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垃圾渗滤液中往往含有高浓度的有机物、氨氮等污染物。异养硝化-好氧反硝化型微生物能在脱氮的同时去除部分有机物,但目前对于相关混合菌剂直接应用于垃圾渗滤液处理的研究较少。从垃圾渗滤液中筛选出6株异养硝化-好氧反硝化菌株并组配成复合菌剂F6,探究菌剂在垃圾渗滤液中的脱氮效果。分别以单一菌株和复合菌剂F6为投放原料;以不同碳氮比、活性炭浓度、转速以及微量元素浓度为影响因素,研究复合菌剂对于垃圾渗滤液中氨氮(NH4+-N)、总氮(total nitrogen, TN)、化学需氧量(chemical oxygen demand, COD)的去除性能。结果表明,提高碳氮比和微量元素浓度能够促进复合菌剂F6的降解效果;当接种量为10%、碳氮比为15%时,F6对NH4+-N、TN、COD的去除率分别为74.69%、89.23%和83.50%,与不添加活性炭的处理相比,分别提高了约18.46%、20.97%和7.98%。复合异养硝化-好氧反硝化菌剂F6对高氨氮垃圾渗滤液去除NH4+-N、TN、COD等方面具有良好的应用前景。  相似文献   

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《Cell reports》2023,42(8):112939
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The ratio of substrates and products (mass action ratio) for the reaction catalyzed by the enzyme pyruvate kinase is measured under the constraint of constant reaction rate for pyruvate kinase (EC 2.7.1.40) from brewers yeast and Eschcrichiacoli. For both organisms, a maximum of the ratio is found at concentrations comparable to those obtained from cell metabolite measurements. This observation suggests an optimum principle for free energy transduction in the glycolytic reaction pathway. as a maximum of the mass action ratio corresponds to a minimum dissipation of free energy.  相似文献   

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Zhang S  Sakuradani E  Ito K  Shimizu S 《FEBS letters》2007,581(2):315-319
A new gene encoding a delta12 fatty acid desaturase-related protein was cloned from a multicellular basidiomycete Coprinus cinereus TD#822-2. The 1326 bp full-length gene, designated as Cop-odeA, codes for a putative protein of 442 amino acids with a MW of 49224. The Cop-odeA yeast transformant accumulated four new fatty acids identified as 9,12-hexadecadienoic acid, 9,12,15-hexadecatrienoic acid, linoleic acid, and alpha-linolenic acid, which comprised 8.8%, 1.0%, 29.0%, and 0.6% of the total fatty acids, respectively. The Cop-odeA protein was confirmed to be a novel bifunctional fatty acid desaturase with both high delta12 desaturase activity and unusual delta15 desaturase activity.  相似文献   

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《Cell reports》2023,42(4):112271
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《Cell reports》2023,42(6):112569
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The genotoxic activity of environmental xenobiotics is manifested either in their direct interaction with cellular genetic material or in provoking secondary events, among which reactive oxygen species (ROS) production is a common phenomenon. Both pathways can be mediated by the activity of the cytochrome P450 monooxygenase system. We studied induction of the CYP 1A or CYP 2B monooxygenases in rat liver by the fungicides: thiram, captan, captafol, dodine and the drugs: nitrofurazone, furazolidone and the plant flavonoid: quercetin. A cytochrome P450 induction assay (CYPIA test) was used. S9 prepared from livers of rats treated with the test compounds were used to activate ethidium bromide (EtBr) (CYP 1A isoenzyme) or cyclophosphamide (CPA) (CYP 2B isoenzyme) in the Ames test.It was found that among the tested compounds, the most potent inducer of CYP 1A was furazolidone (3× 80 mg/kg). Less potent was thiram (1× 100 mg/kg), as well as quercetin (3× 80 mg/kg), and captafol (1× 30 mg/kg). On the other hand, thiram (1× 100 mg/kg), captafol (1× 30 mg/kg), and quercetin (3× 80 mg/kg) were most potent in the CYP 2B isoenzyme induction, while furazolidone (3× 80 mg/kg), and nitrofurazone (3× 80 mg/kg) appeared to be less potent in this respect. Captan and dodine (3× 80 mg/kg) did not affect the activity of any of the cytochrome P450 isoenzymes.  相似文献   

