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Six high protein and high lysine barley lines were derived from four crosses involving high protein andlor high lysine donors, ie Riso 1508 and SV 73608 (Hiproly×Mona5), with well adapted local strains V 5681 and V 4342. The trial was grown at the Wheat Research Institute, Faisalabad, Pakistan. The lines were chemically and nutritionally characterized and the results were compared with the parents. The biological value, net protein utilization and lysine contents were higher in all the derived lines than in their local parents, ie V 5681 and V 4342. The increased lysine levels in the lines B 82503 and B 82507 may be a consequence of the reduction of prolamin fractions with simultaneous increases in salt soluble fractions. In all the lines, lysine and nutritional quality increase were a reflection of high protein andlor high lysine parents. The line B 82503 had grain yield comparable to its local parent V 5681 but it was superior in lysine and some nutritional attributes to its high lysine donor parent Riso 1508. In some lines, lysine improvement was achieued without impairing grain yield.  相似文献   
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In the present study, crude polysaccharides from Ziziphus Jujuba cv. Muzao were isolated and purified using DEAE cellulose-52 and Sephadex G-100 size-exclusion chromatography; four fractions were collected, namely GZMP-1, GZMP-2, GZMP-3, and GZMP-4. The molecular weights of these four fractions were measured to be 111.2, 95.1, 84.2, and 571.4 kDa, respectively, using high-performance gel permeation chromatography. Gas chromatography analysis of the monosaccharide composition confirmed that GZMP-1 was composed of rhamnose, arabinose, glucose, and galactose. Rhamnose, arabinose, and galactose were the main components present in GZMP-2 and GZMP-3, whereas GZMP-4 was composed of only rhamnose and arabinose. Scanning electron microscopy showed relatively smooth surfaces for GZMP-1 and GZMP-4, whereas GZMP-2 and GZMP-3 had more folds on their surfaces. Fourier transform infrared spectroscopy analyses indicated that GZMP-1 and ZMP mainly had α-type glycosidic linkages. The in vitro antioxidant activities of the polysaccharides revealed that jujube polysaccharides exhibit remarkable antioxidant activity, and can scavenge DPPH radical and OH radical in a concentration-dependent manner. The results of this work suggest that polysaccharides from Z. Jujuba cv. Muzao have potential to be used as functional food and in the development of natural antioxidant drug carriers.  相似文献   
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Whey and its components are recognized as value-added ingredients in infant formulas, beverages, sports nutritious foods, and other food products. Whey offers opportunities for the food industrial sector to develop functional foods with potential health benefits due to its unique physiological and functional attributes. Despite all the above importance, the consumption of whey protein (WP) can trigger hypersensitive reactions and is a constant threat for sensitive individuals. Although avoiding such food products is the most successful approach, there is still a chance of incorrect labeling and cross-contamination during food processing. As whey allergens in food products are cross-reactive, the phenomenon of homologous milk proteins of various species may escalate to a more serious problem. In this review, nonthermal processing technologies used to prevent and eliminate WP allergies are presented and discussed in detail. These processing technologies can either enhance or mitigate the impact of potential allergenicity. Therefore, the development of highly precise analytical technologies to detect and quantify the existence of whey allergens is of considerable importance. The present review is an attempt to cover all the updated approaches used for the detection of whey allergens in processed food products. Immunological and DNA-based assays are generally used for detecting allergenic proteins in processed food products. In addition, mass spectrometry is also employed as a preliminary technique for detection. We also highlighted the latest improvements in allergen detection toward biosensing strategies particularly immunosensors and aptasensors.  相似文献   
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A new, compact gas/particle ion chromatograph has been developed for measuring ionic constituents in PM2.5 (particulate matter of aerodynamic diameter < or = 2.5 microm) and water-soluble ionogenic gases. The instrument has separate sampling channels for gases and particles. In one, a membrane denuder collects soluble gases for preconcentration and analysis. In the other, a cyclone removes larger particles, a membrane denuder removes soluble gases, and a continuously wetted hydrophilic filter collects particles. A single, multiport, syringe pump handles liquid transport, and one conductivity detector measures anions and ammonium for both channels. Electrodialytically generated gradient hydroxide eluent permits 20 min chromatographic runs. Gas/particle samples are each collected for 40 min, butthe sampling intervals are staggered by 20 min. Liquid samples from the gas denuder and particle collector are aspirated and preconcentrated on sequential cation and anion concentrators and transferred respectively to an ammonia transfer device and an anion separation column. The flow configuration results in an ammonium peak before anion peaks in the chromatogram. The system measures ammonia, organic acids (such as acetic, formic, and oxalic acids), HCl, HONO, SO2, HNO3, and the corresponding ions in the aerosol phase. Low ng/m3 to sub-ng/m3 limits of detection (LODs) are attained for most common gases and particulate constituents, the LODs for gaseous SO2 to NH3 range, for example, from sub parts per trillion by volume (sub-pptv) to approximately 5 pptv.  相似文献   
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Two experiments were conducted in a camel cheese study to (i) compare camel cheese to bovine cheese made from bovine milk standardised to simulate camel milk, and (ii) describe the technology for manufacture of dry (SCC‐D) and brine‐salted soft camel cheese (SCC‐B). Comparable cheese yield (camel: 7.4 ± 0.15, cow: 7.3 ± 0.55 kg/100 kg of milk) and levels of dry matter loss in whey were observed. Clotting time was 234 s for both cheeses which were made using thermophillic starters. Cheese yield was 9.31 ± 0.64 kg/100 kg with 425.6 ± 38.2 g/kg cheese dry matter for SCC‐D and 8.22 ± 0.90 kg/100 kg with 469 ± 73.8 g/kg dry matter for SCC‐B.  相似文献   
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