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551.
Summary The phenotype variation in six enzymes, 6-phosphogluconate dehydrogenase (6-PGD), malate dehydrogenase (MDH), peroxidase (PRX), isocitrate dehydrogenase (IDH), galactose dehydrogenase (GD) and glutamate oxaloacetate transaminase (GOT), was investigated using horizontal starch gel electrophoresis in 52 accessions of the grasspea, Lathyrus sativus. Phenotypic polymorphism was observed for all six enzymes. High phenotypic polymorphism (Pj) was observed for PRX and 6-PGD, while there was little polymorphism for GOT, with only two accessions showing variation. There was no correlation between phenotypic polymorphism and region of origin, or groupings of accessions made on the basis of flower colour. Tentative genetic interpretations of banding patterns are given for five of the enzyme systems. The level of apparent heterozygosity was higher than expected in this predominantly autogamous species. The level of variation in the grasspea is discussed in terms of its potential for exploitation through plant breeding. 相似文献
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Beatriz A. Acosta-Estrada Marco A. Lazo-VélezYazel Nava-Valdez Janet A. Gutiérrez-UribeSergio O. Serna-Saldívar 《Journal of Cereal Science》2014
Nejayote is the wastewater from the alkaline-cooking of maize and its solids are rich in dietary fiber (45.3%), calcium (5.7%) and ferulic acid (219 mg/100 g). Nejayote solids were used to develop a food additive (NS) consisting of 80% nejayote solids and 20% gluten. NS was incorporated at 3, 6 or 9%, in wheat flour to increase the dietary fiber, calcium, phenolics and antioxidant capacity of breads. The addition of 9% NS did not affect overall baking performance and bread quality but increased dietary fiber up to 54% in composite breads. Moreover, enriched breads contained about 745 times more free ferulic acid and increased approximately 70% their antioxidant capacity. Two slices of bread (64 g) supplemented with 9% of NS provided 29% of the recommended calcium intake. Thus, the NS could be used as a value-added food-ingredient for the preparation of composite bakery-products with improved dietary fiber, calcium, nutraceuticals and antioxidant properties. 相似文献
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Serena Khor Susanna A. Wood Lauren Salvitti David I. Taylor Janet Adamson Paul McNabb Stephen Craig Cary 《Marine drugs》2014,12(1):1-16
The origin of tetrodotoxin (TTX) is highly debated; researchers have postulated either an endogenous or exogenous source with the host accumulating TTX symbiotically or via food chain transmission. The aim of this study was to determine whether the grey side-gilled sea slug (Pleurobranchaea maculata) could obtain TTX from a dietary source, and to attempt to identify this source through environmental surveys. Eighteen non-toxic P. maculata were maintained in aquariums and twelve were fed a TTX-containing diet. Three P. maculata were harvested after 1 h, 24 h, 17 days and 39 days and TTX concentrations in their stomach, gonad, mantle and remaining tissue/fluids determined using liquid chromatography-mass spectrometry. Tetrodotoxin was detected in all organs/tissue after 1 h with an average uptake of 32%. This decreased throughout the experiment (21%, 15% and 9%, respectively). Benthic surveys at sites with dense populations of toxic P. maculata detected very low or no TTX in other organisms. This study demonstrates that P. maculata can accumulate TTX through their diet. However, based on the absence of an identifiable TTX source in the environment, in concert with the extremely high TTX concentrations and short life spans of P. maculata, it is unlikely to be the sole TTX source for this species. 相似文献
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Stronger collaboration between government organizations (GOs), NGOs, and rural people has long been advocated as a means of enhancing the responsiveness, efficiency, and accountability of GOs and NGOs. This paper reviews the arguments and evidence for specific types of collaboration for sustainable agricultural development, setting it into the context of Korten's (1980) concept of “learning process.” Taking recent examples from Udaipur District in India, it reviews the experiences and potential of collaboration, arguing that, while informal interaction increases and enriches the fabric of pluralist development, certain strategic decisions often require a degree of formality. These include decisions on the development of human resources — here both the users and providers of services. Moreover, human resource development (HRD) must be viewed in the context of the mandates, aspirations, and systems of accountability and rewards of the institutions concerned. These determine whether institutions develop and expand their own human resources or draw upon those of others by collaborating with them. Individuals engaged in these organizations can be more effectively induced to collaborate with others by combinations of flexibility and appropriate reward systems than they can be forced to do so by instructions or commands. Several conclusions follow: decisions to act together are unlikely to progress unless translated into concrete actions; authority to take local-level decisions in GOs needs strengthening if they are to provide the necessary flexibility; and, although collaboration should in principle be built on the comparative advantage of different types of organization, in practice, each will have to incorporate the skills of the other, at least to some level, if they are to communicate effectively. NGOs and GOs must also enhance their understanding of farmers' ability to make demands on external organizations. Edging towards collaboration is a delicate and painstaking process. Only if many of the above conditions are given due priority will early examples have something to offer to the numerous NGOs, GOs and international agencies wishing to learn from them. 相似文献
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