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61.
Eduardo Moreno-Jiménez Rebeca Manzano Elvira Esteban Jesús Peñalosa 《Journal of Soils and Sediments》2010,10(2):301-312
Background, aim, and scope
The mobility of arsenic in soils and its transfer to other environmental components present significant environmental risks. The management of polluted land is determined by the availability, mobility, and transfer of inorganic pollutants to different ecosystem compartments. In this paper, the fate of arsenic at this mining site has been evaluated to determine future management practises to minimise such risk. 相似文献62.
The DPPH radical scavenging activity of two flavonol glycosides obtained from ethanolic extracts of Aconitum napellus sp. lusitanicum was studied. The results showed a high DPPH antiradical activity of compound 1 (quercetin 3-O-(6-trans-caffeoyl)-beta-glucopyranosyl-(1-->2)-beta-glucopyranosyl-7-O-alpha-rhamnopyranoside) when compared with compound 2 (quercetin-3-sophoroside-7-rhamnopyranoside), rutin and ascorbic acid. The relationship between the caffeoyl and rhamnopyranoside groups in the flavonol glycosides structures and the DPPH antiradical activity was also discussed. 相似文献
63.
Mato I Huidobro JF Simal-Lozano J Sancho MT 《Journal of agricultural and food chemistry》2006,54(5):1541-1550
A rapid capillary zone electrophoresis (CZE) method with direct ultraviolet (UV) detection has been set up and developed to determine the most important nonaromatic organic acids in honey with a really simple treatment of the sample. The determination of oxalic, formic, malic, succinic, pyruvic, acetic, lactic, citric, and gluconic acids has been carried out in 4 min. The electrolyte composition was phosphate as the carrier buffer (7.5 mM NaH(2)PO(4) and 2.5 mM Na(2)HPO(4)), 2.5 mM tetradecyltrimethylammonium hydroxide (TTAOH) as electroosmotic flow modifier, and 0.24 mM CaCl(2) as selectivity modifier, with the pH adjusted at 6.40 constant value. The running voltage was -25 kV at a thermostated temperature of 25 degrees C. The injections were performed in hydrodynamic mode (30 s), and the detection mode was UV direct at 185 nm. Validation parameters of the method as detection and quantification limits, linearity, precision (repeatability and reproducibility), and recovery were also studied. The advantages related to the technique such as simplicity, short analysis times, and low consumption of chemicals as well as the good validation parameters obtained for this method permit it to be considered as adequate for routine analysis in honey. 相似文献
64.
In the contemporary Amazon, ‘discourse’ is increasingly a new means of exercising power, influencing local society and the ways in which natural resources are managed. As society becomes ever more complex, direct means of exercising power no longer enjoy the same legitimacy and efficacy. Discourses are instead now assuming a dominant role in defining governance regimes; the sense of what is correct and socially acceptable, and what is not. This is particularly relevant for the rapidly advancing development frontiers in the Amazon region, where local communities are coming into contact with external players highly interested in their forest resources. This study focuses on understanding how external discourses can restrict the Amazonian communities' options for using their forests, but also how communities can harness these discourses to achieve their own claims and objectives. Empirical evidence from four study areas in the Bolivian, Brazilian and Peruvian Amazon regions is used to show how discourses on sustainable forest management are moulding forestry governance. The conclusion shows that while the discourses used by loggers and development organisations are strongly influencing the way communities manage their forests, some communities are also successfully using these discourses in alliances with environmental organisations to achieve acknowledgment of their demands. 相似文献
65.
