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1.
There is a great interest in the nutritional value of vegetables and fruits and how the habitat affects nutritive and biological properties. In vitro studies here reported were performed to evaluate the inhibitory activity of formulations from edible plant on pancreatic lipase. The aim of this study was also to evaluate the biovariability of L. comosa (L.) Parl. bulbs from Italy. The wild bulbs were compared with the same cultivated species that are commonly commercialized to identify samples with the best quality for a potential therapeutic application. Hydroalcoholic extract and polar fraction of wild bulbs showed a very important pancreatic lipase inhibitory activity, with IC50 values of 0.166 ± 0.005 and 0.153 ± 0.005 mg/mL, respectively. In order to characterize the extracts, gas chromatography associated with mass spectrometry (GC/MS) analysis was performed, revealing the predominance of palmitic acid. Phenolic and flavonoid composition was also evaluated. L. comosa extract obtained from wild bulbs demonstrated both antioxidant and anti-obesity activities that might be attributed to a wide range of present phenolic compounds.  相似文献   
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Factors shaping individual behavior remain poorly understood for European cyprinids. We examined the effects of extrinsic (temperature and year) and intrinsic factors (body size and shoal size) on the daily activity of chub Squalius torgalensis, a critically endangered cyprinid found in the Torgal stream, Portugal. We quantified chub behaviors while snorkeling, using instantaneous sampling of focal individuals, in spring 2009 and 2010. We used Principal Component Analysis to describe individual behavior and assessed competing models relating individual behavior to explanatory variables using Akaike's Information Criterion. Year had a strong influence on chub behavior, with individuals spending more time drift foraging and orienting in 2009, whereas in 2010 they spent more time benthic foraging and cruising. Shoal size did not influence behaviors in 2009, but in 2010 individuals in small shoals foraged benthically and searched with greater frequency than those in large shoals. Individuals increased cruising and decreased searching as they grew in length, but the opposite trend was observed as temperature increased. Our results indicate that both extrinsic and intrinsic factors influence daily activity of chub, with individual behaviors varying between years, and depending upon shoal size, body size and temperature. This suggests that chub display high levels of individual behavioral flexibility, which may be important for fish inhabiting harsh and highly variable Mediterranean streams. Conservation efforts for this species will benefit by integrating behavioral information into management strategies.  相似文献   
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The effects of four pesticides (three herbicides, atrazine, paraquat, glyphosate, and an insecticide, carbaryl) on the activity and kinetics of an invertase (from yeast), a urease (from jack bean) and an acid phosphatase (from potato) were investigated. Glyphosate and paraquat showed a marked activation effect on invertase activity. From the dependence of Vmax and Km parameters on pesticide concentrations, a mixed-type activation mechanism was suggested. The kinetic behaviour of urease and acid phosphatase appeared to be uninfluenced by both pesticides. Methanol, used as solvent for both carbaryl and atrazine, inhibited invertase, urease and acid phosphatase with, respectively, competitive, non-competitive and uncompetitive mechanisms. The extent of the inhibition was different, as estimated by the values of the inhibition constant K1. An additional inhibition effect of urease and invertase activities was achieved in the presence of carbaryl, whereas no influence was detected on the activity and kinetics of acid phosphatase. Finally, atrazine was shown to alter the kinetics of the enzymes only at higher concentrations.  相似文献   
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The methanol and ethyl acetate extracts of the aerial parts of Cirsium tenoreanum, have been evaluated for their phytochemical constituents and antibacterial and cytotoxic properties. Three flavonoids, apigenin, quercetin-3-O-galactoside and kaempferol-3-O-ramnoside, were isolated. The ethyl acetate extract showed a good antiproliferative activity.  相似文献   
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OBJECTIVE: Public health professionals continue to see the benefits of fruit and vegetable consumption on population health. While studies that evaluate the availability of produce are sparse in the medical literature, disparities in availability may explain the disproportional intake of produce for some people. Therefore, the purpose of this study was to evaluate the availability and variety of produce located in two racially and economically diverse urban neighbourhoods. DESIGN: A cross-sectional study was conducted in which 50% of the supermarkets, small grocery stores, delicatessens, and fruit and vegetable markets located in specific neighbourhoods were randomly sampled and surveyed between September 2004 and July 2005. Food stores were evaluated for the availability of 20 types of fresh fruits and 19 types of fresh vegetables, as well as their varieties and whether they were canned, frozen or previously prepared. 