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Didjour Albert Kambir Jean Brice Boti Thierry Acafou Yapi Zana Adama Ouattara Mathieu Paoli Ange Bighelli Flix Tomi Joseph Casanova 《化学与生物多样性》2020,17(1)
The chemical composition of 44 leaf oil samples of Laggera pterodonta (DC.) Sch.Bip. ex Oliv. (Asteraceae) from Côte d'Ivoire was investigated, using combination of chromatographic (GC‐FID) and spectroscopic (GC/MS, 13C‐NMR) techniques. Two oil samples chosen according to their chromatographic profiles were submitted to column chromatography and all fractions of CC were analyzed by GC‐FID, GC/MS and 13C‐NMR. In total, 83 components accounting for 96.5 to 99.4 % of the whole chemical composition were identified. Significant variations were observed within terpene classes: monoterpene hydrocarbons (0.4–22.7 %), oxygenated monoterpenes (32.9–54.9 %), sesquiterpene hydrocarbons (18.6–38.3 %) and oxygenated sesquiterpenes (3.5–38.4 %). Thus, the 44 compositions were subjected to hierarchical cluster analysis (HCA) and principal component analysis (PCA). Two groups were differentiated according to their composition. All the samples contained 2,5‐dimethoxy‐p‐cymene, α‐humulene and (E)‐β‐caryophyllene among the main components. Other components were present at appreciable contents and allowed differentiation of two groups: sabinene and germacrene D for Group I; 10‐epi‐γ‐eudesmol and eudesm‐7(11)‐en‐4α‐ol for Group II. All the samples collected in Eastern Côte d'Ivoire constituted Group I, while samples collected in the Central area of the country constituted Group II. 相似文献
2.
Justine D. Ceusters Ange A. Mouithys-Mickalad Thierry J. Franck Sandrine Derochette Alain Vanderplasschen Ginette P. Deby-Dupont Didier A. Serteyn 《Mitochondrion》2013,13(5):410-416
Horses are particularly sensitive to excessive inflammatory reaction where myeloperoxidase, a marker of inflammation, may contribute to mitochondrial dysfunctions. This study investigated the interaction between myeloperoxidase and cultured primary equine skeletal myoblasts, particularly its effect on mitochondrial respiration combined or not with anoxia followed by reoxygenation (AR). We showed that active myeloperoxidase entered into the cells, interacted with mitochondria and decreased routine and maximal respirations. When combined with AR, myeloperoxidase caused a further decrease of these respiratory parameters while the leak increased. Our results indicate that myeloperoxidase amplifies the mitochondrial damages initiated by AR phenomenon and alters the mitochondrial function. 相似文献
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Composition and Chemical Variability of the Needle Oil from Pinus halepensis growing in Corsica
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The composition of oil samples isolated from needles of Pinus halepensis growing in three locations in Corsica (Saleccia, Capo di Feno, and Tre Padule) has been investigated by combination of chromatographic (GC with retention indices) and spectroscopic (MS and 13C‐NMR) techniques. In total, 35 compounds that accounted for 77 – 100% of the whole composition have been identified. α‐Pinene, myrcene, and (E)‐β‐caryophyllene were the major component followed by α‐humulene and 2‐phenylethyl isovalerate. Various diterpenes have been identified as minor components. 47 Oil samples isolated from pine needles have been analyzed and were differentiated in two groups. Oil samples of the first group (15 samples) contained myrcene (M = 28.1 g/100 g; SD = 10.6) and (E)‐β‐caryophyllene (M = 19.0 g/100 g; SD = 2.2) as major components and diterpenes were absent. All these oil samples were isolated from pine needles harvested in Saleccia. Oil samples of the second group (32 samples) contained mostly (E)‐β‐caryophyllene (M = 28.7 g/100 g; SD = 7.9), α‐pinene (M = 12.3 g/100 g; SD = 3.6), and myrcene (M = 11.7 g/100 g; SD = 7.3). All these oil samples were isolated from pine needles harvested in Capo di Feno and Tre Padule. 相似文献
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Twenty‐three resin samples have been obtained by tapping from individual Pinus pinaster adult trees grown in Corsica and submitted to acido‐basic partition. Identification and quantitative determination of resin acids has been carried out using 13C‐NMR spectroscopy following a method developed by our group. The main components were dehydroabietic acid (up to 37.6 %), levopimaric acid (up to 35.5 %) and abietic acid (up to 24.7 %). A lignan, pinoresinol, has been identified in some samples. Within the 23 compositions, submitted to k‐means analysis and Principal Component Analysis, two clusters have been perfectly differentiated, whose compositions were dominated by dehydroabietic acid (Group I, M=23.5 %, SD=6.3) and levopimaric acid (Group II, M=21.2 %; SD=6.2), respectively. Both compositions have been observed in the three locations of harvest. 相似文献
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Mouithys-Mickalad Mareque A Faez JM Chistiaens L Kohnen S Deby C Hoebeke M Lamy M Deby-Dupont G 《Redox report : communications in free radical research》2004,9(2):81-87
Four analogues of Ebselen were synthesized and their glutathione peroxidase activity and antioxidant property evaluated and compared to Ebselen. Among the studied compounds, only diselenide [3] exhibited both glutathione peroxidase activity and radical-scavenging capability. Compounds [3] and [4] showed a strong inhibitory effect (53% and 43%, respectively) on the lipid peroxidation of linoleic acid compared to Ebselen and selenide derivatives ([1] and [2]) which were less active (28%, 26% and 18% inhibition, respectively). A concentration-dependent inhibitory effect was also found in the model of the formation of ABTS*+ radical cation: 65% and 89% inhibition for compound [3] at 10(-4) M and 5 x 10(-5) M, respectively, and 68% and 90% for compound [4], compared to 14% and 52% inhibition for Ebselen and the diselenides [1] and [2] (29%, 46% and 45%, 68%, respectively). By EPR spin trapping technique, the following inhibitory profile of the Ebselen analogues was observed towards the formation of thiyl radicals: Ebselen = [3]>[1]>[2]>[4]. Studies with compound [3] are in progress on oxidative stress cell models. 相似文献
