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91.
Sung-Euy Shin DuBok Choi Choon-Boem Lee Wol-Suk Cha 《Biotechnology and Bioprocess Engineering》2006,11(4):325-331
Various environmental conditions affecting total phosphorus removal from farm wastewater in a biofilm filter, process were
investigated using loess balls andChromobacterium LEE-38 at a pilot plant. WhenChromobacterium LEE-38 was used, the removal efficiency of total phosphorous was approximately 10- or 5-fold higher than that ofAcinetobacter CHA-2-14 orAcinetobacter CHA-4-5, respectively. When a loess ball of 11–14 mm manufactured at a 960°C calcining temperature was used, the removal
efficiency of total phosphorous was 90.0%. When 70% of the volume fraction was used, the maximum efficiency of total phosphorus
removal was 93.1%. Notably, when the initial pH was in the range of 6.0 to 8.0, the maximum removal efficiency of total phosphorus
was obtained after 30 days. When the operating temperature was in the range of 30 to 55°C, the maximum removal efficiencies
of total phosphorus, 95.6 to 94.6%, were obtained. On the other hand, at operating temperatures below 20°C or above 40°C,
the removal efficiency of total phosphorous decreased. Among the various processes, biofilm filter process A gave the highest
removal efficiency of 96.4%. Pilot tests of total phosphorus removal using farm wastewater from the biofilm filter process
A were carried out for 60 days under optimal condition. WhenAcinetobacters sp. Lee-11 was used, the average removal efficiency in thep-adsorption area was only 32.5%, and the removal efficiencies of chemical oxygen demand (COD) and biological oxygen demand
(BOD) were 56.7 and 62.5%, respectively. On the other hand, whenChromobacterium LEE-38 was used, the average removal efficiency was 95.1%, and the removal efficiencies of COD and BOD were 91.3 and 93.2%,
respectively.
The first two authors contributed equally to this work. 相似文献
92.
Jin Chuan Wu Hou Ran Low Yujun Leng Yvonne Chow Ruijiang Li MMR Talukder Won Jae Choi 《Biotechnology and Bioprocess Engineering》2006,11(3):211-214
ImmobilizedCandida antarctica lipase was used to catalyze the separation of ketoprofen into its components by means of esterification followed by the enzymatic
hydrolysis of the ester product. In this study, ketoprofen underwent esterification to ethanol in the presence of isooctane.
When the reaction was complete, 58.3% of the ketoprofen had been transformed into an ester. The ketoprofen remaining in solution
after the reation was complete consisted primarily of itsS-enantiomer (83.0%), while the 59.4% of the ketoprofen component of the ester consisted of itsR-enantiomer. We then subjected the ester product to enzymatic hydrolysis in the presence of the same enzyme and produced a
ketoprofen product rich in theR-enantiomer; 77% of this product consisted of theR-enantiomer when 50% of the ester had been hydrolyzed, and 90% of it consisted of theR-enantiomer when 30% of the ester had been hydrolyzed. By contrast, theR-enantiomer levels only reached approximately 42 and 65%, respectively, when 50 and 30% of the racemic ester was hydrolyzed
under the same conditions. 相似文献
93.
94.
95.
Dong W. Choi Young S. Do Corbin J. Zea Marcus T. McEllistrem Sung-W. Lee Jeremy D. Semrau Nicola L. Pohl Clint J. Kisting Lori L. Scardino Scott C. Hartsel Eric S. Boyd Gill G. Geesey Theran P. Riedel Peter H. Shafe Kim A. Kranski John R. Tritsch William E. Antholine Alan A. DiSpirito 《Journal of inorganic biochemistry》2006,100(12):2150
Methanobactin (mb) is a novel chromopeptide that appears to function as the extracellular component of a copper acquisition system in methanotrophic bacteria. To examine this potential physiological role, and to distinguish it from iron binding siderophores, the spectral (UV–visible absorption, circular dichroism, fluorescence, and X-ray photoelectron) and thermodynamic properties of metal binding by mb were examined. In the absence of Cu(II) or Cu(I), mb will bind Ag(I), Au(III), Co(II), Cd(II), Fe(III), Hg(II), Mn(II), Ni(II), Pb(II), U(VI), or Zn(II), but not Ba(II), Ca(II), La(II), Mg(II), and Sr(II). The results suggest metals such as Ag(I), Au(III), Hg(II), Pb(II) and possibly U(VI) are bound by a mechanism similar to Cu, whereas the coordination of Co(II), Cd(II), Fe(III), Mn(II), Ni(II) and Zn(II) by mb differs from Cu(II). Consistent with its role as a copper-binding compound or chalkophore, the binding constants of all the metals examined were less than those observed with Cu(II) and copper displaced other metals except Ag(I) and Au(III) bound to mb. However, the binding of different metals by mb suggests that methanotrophic activity also may play a role in either the solubilization or immobilization of many metals in situ. 相似文献
96.