2000 US Census information was used to determine characteristics of the geo-coded census tracts where the food stores were located. SETTING: Brooklyn, New York. RESULTS: A supermarket was located in approximately every third census tract in predominantly white areas (prevalence = 0.33) and every fourth census tract in racially mixed areas (prevalence = 0.27). There were no supermarkets located in the predominantly black areas. With the exception of bananas, potatoes, okra and yucca, a lower proportion of predominantly black area stores carried fresh produce, while supermarkets carried the largest variety of produce types. Canned and frozen fruits and vegetables were found in the majority of stores, whereas prepared and organic produce was limited to predominantly white area stores. CONCLUSIONS: These data demonstrate that the availability and variety of fresh produce is associated with neighbourhood racial composition and may be a factor contributing to differences in intake among residents.  相似文献   
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Barbela is an old Portuguese landrace of wheat that is highly genetically heterogeneous. Different Barbela populations when subjected to aluminium stress show variable levels of tolerance. In order to study the inheritance of this character, doubled haploid (DH) lines were developed. These DH were obtained by intergeneric crosses of 14 different lines of Barbela with maize. During this process the efficiency of the technique was evaluated and suggestions for its improvement were obtained. Several parameters were studied in the crosses: % of crossability, % of embryos per florets pollinated and % of embryos per seed set. The different genotypes of Barbela showed significant variation for the parameters analysed. When the reciprocal crosses were analysed, no differences were found, indicating that cytoplasm differences do not influence the parameters of DH production. However, different spikelet positions (lower, middle and upper) gave highly significant differences in all parameters analysed. Highest success frequencies were obtained for pollinated spikelets in the middle of the spike. This can indicate that concentrating on the middle part of the spike can increase the frequency of DHs obtained using inter generic crosses of wheat with maize. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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Meroterpenes are widely distributed among marine organisms; they are particularly abundant within brown algae, but other important sources include microorganisms and invertebrates. In the present review the structures and bioactivities of meroterpenes from marine invertebrates, mainly sponges and tunicates, are summarized. More than 300 molecules, often complex and with unique skeletons originating from intra- and inter-molecular cyclizations, and/or rearrangements, are illustrated. The reported syntheses are mentioned. The issue of a potential microbial link to their biosynthesis is also shortly outlined.  相似文献   
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Adsorption–desorption characteristics of 2,4-dichlorophenoxyacetic acid (2,4-D) on pure montmorillonite and synthetic chlorite-like complexes [Al(OH)x-montmorillonite complexes, obtained by coating montmorillonite surfaces with different amounts of Al(OH)x] were investigated. The equilibrium adsorption of 2,4-D was described by both Langmuir and Freundlich type isotherms. The extent of adsorption as well as the type of interaction between adsorbate and adsorbent was affected by the nature of incubation buffer and the charge characteristics of supports. At pH 5·6 and in acetate buffer, 2,4-D was negatively adsorbed by montmorillonite and herbicide adsorption capacity increased with increasing amounts of Al(OH)x species loaded on montmorillonite surfaces. When adsorption experiments were performed at the same pH but in phosphate buffer, strong reductions of both the amount of adsorbed pesticide and its affinity for the adsorbents were measured. Evidently, phosphate anions competed strongly with 2,4-D anions for the sorption site on chlorite-like complexes. Furthermore, desorption tests revealed that a large amount (about 60%) of the pesticide was firmly bound to the clay and was not removed even after repeated washings or 24 h exposure to desorption solution. Both electrostatic interactions between the negative COO- moieties of 2,4-D and the positive sites on clays, and ligand exchanges of COO- groups with -OH or water at the clay surface were probably involved in the adsorption process. ©1997 SCI  相似文献   
10.
Epidemiological studies have shown a relation between antioxidants and the prevention of several chronic diseases. Microalgae are a potential novel source of bioactive molecules, including a wide range of different carotenoids that can be used as nutraceuticals, food supplements and novel food products. The objective of this review is (i) to update the research that has been carried out on the most known carotenoids produced by marine microalgae, including reporting on their high potentialities to produce other less known important compounds; (ii) to compile the work that has been done in order to establish some relationship between carotenoids and oxidative protection and treatment; (iii) to summarize the association of oxidative stress and the various reactive species including free radicals with several human diseases; and (iv) to provide evidence of the potential of carotenoids from marine microalgae to be used as therapeutics to treat or prevent these oxidative stress-related diseases.  相似文献   
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