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331.
A new route for the synthesis of fatty alcohol derivatives of hydroxytyrosol and other olive oil phenolic compounds was developed to allow the preparation of unsaturated derivatives. The biological activity of synthesized compounds was evaluated. Most of the compounds presented a significant antioxidant activity on low-density lipoprotein (LDL) particles. The activity of the tested products was significantly influenced by the number and position of unsaturations as well as modifications on the polar head of the synthesized compounds. Some of them presented modulation of food intake in rats and, due to their molecular similarity with CB(1) endogenous ligands, the endocannabinoid system and PPAR-α were also evaluated as potential targets. The pharmacodynamics could not be totally explained by CB(1) and PPAR-α receptor interactions because only two of the four compounds with biological activity showed a CB(1) activity and all of them presented low PPAR-α affinity, not justifying its whole in vivo activity. The hydroxytyrosol linoleylether (7) increased LDL resistance to oxidation with a capacity similar to that of hydroxytyrosol and was the most active in vivo compound with a hypophagic effect comparable to that of oleoylethanolamine. We consider that this compound could be a good lead compound for future drug development in obesity treatments.  相似文献   
332.
333.
OBJECTIVE: Alcohol consumption may play a role in the development of obesity but the relationship between alcohol and weight is still unclear. The aim of our study was to assess the cross-sectional association of intakes of total alcohol and of specific alcoholic beverages (wine, beer and spirits) with waist-to-hip ratio (WHR) and body mass index (BMI) in a large sample of adults from all over France. DESIGN: Cross-sectional. SETTING: Participants were free-living healthy volunteers of the SU.VI.MAX study (an intervention study on the effects of antioxidant supplementation on chronic diseases). SUBJECTS: For 1481 women aged 35-60 years and 1210 men aged 45-60 years, intakes of total alcohol and specific alcoholic beverages were assessed by six 24-hour dietary records. BMI and WHR were measured during a clinical examination the year after. RESULTS: A J-shaped relationship was found between total alcohol consumption and WHR in both sexes and between total alcohol consumption and BMI in men only (P<0.05). The same relationships were observed with wine (P<0.05); men and women consuming less than 100 g day(-1) had a lower BMI (men only) and WHR than non-drinkers or those consuming more. Spirits consumption was positively associated with BMI (linear regression coefficient beta=0.21, 95% confidence interval (CI): 0.09-0.34 and beta=0.22, 95% CI: 0.06-0.39 for men and women, respectively) and WHR (beta=0.003, 95% CI: 0.001-0.005 and beta=0.003, 95%CI: 0.0002-0.006) in both sexes in a linear fashion. No relationship between beer consumption and BMI or WHR was found. CONCLUSION: If confirmed in longitudinal studies, our results indicate that consumption of alcoholic beverages may be a risk factor for obesity.  相似文献   
334.
Grape antioxidant dietary fiber (GADF) is a phenolic-rich dietary fiber matrix. The aim of this work was to determine which phenolic compounds come into contact with colonic epithelial tissue after the ingestion of GADF. By use of HPLC-ESI-MS/MS techniques phenolic metabolites were detected in feces, cecal content, and colonic tissue from rats. Free (epi)catechin (EC) was detected in all three sources, and more than 20 conjugated metabolites of EC were also detected in feces. Fourteen microbially derived phenolic metabolites were also identified in feces, cecal content, and/or colonic tissue. These results show that during transit along the digestive tract, proanthocyanidin oligomers and polymers are depolymerized into EC units. After ingestion of GADF, free EC and its conjugates, as well as free and conjugated microbially derived phenolic metabolites, come into contact with the intestine epithelium for more than 24 h and may be partly responsible for the positive influence of GADF on gut health.  相似文献   
335.
