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171.
172.
Pérez-López AJ López-Nicolas JM Núñez-Delicado E Del Amor FM Carbonell-Barrachina AA 《Journal of agricultural and food chemistry》2007,55(20):8158-8164
Consumers demand organic products because they believe they are more flavorful and respectful to the environment and human health. The effects of conventional, integrated, and organic farming, grown in a controlled greenhouse, on color, minerals, and carotenoids of sweet pepper fruits ( Capsicum annuum), cv. Almuden, were studied. Experimental results proved that organic farming provided peppers with the highest (a) intensities of red and yellow colors, (b) contents of minerals, and (c) total carotenoids. Integrated fruits presented intermediate values of the quality parameters under study, and conventional fruits were those with the lowest values of minerals, carotenoids, and color intensity. As an example, the concentrations of total carotenoids were 3231, 2493, and 1829 mg kg (-1) for organic, integrated, and conventional sweet peppers, respectively. Finally, organic red peppers could be considered as those having the highest antioxidant activity of all studied peppers (agricultural farming and development stage). 相似文献
173.
Maintaining connectivity among local populations in a fragmented landscape is crucial for the survival of many species. For
isolated habitat patches, stochastic fluctuations and reduced gene flow can lead to high risk of extinction. The connectivity
of the landscape is especially crucial for the carabid species living in the fragmented forests of the Bereg plain (NE Hungary
and W Ukraine) because a highway will be constructed through the plain. Our purpose is to (1) evaluate the impacts of three
possible highway tracks, (2) suggest a solution that is realistic with less impact on connectivity than other plans and (3)
discuss how to decrease the disadvantageous effects of each track. Our results, based on a network analysis of landscape graph
of patches and ecological corridors, indicate that the intended highway could have deleterious consequences on forest-living
carabids. Relatively simple actions, like the establishment of stepping stones, could compensate for the loss of habitat connectivity
and promote the survival of carabids, or minor modifications in one possible track could diminish its adverse effects. While
many other studies would be needed for a comprehensive assessment of the biotic impact of the highway, we provide an example
on the usefulness of network analysis for land use management.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
174.
Maria Pukalchik Maria Panova Mikhail Karpukhin Olga Yakimenko Kamila Kydralieva Vera Terekhova 《Journal of Soils and Sediments》2018,18(3):750-761
Purpose
Heavy metal contamination is a priority issue affecting millions of hectares of soil throughout the world. One of the most promising, environmentally friendly, and cost-effective approaches to restore polluted soils could be applying organic amendments. We investigated the remediation potential of three types of humic products with regard to their effect on the bioavailability of Pb and Zn, content of nutrients, and the ability to mitigate acute phytotoxicity in contaminated soil.Materials and methods
Spodosol samples were spiked with Pb (550 mg kg?1) and Zn (880 mg kg?1). Then, two different commercial humic products (from peat and lignosulfonate) and natural humic acids (from brown oxidized coal) were added in two doses to reach an equal content of carbon: a 10% increment and a 30% increment of the initial total organic carbon in the soil. After 30 days, the content of metals and nutrients (S, K, Na, Ca, Mn, P) was determined by the sequential extraction (i?H2O, ii?NH4COOH pH 4.8, iii–CH3COOH). The effect of humic products on heavy metals bioavailability was evaluated using the calculated partition indexes. Seed germination and root elongation of Sinapis alba were also determined. Chemical and biochemical variables were aggregated by the principal component analysis.Results and discussion
Humic products reduced the amount of bioavailable fractions of Pb and Zn in soils. The partition index, which quantitatively describes bioavailable fractions of the Zn and Pb in the soil, was 28–49% lower than in the spiked (Pb+Zn) control. The inhibition of root elongation and seed germination of mustard by Zn and Pb was significantly mitigated by humic products; in the soil test, the root length and seed germination were up to 36–87% higher than those of the Pb+Zn control and did not differ from those in the non-amended treatments. This effect may have been associated with the structural differences (H/C and O/C ratio) and content of nutrients (Na and K) in humic products.Conclusions
Commercial humic products used in poor multi-contaminated soils can maintain plant growth by improving nutrient status due to heavy metals immobilization and can be a promising approach to remediate the soil contaminated with heavy metals at extremely high concentrations.175.
Granado-Lorencio F Donoso-Navarro E Sánchez-Siles LM Blanco-Navarro I Pérez-Sacristán B 《Journal of agricultural and food chemistry》2011,59(21):11819-11824
Bioactive compounds are used in the design and development of new food products with potential health benefits, although little is known regarding their bioavailability and interactions. This study assessed the stability, in vitro bioaccessibility, and human bioavailability of β-cryptoxanthin from β-cryptoxanthin-rich drinks with and without added phytosterols developed for this purpose. The developed drinks showed no difference in the content of β-cryptoxanthin, and they were stable over 6 months. In vitro, hydrolysis of β-cryptoxanthin esters and the amount of free β-cryptoxanthin at duodenal and micellar phases were similar regardless of the presence of phytosterols. In the human study, the daily intake provoked significant increments of β-cryptoxanthin in serum regardless of the type of the drink. In conclusion, in vitro and in vivo human studies have shown that the bioavailability of β-cryptoxanthin is not significantly affected by the presence of phytosterols when they are simultaneously supplied in a drink. 相似文献
176.
