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971.
C. Salinas-Hernández M. C. Díaz-Nava M. Solache-Ríos 《Water, air, and soil pollution》2012,223(8):4959-4968
The capacity of an iron-modified zeolite was evaluated for the removal of two dyes (red 5 and yellow 6) use in foodstuff; the regeneration of the dye-saturated materials was also considered. The zeolitic material (clynoptilolite type) was treated with sodium chloride (Na-Ze) and then with ferric chloride (Fe-Ze). The sorption kinetics and isotherms were evaluated, considering the effect of pH on the sorption processes. Sorption?Cregeneration cycles using iron-modified zeolitic material were performed. The sorption kinetics showed that the sodium-modified zeolitic material removed neither red 5 nor yellow 6 dyes, while the iron-modified zeolitic material removed both dyes; the equilibrium time was reached in 48?h for yellow 6, and it was almost reached in the same time for red 5, the removal percentage for red 5 was 89.4?% and for yellow 6 was 96.7?%. The experimental data showed best adjustment to the pseudo-first-order model (Lagergren), which is based on a superficial reaction. The sorption capacities obtained by the sorption isotherms were 1.6 and 1.7?mg/g for red 5 and yellow 6, respectively. The experimental data were best adjusted to the Langmuir?CFreundlich model which indicates that the sorption takes place on a heterogeneous material. It was also observed that the sorption capacities increase as the pH decreases. The results on the desorption processes showed that the best regenerator agent was Fenton??s reagent; the capacities increased in each sorption?Cregeneration cycle using this reagent; for the red 5, the sorption percentage was 73.6?% in the first cycle and 96.3?% in the third cycle and for yellow 6, the removal percentage was 66.7?% in the first cycle and 80.5?% in the second. 相似文献
972.
Bernabéu JA Torres-Suárez AI Gil-Alegre ME Camacho MA 《Journal of agricultural and food chemistry》2000,48(12):5969-5974
The objective of this paper was to study the stability of a medicated premix and a medicated farm feed containing sulfadimidine as the active ingredient. The medicated premix is supplied as powdered form and administered orally after mixing with animal feed. The sulfadimidine analytical method described in United States Pharmacopoeia 23 cannot be used to carry out the stability study because of its lack of specificity for different degradation products. Therefore, a high-performance liquid chromatography method was developed to assay sulfadimidine. This method was optimized and validated for the stability study. According to International Committee Harmonization (ICH) guidelines, the samples were stored under long-term testing and accelerated conditions for the stability study of the premix and the medicated farm feed. Sulfadimidine degradation was not detected in either form under any of the conditions studied. 相似文献
973.
The carotenoid composition of sarsaparilla ( Smilax aspera L.) berries has been analyzed for the first time. Lycopene was found to be the main carotenoid (242.44 μg/g fresh wt) in the pulp, followed by β-carotene (65.76 μg/g fresh wt) and β-cryptoxanthin (42.14 μg/g fresh wt; including the free and esterified forms). Other minor carotenoids were lycophyll (13.70 μg/g fresh wt), zeaxanthin (8.56 μg/g fresh wt; including the free and esterified forms), lutein (0.94 μg/g fresh wt), and antheraxanthin (0.58 μg/g fresh wt). β-Cryptoxanthin and zeaxanthin were present in free and esterified forms. β-Cryptoxanthin was mainly esterified with saturated fatty acids (capric, lauric, myristic, palmitic, and stearic), although a low amount of β-cryptoxanthin oleate was also detected. In the case of zeaxanthin, only a monoester with myristic acid (zeaxanthin monomyristate) was identified. The diverse carotenoid profile, some with provitamin A activity, together with the relatively high content, up to 375 μg/g fresh wt, makes sarsaparilla berries a potential source of carotenoids for the food, animal feed, and pharmaceutical industries. 相似文献
974.
