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1.
The methanolic extract of Myrsine seguinii yielded the novel anti-inflammatory compound, myrsinoic acid E (1), whose structure was elucidated to be 3,5-digeranyl-4-hydroxy benzoic acid. We synthesized 1- and its 3,5-diprenyl (2) and 3,5-difarnesyl analogues (3). Compounds 1-3 suppressed 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation of mouse ears by 59%, 14%, and 69% at a dose of 1.4 micromol.  相似文献   

2.
The methanolic extract of Myrsine seguinii yielded the novel anti-inflammatory compound, myrsinoic acid E (1), whose structure was elucidated to be 3,5-digeranyl-4-hydroxy benzoic acid. We synthesized 1- and its 3,5-diprenyl (2) and 3,5-difarnesyl analogues (3). Compounds 1-3 suppressed 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation of mouse ears by 59%, 14%, and 69% at a dose of 1.4 μmol.  相似文献   

3.
A methioninase inhibitor from Myrsine seguinii was purified and identified as myrsinoic acid B. Its inhibitory activities as to crude methioninase from periodontal bacteria such as Fusobacterium nucleatum, Porphyromonas gingivalis, and Treponema denticola were determined. The IC50 values were 10.5, 82.4, and 30.3 microM respectively.  相似文献   

4.
A methioninase inhibitor from Myrsine seguinii was purified and identified as myrsinoic acid B. Its inhibitory activities as to crude methioninase from periodontal bacteria such as Fusobacterium nucleatum, Porphyromonas gingivalis, and Treponema denticola were determined. The IC50 values were 10.5, 82.4, and 30.3 μM respectively.  相似文献   

5.
To detect the flavor quality and flavor compounds in raw longissimus muscle from four typical pig breeds: Sus scrofa?×?Bamei pig named F1 (group A), F1?×?F1 (group B), F1?×?Bamei pig (group C), and F1?×?Large White (group D). The chemical compositions of longissimus muscles from four breeds were examined using headspace solid-phase microextraction/gas chromatography mass spectrometry method. Distinct differences for the same flavor compounds of longissimus muscles between different breeds were analyzed. Totally 64 flavor compounds shared in four groups, and 10 flavor compounds with significant difference among four groups (p?<?0.05), including allyl butyrate, (Z)-2-penten-1-ol, 2,2-dimethyl-3-methyl oxirane, 2-pentylfuran, dodecane, 2,4-decadienal, vinylsilane, 3-methyl-1-butanol, (1-methyldecyl)-benzene, and dipropyl phthalate. Totally, 23–41 flavor compounds did not commonly exist in four groups, such as only as dibutyl isophthalate in group A; 6,10-dimethyl-5-9-undecadien-2 one, bis (2-trimethylsilyl) ethyl ester-malonic acid, heptadecane, 2,4,6-trimethyl pyridine, and diisooctyl adipate in group C alone; and 1,3-dimethylcyclopentanol, 2-octanone, and trimethylsilane in group D alone. While, no specific flavor compounds were identified in group B. All these flavor compounds covered 12 types of hydrocarbons, alcohols, aldehydes, hydroxybenzenes, acids, ketones, esters, sulfides, furans, alkenes, and pyrrole. Besides, we analyzed 14 flavor compounds with different flavors combining with previous studies. The flavor compounds in longissimus muscles might be closely related to the breeds, and the hybrid of S. scrofa?×?Bamei pig had the most flavor compounds in raw longissimus muscle.  相似文献   