The antioxidant properties of seven dessert spices (anise, cinnamon, ginger, licorice, mint, nutmeg, and vanilla) were compared with those of the common food antioxidants butylated hydroxyanisole (BHA) (E-320), butylated hydroxytoluene (BHT) (E-321), and propyl gallate (E-310). The influence of irradiation process on antioxidant activity was also evaluated. Mint and cinnamon exhibited a higher percentage of inhibition of oxidation than the other spices analyzed and the food antioxidants, as tested by the lipid peroxidation assay (LOO*). Nutmeg, anise, and licorice showed the strongest protection in the deoxyribose assay (OH*). Vanilla exhibited the highest antioxidant activity in the peroxidase-based assay (H2O2). Nutmeg, propyl gallate, ginger, and licorice improved the stability of oils (sunflower, corn, and olive) and fats (butter and margarine) against oxidation (110 degrees C Rancimat). Cinnamon was a better superoxide radical scavenger than the other analyzed spices and additives. When the Trolox equivalent antioxidant capacity (TEAC) assay was used to provide a ranking order of antioxidant activity, the result in decreasing order of antioxidant capacity was cinnamon approximately equal to propyl gallate > mint > anise > BHA > licorice approximately equal to vanilla > ginger > nutmeg > BHT. Irradiated samples did not show significant differences (p < 0.05) in the antioxidant activity with respect to the non-irradiated samples (1, 3, 5, and 10 kGy) in the assays used.  相似文献   
336.
Total and individual glucosinolate (GSL) content of leaves of vegetable turnip rape (Brassica rapa L. var. rapa) was determined in a set of 45 varieties consisting in early, medium and late types grown at two locations in northwestern Spain. The objectives were to determine the diversity among varieties in GSL content and to relate that variation with earliness and plant habit. Eight GSL were identified, being two aliphatic GSL, gluconapin (84.4?% of the total GSL) and glucobrassicanapin (7.2?% of the total GSL) the most abundant. Indolic and aromatic GSL content were low but also showed significant differences among varieties. Differences in total and individual GSL content were found among varieties, plant habit groups, and earliness groups. Total GSL content ranged from 19 to 37.3???mol?g?1?dw in early and extra-late groups, respectively, and from 19.5 to 36.3???mol?g?1?dw for turnips and turnip greens groups, respectively. These differences were consistent to values found for gluconapin content where the turnip group had the highest values (31.8???mol?g?1?dw) and the turnip top group had the lowest (15.7???mol?g?1?dw). Two varieties, MBG-BRS0429 and MBG-BRS0550 (from turnip greens and extra-late groups) and MBG-BRS0438 (from turnips and late groups), stood out as they had the highest total GSL content and could be used as a good source of these beneficial bioactive compounds. Elucidation of genetic diversity among crops can provide useful information to assist plant breeders to design improved breeding strategies in order to obtain varieties rich on GSL.  相似文献   
337.
This study aims to determine the presence of extended-spectrum (ESBL) and plasmidic class C beta-lactamase-producing Enterobacteriaceae in poultry, pig and rabbit farms of Catalonia (Spain). PFGE typing showed a low clonal relationship among strains carrying these mechanisms of resistance. Ninety-three percent of them were resistant to two or more of the non-beta-lactam antimicrobials tested and harboured ESBL and plasmidic class C beta-lactamases. Greater diversity of these enzymes was found in strains from poultry farms, the CTX-M-9 family, especially CTX-M-14, with CMY-2 being the most frequent. The isolation of TEM-52 and SHV-2-producing Escherichia coli strains from these animal farms is noteworthy. In contrast, 73% of the strains from pig farms had CTX-M-1, and neither the CMY-type nor CTX-M-9 family enzyme was found. Likewise, it is the first time that CTX-M-1 and SHV-5 encoding strains have been isolated in pigs. On the other hand, in rabbit farms CTX-M-9 family was also the most frequent, being detected in three of a total of four strains. The last one showed a CMY-2, for the first time detected in these animals, too. In conclusion, commensal E. coli strains of food-producing animal farms are a reservoir of ESBL and plasmidic class C beta-lactamases.  相似文献   
338.