Cuauhtémoc Reyes-Moreno Oscar D. Argüelles-López Jesús J. Rochín-Medina Jorge Milán-Carrillo Javier Rivera-López Angel Valdez-Ortiz José A. López-Valenzuela Roberto Gutiérrez-Dorado 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(4):450-456
The objective of this study was to determine the best combination of extrusion process variables for the production of whole quality protein maize (EQPMF) and common bean (ECBF) flours to prepare a high antioxidant activity mixture (EQPMF + ECBF) suitable to produce a nutraceutical beverage with high acceptability elaborated with a traditional Mexican formulation. Processing conditions were obtained from a factorial combination of barrel temperature (BT?=?120–170 °C) and screw speed (SS?=?120–200 rpm). Response surface methodology was applied to obtain maximum values for antioxidant activity (A ox A) of the flour mixture (EQPMF + ECBF) and acceptability (A) of the nutraceutical beverage. The best combinations of extrusion process variables for EQPMF and ECBF to prepare an optimized mixture (60%EQPMF?+?40%ECBF) were BT?=?98 °C/SS?=?218 rpm and BT?=?105 °C/SS?=?83 rpm, respectively. The optimized mixture had A ox A?=?14,320 μmol Trolox equivalent (TE)/100 g sample dry weight (dw) and a calculated protein efficiency ratio (C-PER) of 2.17. A 200 ml portion of a beverage prepared with 25 g of the optimized flour mixture had A ox A?=?3,222 μmol TE, and A?=?89 (level of satisfaction “I like it extremely”). This nutraceutical beverage could be used as an alternative to beverages with low nutritional/nutraceutical value, such as those prepared with water, simple sugars, artificial flavoring and colorants, which are widely offered in the market. 相似文献
66.
Piedad S Morillo‐Velarde Jesús Cerezo Valverde Rosa M Serra Llinares Benjamín García García 《Aquaculture Research》2013,44(8):1177-1189
In this work, we study the variations in concentration (mg 100 g?1 dry weight) and total content (mg individual?1) of different lipid classes in muscle and the digestive gland of Octopus vulgaris during an 8‐day starvation period. In all the samples analysed, polar lipids (PL) predominated in muscle (267.3–337.2 mg 100 g?1) compared with neutral lipids (66.9–104.7 mg 100 g?1). A significant positive tendency was observed in muscle for the content and concentration of monoglycerides as a consequence of starvation (P < 0.05). Furthermore, a higher cholesterol (CHO) content was detected in this tissue after the fourth day of starvation compared with the fed animals (P < 0.05). Neutral lipids predominated in the digestive gland (12 958–14 151 mg 100 g?1) compared with PL (3157–6517 mg 100 g?1), with triglycerides, free fatty acids and monoglycerides being the major lipid classes. The concentration of PL and monoglycerides showed a positive trend with starvation, while the triacylglycerol showed a negative tendency (P < 0.05). The results suggest that triglycerides and CHO are transported simultaneously from the digestive gland to the muscular tissues during starvation and the preferential use of PL and CHO during growth phases. It was estimated that lipids contributed 26% of the energy costs of the animals during starvation, mainly in the form of triglycerides from the digestive gland. 相似文献
67.
Álvaro González Jesús D. Celada Pedro M. Melendre José M. Carral María Sáez‐Royuela Rocío González Vanesa García 《Aquaculture Research》2013,44(3):354-358
Two experiments were conducted on the effects of bronopol in the artificial incubation of crayfish eggs (Pacifastacus leniusculus) with the aim to search an alternative to formaldehyde. In the first experiment, 50, 250, 500 and 1000 ppm bronopol and 3000 ppm formaldehyde (control) in periodical administrations were tested on a density of 6.6 eggs cm?2. After 44 days of incubation, the highest survival was obtained with 1000 ppm bronopol (81.9% to stage 2 juvenile, with no significant difference from formaldehyde), whereas lower bronopol concentrations resulted in significantly lower survival. In the second experiment, 1000, 3000 and 5000 ppm bronopol and 3000 ppm formaldehyde (control) administered for 15 min every second day were tested on eggs at a density of 20 eggs cm?2. After 78 days of incubation, bronopol at 3000 ppm allowed for a stage 2 juvenile survival rate of 65.0% (with no significant difference from formaldehyde), whereas significantly lower survival was obtained with 1000 ppm or 5000 ppm. This study shows that bronopol may constitute an alternative to formaldehyde in the artificial incubation of crayfish eggs. A concentration of 3000 ppm administered for 15 min every second day may be adequate even on long incubations at high densities (at least 20 eggs cm?2, one complete layer). 相似文献
68.
