Two cyclopeptides, celogentin L (1) and its epimer lyciumin A (2) were firstly isolated from Celosia argentea L.. The planar structures of the two compounds were fully determined by spectroscopic data, including 1D-, 2D-NMR, and HR-ESI/MS. The absolute configurations of amino acid components were assigned via chiral-phase HPLC analyses after acid hydrolysis. Furthermore, the configuration of C-N linkage at the glycine Cα was elucidated by extensive analyses of 2D-NMR and comparison of the experimental and calculated electronic circular dichroism (ECD) spectra. Cytotoxicity of the two compounds against human alveolar epithelial A549, hepatocellular carcinoma HepG2, and cervical cancer Hela cell lines was assayed. Although both of them were inactive in these cells, the present findings add new facets for the chemistry of Celosia argentea.
A549 Cells ; Cell Survival ; drug effects ; Celosia ; chemistry ; Chemistry Techniques, Analytical ; HeLa Cells ; Hep G2 Cells ; Humans ; Molecular Conformation ; Molecular Structure ; Peptides, Cyclic ; chemistry ; isolation & purification ; toxicity ; Seeds ; chemistry ; Stereoisomerism

To study the secondary metabolites of a marine-derived fungus Ascotricha sp. ZJ-M-5, several chromatographic methods including macroporous resin, silica gel, ODS and Sephadex LH-20 were used to isolate the compounds, and their structures were elucidated on the basis of physicochemical properties and spectroscopic methods. Ten compounds were obtained and identified as ascotrichic acid B (1), (3R)-6-hydroxymellein (2), beta-carboline (3), (22E, 24R)-ergosta-7, 22-diene-3beta, 5alpha, 6beta-triol (4), (22E, 24R)-ergosta-7, 22-diene-3beta, 5alpha, 6beta, 9alpha-tetraol (5), cyclo (Leu-Pro) (6), cyclo (Ile-Leu) (7), cyclo (Pro-Val) (8), cyclo (Pro-Gly) (9), and cyclo (Hpro-Ala) (10). Among them, compound 1 is a new 3, 4-seco-lanostane triterpenoid which has been isolated from the filamentous fungi for the first time, and compounds 2-10 are firstly isolated from Ascotricha genus.
Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Ascomycota ; chemistry ; Carbolines ; chemistry ; isolation & purification ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Dipeptides ; chemistry ; isolation & purification ; pharmacology ; Drug Screening Assays, Antitumor ; Humans ; Lanosterol ; analogs & derivatives ; chemistry ; isolation & purification ; pharmacology ; Molecular Structure ; Peptides, Cyclic ; chemistry ; isolation & purification ; pharmacology

Antimicrobial Cationic Peptides ; biosynthesis ; genetics ; DNA-Binding Proteins ; biosynthesis ; genetics ; Humans ; Microbial Sensitivity Tests ; Muramidase ; biosynthesis ; genetics ; Peptides, Cyclic ; biosynthesis ; genetics ; Pichia ; metabolism ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification

OBJECTIVETo separate and identify cyclopeptides of tubers of Rubia schumanniana.

METHODThe 70% methanol extracts from tubers of Rubia schumanniana were separated and purified by silica gel, RP-18, Sephedax LH-20 and HPLC. Their structures were identified by spectral analysis.

RESULTNine cyclopeptides were separated and identified as RA- II (1), RA-V (2), RA-VIII (3), rubiyunnanin C (4), RA-X (5), RY-II (6), RA- I (7), RA-XIII (8) and RA-XIII-OMe (9), respectively.

CONCLUSIONAll of nine cyclopeptides were separated from R. schumanniana for the first time.

Drugs, Chinese Herbal ; chemistry ; isolation & purification ; Molecular Structure ; Peptides, Cyclic ; analysis ; isolation & purification ; Rubia ; chemistry

In order to study the chemical constituents of the leaves of Tripterygium wilfordii and provide references for the bio-active study, we isolated nine compounds from the dried leaves of Tripterygium wilfordii. Their structures were determined by application of spectroscopic (NMR, MS) and chemical methods. These compounds were isolated and identified as (+)-lyoniresinol (1), (+)-isolariciresinol (2), burselignan (3), dibutyl phthalate (4), cyclo-(S-Pro-R-Phe) (5), cyclo-(S-Pro-R-Leu) (6), cyclo-(S-Pro-S-Ile) (7), 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone (8) and daucosterol (9). Compounds 1-3, 5-8 were isolated from this plant for the first time.
Anisoles ; chemistry ; isolation & purification ; Dibutyl Phthalate ; chemistry ; isolation & purification ; Lignin ; chemistry ; isolation & purification ; Magnetic Resonance Imaging ; methods ; Mass Spectrometry ; methods ; Naphthalenes ; chemistry ; isolation & purification ; Naphthols ; chemistry ; isolation & purification ; Peptides, Cyclic ; chemistry ; isolation & purification ; Plant Extracts ; chemistry ; isolation & purification ; Plant Leaves ; chemistry ; Sitosterols ; chemistry ; isolation & purification ; Tripterygium ; chemistry

