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71.
The plant polyphenol trans-resveratrol (3, 5, 4'-trihydroxystilbene) mainly found in grape, peanut and other few plants, displays a wide range of biological effects. Numerous in vitro studies have described various biological effects of resveratrol. In order to provide more information regarding absorption, metabolism, and bioavailability of resveratrol, various research approaches have been performed, including in vitro, ex vivo, and in vivo models. In recent years, the induction of resveratrol synthesis in plants which normally do not accumulate such polyphenol, has been successfully achieved by molecular engineering. In this context, the ectopic production of resveratrol has been reported to have positive effects both on plant resistance to biotic stress and the enhancement of the nutritional value of several widely consumed fruits and vegetables. The metabolic engineering of plants offers the opportunity to change the content of specific phytonutrients in plant - derived foods. This review focuses on the latest findings regarding on resveratrol bioproduction and its effects on the prevention of the major pathological conditions in man.  相似文献   
72.
A new pentasubstituted oxiranyldecene, named viridenepoxydiol, has been isolated (0.9 mg/L) from the culture filtrate of a strain of Trichoderma viride showing in vitro and in vivo antagonistic activity against Sclerotium rolfsii, which is the causal agent of crown and stem rot of artichoke. Viridenepoxydiol was characterized as 3,5,9-trimethyl-2-oxiranyl-dec-8-ene-2,5-diol (3) using spectroscopic methods. It showed inhibitor effect on mycelial growth of S. rolfsii and its minimum inhibitory concentration (over 90% inhibition) was found to be 396 mug/mL. This is the first time that viridenepoxydiol was reported.  相似文献   
73.
This paper describes a method for achieving qualitative identification of four rice varieties from two different Italian regions. To estimate the presence of genetic diversity among the four rice varieties, we used polymerase chain reaction-randomly amplified polymorphic DNA (PCR-RAPD) markers, and to elucidate whether a relationship exists between the ground and the specific characteristics of the product, we studied proximate composition, fatty acid composition, mineral content, and total antioxidant capacity. Using principal component analysis on genomic and compositional data, we were able to classify rice samples according to their variety and their district of production. This work also examined the discrimination ability of different parameters. It was found that genomic data give the best discrimination based on varieties, indicating that RAPD assays could be useful in discriminating among closely related species, while compositional analyses do not depend on the genetic characters only but are related to the production area.  相似文献   
74.
Wheat quality criteria continually evolve in response to market pressure and consumer preference. Characterization of cereal cultivars for quality and agronomic properties, have widely shown the importance of the protein content to ensure good quality products. The aim of this work is a comparison of reversed-phase high performance liquid chromatography (RP-HPLC) and free zone capillary electrophoresis (FZCE) in the identification of Italian wheat cultivars and detection of durum wheat flour adulteration. Mainly alcohol soluble (gliadins) and water soluble (albumins) proteins were extracted from 14 common wheat cultivars and from 9 durum wheat cultivars. In RP-HPLC chromatograms, wheat albumins and gliadins eluted between 3 and 9 min and between 10 and 42 min, respectively. Even if the chosen chromatographic conditions (reversed phase) did not permit a complete resolution of hydrophilic proteins such as albumins, a good reproducibility was observed for both albumins and gliadins. In FZCE electropherograms, wheat albumins and gliadins migrated between 8 and 14 min and 16-25 min, respectively. A good reproducibility was found for wheat albumins, while the relatively poor reproducibility of gliadin fractions was a consequence of the selected separation conditions aimed to separate in the same run either hydrophilic (albumins) and alcohol-soluble (gliadins) proteins. The principal component analysis (PCA) of HPLC and FZCE data evidenced that both techniques allowed the univocal identification of the great proportion of investigated wheat cultivars. Three peaks were exclusively detected in RP-HPLC chromatograms of common wheat cultivars, while three unique peaks were found in FZCE electropherograms of common wheat cultivars. These peaks were investigated as a basis for detecting and estimating the adulteration of durum wheat flour with flour from common wheat. The direct relationship between the area of the peaks and adulteration level enabled standard curves to be constructed. The standard curves showed that adulteration may be quantified by either RP-HPLC or FZCE.  相似文献   
75.
The flavonoid composition of three phenotypes of "Zolfino" landraces, a typical bean grown in Tuscany, has been elucidated by means of HPLC-DAD and HPLC-MS analysis. Flavonols, isoflavones, and anthocyanins have been separated and determined in the different samples chosen on the basis of their seed coat color. A flavonol that has not been previously found in Phaseolus vulgaris L. seeds has been characterized. The quantitative data show the presence of flavonols (ranging from 709 to 118 mg/kg of fresh weight), isoflavones (ranging from 14 to 2 mg/kg of fresh weight), and anthocyanins, in black beans only. These results show that this genotype could be very interesting from a nutritional point of view.  相似文献   
76.
