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971.
Cell wall proteins (CWPs) play a vital role in the development of the different morphological stages including mycelium, fruiting body, and sclerotium in mushrooms which are important human food sources. Using fractionation by detergents and reducing agents, mushroom cell wall fractions from the different developmental stages of Pleurotus tuber-regium (PTR) were prepared. Using one-dimensional gel electrophoresis coupled with LC-MS, there were 103, 91, and 48 noncovalently linked CWPs identified in the cell wall fractions of the PTR mycelium, fruiting body, and sclerotium, respectively. Comparing the CWPs in these cell wall fractions, 19 of them were in common, among which 17 belonged to the functional categories of translation, ribosomal structure, and biogenesis. This is the first study to provide important biochemical insights into the different developmental stages of PTR mediated by CWPs, and the identified CWPs helped to explain the morphological changes of PTR mushrooms during cultivation.  相似文献   
972.
Approximately 20-25% of babies consuming formula are fed formulas containing soy protein as the sole protein source. Isoflavone phytoestrogens are considered as major bioactive components present in soy protein isolate (SPI) and the most widely studied phytochemicals in human diets and soy infant formulas. In the present study, LC-MS/MS analysis of SPI phytochemical extract resulted in identifications of fifty-six lysophospholipids (lyso-PL), including eighteen lysophosphatidylcholines (lyso-PC), twelve lysophosphatidylethanolamines (lyso-PE), eleven lysophosphatidylinositols (lyso-PI), eleven lysophosphatidic acids (lyso-PA) and four lysophosphatidylglycerols (lyso-PG). The LC-MS/MS conditions were first developed using commercially available standard mixtures. Under these conditions, lyso-PL compounds could be separated by LC and yielded unique fragments and neutral losses in the electrospray ionization mass spectrometry (ESI-MS) with both positive- and negative-ion modes, quite indicative of the polar headgroups for different subclasses. This is the first characterization of lyso-PL in SPI. Lyso-PLs are important cell signaling and growth factor molecules experimentally linked to cardiovascular function and disease, cancer, and neurological disorders. These findings suggest that biological effects of PLs associated with SPI in infants clearly needs to be considered as part of an overall evaluation of potential health benefits.  相似文献   
973.
Summary After having finished in 1985 the collection of plant-genetic resources in Western Georgia (the results have been summarized in some tables) joint activities for the collection of indigenous taxa of cultivated plants began for Eastern regions of the Georgian SSR in 1986. The mission took place within the rayon Dueti, which is highly differentiated in geographical respect and stretches beyond the main ridge of the Great Caucasus. Althogether 265 samples could be collected, grain legumes and vegetables represent the most numerous groups but the amount of cereal accessions is not much less; this contrasts sharply with the results from the missions in Western Georgia. The gene-erosion is very advanced in Dueti too, especially for cereals.Triticum carthlicum, T. dicoccon and naked barleys have disappeared within the last decades from the fields. However in isolated settlements the cultivation of old local races ofT. aestivum as well as of barley and rye had been maintained up till now. For breeding purposes and botanically interesting material could be collected also from vegetables, spice plants and grain legumes. Some examples have been shortly characterized.
Sammlung pflanzen-genetischer Ressourcen in der Georgischen SSR 1986
Zusammenfassung Nachdem 1985 die Sammlungen pflanzen-genetischer Ressourcen in Westgeorgien abgeschlossen wurden (in einigen Tabellen werden die Sammelergebnisse kurz zusammengefaßt), wurde 1986 die gemeinsame Sammeltätigkeit zur Erfassung indigener Kulturpflanzen-Sippen in östlichen Gebieten der Georgischen SSR aufgenommen. Die Reise führte in den Rayon Dueti, der geographisch sehr differenziert ist und bis jenseits des Kaukasus-Hauptkammes reicht. Es konnten insgesamt 265 Proben gesammelt werden, unter denen Körnerleguminosen und Gemüse den Hauptanteil einnehmen, denen aber die Getreide (im Gegensatz zu den Sammelergebnissen in Westgeorgien) nur wenig nachstehen. Die Generosion ist auch hier vor allem bei den Getreiden sehr weit fortgeschritten;Triticum carthlicum, T. dicoccon sowie Nacktgersten sind in den letzten Jahrzehnten aus dem Anbau verschwunden. Jedoch hat sich in entlegenen Siedlungen noch die Kultur alter Lokalsorten vonTr. aestivum sowie von Gerste und Roggen erhalten. Auch von Gemüsen, Gewürzpflanzen und Körnerleguminosen konnte botanisch und züchterisch interessantes Material gesammelt werden. Einige Beispiele davon werden kurz charakterisiert.

- 1986
1985 - ( ¶rt;), 1986 , . ¶rt; , . , , 265 , , , , . ¶rt;, , Triticum carthlicum, T. dicoccon . , Tr. aestivum . , , , . .
  相似文献   
974.
Isoflavone phytoestrogens found in soybeans are the most widely studied phytochemicals in human diets and soy infant formulas. The health benefits of the isoflavones daidzein and genistein have been reported, and concerns about potential adverse effects have also been raised. However, the results of direct analysis of isoflavones and their metabolites in biological fluids after consumption of soy-containing diets are scarce. This study describes an LC/MS/MS method for the analysis of isoflavones and their metabolites in the urine of female rats fed diets made with soy protein isolate. Five isoflavones (daidzein, genistein, glycitein, dihydrodaidzein, and O-desmethylangolensin) were identified by comparison with authentic standards. Seventeen conjugates of isoflavones were characterized in the urine, the most unusual being genistein 5-glucuronide and four glucuronide conjugates of reductive metabolites of daidzein. The application of LC/MS/MS to analyze isoflavone metabolites is simple and sensitive, and appears to be an excellent method for determining the bioavailability and metabolism of food phytochemistry.  相似文献   
975.