Byung-Chul Choi Hang-Sik Shin Su-Yol Lee Tak Hur 《The International Journal of Life Cycle Assessment》2006,11(2):122-128
Background, Aims and Scope Telecommunication and information technology, dramatically emerged during the last decade, has generated environmental problems
by accelerating mass production, mass consumption, and mass disposal of personal computers (PCs) in Korea. In addition, it
has led the Korean new economy. The Korean government has encouraged researchers and industry to study the environmental impact,
adequate disposal treatment, and the reasonable recycling rate of an end-of-life personal computer. The main purpose of this
research is to investigate the life cycle environmental impact of PCs and to determine the desirable or feasible recycle rate
of an end-of-life PC. An LCA on a PC was performed based on different recycling scenario. Target audiences are new product
developers, designers, product recovery managers and environmental policy makers who are interested in the environmental impact
of PCs and recycling of end-of-life products.
Methods A target product is a Pentium IV personal computer made in Korea in 2001, excluding the monitor and peripheral equipment.
The procedure of the LCA followed the ISO14040 series. System boundary includes the entire life cycle of the product, including
pre-manufacturing (the electrical parts and components manufacturing), manufacturing, transportation, use, and disposal. The
LCI and impact assessment database for a PC was constructed using SIMAPRO version 4.0 software and LCI information was compiled
by site-specific data and the Korean national database. The LCA was performed on different recycling scenarios: one being
that of the current recycling rate of 46%, and the other being the ideal condition of a 100% recycling rate.
Results and Discussion Abiotic depletion, global warming, ecotoxicity, human toxicity, acidification, ozone layer depletion, photo-oxidant formation,
and eutrophication are adopted as the impact categories. The pre-manufacturing stage was a significant stage for all of the
environmental parameters, besides human toxicity potential. PC manufacturing consists of rather simple processes such as assembly
and packaging. For improving the environmental performance of PCs, environmental management approaches of design for the environment
and green procurement are recommended. The use stage had a significant potential due to the electricity consumption produced
by burning fossil fuel. The disposal stage's contribution to environmental impact was largest in human toxicity, and second
largest in ozone layer depletion potential. The PC recycling was shown to inhibit all environmental impacts with the exception
of the ozone depletion and ecotoxicity potential. The increase of light oil, nitric acid, sulfuric acid, and deoxidating agent
consumption during the recycling process contributes to the environmental impact of ozone and ecotoxicity parameters. Current
recovery and recycling technologies should be taken into account for enhancing the benefits of recycling. Anyway, the effectiveness
of recycling was highlighted by this study. PC recycling reduces the total environmental impact of the product. The PC recycling
is recommended to be raised up to at least 63% in order to reduce the environmental burdens of a PC in other life cycle stages.
Conclusion and Recommendation This study implies that design for the environment (DfE) in the product design stage and green procurement are recommended
for improving the entire environmental performance of electronic equipment such as PCs. The recycling of waste PCs clearly
reduces the environmental burden. There are, however, trade-offs among environmental parameters according to the PC recycling
rate. Current recycling methods are not effective in reducing ozone depletion and ecotoxicity environmental impact. The product
recovery is another key for efficient recycling. Efficient reverse logistics to collect and transport end-of-life PCs should
be taken into account to enhance recycling effects. There were several electrical parts not included in this assessment, due
to the unavailability of adequate data. Further studies with more detail and reliable inventories for electrical parts and
sub-components are recommended. Furthermore, costs of recycling should also be treated in further research. 相似文献
97.
Silkworm hemolymph (SH) has been reported to inhibit apoptosis in both insect and human cells, and increase the high-sialylation structure of recombinant glycoprotein in insect cells. This indicates that SH might increase glycosyltransferase activity. Therefore, this study examined the effect of SH on the activity of sialyltransferase, which catalyzes the sialylation of the glycoprotein. When 10 μg/mL of SH was added to the reaction mixture, almost complete sialylation was observed even under the reaction conditions where sialyltransferase-catalyzed sialylation rarely occurs. The effect of deproteinized SH (dSH) and the 30K protein, which is a major plasma protein in SH, was examined to determine which component in SH enhances sialylation. The 30K protein promoted sialylation, while the dSH did not. This suggests that SH and its 30K protein can be used as an additive to a medium for efficient glycosylation when mammalian cells are being cultured for the production of valuable biopharmaceuticals, many of which are glycoproteins. 相似文献
98.
