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11.
Romain Gastineau Fran?ois Turcotte Jean-Bernard Pouvreau Michèle Moran?ais Jo?l Fleurence Eko Windarto Fiddy Semba Prasetiya Sulastri Arsad Pascal Jaouen Mathieu Babin Laurence Coiffard Céline Couteau Jean-Fran?ois Bardeau Boris Jacquette Vincent Leignel Yann Hardivillier Isabelle Marcotte Nathalie Bourgougnon Réjean Tremblay Jean-Sébastien Deschênes Hope Badawy Pamela Pasetto Nikolai Davidovich Gert Hansen Jens Dittmer Jean-Luc Mouget 《Marine drugs》2014,12(6):3161-3189
In diatoms, the main photosynthetic pigments are chlorophylls a and c, fucoxanthin, diadinoxanthin and diatoxanthin. The marine pennate diatom Haslea ostrearia has long been known for producing, in addition to these generic pigments, a water-soluble blue pigment, marennine. This pigment, responsible for the greening of oysters in western France, presents different biological activities: allelopathic, antioxidant, antibacterial, antiviral, and growth-inhibiting. A method to extract and purify marennine has been developed, but its chemical structure could hitherto not be resolved. For decades, H. ostrearia was the only organism known to produce marennine, and can be found worldwide. Our knowledge about H. ostrearia-like diatom biodiversity has recently been extended with the discovery of several new species of blue diatoms, the recently described H. karadagensis, H. silbo sp. inedit. and H. provincialis sp. inedit. These blue diatoms produce different marennine-like pigments, which belong to the same chemical family and present similar biological activities. Aside from being a potential source of natural blue pigments, H. ostrearia-like diatoms thus present a commercial potential for aquaculture, cosmetics, food and health industries. 相似文献
12.
Summary Flowering plants of Rosa hybrida L. cv Meirutral have been obtained either from direct regeneration of adventitious shoots on leaf and root fragments, or through organogenesis and somatic embryogenesis on calli derived from anther, ovule, petal, sepal, receptacle, leaf, stem internode, root and zygotic embryo tissues. The calli derived from floral parts exhibited rhizogenesis. In this case direct induction of adventitious shoots from selected roots had to be performed in order to generate plants. A histological study of the morphogenetic calli was carried out. The plants regenerated directly and those regenerated from calli of leaf, stem internode, root and zygotic embryo tissues, together with reference plants propagated by cuttings, were compared on a phenotypic basis by taking into account petal number, form and colour, and plant growth habit. From these observations, it can be concluded that directly regenerated plants are as stable as reference plants while plants regenerated from callus are unstable, especially those derived from zygotic embryo tissues.Abbreviations BAP
6-benzylaminopurine
- 2,4-D
2,4-Dichlorophenoxyacetic acid
- GA3
gibberellic acid
- IAA
3-indole-acetic acid
- MS
Murashige and Skoog
- NAA
1-naphthalene acetic acid 相似文献
13.
The absence of reliable estimates of distributions of antioxidants in food emulsions hinders the development of a useful method for comparing the efficiencies of antioxidants. Here we describe the application of a pseudophase kinetic model, originally developed for homogeneous microemulsions, to the determination of distribution constants of tert-butylhydroquinone, TBHQ, in a fluid, opaque, model food emulsion composed of the nonionic emulsifier C(12)E(6), octane, and water. This kinetic method should be applicable to a wide variety of charged and uncharged antioxidants in emulsions composed of charged and uncharged emulsifiers. The distribution constants for partitioning of TBHQ between the oil and surfactant film regions, K(O)(I), and the aqueous and surfactant film regions, K(W)(I), were obtained by fitting changes in first-order rate constants, k(obs), with emulsifier volume fraction for the reaction of 4-hexadecyl-2,6-dimethylbenzenediazonium ion, 16-ArN(2)(+), with TBHQ. The rate of formation of the reduced arene product hexadecyl-2,6-dimethylbenzene, 16-ArH, was followed by HPLC. About 90% of the TBHQ is in the surfactant film at about 2% volume fraction of C(12)E(6), which suggests that this region may be the primary site of antioxidant activity for neutral phenolic antioxidants. 相似文献
14.