6.
F2-isoprostanes are prostaglandin F2-like compounds that are formed nonenzymatically by free radical mediated peroxidation of arachidonic acid. Intermediate in the pathway of the formation of isoprostanes are labile prostaglandin H2-like bicyclic endoperoxides (H2-isoprostanes), which are reduced to F2-isoprostanes and also undergo rearrangement in vivo to form E-ring and D-ring isoprostanes, isothromboxanes, and highly reactive acyclic gamma-ketoaldehdyes (isoketals). Docosahexaenoic acid (C22:6omega3) is highly enriched in neurons in the brain and is highly susceptible to oxidation. Free radical mediated oxidation of docosahexaenoic acid results in the formation of isoprostane-like compounds (neuroprostanes). F4- and E4/D4-neuroprostanes as well as neuroketals have been shown to be produced in vivo. Finally, we recently discovered a new pathway of lipid peroxidation that forms compounds with a substituted tetrahydrofuran ring (isofurans). Oxygen concentrations differentially modulate the formation of isoprostanes and isofurans; at elevated oxygen concentrations, the formation of isofurans is favored whereas the formation of isoprostanes is disfavored.  相似文献   

7.
Environmental compounds are known to promote epigenetic transgenerational inheritance of adult onset disease in subsequent generations (F1–F3) following ancestral exposure during fetal gonadal sex determination. The current study was designed to determine if a mixture of plastic derived endocrine disruptor compounds bisphenol-A (BPA), bis(2-ethylhexyl)phthalate (DEHP) and dibutyl phthalate (DBP) at two different doses promoted epigenetic transgenerational inheritance of adult onset disease and associated DNA methylation epimutations in sperm. Gestating F0 generation females were exposed to either the “plastics” or “lower dose plastics” mixture during embryonic days 8 to 14 of gonadal sex determination and the incidence of adult onset disease was evaluated in F1 and F3 generation rats. There were significant increases in the incidence of total disease/abnormalities in F1 and F3 generation male and female animals from plastics lineages. Pubertal abnormalities, testis disease, obesity, and ovarian disease (primary ovarian insufficiency and polycystic ovaries) were increased in the F3 generation animals. Kidney and prostate disease were only observed in the direct fetally exposed F1 generation plastic lineage animals. Analysis of the plastics lineage F3 generation sperm epigenome previously identified 197 differential DNA methylation regions (DMR) in gene promoters, termed epimutations. A number of these transgenerational DMR form a unique direct connection gene network and have previously been shown to correlate with the pathologies identified. Observations demonstrate that a mixture of plastic derived compounds, BPA and phthalates, can promote epigenetic transgenerational inheritance of adult onset disease. The sperm DMR provide potential epigenetic biomarkers for transgenerational disease and/or ancestral environmental exposures.  相似文献   

8.
The relationship between the structure and function of a series of nicotinic cholinergic agonists has been studied using radioligand binding, single channel recording, and nuclear magnetic resonance spectroscopy. The cyclic compound 1,1-dimethyl-4-acetylpiperazinium iodide and its trifluoromethyl analogue (F3-PIP) interact with nicotinic acetylcholine receptors (nAChRs) from both Torpedo electroplaque and BC3H-1 cells at lower concentrations than the acyclic derivatives, N,N,N,N'-tetramethyl-N'-acetylethylenediamine iodide and its fluorinated analogue (F3-TED). The magnitude of the difference in potencies depends on the type of measurement. In binding experiments, the differences between the two classes of compounds depends mainly on the conditions of the experiment. In measurements of the initial interaction with the nAChR, the PIP compounds have an affinity approximately one order of magnitude higher than that of the TED compounds. Longer incubations indicated that the PIP compounds were able to induce a time-dependent shift in receptor affinity consistent with desensitization, whereas the TED compounds were unable to induce such a shift. The activation of single channel currents by the cyclic compounds occurs at concentrations approximately two orders of magnitude lower than for the acyclic compounds, but the TED compounds exhibit a larger degree of channel blockade than the PIP compounds. Previous work (McGroddy, K.A., and R.E. Oswald. 1992. Biophys. J. 64:314-324) has shown that the TED compounds can exist in two energetically distinct conformational states related by an isomerization of the amide bond. 19F nuclear magnetic resonance experiments suggest that the higher energy population of the TED compounds may interact preferentially with the ACh binding sites on the nAChRs and that a significant fraction of the difference between the initial affinity of the PIP and TED compounds may be accounted for by the predominance in solution of a conformational state less able to interact with the ACh binding sites on nAChRs.  相似文献   