Song Ah Choi Jong Won Yun Hee Sung Park Jang Won Choi 《Molecular biology reports》2013,40(2):1753-1765
The proteins in plasma perform many important functions in the body, and the protein profiles of the plasma vary under different physiological and pathological conditions. In an attempt to identify novel marker proteins for diabetes prognosis, we examined the effect of hypoglycemic dipeptide cyclo (His-Pro) (CHP) on the differential regulation of plasma proteins in streptozocin-induced diabetic rats and genetically-diabetic (ob/ob) mice. The orally-administrated CHP produced an excellent hypoglycemic effect in both animal models, lowering the average plasma glucose level by over 50 %. In the 2-DE analysis of the plasma, a total of 23 spots among 500 visualized spots were found to be differentially regulated, and they were identified by MALDI/TOF mass spectrometry. These proteins include the down-regulation of Apo E and the up-regulation of FGA, Apo A-I, Apo A-IV, and A1M in STZ-induced diabetic rats. Moreover, CHP significantly reduced the plasma protein levels of FGB, FGC, F12, C1QTNF5, and SPA3K, as well as increased the abundance of A1M, A2M, Apo E, and TTR in genetically-diabetic mice. In conclusion, alteration in the regulation of these proteins indicates that this treatment may be successful in overcoming the diabetic state. The present proteomic data can serve as the basis for the development of specific evidence-based interventions allowing for the prevention and treatment of diabetes. 相似文献
99.
Byung-Kook Choi Sang-Hee Jeong Joon-Hyung Cho Hyo-Sook Shin Seong-Wan Son Young-Keun Yeo Hwan-Goo Kang 《Mycotoxin Research》2013,29(3):185-192
Mice were exposed to deoxynivalenol (DON) via drinking water at a concentration of 2 mg/L for 36 days. On day 8 of treatment, inactivated porcine parvovirus vaccine (PPV) was injected intraperitoneally. The relative and absolute weight of the spleen was significantly decreased in the DON-treated group (DON). Antibody titers to parvovirus in serum were 47.9?±?2.4 in the vaccination group (Vac), but 15.2?±?6.5 in the group treated with DON and vaccine (DON?+?Vac). The IgA and IgG was not different in the DON, Vac an,d DON?+?Vac groups. IgM was significantly lower only in the DON?+?Vac group. However IgE was significantly increased in the Vac and DON?+?Vac group, but no change was observed between the Vac and DON?+?Vac groups. The concentrations of IL-2, IL-4, GM-CSF, MCP-1 and Rantes in serum, and IL-1α in mesenteric lymph node and MIP-1β in spleen were significantly increased by DON treatment compared to control. The concentrations of IL-2, IL-5, IL-6, IL-9, IL-12, IL-13 and Rantes in thymus, of IL-2 in spleen, and of IL-1α, IL-1β, IL-3, IL-5, IL-10, IL-17, G-CSF, GM-CSF and MCP-1 in mesenteric lymph nodes were significantly decreased in mice compared to those in the Vac group, while concentrations of IL-1α, IL-2, IL-9, IL-13,G-CSF, GM-CSF, IFN-γ, MCP-1, MIP-1α and TNF-α were significantly increased in serum compared to the Vac group. In conclusion, the results presented here indicate that exposure to DON at 2.0 mg/L via drinking water can disrupt the immune response in vaccinated mice by modulating cytokines and chemokines involved in their immune response to infectious disease. 相似文献
100.
This study was conducted to examine the psycho-emotional effects of repeated oral exposure to capsaicin, the principal active component of chili peppers. Each rat received 1 mL of 0.02% capsaicin into its oral cavity daily, and was subjected to behavioural tests following 10 daily administrations of capsaicin. Stereotypy counts and rostral grooming were significantly increased, and caudal grooming decreased, in capsaicin-treated rats during the ambulatory activity test. In elevated plus maze test, not only the time spent in open arms but also the percent arm entry into open arms was reduced in capsaicin-treated rats compared with control rats. In forced swim test, although swimming duration was decreased, struggling increased in the capsaicin group, immobility duration did not differ between the groups. Repeated oral capsaicin did not affect the basal levels of plasma corticosterone; however, the stress-induced elevation of plasma corticosterone was prolonged in capsaicin treated rats. Oral capsaicin exposure significantly increased c-Fos expression not only in the nucleus tractus of solitarius but also in the paraventricular nucleus. Results suggest that repeated oral exposure to capsaicin increases anxiety-like behaviours in rats, and dysfunction of the hypothalamic-pituitary-adrenal axis may play a role in its pathophysiology. 相似文献