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71.
Assunta Esposito Pietro Filippo De Luca Vittoria Graziani Brigida DAbrosca Antonio Fiorentino Monica Scognamiglio 《Molecules (Basel, Switzerland)》2021,26(13)
Olea europaea germplasm is constituted by a huge number of cultivars, each one characterized by specific features. In this context, endemic cultivars evolved for a very long period in a precise local area, developing very specific traits. These characteristics include the production and accumulation of phytochemicals, many of which are also responsible for the nutraceutical value of the drupes and of the oils therefrom. With the aim of obtaining information on the phytochemical profile of drupes of autochthonous cultivars of Cilento, Vallo di Diano and Alburni National Park, a metabolomics-based study was carried out on 19 selected cultivars. Multivariate data analysis of 1H-NMR data and 2D NMR analyses allowed the rapid identification of metabolites that were qualitatively and/or quantitatively varying among the cultivars. This study allowed to identify the cultivars Racioppella, Guglia, Pizzulella, Oliva amara, and Racioppa as the richest in health-promoting phenolic compounds. Furthermore, it showed a significant variability among the different cultivars, suggesting the possibility of using metabolic fingerprinting approaches for cultivar differentiation, once that further studies aimed at assessing the influence of growing conditions and environmental factors on the chemical profiles of single cultivars are carried out. 相似文献
72.
Abstract The IR spectra of the linkage isomers [Pd(bipy)(SCN)2] and [Pd(bipy)(NCS)2] have been determined in the C≡N stretching region (2200–2000 cm?1) and below 500 cm?1. The band shifts resulting from deuteration of the 2,2′-bipyridine (bipy) ring and 15NCS-labelling are shown to provide a ready means for distinguishing between the internal ligand modes, the μPd-N(bipy) and μPd-SCN/μPd-NCS vibrations. The assignment technique has been further extended to the complexes [Pt(bipy)(SCN)2] and [Pd(phen)(SCN)2] (phen = 1,10-phenanthroline). Finally, a comparison between the IR spectra of [Pd(bipy)(NCO)2], [Pd(bipy)(NCS)2] and [Pd(bipy)(SCN)2] reveals that the frequencies μM-NCO, μM-NCS and μM-SCN decrease in the sequence NCO > NCS > SCN. 相似文献
73.
Four new phenolic dimers and trimers that contain ferulic acid moieties were isolated from the alkaline hydrolyzate of insoluble maize bran fiber and their structures were established by 1D/2D NMR and mass spectrometry. The biological role of one dimer remains unclear whereas the dimeric vanillin-ferulic acid-cross-product probably represents an oxidative degradation product from the corresponding diferulate. Both ferulic acid dehydrotrimers are able to cross-link polysaccharide chains. However, the 5-5/8-O-4(H2O)-triferulic acid may be a cross-link in its identified structure whereas we assume that the identified 8-O-4/8-5(non-cyclic)-triferulic acid arose from a natural 8-O-4/8-5(cyclic)-triferulate analog during the saponification process. 相似文献
74.
Jaime Rodríguez André Ferraz Raquel F. P. Nogueira Irene Ferrer Elisa Esposito Nelson Durán 《Applied biochemistry and biotechnology》1997,62(2-3):233-242
The lignin biodegradation process has an important role in the carbon cycle of the biosphere. The study of this natural process
has developed mainly with the use of basidiomycetes in laboratory investigations. This has been a logical approach since most
of the microorganisms involved in lignocellulosic degradation belong to this class of fungi. However, other microorganisms
such as ascomycetes and also some bacteria, are involved in the lignin decaying process. This work focuses on lignin biodegradation
by a microorganism belonging to the ascomycete class,Chrysonilia sitophila. Lignin peroxidase production and characterization, mechanisms of lignin degradation (lignin model compounds and lignin in
wood matrix) and biosynthesis of veratryl alcohol are outstanding. Applications of C.sitophila for effluent treatment, wood biodegradation and single-cell protein production are also discussed. 相似文献
75.
Seven diterpenoids, isolated due to their ability to inhibit spore germination in the plant pathogenic fungus Magnaporthe grisea, were obtained from cultures of the basidiomycete Coprinus heptemerus. The structures of the compounds, named heptemerones A-G, were determined with spectroscopic techniques. 相似文献
76.
We consider the flow of a gas in a channel whose walls are kept at fixed (different) temperatures. There is a constant external force parallel to the boundaries which may themselves also be moving. The system is described by the stationary Boltzmann equation to which are added Maxwellian boundary conditions with unit accommodation coefficient. We prove that when the temperature gap, the relative velocity of the planes, and the force are all sufficiently small, there is a solution which converges, in the hydrodynamic limit, to a local Maxwellian with parameters given by the stationary solution of the corresponding compressible Navier-Stokes equations with no-slip voundary conditions. Corrections to this Maxwellian are obtained in powers of the Knudsen number with a controlled remainder. 相似文献
77.
Summary In an important experiment performed on a SQUID system, Rouse, Han and Lukens report the first observation of resonant tunnelling
between macroscopically distinct quantum levels. We support the experiment with the first theoretical approach for the phenomenon. 相似文献
78.
79.
During adiabatic deformation experiments on polyisobutylene of various molecular weights and on polyvinylacetate, the temperature change was measured. The thermal effects occurring during the subsequent stress relaxation were also recorded. From all data, the conclusion was drawn that the entropic elasticity theory is obeyed for temperatures sufficiently above the glass transition temperature. When the value of Tg is approached, some interesting energy effects become appreciable. 相似文献
80.
Summary We study the effect of temperature on the lifetime of the resonant macroscopic quantum tunnelling voltage state. In view of
experiments we consider a merit factor in order to balance between measuring extremely small signals of longer duration or
larger signals of shorter duration. 相似文献