A Clemente J Vioque R Sanchez-Vioque J Pedroche F Millán 《Journal of agricultural and food chemistry》1999,47(9):3776-3781
Chickpea protein isolate was used as starting material for the production of hypoallergenic protein hydrolysates. Western blotting of the protein isolate showed that IgE in sensitized patient sera strongly bound to the basic polypeptidic chains and recognized the acidic ones of 11S globulin. During the hydrolysis process by the individual and/or sequential action of endo- and exoproteases, a high reduction of antigenic activity was observed. Results suggest that the presence of intact or partially hydrolyzed basic polypeptide chains of 11S globulin are responsible for the formation of IgE complexes in protein hydrolysates obtained by exoprotease treatment; however, the digestion of these polypeptide chains by individual action of endoprotease caused a high loss of antigenic activity. The most effective reduction of antigenicity, >90%, was observed in extensive hydrolyzed chickpea proteins obtained by sequential treatment with endo- and exopeptidases. This chickpea protein hydrolysate could be useful for the elaboration of specialized hypoallergenic food products. 相似文献
975.
Dapeng Zhang Jim Cervantes Zosimo Huamán Edward Carey Marc Ghislain 《Genetic Resources and Crop Evolution》2000,47(6):659-665
The sweet potato genebank at the International Potato Center (CIP) maintains 5,526 cultivated I. batatas accessions from 57 countries. Knowledge of the genetic structure in this collection is essential for rational germplasm conservation and utilization. Sixty-nine sweet potato cultivars from 4 geographical regions (including 13 countries) of Latin America were randomly sampled and fingerprinted using AFLP markers. A total of 210 polymorphic and clearly scorable fragments were generated. A geographic pattern of diversity distribution was revealed by mean similarity, multidimensional scaling (MDS), and analysis of molecular variance (AMOVA). The highest genetic diversity was found in Central America, whereas the lowest was in Peru-Ecuador. The within-region variation was the major source of molecular variance. The between-regions variation, although it only explains 10.0% of the total diversity, is statistically significant. Cultivars from Peru-Ecuador, with the lowest level of within region diversity, made the most significant contribution to the between region differentiation. These results support the hypothesis that Central America is the primary center of diversity and most likely the center of origin of sweet potato. Peru-Ecuador should be considered as a secondary center of sweet potato diversity. 相似文献
976.
C. Guzmán L. Caballero A. Moral J. B. Alvarez 《Genetic Resources and Crop Evolution》2010,57(5):721-725
Spelt wheat is a neglected crop that could be used in the quality breeding of modern common wheat. One important aspect of
this quality is the starch composition which is related to the waxy proteins. A collection of 420 accessions of Spanish spelt
wheat was analysed for waxy protein composition by SDS–PAGE. Polymorphism was found in the three waxy proteins, detecting differences both in size and in activity, and a new waxy allele (Wx-D1g) was identified. Seed amylose content was also determined and significant differences were detected among the different allelic combinations.
In general, the accessions carrying one or two waxy null alleles showed less amylose content. The variation found could be used to enlarge the genetic pool of common wheat,
or to develop lines of spelt with different levels of amylose content. 相似文献
977.
Alex Beharav Roi Ben-David Ivana Doležalová Aleš Lebeda 《Genetic Resources and Crop Evolution》2010,57(5):679-686
The wild lettuce, Lactuca aculeata Boiss. et Ky., is closely related and fully interfertile with cultivated lettuce, Lactuca sativa L. Altogether, 155 accessions of this wild species, which is rare conserved within the world’s germplasm collections, were
collected from 12 localities throughout northeastern Israel. Ten of these localities represent different sites across the
Golan Heights, while two, high-density populations were suprisingly found at the Hula Plain (first report of this species
in this region). Lactuca aculeata was recorded at various elevations (222–968 m a.s.l.) and habitats. The taxonomic status of 30 L. aculeata accessions was morphologically validated during ex situ seed regeneration of 31 random accessions representing all 12 localities. Characterization of 12 traits showed that the Israeli
populations of L. aculeata do not exhibit broad morphological variability, but more great levels of variation were obtained for developmental traits.
Relatively little variability was observed in the morphology of cauline leaves or in the distribution of anthocyanin pigmentation
in bracteae. In two cases, L. aculeata plants lacked trichomes in the inflorescence, a typical feature in the majority of plants. These unique collections of wild
lettuce may carry novel sources of genetic variation for a wide range of traits and, thus, should be of interest for careful
evaluation and exploitation in lettuce breeding. 相似文献
978.
