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91.
Svetaz L Tapia A López SN Furlán RL Petenatti E Pioli R Schmeda-Hirschmann G Zacchino SA 《Journal of agricultural and food chemistry》2004,52(11):3297-3300
The crude methanolic extract of Zuccagnia punctata was active toward the fungal pathogens of soybean Phomopsis longicolla and Colletotrichum truncatum. Assay guided fractionation led to the isolation of two chalcones, one flavanone and a new caffeoyl ester derivative as the compounds responsible for the antifungal activity. Another new caffeoyl ester derivative was isolated from the antifungal chloroform extract but proved to be inactive against the soybean infecting fungi up to 50 microg/mL 相似文献
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95.
Corella-Madueño MA Harris MK Fu-Castillo AA Martínez-Téllez MA Valenzuela-Soto EM Gálvez-Ruiz JC Vargas-Arispuro I 《Pest management science》2011,67(12):1522-1527
BACKGROUND: Plant volatiles have complex intra‐ and interspecific effects in the environment that include plant/herbivore interactions. Identifying the quantity and quality of volatiles produced by a plant is needed to aid the process of determining which chemicals are exerting what effects and then examining whether these effects can be manipulated to benefit society. The qualitative characterization of volatile compounds emitted by pecan, Carya illinoinensis (Wang.) K. Koch, was begun in order to establish a database for investigating how these volatiles affect Acrobasis nuxvorella Nuenzig, a monophagous pest of pecan. Headspace solid‐phase microextraction combined with gas chromatography–mass spectrometry was used for the analysis of the volatile constituents of pecan during three phenological stages (dormant buds, intact new shoot growth and intact nutlets) of the Western Schley and Wichita cultivars. RESULTS: About 111 distinct compounds were identified from the two cultivars, accounting for ～99% of the headspace volatiles. The chromatographic profiles of both varieties revealed variations in the volatile composition and proportion between cultivars, with a predominance of terpene hydrocarbons, of the sesquiterpenes class, as well as monoterpenes. CONCLUSION: The significantly higher responsiveness recorded for the larvae of A. nuxvorella to C. illinoinensis shoots indicates that the larvae may be activated by terpenes emanating from the new shoot growth. This is the first study that has examined volatiles of pecan in Mexico. Copyright © 2011 Society of Chemical Industry 相似文献
96.
Manoj Kumar Mishra Patrizia Tornincasa Barbara De Nardi Elisa Asquini René Dreos Lorenzo Del Terra Rajkumar Rathinavelu Paola Rovelli Alberto Pallavicini Giorgio Graziosi 《Journal of Crop Science and Biotechnology》2011,14(1):25-37
An EST-based PCR-RFLP method was employed to gain insight into genome organization in eight allopolyploid Coffea arabica cultivars and seven diploid coffee species. The PCR-amplified products at 19 EST loci were digested with 46 different restriction
enzymes and size fractioned in agarose gels. Most often, the sum of the fragments length was double or more than the PCR product.
In arabica, this condition could be explained by assuming the presence of duplicated loci in paralogous chromosomes and this
was supported by considerable evidence of multiple loci SSR amplification. Based on the RFLP analysis, 12 EST loci were polymorphic.
The level of polymorphism was higher in different species compared to the arabica varieties. Sequencing of the amplified products
revealed a SNP frequency of 0.021 among diploid species and of 0.007 among arabica varieties. We propose that the involvement
of two genomes in C. arabica maintains a residual level of heterozygosity in the form of paralogous chromosomes, while the self-fertilization in this
species tends to drive of homozygosity. The heterozygosity of paralogous chromosomes in arabica creates valuable polymorphism
essential for species diversity and survival in various ecological niches, while self-fertility tends to preserve in homozygosity
many genes of functional significance. 相似文献
97.