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Ricardo H. Flores Jiménez Marie‐Ange Do Cao Miyeon Kim David S. Cafiso 《Protein science : a publication of the Protein Society》2010,19(2):269-278
Site‐directed spin labeling (SDSL) was used to investigate local structure and conformational exchange in two bacterial outer‐membrane TonB‐dependent transporters, BtuB and FecA. Protecting osmolytes, such as polyethylene glycols (PEGs) are known to modulate a substrate‐dependent conformational equilibrium in the energy coupling motif (Ton box) of BtuB. Here, we demonstrate that a segment that is N‐terminal to the Ton box in BtuB, is in conformational exchange between ordered and disordered states with or without substrate. Protecting osmolytes shift this equilibrium to favor the more ordered, folded state. However, a segment of BtuB that is C‐terminal to the Ton box that is not solvent exposed is insensitive to PEGs. Protecting osmolytes also modulate a conformational equilibrium in the Ton box of FecA, with larger molecular weight PEGs producing the largest shifts in the conformational free energy. These data indicate that solvent‐exposed regions of these transporters undergo conformational exchange and that regions of these transporters that are involved in protein–protein interactions sample multiple conformational substates. The sensitivity to solute provides an explanation for differences seen between two high‐resolution structures of BtuB, which each likely represent one conformation from a subset of states that are normally sampled by the protein. This work also illustrates how SDSL and osmolytes may be used to characterize and quantitate conformational equilibria in membrane proteins. 相似文献
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A. Grammenos A. Mouithys-Mickalad M. Lismont M. Hoebeke 《Biochemical and biophysical research communications》2010,398(3):350-8062
A new way to study the action of cyclodextrin was developed to quantify the damage caused on cell membrane and lipid bilayer. The Electron Spin Resonance (ESR) spectroscopy was used to study the action of Randomly methylated-beta-cyclodextrin (Rameb) on living cells (HCT-116). The relative anisotropy observed in ESR spectrum of nitroxide spin probe (5-DSA and cholestane) is directly related to the rotational mobility of the probe, which can be further correlated with the microviscosity. The use of ESR probes clearly shows a close correlation between cholesterol contained in cells and cellular membrane microviscosity. This study also demonstrates the Rameb ability to extract cholesterol and phospholipids in time- and dose-dependent ways. In addition, ESR spectra enabled to establish that cholesterol is extracted from lipid rafts to form stable aggregates. The present work supports that ESR is an easy, reproducible and noninvasive technique to study the effect of cyclodextrins on cell membranes. 相似文献
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Marcano M Pugh T Cros E Morales S Portillo Páez EA Courtois B Glaszmann JC Engels JM Phillips W Astorga C Risterucci AM Fouet O González V Rosenberg K Vallat I Dagert M Lanaud C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,114(5):877-884
A sound understanding of crop history can provide the basis for deriving novel genetic information through admixture mapping.
We confirmed this, by using characterization data from an international collection of cocoa, collected 25 years ago, and from
a contemporary plantation. We focus on the trees derived from three centuries of admixture between Meso-American Criollo and
South American Forastero genomes. In both cacao sets of individuals, linkage disequilibrium extended over long genetic distances
along chromosome regions, as expected in populations derived from recent admixture. Based on loose genome scans, genomic regions
involved in useful traits were identified. Fifteen genomic regions involved in seed and fruit weight variation were highlighted.
They correspond to ten previously identified QTLs and five novel ones. Admixture mapping can help to add value to genetic
resources and thus, help to encourage investment in their conservation.
Maria Marcano and Tatiana Pugh contributed equally to this work. 相似文献
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The work reported herein deals with the synthesis and the aggregation behavior studies of synthetic lipids bearing a non-ionic polar head made up of a tris(hydroxymethyl) aminomethane (tris) moiety linked with an aminoglycerol interface. The hydrophobic chains with variable lengths were grafted onto the hydroxyl functions of the aminoglycerol residue through ester or carbamate bonds. Tiny chemical modifications within this family of non-ionic surfactants brought about major variations in their aggregation behavior. They formed vesicles, tubules, and also small stable end-capped tubules - called vesicular nanotubes -, when the polar head bore two heptadecyl chains linked through a carbamate bond. Various techniques (nanosizer measurements, freeze fracture electron microscopy (FFEM), transmission electron microscopy (TEM), carboxyfluorescein (CF)) encapsulation were used to specify the structure of these assemblies. Notably, the vesicular nanotubes exhibited a small size, a fair polydispersity, great stability in an aqueous solution (up to 1 year) and a good efficiency to entrap and slowly release a probe such as carboxyfluoresceine: all these properties are perfectly suitable for their use as potential drug carriers. 相似文献