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101.
Maria Isabel Abdo‐de la Parra Armando García‐Ortega Irma Martínez‐Rodríguez Blanca González‐Rodríguez Gabriela Velasco‐Blanco Crisantema Hernández Neil Duncan 《Aquaculture Research》2010,41(10):e554-e560
In this study bullseye puffer, Sphoeroides annulatus larvae were reared from hatching through to 1 or 2 months after weaning on an experimental scale in three replicate 600 L tanks and on three occasions during the spawning season (nine tanks in total). The rearing protocol used was green water (Nannochloropsis oculata and Isochrysis sp.) 100 000 cells mL?1 from 0 to 11 days after hatch (DAH), 5–10 rotifers, Brachionus rotundiformis mL?1 from 2 to 26 DAH, 0.1–1 Artemia mL?1 from 21 to 34 DAH and weaning from 29 to 34 DAH. Survival to a month after weaning was 1%, a total of 3153 juveniles were produced with an average wet weight of 0.29 ± 0.07 g and a length of 27.5 ± 0.82 mm. 相似文献
102.
J Velasco 《Journal of the Association of Official Analytical Chemists》1975,58(4):757-763
Filter fluorometers have been adapted to measure the fluorescence intensity of aflatoxin absorbed on a Florisil layer in minicolumns. The relationship between concentration and intensity is near linear in the aflatoxin range from 10 to 100 ng. Although individual aflatoxin fractions cannot be resolved, since the measure is one of total intensity, fluorometric measurements advance the minicolumn screening procedure to a semiquantitative level. The detection of 1 ng aflatoxin B1 is well within the limits of a filter fluorometer with a photomultiplier detector. A precision, expressed as per cent coefficient of variation, ranging from 1.2 to 4.2%, was obtained for standard B1 columns. 相似文献
103.
Mallikarjuna K. Aradhya Dianne Velasco Ji‐Rui Wang Ramesh Ramasamy Frank M. You Chuck Leslie Abhaya Dandekar Ming‐Cheng Luo Jan Dvorak 《Plant Breeding》2019,138(5):635-646
A genetic linkage map of walnut containing 2,220 single nucleotide polymorphisms (SNPs) in 16 linkage groups (LGs) was constructed using an F1 mapping population from a cross between “Chandler” and “Idaho,” two contrasting heterozygous parents. Five quantitative yield traits, lateral fruitfulness, harvest date and three nut traits (shell thickness, nut weight and kernel fill) were then mapped on to linkage groups. A significant quantitative trait locus (QTL) in LG 11 with negative additive effects suggested heterozygote superiority in the expression of lateral bearing. A set of three QTLs explaining ~10% of the variation in harvest date was located in LG 1. Shell thickness, nut weight and kernel fill were under the control of two to three linked pleiotropic QTLs in LG 1 segregating from “Idaho.” The marginal positive additive effects of QTLs for harvest date, shell thickness and nut weight and small negative additive effects for kernel fill suggested that the QTLs had a marginal effect on the expression of these traits. 相似文献
104.
Velasco P Cartea ME Gonzalez C Vilar M Ordas A 《Journal of agricultural and food chemistry》2007,55(3):955-962
Kales (Brassica oleracea acephala group) are important vegetable crops in traditional farming systems in the Iberian Peninsula. They are grown throughout the year to harvest their leaves and flower buds. The glucosinolate content of kales is dependent upon the environmental factors, plant part examined, phenological stage of plant growth, and level of insect damage. The objectives of this study were to evaluate the changes in the total and individual glucosinolate concentrations during plant development and to determine if significant variation of glucosinolate levels can be explained by insect pests attack and other environmental factors in four locations in northwestern Spain. The total glucosinolate concentration in leaves of B. oleracea increased with plant age from seedling to early flowering stages. At that stage, the aliphatic glucosinolate content in leaves of B. oleracea declined drastically over time as the content in the flower buds increased. The highest contents of indolyl glucosinolate (glucobrassicin) and of the aromatic glucosinolate occurred in leaves harvested at the optimum consumption stage while flower buds contained the highest concentration of aliphatic glucosinolates, especially sinigrin. Sinigrin is reported to have anticarcinogenic properties. There appears to be a loss of total and individual glucosinolate concentrations related to pest attack. Leaves damaged by lepidopterous pests contained a lower total glucosinolate content (25.8 micromol g-1 dw) than undamaged leaves (41 micromol g-1 dw). The amounts of sinigrin, glucoiberin, and glucobrassicin were also lowest in insect-damaged leaves. Environmental factors such as soil properties and temperature appear to influence the glucosinolate content in leaves although more research on this subject is needed. 相似文献
105.