M��nica Patr��n-Prado Margarita Casas-Valdez Elisa Serviere-Zaragoza Tania Zenteno-Sav��n Daniel B. Lluch-Cota L��a M��ndez-Rodr��guez 《Water, air, and soil pollution》2011,221(1-4):137-144
Brown algae Sargassum sinicola and Sargassum lapazeanum were tested as cadmium biosorbents in coastal environments close to natural and enriched areas of phosphorite ore. Differences in the concentration of cadmium in these brown algae were found, reflecting the bioavailability of the metal ion in seawater at several sites. In the laboratory, maximum biosorption capacity (q max) of cadmium by these nonliving algae was determined according to the Langmuir adsorption isotherm as 62.42?±?0.44 mg g?1 with the affinity constant (b) of 0.09 and 71.20?±?0.80 with b of 0.03 for S. sinicola and S. lapazeanum, respectively. Alginate yield was 19.16?±?1.52% and 12.7?±?1.31%, respectively. Although S. sinicola had far lower biosorption capacity than S. lapazeanum, the affinity for cadmium for S. sinicola makes this alga more suitable as a biosorbent because of its high q max and large biomass on the eastern coast of the Baja California Peninsula. Sargassum biomass was estimated at 180,000 t, with S. sinicola contributing to over 70%. 相似文献
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Lozano-Sánchez J Giambanelli E Quirantes-Piné R Cerretani L Bendini A Segura-Carretero A Fernández-Gutiérrez A 《Journal of agricultural and food chemistry》2011,59(21):11491-11500
Phenolic compounds in extra virgin olive oil (EVOO) have been associated with beneficial effects for health. Indeed, these compounds exert strong antiproliferative effects on many pathological processes, which has stimulated chemical characterization of the large quantities of wastes generated during olive oil production. In this investigation, the potential of byproducts generated during storage of EVOO as a natural source of antioxidant compounds has been evaluated using solid-liquid and liquid-liquid extraction processes followed by rapid resolution liquid chromatography (RRLC) coupled to electrospray time-of-flight and ion trap mass spectrometry (TOF/IT-MS). These wastes contain polyphenols belonging to different classes such as phenolic acids and alcohols, secoiridoids, lignans, and flavones. The relationship between phenolic and derived compounds has been tentatively established on the basis of proposed degradation pathways. Finally, qualitative and quantitative characterizations of solid and aqueous wastes suggest that these byproducts can be considered an important natural source of phenolic compounds, mainly hydroxytyrosol, tyrosol, decarboxymethyl oleuropein aglycone, and luteolin, which, after suitable purification, could be used as food antioxidants or as ingredients in nutraceutical products due to their interesting technological and pharmaceutical properties. 相似文献
100.
Elisa M. Mazzaferro MS DVM Elke Rudloff DVM DACVECC Rebecca Kirby DVM DACVIM DACVECC 《Journal of Veterinary Emergency and Critical Care》2002,12(2):113-124
Objective: To review the human and veterinary literature on the physiological role and effects of therapeutic albumin supplementation. Data sources: Data from human and veterinary literature was reviewed. Human data synthesis: Hypoalbuminemia often occurs in a variety of critical illnesses, and contributes to the development of life‐threatening complications, including pulmonary edema, delayed wound healing, feeding intolerance, hypercoaguability, and multiple organ dysfunction. Serum albumin concentration has been used as a prognostic indicator in cases of chronic hypoalbuminemia. The use of albumin replacement therapy in humans is sometimes controversial, but may be associated with improved morbidity and decreased mortality. Veterinary data synthesis: Unlike human literature, there is a paucity of controlled clinical studies in the literature regarding albumin supplementation in veterinary patients. Rather, the majority of published studies were performed in experimental animals or via retrospective analyses. One recent study evaluated the use of plasma to improve albumin concentration in dogs with hypoalbuminemia. Other older studies investigated wound healing in dogs with experimentally induced hypoalbuminemia. As in human medicine, serum albumin concentration may be helpful as a prognostic indicator in critically ill dogs. Conclusion: Albumin is one of the most important proteins in the body because of its role in maintenance of colloid oncotic pressure, substrate transport, buffering capacity, as a mediator of coagulation and wound healing, and free‐radical scavenging. Albumin replacement in veterinary medicine is difficult, but until prospective clinical trials determine the efficacy of albumin replacement are conducted, a suggested clinical guideline would be to maintain albumin concentration at or above 2.0 g/dl utilizing fresh frozen plasma. 相似文献