ObjectiveTo compare the cardiorespiratory effects and quality of induction of and recovery from anaesthesia following etomidate or alphaxalone-HPCD IV.Study designRandomized ‘blinded’ cross-over study. Twenty-four hours was allowed between phases.AnimalsEight healthy adult Beagles (four male, four female).MethodsDogs were anaesthetized with sevoflurane for instrumentation, then allowed to awake. They then received etomidate (treatment E) or alphaxalone-HPCD (treatment A) intravenously to effect. Heart rate (HR), body temperature, invasive arterial pressures (AP), systemic vascular resistance index (SVRI), stroke volume index, cardiac index (CI), contractility, respiratory rate, central venous pressure, and capnometry were obtained before anaesthetic induction (baseline), 30 seconds and 1 minute after induction, after intubation, one minute after intubation, and for every 5 minutes afterwards until the dog began to swallow and the trachea was extubated. Arterial bloods were taken for analyses before induction, after intubation and every 10 minutes thereafter. The dogs breathed room air. The quality of induction of and recovery from anaesthesia were scored categorically. Statistical analyses used anova for repeated measures, paired t-tests or Wilcoxon signed rank-test as relevant. Significance was set at p < 0.05.ResultsThe induction doses required were (mean ± SD) 2.91 ± 0.41 mg kg?1 and 4.15 ± 0.7 mg kg?1 for treatment E and A respectively. No significant changes in cardiovascular parameters were observed with treatment E. Treatment A resulted in statistically significant increases in HR and CI and reductions of APs and SVRI. Time to extubation was longer with treatment A (25 ± 7 minutes) than with treatment E (17 ± 4 minutes). Dogs became hypoxic with both treatments. The quality of induction and recovery were excellent with treatment A, but significantly less satisfactory with treatment E (recovery score, treatment E median 1, range 0–2; treatment A median 0, range 0–1).Conclusions and clinical relevanceAlphaxalone-HPCD caused significant tachycardia and increase in CI, and statistically (but not clinically) significant decreases in APs and SVRI. Etomidate caused no statistically significant cardiovascular changes. Quality of recovery was better with alfaxalone-HPCD. Both agents caused short-lived hypoxia, and oxygen supplementation is advisable.  相似文献   
339.
Cabrita MT  Vale C  Rauter AP 《Marine drugs》2010,8(8):2301-2317
Marine algae produce a cocktail of halogenated metabolites with potential commercial value. Structures exhibited by these compounds go from acyclic entities with a linear chain to complex polycyclic molecules. Their medical and pharmaceutical application has been investigated for a few decades, however other properties, such as antifouling, are not to be discarded. Many compounds were discovered in the last years, although the need for new drugs keeps this field open as many algal species are poorly screened. The ecological role of marine algal halogenated metabolites has somehow been overlooked. This new research field will provide valuable and novel insight into the marine ecosystem dynamics as well as a new approach to comprehending biodiversity. Furthermore, understanding interactions between halogenated compound production by algae and the environment, including anthropogenic or global climate changes, is a challenging target for the coming years. Research of halogenated metabolites has been more focused on macroalgae than on phytoplankton. However, phytoplankton could be a very promising material since it is the base of the marine food chain with quick adaptation to environmental changes, which undoubtedly has consequences on secondary metabolism. This paper reviews recent progress on this field and presents trends on the role of marine algae as producers of halogenated compounds.  相似文献   
340.
Odor volatiles in three major lychee cultivars (Mauritius, Brewster, and Hak Ip) were examined using gas chromatography-olfactometry, gas chromatography-mass spectrometry, and gas chromatography-pulsed flame photometric detection. Fifty-nine odor-active compounds were observed including 11 peaks, which were associated with sulfur detector responses. Eight sulfur volatiles were identified as follows: hydrogen sulfide, dimethyl sulfide, diethyl disulfide, 2-acetyl-2-thiazoline, 2-methyl thiazole, 2,4-dithiopentane, dimethyl trisulfide, and methional. Mauritius contained 25% and Brewster contained 81% as much total sulfur volatiles as Hak Ip. Cultivars were evaluated using eight odor attributes: floral, honey, green/woody, tropical fruit, peach/apricot, citrus, cabbage, and garlic. Major odor differences in cabbage and garlic attributes correlated with cultivar sulfur volatile composition. The 24 odor volatiles common to all three cultivars were acetaldehyde, ethanol, ethyl-3-methylbutanoate, diethyl disulfide, 2-methyl thiazole, 1-octen-3-one, cis-rose oxide, hexanol, dimethyl trisulfide, alpha-thujone, methional, 2-ethyl hexanol, citronellal, (E)-2-nonenal, linalool, octanol, (E,Z)-2,6-nonadienal, menthol, 2-acetyl-2-thiazoline, (E,E)-2,4-nonadienal, beta-damascenone, 2-phenylethanol, beta-ionone, and 4-vinyl-guaiacol.  相似文献   
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