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291.
Reda A. I. Abou-Shanab Marwa M. El-Dalatony Mostafa M. EL-Sheekh Min-Kyu Ji El-Sayed Salama Akhil N. Kabra Byong-Hun Jeon 《Biotechnology and Bioprocess Engineering》2014,19(3):510-518
Coupling of advanced wastewater treatment with microalgae cultivation for low-cost lipid production was demonstrated in this study. The microalgal species Micractinium reisseri and Scenedesmus obliquus were isolated from municipal wastewater mixed with agricultural drainage. M. reisseri was selected based on the growth rate and cultivated in municipal wastewater (influent, secondary and tertiary effluents) which varied in nutrient concentration. M. reisseri showed an optimal specific growth rate (μopt) of 1.15, 1.04, and 1.01 1/day for the influent and the secondary and tertiary effluents, respectively. Secondary effluent supported the highest phosphorus removal (94%) and saturated fatty acid content (40%). The highest lipid content (40%), unsaturated fatty acid content, including monounsaturated and polyunsaturated fatty acids (66%), and nitrogen removal (80%) were observed for tertiary effluent. Fatty acids accumulating in the microalgal biomass (M. reisseri) were mainly composed of palmitic acid, oleic acid, linoleic acid, and a-linolenic acid. Cultivation of M. reisseri using municipal wastewater served a dual function of nutrient removal and biofuel feedstock generation. 相似文献
292.
S. Suresh Kumar Lalit Kumar Vikram Sahai Rani Gupta 《Journal of industrial microbiology & biotechnology》2009,36(3):427-432
An alkaline lipase from Trichosporon asahii MSR 54 was used to develop presoak formulation for removing oil stains at ambient temperature. The lipase was produced in
a reactor followed by concentration by ultrafiltration and then it was dried with starch. The biochemical characteristics
of enzyme showed that it was an alkaline lipase having pH activity in the range of pH 8.0–10.0 and temperature in the range
of 25–50°C. The present lipase was active >80% at 25°C. The lipase was cystein activated with fourfold enhancement in presence
of 5 mM cystein and likewise the activity was also stimulated in presence of papain hydrolysate which served as source of
cystein. The presoak formulation consisted of two components A and B, component A was enzyme additive and B was a mixture
of carbonate/bicarbonate source of alkali and papain hydrolysate as source of cystein. The results indicated that the presoaking
in enzyme formulation followed by detergent washing was a better strategy for stain removal than direct washing with detergent
in presence of lipase. Further, it was observed that 0.25% presoak component B in presence of 100 U enzyme component A (0.1 g)
was the best formulation in removing maximum stain from mustard oil/triolein soiled clothes as indicated by increase in reflectance
which was found equal to that of control cloth. The lipase action in presoaked formulation was clearly indicated by quantitated
fatty acid release and also the TLC results of wash water, where oil hydrolytic products were visible only in presence of
enzyme in the treatment. The wash performance carried at 25°C indicated that washing at 25°C was at par with that at 40°C
as indicated by similar reflectance of the washed cloth piece though qualitative fatty acid release was higher at 40°C. 相似文献
293.
294.
Praveen Balabaskaran Nina Natalya V. Dudkina Lesley A. Kane Jennifer E. van Eyk Egbert J. Boekema Michael W. Mather Akhil B. Vaidya 《PLoS biology》2010,8(7)
The F-type ATP synthase complex is a rotary nano-motor driven by proton motive force to synthesize ATP. Its F1 sector catalyzes ATP synthesis, whereas the Fo sector conducts the protons and provides a stator for the rotary action of the complex. Components of both F1 and Fo sectors are highly conserved across prokaryotes and eukaryotes. Therefore, it was a surprise that genes encoding the a and b subunits as well as other components of the Fo sector were undetectable in the sequenced genomes of a variety of apicomplexan parasites. While the parasitic existence of these organisms could explain the apparent incomplete nature of ATP synthase in Apicomplexa, genes for these essential components were absent even in Tetrahymena thermophila, a free-living ciliate belonging to a sister clade of Apicomplexa, which demonstrates robust oxidative phosphorylation. This observation raises the possibility that the entire clade of Alveolata may have invented novel means to operate ATP synthase complexes. To assess this remarkable possibility, we have carried out an investigation of the ATP synthase from T. thermophila. Blue native polyacrylamide gel electrophoresis (BN-PAGE) revealed the ATP synthase to be present as a large complex. Structural study based on single particle electron microscopy analysis suggested the complex to be a dimer with several unique structures including an unusually large domain on the intermembrane side of the ATP synthase and novel domains flanking the c subunit rings. The two monomers were in a parallel configuration rather than the angled configuration previously observed in other organisms. Proteomic analyses of well-resolved ATP synthase complexes from 2-D BN/BN-PAGE identified orthologs of seven canonical ATP synthase subunits, and at least 13 novel proteins that constitute subunits apparently limited to the ciliate lineage. A mitochondrially encoded protein, Ymf66, with predicted eight transmembrane domains could be a substitute for the subunit a of the Fo sector. The absence of genes encoding orthologs of the novel subunits even in apicomplexans suggests that the Tetrahymena ATP synthase, despite core similarities, is a unique enzyme exhibiting dramatic differences compared to the conventional complexes found in metazoan, fungal, and plant mitochondria, as well as in prokaryotes. These findings have significant implications for the origins and evolution of a central player in bioenergetics. 相似文献