Eduardo da Silva Manuel Aldegunde Deivisson Ferreira da Silva Carlize Lopes Fabiano Cleber Bertoldi Robilson Antnio Weber 《Aquaculture Research》2020,51(2):577-583
This study aimed to determine the lowest effective concentration (LEC) of 2‐phenoxyethanol (2‐Phe) and essential oils (EOs) of Melaleuca alternifolia and Ocimum gratissimum able to induce anaesthesia in Astyanax bimaculatus. LEC was assumed to be the required concentration to carry out anaesthesia in less than 3 min with recovery in <5 min and sufficient to carry out routine aquaculture procedures. The following concentrations were tested: 2‐Phe (100, 200, 300, 400, 500 and 600 µl/L); M. alternifolia (200, 300, 400, 500 and 600 µl/L); and O. gratissimum (10, 20, 30, 40, 50, 60, 70, 100, 150, 250 and 300 µl/L). Results show that all three agents evaluated have effective anaesthetic properties for use in Astyanax bimaculatus with LEC for 2‐Phe, M. alternifolia and O. gratissimum of 200, 300 and 60 µl/L respectively. 相似文献
177.
Rafael Ginés Juan Manuel Afonso Anastasio Argüello María Jesús Zamorano & Juan Luis López 《Aquaculture Research》2004,35(13):1207-1212
Immature gilthead sea bream (Sparus aurata L.) with a mean initial weight of 25.6 g were reared over 11 months to market size under different photoperiods: 16L:8D; 24L:0D and a control. Differences in final mean weight were significant between the three treatments (P<0.001): 16L:8D, 465.0 g; 24L:0D, 445.9 g; control, 402.6 g. Fish from the 24L:0D consumed most while 16L:8D fish converted it most efficiently. The lipid content of fillets was lower (P<0.05) for the 24L:0D (5.37±0.16 g 100 g?1 of fillet) than for the control (6.02±0.12 g), and the moisture content lower for the control than for either treatment groups. Skin luminosity (L*) was directly related to the number of hours of light exposure. 相似文献
178.
179.
Celia Barbero-Sierra Manuel Ruíz Pérez María José Marqués Pérez Ana María Álvarez González José Luis Cruz Maceín 《Arid Land Research and Management》2018,32(1):111-129
Farmers’ land management is a key factor for sustainable agriculture, yet the traditional knowledge which constitutes its base is seldom incorporated in the land and soil academic literature. The need for a hybrid approach that combines local (farmers’) and scientific knowledge is formally recognized. Plot quality criteria are a component of both sources of knowledge, playing an important role in shaping land management practices. Yet there are few case studies comparing the criteria used by farmers and soil scientists when assessing plot quality, particularly in developed countries. We compare the plot quality assessment done by a sample of 31 farmers in a semiarid area of Spain with an edaphic quality index (EQI) obtained through laboratory analyses of soil samples from 61 farm plots. There is a coincidence between farmer and laboratory assessments in 70% of cases. Plots identified by farmers as being of good quality have a significantly higher EQI than those identified as bad quality. The two key differentiating parameters were clay content (average 21% in good versus 18% in bad quality plots) and soil organic carbon content (1.6 and 1.3%, respectively), both closely related to soil water retention ability. A holistic land vision, a higher level of education and large differences in EQI between good and bad plots as assessed by farmers have a positive influence in the degree of coincidence between farmers’ and laboratory assessments. 相似文献
180.
Marina Hidalgo Isabel Prieto Hikmate Abriouel Ana Belén Villarejo Manuel Ramírez-Sánchez Antonio Cobo Nabil Benomar Antonio Gálvez Magdalena Martínez-Cañamero 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(1):1-6
Fat type in diet is responsible for specific changes in gut microbiota (GM). Extra virgin olive oil (EVOO) has been shown to be beneficial for blood pressure and to produce effects on GM. To analyze the cause-effect relationship between intestinal microbial changes and blood pressure, we studied the effect of EVOO on fecal microbiota and systolic blood pressure (SBP) levels in spontaneously hypertensive rats (SHR). SHR were fed either an enriched EVOO diet or a standard diet for a period of 12 weeks. At the end of the experimental period, the microbial profiles in the feces were studied in both groups by using PCR-denaturing gradient gel electrophoresis. Real-time PCR was used to quantify the selected bacterial groups. The results demonstrated significant differences when using Lactobacillus (p<0.05), clostridia XIV (p<0.01) and universal (p<0.05) primers. A significant (r=?0.475; p=0.04) inverse correlation between the abundance of clostridia XIV and SBP, which depends on the type of diet, was also observed. Finally, the results suggested an increase in the microbial diversity of the feces of the animals fed the EVOO diet. These results strongly connect the pattern of GM in SHR fed a diet enriched with EVOO to the lower levels of SBP observed in these animals at the end of the feeding period. 相似文献