A new antifungal 6-substituted 2H-pyran-2-one, named viridepyronone, has been isolated from a cultural filtrate of a strain of Trichoderma viride showing antagonistic activity in vitro toward Sclerotium rolfsii, which is the causal agent of crown and stem rot of artichoke. Viridepyronone was characterized as 6-(4-oxopentyl)-2H-pyran-2-one 2 with spectroscopic methods. Bioassays showed that viridepyronone had a good antifungal activity against S. rolfsii, and its minimum inhibitory concentration (over 90% inhibition) was found to be 196 microg/mL. This is the first report of viridepyronone produced by any species of fungi.  相似文献   
77.
BACKGROUND: Quinoxyfen is a fungicide of the phenoxyquinoline class used to control powdery mildew, Uncinula necator (Schw.) Burr. Owing to its high persistence and strong sorption in soil, it could represent a risk for soil organisms if they are exposed at ecologically relevant concentrations. The objective of this paper is to predict the bioconcentration factors (BCFs) of quinoxyfen in earthworms, selected as a representative soil organism, and to assess the uncertainty in the estimation of this parameter. Three fields in each of four vineyards in southern and northern Italy were sampled over two successive years. RESULTS: The measured BCFs varied over time, possibly owing to seasonal changes and the consequent changes in behaviour and ecology of earthworms. Quinoxyfen did not accumulate in soil, as the mean soil concentrations at the end of the 2 year monitoring period ranged from 9.16 to 16.0 µg kg?1 dw for the Verona province and from 23.9 to 37.5 µg kg?1 dw for the Taranto province, with up to eight applications per season. To assess the uncertainty of the BCF in earthworms, a probabilistic approach was used, firstly by building with weighted bootstrapping techniques a generic probabilistic density function (PDF) accounting for variability and incompleteness of knowledge. The generic PDF was then used to derive prior distribution functions, which, by application of Bayes' theorem, were updated with the new measurements and a posterior distribution was finally created. CONCLUSION: The study is a good example of probabilistic risk assessment. The means of mean and SD posterior estimates of log BCFworm (2.06, 0.91) are the ‘best estimate values’. Further risk assessment of quinoxyfen and other phenoxyquinoline fungicides and realistic representative scenarios for modelling exercises required for future authorization and post‐authorization requirements can now use this value as input. Copyright © 2011 Society of Chemical Industry  相似文献   
78.
79.
Eltenac (ELT) [4-(2,6-dichlorophenyl)amino-3-thiophene] is a non-steroidal anti-inflammatory drug (NSAID) that was developed for veterinary use in horses and cattle. The pharmacokinetics of ELT was evaluated in horses at 0.5 mg/kg body weight (BW) after single IV injection after 5 days of repeated IV administration and after a single IV injection in horses previously subjected to 250 mg/kg BW of sodium bicarbonate (NaHCO3) as an alkalization treatment. The aim was to determine whether blood and subsequent urinary alkalization could modify the pharmacokinetics of ELT. Drug quantification was performed with serum and urine using high performance liquid chromatography with UV-visible detection. The results were also integrated with cyclo-oxygenase-inhibition literature data to review the dosage scheme of ELT in horses. After a single intravenous administration, ELT was characterized by rapid distribution (mean t½λ1 = 0.18 ± 0.07 hour) and a short elimination half-life (mean t½λ2 = 2.9 ± 0.68 hour). The volume of distribution was small (Vdss = 253.51 ± 47.55 mL/kg), which is likely because of the high percentage of drug protein binding (approximately 97%). The AUC0-∞ and ClB were 6.92 ± 0.84 h*μg/mL and 73.2 ± 10 mL/h/kg, respectively. Repeated administration did not cause either accumulation or modification of the pharmacokinetic profile. The in vitro effective concentrations were maintained for a 6-hour period. The alkalization procedure appeared to accelerate drug elimination, as ELT was quantifiable only for 6 hours; however, the drug clearance was not significantly modified. Thus, the administration of alkaline compounds to accelerate the elimination of ELT is not completely confirmed.  相似文献   
80.
Secondary metabolites contained in marine organisms disclose diverse pharmacological activities, due to their intrinsic ability to recognize bio-macromolecules, which alter their expression and modulate their function. Thus, the identification of the cellular pathways affected by marine natural products is crucial to provide important functional information concerning their mechanism of action at the molecular level. Perthamide C, a marine sponge metabolite isolated from the polar extracts of Theonella swinhoei and endowed with a broad and interesting anti-inflammatory profile, was found in a previous study to specifically interact with heat shock protein-90 and glucose regulated protein-94, also disclosing the ability to reduce cisplatin-mediated apoptosis. In this paper, we evaluated the effect of this compound on the whole proteome of murine macrophages cells by two-dimensional DIGE proteomics. Thirty-three spots were found to be altered in expression by at least 1.6-fold and 29 proteins were identified by LC ESI-Q/TOF-MS. These proteins are involved in different processes, such as metabolism, structural stability, protein folding assistance and gene expression. Among them, perthamide C modulates the expression of several chaperones implicated in the folding of proteins correlated to apoptosis, such as Hsp90 and T-complexes, and in this context our data shed more light on the cellular effects and pathways altered by this marine cyclo-peptide.  相似文献   
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