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971.
Heaven MW Wild K Verheyen V Cruickshank A Watkins M Nash D 《Bioresource technology》2011,102(17):7727-7736
Bioreactors are often an integral part of dairy factory efforts to reduce the biological oxygen demand of their wastewater. In this study, infeed, mixed liquor and supernatant samples of an aerobic bioreactor used by a dairy factory in South-Eastern Australia were analyzed for nutrients and organic compounds using gas chromatography-mass spectrometry and physicochemical analyses. Despite different concentrations of organic inputs into the bioreactor, nutrients and trace organic compounds were reduced significantly (i.e. average concentration of trace organic compounds: infeed = 1681 μg/L; mixed liquor = 257 μg/L; supernatant = 23 μg/L). However, during one sampling period the bioreactor was adversely affected by the organic loading. Trace organic compounds in the samples were predominantly fatty acids associated with animal products. The analyses suggest that it is possible to trace a disruptive input (i.e. infeed with high organic carbon concentrations) into an aerobic bioreactor by measuring concentrations of fatty acids or ammonia. 相似文献
972.
Sheng J Kim HW Badalamenti JP Zhou C Sridharakrishnan S Krajmalnik-Brown R Rittmann BE Vannela R 《Bioresource technology》2011,102(24):11218-11225
Synechocystis sp. PCC6803 exhibited a high degree of variation in biomass and lipid production rates in response to temperature changes in a photobioreactor. Compared with an optimal temperature of 30-33°C, a higher temperature of 44°C and lower temperatures of 22°C and 18°C severely inhibited the specific growth rate (up to a 66% decrease), biomass production rate (up to a 71% decrease), nutrient utilization rates (up to a 77% decrease), and lipid production rate (up to a 80% decrease). Temperature stress triggered changes in the relative percentage of individual fatty acids (mainly for C16:0 and C18:3), and degree of unsaturation significantly changed: 0.87 at 30°C, 0.62 at 44°C, and 1.29 at 18°C. Although PCC6803 survived temperature stress and maintained its predominate position in the culture, it could not fully recover from long-term temperature stress. Thus, avoiding prolonged exposure to extreme temperature is crucial for using PCC6803 as feedstock for biofuel production. 相似文献
973.
The aim of this work was to obtain biodiesel from animal fats, an inedible feedstock. Three different types of fats were used to produce biodiesel; their main characteristic was high free fatty acid content. Animal fats were transesterified with acid catalyst and basic catalyst with and without pre-esterification. Biodiesel of 89.0 wt.% ester content was obtained by acid-transesterification (9 wt.% H2SO4, 6:1 methanol:fats molar ratio, 60 °C, 48 h). Pre-esterification conditions were studied for different fats and acid catalysts: 0.5 wt.% H2SO4 or 1.0 wt.% p-TsOH, 6:1 methanol:fats molar ratio, 65 °C and 4 h made it possible to obtain fats with acid value less than 0.5% FFA. Pre-treatment was effective for fats with different FFA content. Alkali transesterification of esterified fats resulted in a product with 97.3 wt.% ester content. Biodiesel quality was evaluated and most of properties were well within EN 14214. 相似文献
974.
In humans, thromboxane (TX) A2 signals through the TPα and TPβ isoforms of its G-protein coupled TXA2 receptor (TP) to mediate a host of (patho)physiologic responses. Herein, angio-associated migratory cell protein (AAMP) was identified as a novel interacting partner of both TPα and TPβ through an interaction dependent on common (residues 312-328) and unique (residues 366-392 of TPβ) sequences within their carboxyl-terminal (C)-tail domains. While the interaction was constitutive in mammalian cells, agonist-stimulation of TPα/TPβ led to a transient dissociation of AAMP from immune complexes which coincided with a transient redistribution of AAMP from its localization in an intracellular fibrous network. Although the GTPase RhoA is a downstream effector of both AAMP and the TPs, AAMP did not influence TP-mediated RhoA or vice versa. Small interfering RNA (siRNA)-mediated disruption of AAMP expression decreased migration of primary human coronary artery smooth muscle cells (1° hCoASMCs). Moreover, siRNA-disruption of AAMP significantly impaired 1° hCoASMC migration in the presence of the TXA2 mimetic U46619 but did not affect VEGF-mediated cell migration. Given their roles within the vasculature, the identification of a specific interaction between TPα/TPβ and AAMP is likely to have substantial functional implications for vascular pathologies in which they are both implicated. 相似文献
975.