Enzymatic synthesis of aroma compound xylosides using transfer reaction by Trichoderma longibrachiatum xylanase 总被引:1,自引:0,他引:1
Kadi N Belloy L Chalier P Crouzet JC 《Journal of agricultural and food chemistry》2002,50(20):5552-5557
Enzymatic synthesis of aroma compound xylosides was performed by Trichoderma longibrachiatum xylanase. Information concerning the nature of xylosides present in the reaction medium was obtained by GC-EI-MS, by GC-NCI-MS of TFA derivatives, and by positive FAB-MS of the reaction mixtures. Moreover, the structures of isolated benzyl beta-D-xylopyranoside and 4-O-beta-xylopyranosyl-beta-D-xylopyranoside were established by (1)H and (13)C NMR and heteronuclear two-dimensional ((1)H-(13)C) chemical shift correlation. The results obtained for hexyl and benzyl alcohol xylosides indicated that a reaction implying a transfer of one to two or three xylose units from xylan was involved. The enzyme was able to recognize xylobiose, xylotriose, and xylan as xylose donors. Benzyl xyloside, produced independently of xylobioside and xylotrioside, was found as the major kinetic product of the reaction. Benzyl xyloside was produced in higher quantities and at a higher rate than that obtained for the di- and trixyloside derivatives. The maximum production for benzyl xyloside, 1.29 g/L, was obtained in the presence of hexane (50%) used as cosolvent. Xylosides and xylobiosides of several aroma compounds, (Z)-hex-3-en-1-ol, heptan-2-ol, geraniol, nerol, and citronellol, were synthesized in different amounts, from 850 mg/L for (Z)-hex-3-en-1-yl xylosides to 1.5 mg/L for citronellyl xylosides. No synthesis occurred when menthol, linalool, and eugenol were used as acceptors. 相似文献
15.
Mrklas Ole Chu Angus Lunn Stuart Bentley Laurence R. 《Water, air, and soil pollution》2004,159(1):249-263
The release of alkanolamines and glycols into the subsurface soils poses a potential hazard to the environment through impacted soil and groundwater. This study investigated aerobic and anaerobic biodegradability of monoethanolamine (MEA), ethylene glycol (MEG) and triethylene glycol (TEG). Significant levels of MEA (31 000 mg/kg), MEG (500 mg/kg) and TEG (2100 mg/kg) were successfully aerobically biodegraded in bioreactors. The aerobic slurry experiments suggested initial phosphate (P) limitation, as biodegradation rates increased by one order of magnitude after phosphate addition. Anaerobic decay of MEA, MEG and TEG was unaffected by P-addition. MEA, MEG and TEG degradation products such as acetate, ethanol and ammonium at about 75 000 mg/kg, 8100 mg/kg and 8800 mg/kg degraded completely and did not prevent aerobic biodegradation. This study confirms proposed biodegradation pathways of MEA, MEG, TEG and their breakdown products in natural soil and groundwater using indigenous microbes. Levels of contamination studied here are significantly higher than previously reported. 相似文献
16.
Coiled-coil proteins of the golgin family have been implicated in intra-Golgi transport through tethering coat protein complex I (COPI) vesicles. The p115-golgin tether is the best studied, and here we characterize the golgin-84-CASP tether. The vesicles bound by this tether were strikingly different from those bound by the p115-golgin tether in that they lacked members of the p24 family of putative cargo receptors and contained enzymes instead of anterograde cargo. Microinjected golgin-84 or CASP also inhibited Golgi-enzyme transport to the endoplasmic reticulum, further implicating this tether in retrograde transport. These and other golgins may modulate the flow patterns within the Golgi stack. 相似文献
17.
Hypnotically created memory among highly hypnotizable subjects 总被引:2,自引:0,他引:2
A pseudomemory of having been awakened by some loud noises during a night of the previous week was suggested to 27 highly hypnotizable subjects during hypnosis. Posthypnotically, 13 of them stated that the suggested event had actually occurred. This finding has implications for the investigative use of hypnosis in a legal context. 相似文献
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Marimuthu MP Jolivet S Ravi M Pereira L Davda JN Cromer L Wang L Nogué F Chan SW Siddiqi I Mercier R 《Science (New York, N.Y.)》2011,331(6019):876
Cloning through seeds has potential revolutionary applications in agriculture, because it would allow vigorous hybrids to be propagated indefinitely. However, asexual seed formation or apomixis, avoiding meiosis and fertilization, is not found in the major food crops. To develop de novo synthesis of apomixis, we crossed Arabidopsis MiMe and dyad mutants that produce diploid clonal gametes to a strain whose chromosomes are engineered to be eliminated after fertilization. Up to 34% of the progeny were clones of their parent, demonstrating the conversion of clonal female or male gametes into seeds. We also show that first-generation cloned plants can be cloned again. Clonal reproduction through seeds can therefore be achieved in a sexual plant by manipulating two to four conserved genes. 相似文献