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181.
Luis A. Bello‐Prez Pamela C. Flores‐Silva Gustavo A. Camelo‐Mndez Octavio Paredes‐Lpez Juan de Dios Figueroa‐Crdenas 《Cereal Chemistry》2015,92(3):265-270
Nixtamalization is an ancient process developed by the Mesoamerican cultures. Initially, volcanic ashes were used and then calcium hydroxide in commercial production, and more recently nixtamalization with calcium salts (NCS) has been proposed. The aim of this study was to evaluate the effect of NCS on carbohydrate digestibility and antioxidant capacity in the elaboration of blue maize tortillas. NCS in blue tortillas showed a high amount of total dietary fiber (14.27 g/100 g), the main fraction being insoluble dietary fiber. The contents of resistant starch and slowly digestible starch did not change with the nixtamalization process. The predicted glycemic index value was lower in blue tortillas with the NCS process (58) than with the traditional nixtamalization process (71). In general, NCS in blue tortillas presented a higher antioxidant capacity than traditional tortillas (ferric reducing antioxidant power method), indicating that phenolics present in blue maize maintain their activity after cooking. It can be concluded that the nutraceutical features (high dietary fiber content and antioxidant capacity) of blue maize tortillas are enhanced when they are elaborated with the NCS process. 相似文献
182.
Patrizia Erre Innocenza Chessa Concepción Muñoz-Diez Angjelina Belaj Luis Rallo Isabel Trujillo 《Genetic Resources and Crop Evolution》2010,57(1):41-54
The genetic relationships within and between wild and cultivated olives were examined and clarified in an isolated and restricted
area, such as the Mediterranean island of Sardinia. Wild (21 individuals) and cultivated olive trees (22 local cultivars from
a germplasm collection and 35 ancient trees) were genotyped by means of 13 SSR loci. Five cases of synonymy were observed
and nine distinct genotypes were identified in the collection. Five novel genotypes were also detected among the ancient trees.
Differences on the allelic composition and heterozygosity levels were found between wild and cultivated trees. Model-based
clustering method classified the olive trees into two major gene pools: (a) wild genotypes and (b) local cultivars from the
collection and from heritage olives. Regarding the cultivated plant material, we observed that: (a) most of the Sardinian
cultivars shared the same allelic profiles with the ancient cultivated trees and (b) the majority of these cultivars and all
the novel genotypes were not related to any other cultivars included in this study. These findings as well as the detection
of unique alleles and a certain wild genetic background at some cultivars revealed by the Bayesian analysis may indicate their
autochthonous origin. The synonymy cases found between local cultivars and Italian mainland cultivars indicate interchange
of genetic material among these growing areas, suggesting thus a possible allochthonous origin. The information obtained can
assist in the management of an olive collection and sheds some light on the survival of true oleasters and the origin of Sardinian
cultivars. 相似文献
183.
Barbosa J Freitas A Mourão JL Noronha da Silveira MI Ramos F 《Journal of agricultural and food chemistry》2012,60(17):4227-4234
The use of nitrofurans as veterinary drugs has been banned from intensive animal production in the European Union (EU) since 1993. The objective of the present study was to evaluate the accumulation and depletion of furaltadone and nifursol and their side-chain metabolites 5-methylmorpholino-3-amino-2-oxazolidinone (AMOZ) and 3,5-dinitrosalicylic acid hydrazide (DNSAH) in eggs after administration of therapeutic and subtherapeutic doses of the drugs to laying hens during three consecutive weeks. LC-MS/MS, with positive and negative electrospray ionization methods, was used for the determination of parent compounds and metabolites in yolk and egg white and was validated according to criteria established by Commission Decision 2002/657/EC. The decision limit (CCα) and the detection capability (CCβ) of the analytical methodology for metabolites were 0.1 and 0.5 μg/kg for AMOZ and 0.3 and 0.9 μg/kg for DNSAH, respectively. For the parent compounds, CCα and CCβ were 0.9 and 2.0 μg/kg for furaltadone and 1.3 and 3.1 μg/kg for nifursol, respectively. The data obtained show that the parent compounds are much less persistent than their side-chain metabolites in either yolk or egg white. Between the studied metabolites, AMOZ is the most persistent and could be detected in either yolk or egg white three weeks following withdrawal from treatment. 相似文献
184.
Alvarez Luis H. Jimenez-Bermudez Laura Hernandez-Montoya Virginia Cervantes Francisco J. 《Water, air, and soil pollution》2012,223(4):1911-1920
Fulvic acids (FA) were immobilized on alumina particles in order to evaluate their catalytic effect as solid-phase redox mediator
(RM) during the reductive dechlorination of carbon tetrachloride (CT) by anaerobic sludge. FA were extracted from three different
soil samples and two commercial composts. Electron carrying capacity (ECC) was determined in all FA samples in order to select
the appropriate source of redox-mediating compounds for CT dechlorination. TiO2, Al(OH)3, and γ-Al2O3 particles were tested as immobilizing materials for the extracted FA. FA extracted from a temperate pine forest soil showed
the highest ECC (291.72 μmol g−1). The highest adsorption capacity of FA, measured as total organic carbon (TOC), was achieved by alumina (γ-Al2O3) particles (12 mg TOC-FA g−1). Results suggest that the transfer of electrons rather than their microbial generation through glucose fermentation was
the rate-limiting factor during dechlorination of CT. Immobilized FA increase up to 10.4-fold the rate of CT dechlorination
as compared with the control lacking FA. Immobilization of FA on alumina particles was very stable, and spectrophotometric
screening did not detect any detachment of FA during dechlorination of CT, thus confirming that the enhanced dechlorination
achieved could exclusively be linked to the redox-mediating capacity of immobilized FA. The present study constitutes the
first demonstration that immobilized FA on alumina particles could serve as a solid-phase RM in dechlorination reactions. 相似文献
185.