9.
The bioremediation of polluted groundwater and toxic waste sites requires that bacteria come into close physical contact with pollutants. This can be accomplished by chemotaxis. Five motile strains of bacteria that use five different pathways to degrade toluene were tested for their ability to detect and swim towards this pollutant. Three of the five strains (Pseudomonas putida F1, Ralstonia pickettii PKO1, and Burkholderia cepacia G4) were attracted to toluene. In each case, the response was dependent on induction by growth with toluene. Pseudomonas mendocina KR1 and P. putida PaW15 did not show a convincing response. The chemotactic responses of P. putida F1 to a variety of toxic aromatic hydrocarbons and chlorinated aliphatic compounds were examined. Compounds that are growth substrates for P. putida F1, including benzene and ethylbenzene, were chemoattractants. P. putida F1 was also attracted to trichloroethylene (TCE), which is not a growth substrate but is dechlorinated and detoxified by P. putida F1. Mutant strains of P. putida F1 that do not oxidize toluene were attracted to toluene, indicating that toluene itself and not a metabolite was the compound detected. The two-component response regulator pair TodS and TodT, which control expression of the toluene degradation genes in P. putida F1, were required for the response. This demonstration that soil bacteria can sense and swim towards the toxic compounds toluene, benzene, TCE, and related chemicals suggests that the introduction of chemotactic bacteria into selected polluted sites may accelerate bioremediation processes.  相似文献   

10.
Polyoxins D, E, and F which possess 5-carboxyuracil as the nucleobase were reacted selectively with sodium bisulfite at pH 4.0 resulting in facile decarboxylation to afford corresponding 5,6-dihydrouracil-6-sulfonates and uracil type polyoxins (polyoxins L, M, and K) in good yield. The former compounds were also converted to the latter almost quantitatively with mild alkali treatment. Biological activities of the transformed compounds were described.  相似文献   

11.
Intracellular recordings were made from identified neurons in the right parietal ganglion of the snail, Helix aspersa. Cells F 4, 5 and 6 were excited by 5-hydroxytryptamine (5-HT) and inhibited by dopamine while cells in the F 30 area were inhibited by both compounds. Low doses of both tryptamine and 6-HT produced weak excitation of cells F 4, 5 and 6 while higher doses of both compounds inhibit the activity of these cells. In terms of the inhibitory responses, tryptamine and 6-HT are approximately equipotent but between 10 and 100 times less potent than dopamine. d-Tubocurarine reversibly antagonized the excitatory action of 5-HT on cells F 4, 5 and 6 and converted tryptamine and 6-HT excitation to inhibition. In the presence of the antagonist, ergometrine, the dopamine inhibitory response was almost completely abolished while the inhibitory responses to tryptamine and 6-HT were converted to weak excitation. All four agonists inhibited cells in the F 30 area with the following potency ratios: dopamine much greater than tryptamine/6-HT greater than 5-HT. Tubocurarine had no antagonist effects on these responses while ergometrine reduced or blocked all four, often irreversibly. In potassium-free Ringer the inhibitory responses to all four agonists were enhanced. It is concluded that on cells F 4, 5 and 6, low concentrations of tryptamine and 6-HT act on 5-HT receptors while higher concentrations of both agonists act on dopamine receptors. On cells in the F 30 area, 5-HT, 6-HT and tryptamine all act on a dopamine receptor.  相似文献   

12.
13.
A new tripeptide, pre-sclerotiotide F (3), was isolated from a marine sediment-derived fungus, Aspergillus insulicola, along with five known compounds, one of which was new at the time of isolation, scerotiotide F (4). The absolute configuration elucidation of the new compound was determined using a combination of NMR, HR-ESI-MS, and optical rotation analyses. Cytotoxicities were measured in vitro against selected cancer cells. The effects of pre-sclerotiotide F (3) and sclerotiotide F (4) on LPS-induced NF-κB and iNOS expression were also measured.  相似文献   

