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991.
Solid phase extraction and liquid chromatography-tandem mass spectrometry for the evaluation of 4-hydroxy-2-nonenal in pork products 总被引:2,自引:0,他引:2
Zanardi E Jagersma CG Ghidini S Chizzolini R 《Journal of agricultural and food chemistry》2002,50(19):5268-5272
This research was aimed at setting up an analytical method for the determination in pork products of 4-hydroxy-2-nonenal (4-HNE), an aldehyde produced from the oxidation of omega-6-polyunsaturated fatty acids. Such a compound mediates various biological effects, but it is considered to be very toxic to mammalian cells at levels higher than physiological ones. The methods used for the determination of 4-HNE in biological fluids, such as blood, were found to be unsuitable for meat samples because both the repeatability and the recovery in spiked samples were unsatisfactory. A new method, based on solid phase extraction and HPLC-MS/MS, was therefore developed and validated. The limit of detection of 4-HNE in spiked samples was 0.043 mg/kg, and the recovery was approximately 60% depending on the concentration. Good linearity was observed in the range of 0.1-10 mg/kg, and repeatability and interday and intraday precision expressed as relative standard deviation were <10%. The method has been successfully applied to the determination of the aldehyde in samples of various pork products. 4-HNE was present in some products, especially the smoked and/or cooked ones, at levels that might not be a real risk for human health. 相似文献
992.
The ornamental industry's difficulties in producing compact and well branched plants have been the subject of extensive evaluation, the problems being compounded by the fact that each species, and even each cultivar, requires a specific protocol. In this work, growth regulators (daminozide, paclobutrazol and chlormequat chloride) and chemical pinching agents (fatty acids) were applied to reduce shoot extension with a view to lowering production costs whilst optimizing plant quality in the production of azalea japonica. Assessment of the effectiveness of the different treatments was achieved using image analysis as a quantitative method which we consider to be a faster and more objective technique than classic biometry. The results indicate that daminozide and paclobutrazol treatment are the best options to control vegetative development and to promote the flowering of azalea japonica in a cold and humid zone such as Asturias. However, daminozide treatment induces floral deformation in one of the tested cultivars, Blaauw's Pink. 相似文献
993.
Colour, shape and size of whole seeds and their spots of some Italian landraces of bean (Phaseolus vulgaris L.) were measured using a specifically developed macro, based on image analysis library KS-400 V 3.0 (Carl Zeiss, Germany). 相似文献
994.
Gnocchi Davide Cesari Gianluigi Calabrese Generosa Jenny Capone Roberto Sabbà Carlo Mazzocca Antonio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(1):33-40
Plant Foods for Human Nutrition - Nowadays, a growing body of evidence supports the view that plants offer an extraordinary opportunity to discover and develop new promising therapeutic strategies... 相似文献
995.
996.
Agricultural practices exert selective forces on weed populations. As these practices change over time, weed adaptive traits also evolve, allowing weeds to persist in the new environment. However, only weeds having individuals showing the trait with adaptive significance will be able to cope with these changes, thus allowing a sub‐population to be selected for persistence. In addition, changes in agricultural practices can select new weed species showing functional traits with characteristics adaptive to the modified system. Seed dormancy has long been recognized as a trait with enormous adaptive value to adjust weed biology to cropping systems. In this paper, we illustrate with examples of success and failure, the value of seed dormancy as a functional trait to cope with long‐term changes in crop production systems. We show that successful outcomes are mostly related to the existence of sufficient variability for the functioning of physiological mechanisms that control dormancy characteristics as influenced by the agricultural environment. Presented examples illustrate how knowledge about the relationship that exists between agricultural practices and their selective pressure on seed dormancy can be instrumental in predicting changes in weed biotype dormancy characteristics or foreseeing the appearance of new weed species in future agricultural scenarios. © 2019 Society of Chemical Industry 相似文献
997.
