-binding protein homologous protein, activating transcription factor-4, inositol-requiring enzyme-1, procaspase-12, and nuclear factor-κb. Apoptotic cells were detected by TUNEL staining. RESULTS: The serum aminotransferase, apoptotic cells, and Suzuki scores decreased in the GSP group compared with the IR group (Ps < 0.05). The methane dicarboxylic aldehyde level was decreased in the GSP group, but the superoxide dismutase level was reversed (Ps < 0.05). Similarly, GSP downregulated the proinflammatory factors and upregulated the levels of anti-inflammatory factors (Ps < 0.05). Western blot data showed that GSP increased glucose-regulated protein 78 expression and suppressed expression of CCAAT/enhancer-binding protein homologous protein, activating transcription factor-4, inositol-requiring enzyme-1, procaspase-12, and nuclear factor-κb compared with the IR group. CONCLUSION: GSP possesses antioxidative, anti-inflammatory, and antiapoptotic effects by relieving endoplasmic reticulum stress through regulation of related signaling pathways to protect the liver against IR injury.

Two New Oxindole Alkaloid Glycosides from the Leaves of Nauclea officinalis.

Two new oxindole alkaloid glycosides, nauclealomide A and (3S,7R)-javaniside, were isolated from the leaves of Nauclea officinalis. Their structures and absolute configurations were elucidated by means of NMR, HRESIMS, X-ray diffraction, acid hydrolysis and quantum chemical CD calculation. Nauclealomide A is a novel monoterpenoid oxindole alkaloid possessing a rare tetrahydro-2H-1,3-oxazine ring.

Cytotoxic rotenoid glycosides from the seeds of Amorpha fruticosa.

Four new rotenoid glycosides, namely amorphaside A-D (1-4), along with four known ones (5-8) were isolated from the seeds of Amorpha fruticosa. Their chemical structures and absolute configurations were elucidated by HRESIMS, NMR and CD spectra, as well as deduction from biosynthesis route. The sugar units were determined by acid hydrolysis, appropriate derivatization and HPLC analysis. The in vitro anti-proliferative activities of all compounds were evaluated against MCF-7 and HCT-116 cell lines. The results showed that compounds 1-3 had no effect on cell proliferation in the two cell lines even with the concentration of 50 µM, and compounds 4, 7 and 8 had selective cytotoxicity against MCF-7 with IC50 values of 3.90, 0.95 and 34.08 µM, respectively, while compounds 5 and 6 both showed significant cytotoxicity to the two cell lines with IC50 values less than 2.00 µM, even better than the positive control cisplatin. These preliminary results indicated that compounds 5 and 6 might be valuable to anticancer drug candidates.

[Chemical constituents from Glechoma longituba].

Fourteen compounds were obtained from Glechoma longituba by the chromatographic methods of silica gel, ODS, Sephadex LH-20 and preparative of HPLC. According to physicochemical properties and spectral data, these compounds were identified as stilbostemin B (1), trilepisiumic acid (2), 3, 4-dihydroxyphenyl ethanol ketone (3), bergeninmonohydrate (4), oresbiusin A (5), norbergenin (6), stilbostemin D (7), ehretioside B (8), ethyl ferulate (9), E-p-hydroxy-cinnamic acid (10), methyl gallate (11), protocatechuic acid (12), 4'-Hydroxyacetophenone (13), and E-3-2,4-dihydroxyphenyl-2-acrylic acid (14). Among them, compounds 1-10, 13 and 14 were isolated from this plant for the first time.

Iboga-Type Alkaloids from Ervatamia officinalis.

Seven new iboga-type alkaloids, ervaoffines A-D (1-4), (7S)-3-oxoibogaine hydroxyindolenine (5), ibogaine-5,6-dione (6), and 19-epi-5-oxovoacristine (7), and 10 known alkaloids were isolated from Ervatamia officinalis. The absolute configurations of 1-7 were determined through X-ray diffraction and electronic circular dichroism (ECD) analyses. Ervaoffines A and B represent the first iboga-type pseudoindoxyl alkaloids in which the C-2 spiro carbon configuration is opposite to that of other members of this class, such as iboluteine (8). The relationship between the absolute configuration of the spiro carbons and the Cotton effect in the ECD spectrum is established for the first time for iboga-type pseudoindoxyl and oxindole alkaloids. Additionally, a plausible biogenetic pathway for these alkaloids is proposed.

Cycloartane triterpenoids and their glycosides from the rhizomes of Cimicifuga foetida.

