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排序方式: 共有818条查询结果,搜索用时 31 毫秒
791.
Muir JG Shepherd SJ Rosella O Rose R Barrett JS Gibson PR 《Journal of agricultural and food chemistry》2007,55(16):6619-6627
Fructans are not digested in the small intestines of humans. While many health benefits have been attributed to these carbohydrates, they can cause gastrointestinal symptoms in some individuals. We measured the total fructans in 60 vegetables and 43 fruits using the Megazyme fructan assay. Vegetables with the highest quantity of fructans included garlic, artichoke, shallots, leek bulb, and onions (range, 1.2-17.4 g/100 g fw). Fruits with low, but detectable, fructans included longon, white peach, persimmon, and melon (range, 0.21-0.46 g/100 g fw). The fructan assay was modified to provide an estimate of the average chain length (degree of polymerization) for high fructan vegetables. d-Fructose can also be malabsorbed in the small intestine of humans, so the d-fructose content in some foods was measured to supplement the current food tables. Research in this area will be facilitated through the availability of more comprehensive food composition data. 相似文献
792.
The structure and physicochemical properties of waxy, common, and high‐amylose corn starch phosphates prepared by oven heating were studied. Starch phosphates prepared by either slurry or dry‐mixing treatment before oven heating were also compared. The slurry treatment more efficiently incorporated phosphorus into starch relative to the dry‐mixing treatment under the reaction conditions studied. In general, the phosphorylated starch prepared by the slurry treatment exhibited a lower gelatinization temperature, a higher peak viscosity, a lesser degree of retrogradation, and improved freeze‐thaw stability compared with those prepared by the dry‐mixing treatment. Phosphorylation occurred probably in both amylose and amylopectin, and the amount and location of incorporated phosphate groups varied with starch types likely due to their different amylose and amylopectin contents. Waxy starch was more prone to phosphorylation, followed by common and high‐amylose starches, respectively. 相似文献
793.
High‐intensity ultrasound was evaluated as an alternative method to isolate rice starch without the use of chemicals as in the traditional alkaline steeping method. Surfactants, including sodium dodecyl sulfate (SDS), sodium stearoyl lactylate (SSL), and Tween 80, at 0.1, 0.3, or 0.5% combined with high‐intensity ultrasound were also investigated for rice starch isolation. A rice flour slurry (33%) was subjected to sonication for 15, 30, or 60 min at an amplitude of 25, 50, or 75% and at 40 or 50°C. The starch yield was not significantly affected by the treatment temperature and ranged from 46.7 to 76.2% (starch dry basis) after the sonication treatment; the protein and damaged starch contents of the isolated starches were 0.9–1.7% and 3.1–3.5% (dry basis), respectively. The combination of 0.5% SDS and high‐intensity ultrasound improved the starch yield to 84.9% with low residual protein, however, little improvement was observed with SSL or Tween 80. The pasting properties of isolated starch as measured by a Rapid Visco‐Analyser were affected by the treatment temperature and by the amount of residual protein and damaged starch. The thermal properties of the isolated starch were not changed by sonication and the amylose content remained unchanged. The surface of the isolated starch was not damaged by sonication as shown by scanning electron microscopy. High‐intensity ultrasound, alone or combined with SDS, showed a great potential for rice starch isolation in a short period of time without generating alkaline effluent. 相似文献
794.
795.
Grazieli Maboni E. Jane Kelly Chad S. Clancy Eliana De Luca Thomas J. Baldwin Arnaud J. Van Wettere Albert J. Kane Summer Peterson V. Gus Warr Dona A. Bastian Susan Sanchez 《Journal of veterinary diagnostic investigation》2022,34(1):167
A mortality event among recently captured feral donkeys (Equus asinus) occurred in south-central Utah in 2016. The deaths were sporadic, and clinical signs were indicative of respiratory disease, likely associated with an infectious etiology. Ten of 13 donkeys autopsied had moderate-to-severe interstitial fibrosing pneumonia, and one had pyogranulomatous pneumonia. Consensus PCRs directed toward the DNA polymerase and DNA packaging terminase subunit 1 for herpesviruses were performed followed by sequencing of the PCR amplicons and phylogenetic analysis. Asinine herpesvirus 4 (AsHV4) and 5 (AsHV5) were consistently identified in lung tissues of affected donkeys. No other herpesviruses were identified, and herpesviral DNA was not detected in lung tissues of 2 donkeys without evidence of respiratory disease. The detection of asinine gammaherpesviruses may have been associated with the lesions described. AsHV4 and AsHV5 have been reported in previous studies as novel gammaherpesviruses based on sequences obtained from donkeys with interstitial pneumonia and marked syncytial cell formation. Our findings suggest that the association of asinine gammaherpesviruses with respiratory conditions in equids deserves further attention. 相似文献
796.
797.
The ecogeography and collection of grain, forage and pasture legumes in south-west Turkey 总被引:1,自引:0,他引:1
Sarita Jane Bennett Nigel Maxted Cafer Olcayto Sabanci 《Genetic Resources and Crop Evolution》1998,45(3):253-262
A collecting mission took place in June and July 1996 to collect legume species from south-west Turkey and western Anatolia. Sites were chosen to maximise the diversity of legumes collected and detailed passport data were recorded at each site. A total of 96 sites were visited, and 1307 accessions collected. In total 23 genera were collected, of which the most frequently seen were Trifolium, Medicago and Vicia. Sites were found to be almost exclusively calcareous with a pH range of 7 to 10, and varied from sea level to 1750m. Many of the Trifolium species are of economic importance for southern Australia and have been shown to display characters such as a high productivity (T. michelianum) and waterlogging tolerance (T. resupinatum and T. tomentosum). The Medicago species were found to prefer well-drained habitats in open areas. Many of these species can tolerate heavy grazing. The two main forage legume genera collected were Lathyrus and Vicia. Both of these occurred on the higher pH soils and were most frequently collected from the lower altitudes. Four species of grain legume were found, Cicer arietinum, Lens culinaris, Pisum sativum and Vicia faba. The material collected during this mission is important in the drive to preserve the legume genetic diversity of Turkey, the species' centre of diversity, for utilisation both within and outside of Turkey. 相似文献
798.
799.
800.
The objective of this study was to screen starches recovered from the corn accessions used in the Germplasm Enhancement of Maize (GEM) project for unusual thermal properties and paste and gel behaviors, so that they could be exploited in corn breeding programs to enhance traits important to corn utilization. In general, the values for gelatinization temperatures and peak height indices were greater, but heat of gelatinization values were less for the starches recovered from the GEM accessions (particularly BRA 052051 (SE 32)) than for starches from commercial Dent corn hybrids (11.3 vs. 13.6 J/g). Generally, retrogradation properties were similar among the GEM accessions, although there were specific accessions (particularly Lima 13) that possessed modestly lower percentage retrogradation (34 vs. 42%). Generally, peak viscosities, cold paste viscosities, and viscosity breakdowns were greater for the starches of the GEM accessions (particularly ARZM 01150, Antiqua 3, and URZM 01089, respectively) than for the starches of commercial hybrids. Pasting temperatures were about the same for all starches. Both 1‐day and 7‐day gel strengths were considerably greater for the starches recovered from the GEM accessions (particularly BRA 052051 (SE 32), 21.0 g for 1‐day and FS8A(T), 66.2 g for 7‐day). Although the differences in starch properties were statistically different, only the higher gel strengths of the starches recovered from the GEM accessions were of practical significance to the starch industry. 相似文献