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131.
The objective of this work was to quantify the flavonoids present in foods most commonly consumed by the Brazilian population. The predominant flavonoids found in largest abundance in all of the analyzed vegetables were glycosides of quercetin. In lettuce, a small amount of luteolin was also detected. In sweet pepper, quercetin and luteolin were both present. White onion [48-56 mg/100 g of fresh weight (FW), expressed as aglycon], red onion (40-100 mg/100 g of FW), red lettuce (67-67.2 mg/100 g of FW), arugula (41-118 mg/100 g of FW), and chicory (18-38 mg/100 g of FW) were highest in total flavonoids. In fruits, the highest concentrations of flavonoids were found in the peel (125-170 mg/100 g of FW) and pulp (35-44 mg/100 g of FW) of oranges and in some apple varieties (14-36 mg/100 g of FW). Variability in flavonoid content due to time of harvesting was high for leafy vegetables and red onions. The estimated ingestion by Brazilian population ranged from 60 to 106 mg/day.  相似文献   
132.
Sixteen novel and ten known galactolipids have been isolated and characterized from the leaves of Ipomoea batatas L. (sweet potato) using an analytical method based on high-performance liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight tandem mass spectrometry. Using this technique, the structures and regiochemistries of the fatty acyl groups and the positions of the double bonds on the acyl chains were determined. Sugar moieties were identified by analysis of one- and two-dimensional nuclear magnetic resonance spectra. The positions of the double bonds of polyunsaturated fatty acids were confirmed, and in some cases their geometries determined, by gas chromatography-mass spectrometry. This is the first report of galactolipids in the leaves of sweet potato.  相似文献   
133.
Although an antioxidant mechanism has been involved in the beneficial effects of ferulic acid in human diseases, there are few reports on the antioxidant properties of this compound in isolated membranes and intact cells. Here, we evaluated the ability of ferulic acid in inhibiting lipid peroxidation in rat liver microsomal membranes and reactive oxygen species production in NIH-3T3 fibroblasts, induced by both tert-BOOH and AAPH. We also compared its antioxidant efficiency with that of other antioxidants, such as alpha-tocopherol, beta-carotene, and ascorbic acid, added alone or in combination. Ferulic acid acted as a potent antioxidant in our models, being more effective in protecting from tert-BOOH than from AAPH. Moreover, the compound was the most effective among the antioxidants tested. Synergistic interactions were observed when the compound was used in combination with the other antioxidants, suggesting that they can cooperate in preserving physiological integrity of cells exposed to free radicals.  相似文献   
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To counteract the effects of perinatal hypoxia in piglets, the oral administration of caffeine to sows with induced parturition was evaluated. On day 113 of gestation 9 sows received 27 mg/kg body weight (BW) of caffeine mixed with 200 g of standard diet. The same amount of feed without the addition of caffeine was administered to 9 control sows. Additionally, on day 113 of gestation, all sows were treated by two injections in the perianal area of 1 mg of alfaprostol (at 8:00 am and 14:00 pm), and on the morning of farrowing by 14 IU of oxytocin in the perianal area. Caffeine did not affect BW of piglets and size of litters; however piglets from treated sows showed a higher capacity to adapt to extra-uterine life. Particularly, they showed a greater thermoregulatory ability (P<0.001) and a higher percentage of viability score≥7 compared to piglets from control sows (92% vs. 75%, respectively; P=0.030). Caffeine furthermore reduced the frequency of high serum biopterin values (>80 nmol/L) in piglets born from treated sows (P=0.001). In conclusion, the caffeine orally administered to sows with induced parturition showed a protective effect on the consequences of neonatal hypoxia in tissue ischemia–reperfusion injury in piglets.  相似文献   
137.
Bark beetles are notorious pests of natural and planted forests causing extensive damage. These insects depend on dead or weakened trees but can switch to healthy trees during an outbreak as mass-attacks allow the beetle to overwhelm tree defences. Climatic events like windstorms are known to favour bark beetle outbreaks because they create a large number of breeding sites, i.e., weakened trees and for this reason, windthrown timber is generally preventively harvested and removed. In December 1999, the southwest of France was struck by a devastating windstorm that felled more that 27 million m3of timber. This event offered the opportunity to study large-scale spatial pattern of trees attacked by the bark beetle Ips sexdentatus and its relationship with the spatial location of pine logs that were temporally stored in piles along stand edges during the post-storm process of fallen tree removal. The study was undertaken in a pure maritime pine forest of 1300 ha in 2001 and 2002. We developed a landscape approach based on a GIS and a complete inventory of attacked trees. During this study more than 70% of the investigated stands had at least one tree attacked by I. sexdentatus  . Spatial aggregation prevailed in stands with n≥15n15 attacked trees. Patches of attacked trees were identified using a kernel estimation procedure coupled with randomization tests. Attacked trees formed patches of 500–700 m2 on average which displayed a clumped spatial distribution. Log piles stemming from the sanitation removals were mainly distributed along the large access roads and showed an aggregated spatial pattern as well. The spatial relationship between patches of attacked trees and log pile storage areas was analyzed by means of the Ripley’s statistic that revealed a strong association at the scale of the studied forest. Our results indicated that bark beetle attacks were facilitated in the vicinity of areas where pine logs were stored. The spatial extent of this relationship was >1000 m. Similar results were obtained in 2001 and 2002 despite differences in the number and spatial distribution of attacked trees. The presence of a strong “facilitation effect” suggests that log piles should be removed quickly in order to prevent outbreaks of bark beetles.  相似文献   
138.
Feijoa sellowiana Berg. fruits and especially the acetonic extract have been shown to possess biological activities, although the responsible compounds have never been identified. The present study was designed to evaluate the anti-inflammatory activity of an acetonic extract from F. sellowiana Berg. fruits on the nitric oxide (NO) pathway, which plays an important role in inflammation. To this aim the J774 cell line, which expresses inducible nitric oxide synthase (iNOS) following stimulation with lipopolysaccharide (LPS), has been utilized, and the effects of this extract and its fractions on NO production, iNOS protein expression, and signal pathways involved in its regulation have been evaluated. This study demonstrates that at least some part of the anti-inflammatory activity of the acetonic extract is due to the suppression of NO production by flavone and stearic acid. The mechanism of this inhibition seems to be related to an action on the expression of the enzyme iNOS through the attenuation of nuclear factor kappaB (NF-kappaB) and/or mitogen-activated protein kinase (MAPK) activation.  相似文献   
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Euplotin C is a sesquiterpene of marine origin endowed with significant anti-microbial and anti-tumor properties. Despite the promising functional profile, its progress as a novel drug candidate has failed so far, due to its scarce solubility and poor stability in aqueous media, such as biological fluids. Therefore, overcoming these limits is an intriguing challenge for the scientific community. In this work, we synthesized β-cyclodextrin-based nanosponges and investigated their use as colloidal carriers for stably complex euplotin C. Results obtained proved the ability of the carrier to include the natural compound, showing remarkable values of both loading efficiency and capacity. Moreover, it also allowed us to preserve the chemical structure of the loaded compound, which was recovered unaltered once extracted from the complex. Therefore, the use of β-cyclodextrin-based nanosponges represents a viable option to vehiculate euplotin C, thus opening up its possible use as pharmacologically active compound.  相似文献   
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