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Shulga YV  Topham MK  Epand RM 《FEBS letters》2011,585(24):4025-4028
We show that diacylglycerol kinase-ε (DGKε) has less preference for the acyl chain at the sn-1 position of diacylglycerol (DAG) than the one at the sn-2 position. Although DGKε discriminates between 1-stearoyl-2-arachidonoyl-DAG and 1-palmitoyl-2-arachidonoyl-DAG, it has similar substrate preference for 1-stearoyl-2-arachidonoyl-DAG and 1,2-diarachidonoyl-DAG. We suggest that in addition to binding to the enzyme, the acyl chain at the sn-1 position may contribute to the depth of insertion of the DAG into the membrane. Thus, the DAG intermediate of the PI-cycle, 1-stearoyl-2-arachidonoyl-DAG, is not the only DAG that is a good substrate for DGKε, the DGK isoform involved in PI-cycling.  相似文献   

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Received 1 September 2001/ Accepted in revised form 15 October 2001  相似文献   

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α -amylase as well as other enzymes involved in starch degradation under anoxia. Carbohydrates resulting from starch breakdown allow maize caryopses to avoid sugar starvation. Most interestingly, this correlates well with the ability of maize caryopses to sustain relatively prolonged anaerobiosis, in agreement with the hypothesis linking carbohydrate availability to anoxia tolerance. Received 25 September 1999/ Accepted in revised form 24 February 2000  相似文献   

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Using mass spectrometry (MS), we examined the impact of endothelial lipase (EL) overexpression on the cellular phospholipid (PL) and triglyceride (TG) content of human aortic endothelial cells (HAEC) and of mouse plasma and liver tissue. In HAEC incubated with the major EL substrate, HDL, adenovirus (Ad)-mediated EL overexpression resulted in the generation of various lysophosphatidylcholine (LPC) and lysophosphatidylethanolamine (LPE) species in cell culture supernatants. While the cellular phosphatidylethanolamine (PE) content remained unaltered, cellular phosphatidylcholine (PC)-, LPC- and TG-contents were significantly increased upon EL overexpression. Importantly, cellular lipid composition was not altered when EL was overexpressed in the absence of HDL. [14C]-LPC accumulated in EL overexpressing, but not LacZ-control cells, incubated with [14C]-PC labeled HDL, indicating EL-mediated LPC supply. Exogenously added [14C]-LPC accumulated in HAEC as well. Its conversion to [14C]-PC was sensitive to a lysophospholipid acyltransferase (LPLAT) inhibitor, thimerosal. Incorporation of [3H]-Choline into cellular PC was 56% lower in EL compared with LacZ cells, indicating decreased endogenous PC synthesis. In mice, adenovirus mediated EL overexpression decreased plasma PC, PE and LPC and increased liver LPC, LPE and TG content. Based on our results, we conclude that EL not only supplies cells with FFA as found previously, but also with HDL-derived LPC and LPE species resulting in increased cellular TG and PC content as well as decreased endogenous PC synthesis.  相似文献   

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A holocellulose fraction was isolated from the inner bark of Psedotsuga menziesii and analyzed. It was composed of acid-insoluble lignin (3·1 acid-soluble lignin (4·1%), l-arabinose (2·6%), d-xylose (6.3%). d-mannose(9·5%), d-galactose (2·3%), and d-glcose (61·1%). The presence of these sugars and their configurations were positively established by the preparation of crystalline derivatives. The holocellulose was fractionated into its component polysaccharides, a xylan, a galactoglucomannan, a glucomannan, and a glucan-rich residue.  相似文献   