Inoculation at the time of planting with Pseudomonas chlororaphis strain 2E3 increased the emergence of spring wheat by 8% and 6% at two different sites in northern Utah. Isolate 2E3 strongly inhibited the growth of the wheat pathogen Fusarium culmorum on artificial media. A second isolate of P. chlororaphis (strain O6) also inhibited fungal growth on artifical media but did not increase emergence of the spring wheat at the same field sites. Inoculation of winter wheat by 2E3 did not promote emergence when planted into field soil sterilized by fumigation with methyl bromide. Under laboratory conditions, emergence of spring wheat in sterilized soils from both sites was at least 90%. In the soils that were not sterilized, emergence was below 25% in soil from one site and below 50% in soil from the other. Treating seeds with 2E3 significantly improved emergence in a sterile soil-containing matrix that had been inoculated with the wheat pathogen Fusarium culmorum. Consequently, we propose that increases in wheat emergence can be attributed to the suppression by 2E3 of pathogenic organisms present in the native field soils. A strain of Rhizoctonia solani, shown to the pathogenic on winter wheat, was isolated from one of these soils.  相似文献   
976.
Oxygen profiles and methane turnover in a flooded rice microcosm   总被引:19,自引:0,他引:19  
Summary Dissolved O2 was depleted within the top 3.5-mm surface layer of flooded rice soil microcosms without plants. In planted microcosms, however, O2 was detectable down to at least 40 mm in depth. O2 concentrations in the uppermost soil layers of microcosms with rice plants were higher in the light than in the dark, indicating O2 production by photosynthesis. The CH4 emission rates were nearly identical for illuminated and for darkened microcosms, demonstrating that the photosynthetically produced O2 did not increase CH4 oxidation in the rhizosphere. In contrast, CH4 emission rates increased when the microcosms were incubated under an N2 atmosphere, indicating that transport of O2 from the atmosphere into the rhizosphere was important for CH4 oxidation. CH4 emission under air accounted for only 10%–20% of the cumulative CH4 production determined in cores taken from the microcosms. Apparently, 80%–90% of the CH4 produced was oxidized in the rhizosphere and thus was not emitted.  相似文献   
977.
978.
Application of an aroma extract dilution analysis on an aroma distillate prepared from organically grown, raw West-African peanuts (Cameroon) revealed 36 odor-active areas in the flavor dilution (FD) factor range of 1 to 2048. The identification experiments, which were all performed by using the respective reference chemicals, revealed 2-isopropyl-3-methoxypyrazine (earthy, pea-like), 2-isobutyl-3-methoxypyrazine (bell pepper-like, earthy), and trans-4,5-epoxy-(E)-2-decenal (metallic) with the highest FD factors among the 36 aroma compounds identified. The two last mentioned odorants and another set of 22 further odorants were identified for the first time in raw peanuts. A comparative aroma extract dilution analysis applied on distillates prepared from either the raw peanuts or ground peanut meal roasted in a pan showed 52 odor-active areas in the FD factor range of 8 to 2048 in the roasted nut material. The identification experiments in combination with the FD factors revealed that among them, 2-acetyl-1-pyrroline and 4-hydroxy-2,5-dimethyl-3-(2H)-furanone showed the most significant contribution to the overall aroma, followed by 1-octen-3-one, 2-isopropyl-3-methoxypyrazine, (E, E)-2,4-decadienal, and trans-4,5-epoxy-(E)-2-decenal. As a further result, 20 aroma compounds were newly identified in roasted peanuts, such as 2-propionyl-1-pyrroline and 2-acetyltetrahydropyridine (both popcorn-like). In particular, 2-acetyl-1-pyrroline and 4-hydroxy-2,5-dimethyl-3(2 H)-furanone showed the most pronounced increase after roasting.  相似文献   
979.
The objective of this study was to establish a withdrawal period for flunixin in milk by quantifying 5-hydroxyflunixin, the marker residue, in bovine milk as a function of time, following intravenous treatment of lactating dairy cows with flunixin-N-methyl glucamine (Banamine or Finadyne). Lactating dairy cows were dosed on three consecutive days at 2.2 mg of flunixin free acid/kg of body weight/day. Milk was collected twice daily and assayed using a liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) procedure. The method was validated at concentrations in the range 0.5-250 ppb. The concentrations for 5-hydroxyflunixin measured 12 h after the last administration of drug ranged from 1.56 to 40.6 ppb for all cows. Milk concentrations for 5-hydroxyflunixin were used to establish withdrawal periods of 36 h using guidelines established by the U.S. Food and Drug Administration/Center for Veterinary Medicine and 24 h using guidelines established by the European Medicinal Evaluation Agency/Committee on Veterinary Medicinal Products.  相似文献   
980.
Summary Highly pseudo-self compatible (PSC) Nemesia strumosa plants were selfed and intercrossed to produce progenies of the F5 through F7 generations. Though high PSC progenies were obtained, none were truebreeding. Progenies from crossing inbred high PSC plants to low PSC plants consisted of either mostly low PSC plants or both low and intermediate plants. A backcross to the high PSC parent of a progeny from a low times high cross produced a family with a PSC frequency distribution skewed toward low PSC but with a few high PSC plants. These data may be explained if PSC genes at some or most loci are incompletely dominant to non-PSC genes and threshold numbers of PSC genes are required for PSC expression and for 100% PSC plants. Dominance may also occur at some loci. Although only a small number of genes may be required to produce a high PSC plant, the total number of PSC genes may be large.Scientific Journal Series Paper No. 11,676 of the Minnesota Agricultural Experiment Station.  相似文献   
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