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101.
Qualitative and quantitative analyses of betalain pigments in 10 cultivars/lines of prickly pear (Opuntia spp.) fruit grown in Mexico were conducted with reverse phase high-performance liquid chromatography-diode array detection (HPLC-DAD) coupled with electrospray mass spectrometry (ESI-MS). Betacyanins and betaxanthins were identified by comparison with the UV/vis and mass spectrometric characteristics as well as the retention times of semisynthesized reference betaxanthins. Data revealed that the ratio and concentration of betalain pigments are responsible for the color in the different cultivars, showing the highest betalains content in the fruit of purple colored Camuesa (O. robusta Wendl.) (8.1 mg/g dry fruit), which is comparable to that found in red beet Beta vulgaris L. ssp. Var. Pablo) (8.6 mg/g dry tissue). Yellow betalains were absent in Reyna (O. alba-carpa) prickly pear cultivar. A total of 24 known/unknown betalains were present in the prickly pear fruit samples studied, including 18 betaxanthins and 6 betacyanins. Our results indicate that prickly pear cultivars can be considered as a potential source of yellow and red natural colorants. 相似文献
102.
Cequier-Sánchez E Rodríguez C Ravelo AG Zárate R 《Journal of agricultural and food chemistry》2008,56(12):4297-4303
The usefulness of the solvent mixture dichloromethane/methanol for lipid extraction and the determination of lipid classes and fatty acids in samples of different natures was conducted. Two different extraction methods were compared, one containing chloroform/methanol, another containing dichloromethane/methanol. Total lipid extraction showed some minor differences but no variation in the lipid classes. Regarding the fatty acid profile, in Echium virescens seeds, 17 major fatty acids could be identified and quantified, and all were equally extracted when either solvent system was employed. In Echium acanthocarpum hairy roots, 17 major fatty acids were quantified, showing some statistical differences for one cell line in favor of chloroform. The data obtained from the liquid nutrient medium were also comparable. The cod roe sample showed 31 major fatty acids, showing no statistical differences between the two solvent systems. Contrarily, the CH 2Cl 2 method was able to extract 31 main fatty acids found in European seabass dorsal muscle more efficiently than the CHCl 3 method. The results indicate that, for lipid extraction and fatty acid assessment, dichloromethane/methanol can readily replace the commonly employed chloroform/methanol, thus avoiding the major health, security, and regulatory problems associated with the use of chloroform. 相似文献
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Attilio L. Mordenti Nico Brogna Giorgia Canestrari Elena Bonfante Stefano Eusebi Ludovica M. E. Mammi Elisa Giaretta Andrea Formigoni 《Animal Science Journal》2019,90(5):619-627
Focus of this study was to evaluate the most suitable breed/crossbred and the appropriate nutritional strategies to increase marbling in beef muscle and to improve its healthy properties, in particular the n‐3 fatty acids content. One hundred and seventy‐six heifers of three crossbreed commonly reared by Emilia‐Romagna farmers: 48 Bleu Belge × Freisian (ITA), 48 Charolais × Aubrac (FRA), and 80 Angus (ANG) were used. Animals of each breed were randomly subdivided in two experimental groups that received two diets, differing for the dietary lipid source. Control group (C) received a basal diet containing protected vegetable fats, whereas treated one (T) received the same basal diet supplemented with 0.9 kg/head/day of extruded flaxseed. After slaughtering, a sample of Longissimus thoracis was collected from each animal for meat quality analysis. Our results demonstrated that, in a shorter fattening period, ANG animals obtained the best dry matter intake, average daily gain and the best fattening scores. ITA and ANG meat presented the highest marbling scores. ANG breed had the highest amount of C18:1, the highest unsaturated/saturated fatty acids ratio and the lowest n‐6/n‐3 ratio. The T animals, independently from breed, showed the highest amount of α‐linolenic acid (ALA). In addition, ANG‐T meat presented the highest ALA content. 相似文献
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A severe crown rot of pear trees of cultivar ‘Kondoula’ grafted on quince rootstock was observed in Greece. Isolations from
the affected tissues repeatadly yielded aPhytophthora sp. that was determined by morphological and physiological characteristics to beP. citrophthora. The pathogenicity of two of theP. citrophthora isolates was tested by inoculating trunks of 2-year-old pear trees by mycelial agar disks. Thirty-two days after inoculation
all inoculated trees were infected. Although the pear isolates could not be differentiated from isolates ofP. palmivora orP. nicotianae based on isozyme profiles of α-esterase or lactate dehydrogenase, RAPD profiles with one selected primer differentiated the
pear isolates from the other species and revealed an electrophoretic banding pattern similar to that of aP. citrophthora standard. This is the first report ofP. citrophthora on pear trees in Greece. 相似文献
109.
Robles Esperanza Ramírez Pedro Elena González Ma. de Guadalupe Sáinz Ma. Martínez Blanca Durán Angel Elena Martínez Ma. 《Water, air, and soil pollution》1999,113(1-4):217-226
Bacteriological and physico-chemical parameters of 265 samples from 39 brands sold in 5-gallon plastic and glass bottles and 2-5 L plastic containers were analyzed to determine the quality of bottled water distributed in Mexico City. Tests included fecal and total coliform counts, alkalinity, total hardness, chloride, calcium and magnesium concentrations, pH and conductivity. Correlation and cluster analyses and ANOVA were carried out, and a comparison made of the averages with the maximum permissible levels established in the Official Mexican Norms. Concerning the investigated parameters no differences (p > 0.05) between the brands were found. Physico-chemical parameters were studied and all the samples were within the permissible limits. Most samples taken from the 5-gallon containers exceeded the maximum bacteriological limits. It was concluded that the bacteriological quality of the brands studied was extremely variable. Appropriate sanitary measures, should be established to control this aspect. 相似文献
110.
Donatella Lotti DVM PhD Maria Tresa Capucchio DVM Elena Gaidolfi DM Monica Merlo DVM 《Veterinary radiology & ultrasound》1999,40(6):622-626
A 5-year-old, male Yorkshire Terrier had chronic and progressive neurologic signs compatible with lesions in the right brain stem and right forebrain. In magnetic resonance images of the brain there were multifocal lesions at different stages of evolution, consistent with an inflammatory disease. The lesions were located in the white matter of the cerebrum, in the diencephalon and mesencephalon. These lesions were hypointense in T1-weighted images and hyperintense in T2-weighted images with no mass effect and minimal enhancement with gadolinium. Necrotizing encephalitis was confirmed post mortem. 相似文献