Cyclic lipopeptide, also named as acylpeptide, which was characteristic with novel structures, was paid more attention in the recent years. Cyclic lipopeptide showed various bioactivities including antibacterial, anti-tumor, anti-inflammatory, etc. Cyclic lipopeptide originated mainly from the second metabolites of microorganism, such as Cyanobacterium, Bacterium, Actinomyces, etc. The bacteria included the genus of Bacillus and Pseudomonas. In this account, the review has been made on the development of cyclic lipopeptide.
Anti-Bacterial Agents ; pharmacology ; Antibiotics, Antineoplastic ; pharmacology ; Bacillus ; chemistry ; Cyanobacteria ; chemistry ; Daptomycin ; isolation & purification ; pharmacology ; Humans ; Lipopeptides ; chemistry ; isolation & purification ; pharmacology ; Peptides, Cyclic ; chemistry ; isolation & purification ; pharmacology ; Pseudomonas ; chemistry

As the technologies of separation, purification and determination develop rapidly, more and more peptide compounds, which have special bioactive and medical value, have been separated from natural plants, such as oligopeptides and cyclopeptides. The chemical structures and function of these plant peptides have been researched profoundly. This paper mainly reviews the composition, structure, bioactive function and medicine value of representative plant peptides in recent years, and can give some references about research and application of plant bioactive peptides.
Animals ; Antihypertensive Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents, Phytogenic ; chemistry ; isolation & purification ; pharmacology ; Antioxidants ; chemistry ; isolation & purification ; pharmacology ; Glutathione ; chemistry ; isolation & purification ; pharmacology ; Gramicidin ; chemistry ; isolation & purification ; pharmacology ; Humans ; Hypoglycemic Agents ; chemistry ; isolation & purification ; pharmacology ; Oligopeptides ; chemistry ; isolation & purification ; pharmacology ; Peptides ; chemistry ; isolation & purification ; pharmacology ; Peptides, Cyclic ; chemistry ; isolation & purification ; pharmacology ; Plants ; chemistry ; Plants, Medicinal ; chemistry

AIMTo isolate IL-6R antagonists from the cultured broth of the strain Torulomyces ovatus.

METHODSVarious column chromatographyes were used to separate and purify the compounds with IL-6R antagonist activity. The spectral data and physic-chemical properties were measured for structure identification.

RESULTSOne compound namely 2520 was isolated from the cultured broth of Torulomyces ovatus.

CONCLUSION2520A is a known compound (ferrichrome). It is first reported about its antagonistic activity of IL-6R and identification of iron atom in its structure.

Anti-Bacterial Agents ; chemistry ; isolation & purification ; pharmacology ; Antineoplastic Agents ; chemistry ; isolation & purification ; pharmacology ; Bacillus subtilis ; drug effects ; Cell Line, Tumor ; Cell Survival ; drug effects ; Fermentation ; Ferric Compounds ; chemistry ; isolation & purification ; pharmacology ; Ferrichrome ; chemistry ; isolation & purification ; pharmacology ; Humans ; Mitosporic Fungi ; chemistry ; Molecular Structure ; Peptides, Cyclic ; chemistry ; isolation & purification ; pharmacology ; Receptors, Interleukin-6 ; antagonists & inhibitors

Platelet aggregation was inhibited and the density of platelet-rich plasma (PRP) clots was decreased by the preincubation of PRP with surfactins, an acidic lipopeptide of Bacillus subtilis complex BC1212 isolated from soybean paste, in dose-dependent manner. Our findings suggest that surfactins are able to prevent a platelet aggregation leading to an inhibition of additional fibrin clot formation, and to enhance fibrinolysis with facilitated diffusion of fibrinolytic agents.
Bacillus subtilis/metabolism ; Blood Platelets/drug effects ; Fibrinolytic Agents/*pharmacology ; Humans ; Peptides, Cyclic/isolation&purification/*pharmacology ; Platelet Aggregation Inhibitors/pharmacology

Protein splicing is a newly discovered posttranslational editing process that removes an internal protein fragment from the protein precursor. During the splicing process the internal protein fragment, intein, triggered the self-excision from the precursor protein and the concomitant ligation of the flanking protein fragments, exteins. The self-catalysis requires neither auxiliary enzymes nor cofactors and only involves four intramolecular reactions. A number of key catalytic residues in inteins and flanking fragments have been identified, which led to the development of the protein splicing process as a protein engineering tool. Controllable cleavage of the peptide bond at either the N or the C terminus of an intein has allowed the design of novel strategies for manipulation of protein and peptides. Affinity purification of recombinant proteins can be facilitated by fusion the target protein with an intein. The fusion also creates C-terminal thioester, which expands the scope of chemical ligation in protein. Inteins can be engineered in a "split and inverted" configuration to form a cyclic polypeptide consisting of the sequence linking two intein subdomains. This article summarizes the recent advance in the mechanism of protein splicing and its applications in protein purification, protein ligation and protein cyclization.
Inteins ; genetics ; physiology ; Peptides, Cyclic ; genetics ; isolation & purification ; metabolism ; Protein Engineering ; methods ; Protein Splicing ; genetics ; physiology ; Proteins ; genetics ; isolation & purification ; metabolism