The characterization of plant genetic resources is the first step towards improving their use. The Spanish Plant Genetic Resources
Centre, which belongs to the National Institute for Agricultural and Food Technology Research (CRF-INIA), conserves accessions
of wild underground vetches collected in Spain. In the present work, 26 underground vetch accessions were characterized in
terms of their seed storage proteins (separated by SDS-PAGE) as a means of assessing the genetic variation of these plants
and their agronomic value. Vicia sativa cv. Vereda was used as control. A total of 54 bands were detected, of which 49 were polymorphic. Fifty eight different electrophoretic
patterns were observed in total. Protein bands were scored in terms of their presence (1) or absence (0) for all the seeds
studied, and two matrices constructed, one with all the bands present in each accession, the other with the different patterns
for each accession. Dendrograms based on the Jaccard similarity index and the UPGMA clustering method were produced from these
matrices, and the degree of genetic variation between and within accessions was calculated. The groups obtained were compared
with the chromosome number for each accession. The results reflect the great diversity of underground vetch seed storage proteins.
The aerial and underground seeds of 16 accessions were then analysed separately. In some cases, the aerial and underground
flowers of the same plant produced different proteins. 相似文献
979.
López-Valdivia LM Fernández MD Obrador A Alvarez JM 《Journal of agricultural and food chemistry》2002,50(6):1455-1460
Experiments under laboratory and greenhouse conditions were conducted to study the response of maize (Zea mays L.) to Zn fertilizer applications (Zn-phenolate, Zn-EDDHA, Zn-EDTA, Zn-lignosulfonate, Zn-polyflavonoid, and Zn-heptagluconate) in an Aquic Haploxeralf soil. The application of Zn complexes significantly increased Zn uptake by the plant compared with that in the control soil. The highest enhancements were obtained in soil treated with Zn-EDTA, Zn-lignosulfonate, and Zn-EDDHA. The highest percentages of Zn taken up by the plants occurred when 20 mg x kg(-1) Zn was applied as Zn-EDTA fertilizer and 10 mg x kg(-1) as Zn-lignosulfonate fertilizer. In the greenhouse experiment, Zn speciation in soil after harvesting showed that almost all Zn was found in the residual fraction followed by metal in the water-soluble plus exchangeable fraction and metal bound to organic matter. The most effective fertilizers maintaining Zn in the most labile fractions were Zn-phenolate, Zn-EDTA, and Zn-lignosulfonate. Conversely, in the incubation experiment, only a small percentage of Zn was found in the water-soluble plus exchangeable fraction and no differences in the Zn distribution were observed between the different fertilizer treatments. The micronutrient content in maize was positively correlated with the water-soluble plus exchangeable Zn as well as with the available Zn determined by the diethylenetriaminepentaacetic acid and Mehlich-3 methods, in the greenhouse experiment. Results of this study showed that the incubation experiment in acidic soil is not a suitable tool to establish the different effectiveness of Zn chelates in plants. 相似文献
980.
Hernán Laurentin 《Genetic Resources and Crop Evolution》2009,56(2):277-292
Characterizations of plant genetic resources based on molecular markers have been increased in the last years. Studies using
a broad range of markers applied on hundreds of plant species are the theoretical basis for inferring genetic diversity to
propose both breeding and conservation strategies. Despite increased importance of molecular characterization in plant genetic
resources, there is scarce information about analysis of this type of data. To fill this gap of information, this review discuss
the rationale behind analyses achieved to study genetic relationship among accessions (within and between groups) and to identify
accession, and also discuss the adequacy of some analyses and/or parameters for specific purposes. Genetic diversity within
groups may be either quantified for the whole group (parameters to choose will depend on type of marker), or quantified and
visualized for the relationships among individuals. Quantification parameters will be chosen depending on type of marker,
reproduction mode and relatedness of individuals. Visualization is achieved by hierarchical and non-hierarchical methods.
Genetic diversity between groups should be quantified either by analysis of molecular variance, or Nei’s parameters, or Wright’s
F-statistics. Efficiency of accession identification can be evaluated by maximal probability of identical match by chance
and number of resolved genotypes. 相似文献