14.
Dai SJ  Ma ZB  Wu Y  Chen RY  Yu DQ 《Phytochemistry》2004,65(23):3135-3141
Five Diels-Alder type adducts, named guangsangons F, G, H, I, and J, along with two known compounds, mulberrofuran J and kuwanon J, were isolated from Morus macroura Miq. Their structures were determined by means of spectroscopic analyses and chemical methods. These compounds were regarded biogenetically as Diels-Alder type adducts of dehydroprenylphenols and chalcone derivatives, and (1)H NMR variable temperature experiments suggested that they all existed as an equilibrium mixture of conformational isomers in solution. Among the isolated new compounds, guangsangons H, I, and J displayed potent antioxidant activities and moderate anti-inflammatory activities.  相似文献   

15.
Phenolic compounds were studied in the culms of five bamboo species collected in China: Yushania chungii, Fargesia robusta, Fargesia denudata, Fargesia rufa and Fargesia scabrida. All the species are eaten by giant panda (Ailuropoda melanoleuca). The culms contained phenolic acids and flavonoids in small concentrations, except for F. robusta, which did not contain flavonoids in detectable amounts. The species differed from each other in their phenolic composition. For example, F. rufa with the highest number of compounds clearly differed from other species. There were also differences among sampling sites, which reflect the differences among genotypes. Furthermore, there were clear ontogenetic differences in the culms: some compounds were present in mature culms but not in young (1–2 year old) culms, while the concentrations of other compounds decreased with increasing age. Over all, the composition and concentrations of soluble phenolic compounds in the bamboo culms were affected by species, age and site.  相似文献   

16.
As a type of intracellular nonreceptor tyrosine kinase, focal adhesion kinase (FAK) can be highly expressed in most types of tumours and is thus regarded as a promising antitumour target. In this study, a series of novel 2,4-diaminopyrimidine FAK-targeted inhibitors were designed, synthesized and characterized by 1H NMR, 13C HNMR, and HRMS spectra. These compounds, with an IC50 range of 5.0–205.1 nM, showed superior inhibitory activity against FAK. Two compounds, [18F]Q-2 and [18F]Q-4, with respective IC50 values of 5.0 nM and 21.6 nM, were labelled by 18F, accompanied by evaluation of their biodistributions. For [18F]Q-2, at 30 min post-injection, promising target-to-nontarget ratios were observed, associated with tumour/blood, tumour/muscle, and tumour/bone ratios of 1.17, 2.99 and 2.19, respectively. The results indicated that [18F]Q-2 is a potential PET tracer for tumour diagnosis.  相似文献   

17.
Human umbilical blood vessels have the ability to close spontaneously following delivery at term. It has been suggested that prostaglandins may have a possible physiological role in its closure. This study investigates the effects of 6 naturally occurring prostaglandins (A1, A2, B1, B2, E2, F2a) on the umbilical blood vessels. Umbilical cords were collected from cases of normal spontaneous vaginal deliveries and cesarian section at term. A total of 41 strips of umbilical arteries and 26 strips of umbilical veins from 24 cords were used. A 4-point bioassay method was used to compare the potency of prostaglandins A1, A2, B1 and F2a with PGE2. The effect of Polyphloretin Phosphate (PPP) on prostaglandin-induced contractions was studied on umbilical artery strips from 12 cords. The 6 prostaglandins exerted a stimulant effect on the isolated strips of human umbilical arteries. Prostaglandin B2 was the most potent compound on the umbilical vein, followed by PGA2. PPP in the concentration range of 10 to 40 mcg/ml completely eliminated the responses of PGE2, F2a, A1, A2, and B1. Responses to PGB2 were considerably but not completely abolished. PPP (up to 40 mcg/ml) did not affect contractions induced by 5-hydroxytryptamine, suggesting the presence of discrete receptor sites in the blood vessels for different pharmacologically active compounds. This is the first report of the constrictor effect of PGA and PGB compounds. These naturally occuring prostaglandins with high potencies (compared with other prostaglandins and other vasoactive substances) may play a role in spontaneous closure of umbilical vessels. PGE1, E2, F1 and F2a are found in umbilical blood vessels obtained at term.  相似文献   