In the last year, a central issue in regional economic growth debate has been represented by the empirical analysis of Verdoorn's law related to the long‐term dynamic relationship between the rate of growth in output and the productivity growth due to increasing returns. Several papers have tested Verdoorn's law on European countries as well as many other world economies. Recently, attempts have been made to provide foundations for a spatial version of the original law specification. The main contributions were dedicated to the inclusion of spatial dependence in the economic model. Surprisingly, in the literature on Verdoom's law the analysis of the spatial heterogeneity is not often considered. The aim of this paper is the regional analysis of the spatial dependence and heterogeneity in Verdoorn's law, identifying spatial regimes that can be interpreted as clusters of productivity growth in European regions at NUTS 2 level. To pursue this objective, an optimization algorithm for the identification of groups is used. This constitutes a modified version of Simulated Annealing. 相似文献
998.
Development of a molecular marker for self‐compatible S4′ haplotype in sweet cherry (Prunus avium L.) using high‐resolution melting
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Claudia Muñoz‐Espinoza Evelyn Espinosa Roberto Bascuñán Sebastián Tapia Claudio Meneses Andréa Miyasaka Almeida 《Plant Breeding》2017,136(6):987-993
Sweet cherry (Prunus avium L.) has stylar gametophytic self‐incompatibility, which is controlled by the multi‐allelic S‐locus and encompasses the highly polymorphic genes for the S‐ribonuclease (S‐RNase) and S‐haplotype‐specific F‐box (SFB), which are female and male determinants, respectively. The self‐compatible mutant SFB4′ corresponds to an allele variant of SFB4 and presents a frameshift mutation. Even though male‐determinant molecular markers can discriminate between SFB4 and SFB4′ alleles, the methods required are laborious, time‐consuming and expensive, and not suitable for massive analysis and integration into breeding programmes. Our aim was to develop molecular markers for the evaluation of self‐compatibility alleles in sweet cherry, that could be used as a high‐throughput screening strategy to identify SFB4 and SFB4′ alleles, based on a marker for male determinacy. Our results were consistent using primers flanking the mutation responsible for the SFB4′ allele. We designed a specific molecular marker and confirmed it in sweet cherry commercial varieties. This new molecular marker is feasible for self‐compatibility alleles in the male determinant in sweet cherry‐assisted breeding programs. 相似文献
999.
Marcela Carvalho Andrade Alex Antônio da Silva Irã Pinheiro Neiva Izabela Regina C. Oliveira Evaristo Mauro De Castro David Merrill Francis Wilson Roberto Maluf 《Euphytica》2017,213(2):52
Tomato is affected by a large number of arthropod pests, among which the whitefly (Bemisia tabaci) is considered to be one of the most destructive. Several accessions of the wild species of Solanum galapagense, including accession LA1401, are considered resistant to whitefly (B. tabaci). This resistance has been associated with the presence of type IV glandular trichomes on the leaf surface. Our research aimed to study the inheritance of type IV glandular trichome density and its association with resistance to whitefly (B. tabaci biotype B) in populations derived from the interspecific cross Solanum lycopersicum × S. galapagense ‘LA1401.’ High estimates for both broad-sense and narrow-sense heritabilities of type IV glandular trichome densities suggest that inheritance of this trait is not complex. Whitefly resistance was associated with high density of type IV glandular trichomes. F2 (S. galapagense × S. lycopersicum) population plants selected for the highest densities of type IV glandular trichomes showed similar levels of resistance to those found in the donor of resistance LA1401. 相似文献
1000.
Paulo Roberto Campagnoli de Oliveira Filho Paulo José do Amaral Sobral Julio César de Carvalho Balieiro 《Journal Of Aquatic Food Product Technology》2017,26(3):325-334
This study compares how CO2 narcosis and thermal shock affect the physicochemical aspects of Nile tilapia fillets held frozen (?18°C) for up to 6 months. The characteristics of tilapia fillets subjected to CO2 narcosis were those of higher lightness and whiteness and lower redness. The hardness values of fillets of tilapia subjected to thermal shock were lower than those subjected to CO2 narcosis. During frozen storage to both treatments, the drip loss, denaturation of myosin, and lipid oxidation increased, while fillet water holding capacity and hardness decreased. The physicochemical properties of frozen fillets of tilapia stunned by CO2 narcosis were considered more desirable; therefore, the method can be a potential replacement to thermal shock. 相似文献