Cytotoxicity of the ascidian Cystodytes dellechiajei against tumor cells and study of the involvement of associated microbiota in the production of cytotoxic compounds 下载免费PDF全文
Martinez-García M Diaz-Valdés M Ramos-Esplá A Salvador N Lopez P Larriba E Antón J 《Marine drugs》2007,5(3):52-70
Many cytotoxic compounds of therapeutic interest have been isolated from marine invertebrates, and some of them have been reported to be of microbial origin. Pyridoacridine alkaloids are the main compounds extracted from the ascidian Cystodytes dellechiajei. Here we describe the in vitro antiproliferative activity against different tumor cell lines of the ascidian extracts and provide some insights on the role of the microbial community associated with the tunicate in the production of these compounds. C. dellechiajei extracts showed remarkably high antiproliferative activity (IC50 ≤5 μg/mL) in human lung carcinoma A-549, colon adenocarcinoma H-116, pancreatic adenocarcinoma PSN-1 and breast carcinoma SKBR3 cell lines. Moreover, we found that the maximum activity was located in the tunic tissue of the colony, which harbours a microbial community. In order to ascertain the involvement of this community in the synthesis of the bioactive compounds different approachs that included culture and culture independent methods were carried out. We undertook a screening for antiproliferative activities of the bacterial isolates from the ascidian, as well as a comprative analysis of the cytotoxic activities and the microbial communities from two color morphs of the ascidian, green and blue. In addition, the changes of the antiproliferative activities and the composition of the microbial communities were studied from ascidians kept in aquaria and treated with antibiotics for one month. Our data obtained from the different experiments did not point out to bacteria as the source of the cytotoxic compounds, suggesting thus an ascidian origin. 相似文献
106.
107.
Margarita Lema María Elena Cartea Tamara Sotelo Pablo Velasco Pilar Soengas 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):159-169
Black rot, caused by Xanthomonas campestris pv. campestris (Xcc) is a severe seedborne disease of Brassica crops around the world. Nine races are recognized, being races 1 and 4 the
most aggressive and widespread. The identification of Xcc races affecting Brassica crops in a target area is necessary to
establish adequate control measures and breeding strategies. The objectives of this study were to isolate and identify Xcc
strains from northwestern Spain by using semi-selective medium and pathogenicity tests, determine the existing races of Xcc
in this area by differential series of Brassica spp., and evaluate the use of repetitive DNA polymerase chain reaction-based fingerprinting (rep-PCR) to differentiate among
the nine existing Xcc races. Seventy five isolates recovered from infected fields were identified as Xcc. Race-typing tests
determined the presence of the following seven pathogen races: 1, 4, 5, 6, 7, 8 and 9. Race 4 was the most frequent in Brassica oleracea and race 6 in Brassica rapa crops, therefore breeding should be focussed in obtaining resistant varieties to both races. Cluster analysis derived from
the combined fingerprints showed four groups, but no clear relationship to race, crop or geographical origin was found. Rep-PCR
analysis was found not to be a reliable method to discriminate among Xcc races, therefore race typing of Xcc isolates should
be done by using the differential series of Brassica spp. genotypes or another alternative approach. 相似文献
108.
Cortadellas O del Palacio MJ Bayón A Soriano AA López JT 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2012,26(2):225; author reply 226
109.
Velasco J Marmesat S Bordeaux O Márquez-Ruiz G Dobarganes C 《Journal of agricultural and food chemistry》2004,52(14):4438-4443
The formation and evolution of monoepoxy fatty acids, arising from oleic and linoleic acids, were investigated in olive oil and conventional sunflower oil, representatives of monounsaturated and polyunsaturated oils, respectively, during thermoxidation at 180 degrees C for 5, 10, and 15 h. Six monoepoxy fatty acids, cis-9,10- and trans-9,10-epoxystearate, arising from oleic acid, and cis-9,10-, trans-9,10-, cis-12,13-, and trans-12,13-epoxyoleate, arising from linoleic acid, were analyzed by gas chromatography after oil derivatization to fatty acid methyl esters. Considerable amounts, ranging from 4.29 to 14.24 mg/g of oil in olive oil and from 5.10 to 9.44 mg/g of oil in sunflower oil, were found after the heating periods assayed. Results showed that the monoepoxides quantitated constituted a major group among the oxidized fatty acid monomers formed at high temperature. For similar levels of degradation, higher contents of the monoepoxides were found in olive oil than in sunflower oil. Ten used frying oils from restaurants and fried-food outlets in Spain were analyzed to determine the contents of the monoepoxides in real frying oil samples. Levels ranged from 3.37 to 14.42 mg/g of oil. Results show that, for similar degradation levels, the monoepoxides were more abundant in the monounsaturated oils than in the polyunsaturated oils. 相似文献
110.
Miyazawa Mário Giminez Sôonia M. N. Yabe Maria Josefa S. Oliveira Edson L. Kamogawa Marcos Y. 《Water, air, and soil pollution》2002,138(1-4):211-222
The interaction between copper, zinc, and chicken manure, whenadded to soil, was studied in a greenhouse setting. Coppersulfate and of zinc chloride at concentrations of 0.5 to 2.0mmol kg-1 were added separately to pots containing 3.0 kgof dystrophic dark red latosoil (LEd) plus 1,0% (m/m) pH 4.2chicken manure. IAPAR 57 beans were used as test plant andcultivated in the experimental soils for 30 days. Plant growthin terms of dry weight and the concentrations of copper and zincin the aerial part of the plants were determined. Bean plantingswere repeated four times, at four-month intervals. A 20%decrease in dry weight was observed when amounts of copper orzinc equal to or geater than 1.0 or 2.0 mmol kg-1, respectively, were applied to the soil over an average of fourplantings. For these concentrations, the average amount of metalfound in the plant was 13.4 mg kg-1 for copper and 224.8 mgkg-1 for zinc. Chlorosis of the leaves in the bean plantswas also observed. The copper and zinc concentrations in thetreated soil were determined using different extractants. Amongthe solutions evaluated for the extraction of available zinc,1.0 M ammonium acetate, pH 4.8, showed a better correlation withthe metal concentration in the plant. As for copper, the bestcorrelation was found with the Mehlich-1 extractant. 相似文献