18.
The bioremediation of polluted groundwater and toxic waste sites requires that bacteria come into close physical contact with pollutants. This can be accomplished by chemotaxis. Five motile strains of bacteria that use five different pathways to degrade toluene were tested for their ability to detect and swim towards this pollutant. Three of the five strains (Pseudomonas putida F1, Ralstonia pickettii PKO1, and Burkholderia cepacia G4) were attracted to toluene. In each case, the response was dependent on induction by growth with toluene. Pseudomonas mendocina KR1 and P. putida PaW15 did not show a convincing response. The chemotactic responses of P. putida F1 to a variety of toxic aromatic hydrocarbons and chlorinated aliphatic compounds were examined. Compounds that are growth substrates for P. putida F1, including benzene and ethylbenzene, were chemoattractants. P. putida F1 was also attracted to trichloroethylene (TCE), which is not a growth substrate but is dechlorinated and detoxified by P. putida F1. Mutant strains of P. putida F1 that do not oxidize toluene were attracted to toluene, indicating that toluene itself and not a metabolite was the compound detected. The two-component response regulator pair TodS and TodT, which control expression of the toluene degradation genes in P. putida F1, were required for the response. This demonstration that soil bacteria can sense and swim towards the toxic compounds toluene, benzene, TCE, and related chemicals suggests that the introduction of chemotactic bacteria into selected polluted sites may accelerate bioremediation processes.  相似文献   

19.
Fasciola gigantica is the causative organism of fascioliasis and is responsible for major economic losses in livestock production globally. F. gigantica thioredoxin1 (FgTrx1) is an important redox-active enzyme involved in maintaining the redox homeostasis in the cell. To identify a potential anti-fasciolid compound, we conducted a structure-based virtual screening of natural compounds from the ZINC database (n = 1,67,740) against the FgTrx1 structure. The ligands were docked against FgTrx1 and 309 ligands were found to have better docking score. These compounds were evaluated for Lipinski and ADMET prediction, and 30 compounds were found to fit well for re-docking studies. After refinement by molecular docking and drug-likeness analysis, three potential inhibitors (ZINC15970091, ZINC9312362, and ZINC9312661) were identified. These three ligands were further subjected to molecular dynamics simulation (MDS) to compare the dynamics and stability of the protein structure after binding of the ligands. The binding free energy analyses were calculated to determine the intermolecular interactions. The results suggested that the two compounds had a binding free energy of –82.237, and –109.52 kJ.mol?1 for compounds with IDs ZINC9312362 and ZINC9312661, respectively. These predicted compounds displayed considerable pharmacological and structural properties to be drug candidates. We concluded that these two compounds could be potential drug candidates to fight against F. gigantica parasites.  相似文献   

20.
5-HydroxyTriptamine 2A antagonists are potential targets for treatment of various cerebrovascular and cardiovascular disorders. In this study, we have developed and performed a unique screening pipeline for filtering ZINC database compounds on the basis of similarities to known antagonists to determine novel small molecule antagonists of 5-HydroxyTriptamine 2A. The screening pipeline is based on 2D similarity, 3D dissimilarity and a combination of 2D/3D similarity. The shortlisted compounds were docked to a 5-HydroxyTriptamine 2A homology-based model, and complexes with low binding energies (287 complexes) were selected for molecular dynamics (MD) simulations in a lipid bilayer. The MD simulations of the shortlisted compounds in complex with 5-HydroxyTriptamine 2A confirmed the stability of the complexes and revealed novel interaction insights. The receptor residues S239, N343, S242, S159, Y370 and D155 predominantly participate in hydrogen bonding. ππ stacking is observed in F339, F340, F234, W151 and W336, whereas hydrophobic interactions are observed amongst V156, F339, F234, V362, V366, F340, V235, I152 and W151. The known and potential antagonists shortlisted by us have similar overlapping molecular interaction patterns. The 287 potential 5-HydroxyTriptamine 2A antagonists may be experimentally verified.  相似文献   

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