Unperturbed mitosis is a prerequisite for the generation of two genetically identical daughter cells. Nucleolar-spindle associated protein (NuSAP) is an important mitotic regulator. The activity of NuSAP is essential for a variety of cellular events that occur during mitosis starting from spindle assembly to cytokinesis. In addition to playing crucial roles during mitosis, NuSAP has been in the spotlight recently due to different studies exhibiting its importance in embryogenesis and cancer. In this review, we have extensively mined the current literature and made connections between different studies involving NuSAP. Importantly, we have assembled data pertaining to NuSAP from several proteomic studies and analyzed it thoroughly. Our review focuses on the role of NuSAP in mitosis and cancer, and brings to light several unanswered questions regarding the regulation of NuSAP in mitosis and its role in carcinogenesis. 相似文献
976.
Revilla-López G Rodríguez-Ropero F Curcó D Torras J Isabel Calaza M Zanuy D Jiménez AI Cativiela C Nussinov R Alemán C 《Proteins》2011,79(6):1841-1852
Recently, we reported a database (Noncoded Amino acids Database; http://recerca.upc.edu/imem/index.htm) that was built to compile information about the intrinsic conformational preferences of nonproteinogenic residues determined by quantum mechanical calculations, as well as bibliographic information about their synthesis, physical and spectroscopic characterization, the experimentally established conformational propensities, and applications (Revilla-López et al., J Phys Chem B 2010;114:7413-7422). The database initially contained the information available for α-tetrasubstituted α-amino acids. In this work, we extend NCAD to three families of compounds, which can be used to engineer peptides and proteins incorporating modifications at the--NHCO--peptide bond. Such families are: N-substituted α-amino acids, thio-α-amino acids, and diamines and diacids used to build retropeptides. The conformational preferences of these compounds have been analyzed and described based on the information captured in the database. In addition, we provide an example of the utility of the database and of the compounds it compiles in protein and peptide engineering. Specifically, the symmetry of a sequence engineered to stabilize the 3(10)-helix with respect to the α-helix has been broken without perturbing significantly the secondary structure through targeted replacements using the information contained in the database. 相似文献
977.
Fobian YM Freskos JN Barta TE Bedell LJ Heintz R Kassab DJ Kiefer JR Mischke BV Molyneaux JM Mullins P Munie GE Becker DP 《Bioorganic & medicinal chemistry letters》2011,21(10):2823-2825
Continuing our interest in designing compounds preferentially potent and selective for MMP-13, we report on a series of hydroxamic acids with a flexible amide P1′ substituents. We identify an amide which spares both MMP-1 and -14, and shows >500 fold selectivity for MMP-13 versus MMP-2 and -8. 相似文献
978.
979.
对种植在我国不同区域、不同品种早实核桃的氨基酸质量分数进行了测定.结果表明氨基酸质量分数中新新2号最高为18.79%、其次为鲁光18.72%.人体必需氨基酸质量分数中鲁光最高为5.34%、其次是新新2号,为5.31%. 相似文献
980.
以3种不同的百合为原料,用水浸提法提取百合中游离氨基酸,对提取条件进行研究,通过正交试验确定最适宜提取条件(即:以7.5%乙酸为提取液,料液比1:35,70℃提取3 h).同时采用氨基酸分析仪测定3种百合的水提取液样品,共检出17种游离氨基酸(其中7种为必需氨基酸).结果表明,百合中的游离氨基酸以精氨酸为主体,占总游离... 相似文献