Jesús Cerezo Valverde María Dolores Hernández Felipe Aguado‐Giménez Piedad S Morillo‐Velarde Benjamín García García 《Aquaculture Research》2013,44(12):1952-1964
Growth, feed efficiency and proximate and lipid class composition of subadults Octopus vulgaris (788 ± 133 g; 18.5°C) fed formulated diets of low lipid (LL: 8 g kg?1) and high lipid levels (HL: 84 g kg?1) and each one of these with three different levels of glutamate supplementation (0, 5 and 20 g kg?1) were compared. All the animals accepted the diets with a survival of 100%. The addition of glutamate did not stimulate feeding rates in any of the assays (2.48–2.64 and 1.86–2.01%Body weight day?1 for LL and HL, respectively; P > 0.05). The best growth, feed efficiency and protein productive value were observed in the groups fed 5 or 20 g kg?1 glutamate supplementation at both lipid levels, with significant differences for LL diet (P < 0.05). A better feed efficiency was achieved with the HL diet (14.6–27.5% vs. 2.5–19.2% for LL diet). There were no significant differences in the proximate composition of carcass (animal excluding the digestive gland). However, a substantial amount of lipids accumulated in the digestive gland, mainly triglycerides, was detected as a consequence of higher lipid ingestion or glutamate supplementation. It was notable the lower percentages of phosphatidylethanolamine and phosphatidylcholine in the digestive gland of animals with best growth. 相似文献
69.
Carlos Garrido María Carbú Francisco Javier Fernández-Acero Giles Budge Inmaculada Vallejo Alison Colyer Jesús M. Cantoral 《European journal of plant pathology / European Foundation for Plant Pathology》2008,120(4):409-415
Anthracnose, caused by Colletotrichum spp., is a major disease of cultivated strawberry, Fragaria × ananassa. This study identifies the Colletotrichum spp. which causes strawberry anthracnose in the southwest of Spain. A survey of the region was carried out, and the strains
isolated were identified as C. acutatum by using the polymerase chain reaction (PCR) with genus and species-specific primers, demonstrating that this species is
currently the causal agent of strawberry anthracnose in the studied region. The pathogenicity of C. acutatum and C. gloeosporioides strains was evaluated on two principal strawberry cultivars (cvs Camarosa and Ventana) under field conditions, the latter
being more pathogenic than the former. 相似文献
70.
Nadia Korolev Encarnación Pérez-Artés Jesús Mercado-Blanco José Bejarano-Alcázar Dolores Rodríguez-Jurado Rafael M. Jiménez-Díaz Talma Katan Jaacov Katan 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(4):603-617
Verticillium dahliae isolates recovered from a new focus of severe Verticillium wilt of cotton in the northeast of Israel were tested for vegetative
compatibility using nitrate non-utilizing (nit) mutants and identified as VCG1, which is a new record in Israel. Other cotton isolates of V. dahliae from the northern and southern parts of the country were assigned to VCG2B and VCG4B, respectively. VCG1 isolates induced
severe leaf symptoms, stunting and defoliation of cotton cv. Acala SJ-2, and thus were characterized as the cotton-defoliating
(D) pathotype, whereas isolates of VCG2B and VCG4B were confirmed as the earlier described defoliating-like (DL) and non-defoliating
(ND) pathotypes, respectively. This is the first record of the D-pathotype in Israel. The host range of representative isolates
of each VCG-associated pathotype was investigated using a number of cultivated plants. Overall, the D isolates were more virulent
than DL isolates on all tested host plants, but the order of hosts (from highly susceptible to resistant) was the same: okra
(Hibiscus esculentus local cultivar), cotton (Gossypium hirsutum cv. Acala SJ2), watermelon (Citrullus lanatus cv. Crimson Sweet), safflower (Carthamus tinctorius cv. PI 251264), sunflower (Helianthus annuum cv. 2053), eggplant (Solanum melongena cv. Black Beauty), and tomato (Lycopersicon esculentum cv. Rehovot 13). The pattern of virulence of ND isolates differed from that of D and DL isolates, so that the former were
highly virulent on eggplant but mildly virulent on cotton. Tomato was resistant to all cotton V. dahliae isolates tested. RAPD and specific PCR assays confirmed that the D isolates from Israel were similar to those originating
from other countries. 相似文献