A phytochemical study on the rhizomes of Cimicifuga foetida resulted in the isolation of two new cycloartane triterpenoids (1 and 2), eight new cycloartane glycosides (3-10), and six known cycloartane glycoside analogues (11-16). The structures of 1-10 were determined by application of spectroscopic methods, with the absolute configuration of 1 determined by X-ray crystallography. Compounds 1-6, as three pairs of epimers at C-10 and C-24, belong to a seven-membered-ring variant of 9,10-seco-9,19-cycloartane triterpenoids, and glycosides 3-10 were found to be 3-O-ß-D-xylopyranosides. The cytotoxicity of the isolates was evaluated against five selected human tumor cell lines, and the known compounds 15 and 16 showed cytotoxicity against the hepatocellular carcinoma SMMC-7721 cell line with IC50 values of 5.5 and 6.3 µM, respectively.

A new diterpenoid from the aerial parts of Andrographis paniculata.

One new and seven known diterpenoids were isolated from the aerial parts of Andrographis paniculata, and their structures elucidated on the basis of spectroscopic and spectrometric analysis, as well as chemical methods. The in vitro antiviral activities of these compounds against respiratory syncytial virus (RSV) were assayed.

Antiviral activity of polymethoxylated flavones from "Guangchenpi", the edible and medicinal pericarps of citrus reticulata 'Chachi'.

The present study found that the supercritical fluid extract of "Guangchenpi" possessed in vitro antiviral activity against respiratory syncytial virus (RSV). Bioassay-guided isolation and identification of this extract led to obtain five active polymethoxylated flavones (1-5). Cytopathic effect (CPE) reduction assay exhibited that tangeretin (2) and nobiletin (3), two major polymethoxylated flavones in the extract, possessed better anti-RSV effect comparable to the positive control ribavirin. Plaque reduction assay revealed that tangeretin dose-dependently inhibited RSV-induced plaque formation on the HEp-2 cells. This polymethoxylated flavone mainly affected the intracellular replication of RSV, and it also could inhibit RSV entry into the HEp-2 cells. Further investigations with quantitative real-time PCR and confocal and Western blot assays indicated that tangeretin downregulated the expression of RSV phosphoprotein (P protein). Results suggest the potential application of the supercritical fluid extract of "Guangchenpi" and tangeretin in the treatment and the prevention of RSV infection.

Phenolic compounds from Origanum vulgare and their antioxidant and antiviral activities.

In the present study, six new phenolic compounds (1-6) along with five known ones were isolated from the ethanol extract of the whole plants of Origanum vulgare. The structures of the new compounds were identified on the basis of extensive spectroscopic analyses (UV, IR, NMR, and HRESIMS) and acid hydrolysis. Twenty-one phenolic compounds isolated from O. vulgare in our previous and present studies were evaluated for their in vitro antioxidant activity using 2,2-diphenyl-1-picryhydrazyl (DPPH) radical-scavenging and ferric-reducing antioxidant power (FRAP) assays; twelve of them including two new compounds exhibited significant antioxidant activity comparable to that of ascorbic acid. In addition, the antiviral effects against respiratory syncytial virus (RSV), Coxsackie virus B3 (CVB3) and herpes simplex virus type 1 (HSV-1) were tested by cytopathic effect (CPE) reduction assay.

Dynamic processes of indigenous microorganisms from a low-temperature petroleum reservoir during nutrient stimulation.

Compared to medium-high temperature petroleum reservoirs (30°C-73°C), little is known about microbial regulation by nutrients in low-temperature reservoirs. In this study, we report the performance (oil emulsification and biogas production) and community structure of indigenous microorganisms from a low-temperature (22.6°C) petroleum reservoir during nutrient stimulation. Culture-dependent approaches indicated that the number of hydrocarbon-oxidizing bacteria (HOB), nitrate-reducing bacteria (NRB) and methane-producing bacteria (MPB) increased by between 10- and 1000-fold, while sulfate-reducing bacteria (SRB) were observed at low levels during stimulation. Phylogenetic analysis of the 16S rRNA gene indicated that Pseudomonas, Ochrobactrum, Acinetobacter, Halomonas and Marinobacter, which have the capability to produce surfactants, were selectively enriched. Methanoculleus, Methanosaeta, Methanocorpusculum and Methanocalculus showed the largest increase in relative abundance among archaea. Micro-emulsion formed with an average oil droplet diameter of 14.3 µm (ranging between 4.1 µm and 84.2 µm) during stimulation. Gas chromatographic analysis of gas production (186 mL gas/200 mL medium) showed the levels of CO2 and CH4 increased 8.97% and 6.21%, respectively. Similar to medium-high temperature reservoirs, HOB, NRB, SRB and MPB were ubiquitous in the low-temperature reservoir, and oil emulsification and gas production were the main phenomena observed during stimulation. Oil emulsification required a longer duration of time to occur in the low-temperature reservoir.