Summary Artificial selection in autogamous species is investigated applying standard algebraic techniques to conventional self-pollinating breeding systems as well as to recurrent cross-pollinating ones for both one and two-locus models. More than two loci are considered by means of computer simulations. Allelic and non-allelic genotypic interactions as well as genes with a large effect are considered whenever possible. The overall picture shows a clear superiority of recurrent selection systems over self-pollinating breeding systems when negative linkage disequilibrium is either present or generated as is expected in actual breeding populations. When epistatic interaction enhances the selective advantage of new recombinants the superiority of recurrent selection is even greater. 相似文献
186.
Luis H. Alvarez Yair A. Del Angel Bernardo García-Reyes 《Water, air, and soil pollution》2017,228(1):38
The aim of this study was to evaluate the redox mediating capacity of anthraquinone-2,6-disulfonate (AQDS) immobilized on granular activated carbon (GAC) during the reductive decolorization of direct blue 71 (DB71) under microbial and chemical conditions. The immobilization of AQDS on GAC was conducted by adsorption, and it has obtained an uptake capacity of 0.227 mmol g?1. The anchorage of AQDS on GAC improved its electron transfer capacity (ETC) up to 2.05 times higher than the raw material. Similarly, the addition of GAC-AQDS increased up to 1.75- and 1.16-fold the rate of decolorization (k d ) of DB71 under microbial and chemical conditions, respectively, in comparison to the unmodified GAC. Surprisingly, a higher k d value was achieved in incubations without either GAC or GAC-AQDS because of the generation of aromatic amines, from the reduction DB71, taking into account that these species may act as a catalyst in the DB71 reduction process. In contrast, adsorption of aromatic amines on either GAC or GAC-AQDS decreased its redox mediating capacity as evidenced by spectrophotometric screenings of the decolorized solution and the supporting material. The development of materials with enhanced both redox and adsorption properties, as the GAC used in this study, offers a promising way to increase the redox conversion of recalcitrant pollutants commonly found in industrial wastewaters. 相似文献
187.
Luis A. Castillo-Suárez Francisco Bruno-Severo Violeta Lugo-Lugo Mario Esparza-Soto Verónica Martínez-Miranda Ivonne Linares-Hernández 《Water, air, and soil pollution》2018,229(12):385
Leachates, particularly those from mature landfills, are difficult to treat by biological processes because of their high toxicity and low biodegradability. Therefore, the development of new treatment technology is necessary. The treatment of landfill leachate by peroxicoagulation and solar peroxicoagulation using a batch electrolytic reactor with a Fe cathode and a Cu anode is proposed. The tested operational variables included pH (2.8 and 8.2), current density (11 and 16 mA cm?2), treatment time (5, 10, 15, 20, 25, and 30 min), and presence of solar ultraviolet (UV) light and were collected using a compound parabolic collector. The optimum conditions were a pH, current density, and treatment time of 2.8, 16 mA cm?2, and 10 min, respectively. The presence of UV did not have a significant effect. The chemical oxygen demand and biochemical oxygen demand removed were 62.3% and 55.5%, respectively. The results of UV-visible absorption, fluorescence, and Fourier transform infrared spectroscopy measurements confirm the oxidation process. 相似文献
188.
Claudio Ezequiel Canul-Tun Luis A. Valdez-Aguilar A. Javier Lozano-del Río Antonio Cárdenas-Flores Alejandro Zermeño-González 《Journal of plant nutrition》2017,40(8):1083-1090
The aim of this study was to determine if plastic mulch films may have positive effects on bell pepper plants grown under shade house conditions. The experimental design was split-plot, where large plots contained four plastic mulch films (black, aluminum, silver, and white) compared to bare soil and small plots contained two bell pepper cultivars. Plant shoot dry weight was higher in plastic mulch treatments than in bare soil. The net photosynthesis rate in the cultivar SWG-46 exceeded in net photosynthesis with respect to the cultivar SWG-42 in one of three sampling dates. Nutrients in leaf showed a similar behavior in plastic mulch treatments than the control but the total content of nitrogen (N), potassium (K), and sulfur (S) was increased. The total yield was higher in black plastic mulch than in the other plastic mulch colors and lowest in the control. 相似文献
189.
Ortega Jaime Díaz Sedov Sergey Romero Francisco Jardines Luis Gerardo Martínez Rebolledo Elizabeth Solleiro 《Journal of Soils and Sediments》2022,22(3):942-956
Journal of Soils and Sediments - The objective of this study was to examine the pedogenetic evolution occurring in technic hard materials from an iron mine through the characterization of a... 相似文献
190.
Luis Miguel Brito Áurea Sampaio Rui Pinto Isabel Mourão João Coutinho 《Journal of plant nutrition》2016,39(6):842-849
The response of lettuce to production system, organic and phosphate fertilizers and root mycorrhization, was evaluated in two pot trials with factorial treatment combination of: (i) soil type (from organic and from conventional production systems) and organic fertilizer (0, 2 and 4 t ha?1) in the first trial; and (ii) mycorrhizal inoculation (mycorrhized and non-mycorrhized plants) and Gafsa phosphate (0, 100 and 200 kg P2O5 ha?1) in the second. Lettuce growth decreased with increasing rates of the organic fertilizer because of its very high electrical conductivity (50.1 dS m?1) and lack of maturation. However, the fertilizer harmful effects were minimized in the soil from organic production. The application of Gafsa phosphate significantly increased lettuce yield and nutrient uptake. However, for the highest rate of phosphate, mycorrhized lettuce yield decreased compared to non-mycorrhized lettuce, suggesting that high soil available P may have harmful effects on the activity of mycorrhizal fungi. 相似文献