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Abstract The inhibitory effects of several alcohols identified from male hairpencil of cotton bollworm on conspecific male behavior responses were studied. In the wind tunnel dose tests ranging from 4 × lop4 to 40 pg, male moths of cotton bollworm produced the highest response to the binary components of 29–16: Ald and Z11 —16: Ald in a ratio of 5 : 95 at the dosage of 0.4 μg. When 211–16:OH was added to 0.4 μg dose of binary blend, 5% of the alcohol completely inhibited male orientation behavior. Further increment of percentage of alcohol in binary blend inhibited not only orientation behavior but also takeoff behavior. Comparisons among 211 —16: OH and other three saturated alcohols, 14 : OH, 16 : OH, and 18 : OH as well as structurally similar compound Z9–16: OH indicated that Z11–16: OH was more effective in inhibiting male orientation behavior than other tested alcohols. Field application of 211–16: OH decreased egg hatch rate from untreated 34% to 17% by spraying or coating the alcohal on plastic tubes.  相似文献   

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 Nectarless flowers of Cypripedium macranthos var. rebunense are pollinated by only queen Bombus pseudobaicalensis, which also pollinates nectar-producing flowers of Pedicularis schistostegia. Our previous study (Sugiura et al. 2001) suggested that they form a floral mimicry system: (1) Flowering phenology of both plants overlapped greatly. (2) Cypripedium occurred with lower frequency relative to Pedicularis. And (3) in a mixed stand of both plants, foraging bumblebees were sometimes confused between the mimic and model flowers. The present study clarified the system with new evidence. (4) Flower colour of Cypripedium and Pedicularis would be similar within the range of a bumblebee's visual spectrum. And (5) both species largely overlapped in spatial distribution. Based on these findings, we discuss how C. macranthos var. rebunense differs in pollination mechanism from other congeneric species, especially C. calceolus. Received April 23, 2002; accepted August 23, 2002 Published online: November 28, 2002 Addresses of the authors: Naoto Sugiura (e-mail: sugiura@aster.sci.kumamoto-u.ac.jp), Department of Environmental Science, Faculty of Science, Kumamoto University, Kumamoto 860-8555, Japan. Masashi Goubara, United Graduate School of Agricultural Sciences, Tottori University, Tottori 680-8553, Japan. Kenji Kitamura, Division of Environmental Biology, Faculty of Life and Environmental Science, Shimane University, Mastue 690-8504, Japan. Ken Inoue, Biological Institute and Herbarium, Faculty of Science, Shinshu University, Matsumoto 390-8621, Japan.  相似文献   

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 This paper deals with the use of cladistic methods and cladograms in phylogeny reconstruction in plant groups containing numerous taxa. How accurate are the cladograms as to details? Accuracy tests at the level of details require an independently known phylogeny, which excludes most plant groups, but such tests can be carried out in domesticated and experimental plant groups which have documented pedigrees. Four such tests are known and are presented here: a new case in Gilia and three previously published cases in Avena, Hordeum, and Helianthus. The four cases include domesticated and experimental plants, use of morphological and molecular evidence, and presence of dichotomous as well as reticulate phylogenies. The cladograms of the four plant groups all differ in significant details from the known pedigrees. These results are discussed in relation to problems of interpretation of cladograms. Received March 21, 2000 Accepted August 16, 2001  相似文献   

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 In this study we construct a phylogenetic hypothesis for the relatedness among disjunct subspecies of Cyclamen repandum and its two allopatric congeners, C. creticum and C. balearicum in order to examine the evolutionary divergence of currently isolated populations across the western Mediterranean. The most parsimonious phylogenetic tree obtained from sequencing the cpDNA trnL (UAA) intron suggests a major phylogeographic divide in southern Greece between two clades. The first clade comprises samples of C. repandum subsp. peloponnesiacum (from the Peloponnese) and C. creticum (from Crete). The second comprises samples of C. repandum subsp. repandum (from Croatia, Italy, southern France, Corsica, Sardinia and Sicily), C. repandum subsp. rhodense (from Rhodes and Kos) and C. balearicum (from the Balearic Islands and southern France). These data suggest that C. creticum has evolved in allopatry from C. repandum subsp. peloponnesiacum and that C. balearicum and C. repandum ssp. rhodense have diverged from C. repandum subsp. repandum at its western and eastern distribution limits. At one small site on Corsica, a population of C. repandum may have introgressed with relictual populations of C. balearicum. These divergence patterns illustrate how a phylogenetic perspective can be used to better understand the evolution of endemism in the Mediterranean flora. Received February 19, 2001 Accepted August 22, 2001  相似文献   

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