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61.
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
62.
Y. J. Cho S. Y. Kim J. Kim E. K. Choe S. I. Kim H. J. Shin 《Biotechnology and Bioprocess Engineering》2006,11(3):230-234
In this study, we describe a one-step chemoenzymatic reaction for the production of natural blue pigments, in which the geniposide
from Gardenia extracts is transformed by glycosidases to genipin. Genipin is then allowed to react with amino acids, thereby
generating a natural blue pigment. The β-glycosidases, most notably isolase (a variant of β-glucanase), recombinant β-glucosidase,
Cellulase T, and amylases, were shown to hydrolyze geniposide to produce the desired pigments, whereas the α-glycosidases
did not. Among the 20 tested amino acids, glycine and tyrosine were associated with the highest dye production yields. The
optimal molar ratio of geniposide to glycine, two reactants relevant to pigment production, was unity. The natural blue pigments
produced in this study were used to dye cotton, silk, and wool. The color yields of the pigments were determined to be significantly
higher than those of other natural dyes. Furthermore, the color fastness properties of these dyes were fairly good, even in
the absence of mordant. 相似文献
63.
Sung-Jin Cho Dae-Hee Lee Hyuk-Jae Kwon Chi Hyun Ahn Soon Cheol Park Kil-Sang Shin 《Development genes and evolution》2006,216(6):353-351
An echiuroid species, Urechis unicinctus, was surveyed for Hox genes using polymerase chain reaction with homeobox-specific degenerate primers. We identified nine distinct homeodomain-containing gene fragments. These nine fragments were classified by comparative analysis. This analysis revealed that this echiuroid possessed at least three Hox genes from the anterior group, five from the central group, and one from the posterior group.Sung-Jin and Dae-Hee Lee contributed equally to this work.An erratum to this article can be found at 相似文献
64.
Antifungal effects of the volatile oils from Allium plants against Trichophyton species and synergism of the oils with ketoconazole 总被引:2,自引:0,他引:2
In an attempt to develop stable and safe antifungal agents from natural products (daily foodstuffs in particular), the activities of essential oils from Allium sativum for. pekinense, A. cepa, and A. fistulosum against three Trichophyton species responsible for severe mycoses in humans were investigated and compared with activity of allicin in this study. The fungistatic activities of Allium oils were evaluated by the broth dilution method and disk diffusion assay. The combined effects of Allium oils with ketoconazole were tested by the checkerboard titer test. Among the tested oils, A. sativum for. pekinense oil exhibited the strongest inhibition of growth of T. rubrum, T. erinacei, and T. soudanense with MICs (minimum inhibiting concentrations) of 64microg/ml, while the activities of A. cepa and A. fistulosum were relatively mild. The inhibiting activities of the oils on Sabouraud agar plates were dose dependent against Trichophyton species. Additionally, these oils showed significant synergistic antifungal activity when combined with ketoconazole in the checkerboard titer test and disk diffusion test. 相似文献
65.
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
66.
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
67.
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
68.
Uhram Song Minjoo Shin Gisuk Lee Jinkyu Roh Younghun Kim Eun Ju Lee 《Biological trace element research》2013,155(1):93-103
Titanium dioxide nanoparticles (nano-TiO2) are manufactured and used worldwide in large quantities. However, phytotoxicity research on nano-TiO2 has yielded confusing results, ranging from strong toxicity to positive effects. Therefore, in this research, the effects of nano-TiO2 on the germination and root elongation of seed and seedlings were studied. Additionally, the uptake and physiological responses of mature plants were investigated. Physical chemistry data were analyzed to assess the availability of nano-TiO2. Finally, a hydroponic system designed to overcome nano-TiO2 precipitation was used to reproduce the environmental conditions of actual fields. Nano-TiO2 did not have any effect on seed germination or on most of the plant species tested. Nano-TiO2 had positive effects on root elongation in some species. No physiological differences in enzyme activities or chlorophyll content were detected, even though the plants absorbed nano-TiO2. Physical chemistry data showed that nano-TiO2 agglomerated rapidly and formed particles with much bigger hydrodynamic diameters, even in distilled water and especially in a hydroponic system. Furthermore, agglomerated nano-TiO2 formed precipitates; this would be more severe in an actual field. Consequently, nano-TiO2 would not be also readily available to plants and would not cause any significant effects on plants. Our results and other reports suggest that titanium itself is not phytotoxic, even though plants absorb titanium. In conclusion, nano-TiO2 is not toxic to the three plant species, in vitro or in situ. 相似文献
69.
Yu Zhang Yair Eliav Seung-uon Shin Taylor H. Schreiber Eckhard R. Podack Tamar Tadmor Joseph D. Rosenblatt 《Cancer immunology, immunotherapy : CII》2013,62(1):87-99
The mechanisms by which B lymphocytes inhibit anti-tumor immunity remain poorly understood. Murine EMT-6 mammary tumors grow readily in immune competent mice (BALB/c), but poorly in B-cell-deficient μ?/? BALB/c mice (BCDM). T regulatory cell (Treg) expansion and function were impaired in BCDM compared with BALB/c. In this study, we compared tumor growth, Treg cell proliferation, tumor lymphocyte infiltration and cytolytic T cell activity in BALB/c, BCDM and BCDM partially reconstituted with B cells by adoptive transfer (BCDM+B). Partial reconstitution of BCDM with adoptively transferred B cells restored EMT-6 tumor growth, which was independent of IL-10 secretion by B cells. Instead, high frequencies of intratumoral B cells were associated with increased recruitment and proliferation of Treg cells within the tumor microenvironment. The B-cell-dependent accumulation of Treg within the tumor microenvironment was associated with reduced tumor infiltration by CD49+ NK and CD8+ T cells and reduced cytotoxic T cell activity against EMT-6 targets. Our studies indicate that tumor-dependent immunosuppression of T-cell-mediated anti-tumor immunity is coordinated within the tumor microenvironment by B-cell-dependent cross talk with Treg cells, which does not require production of IL-10 by B cells. 相似文献
70.
Pitna Kim Jin Hee Park Chang Soon Choi Inah Choi So Hyun Joo Min Kyoung Kim Soo Young Kim Ki Chan Kim Seung Hwa Park Kyoung Ja Kwon Jongmin Lee Seol-Heui Han Jong Hoon Ryu Jae Hoon Cheong Jung Yeol Han Ki Narm Ko Chan Young Shin 《Neurochemical research》2013,38(3):620-631
Prenatal exposure to alcohol has consistently been associated with adverse effects on neurodevelopment, which is collectively called fetal alcohol spectrum disorder (FASD). Increasing evidence suggest that prenatal exposure to alcohol increases the risk of developing attention deficit/hyperactivity disorder-like behavior in human. In this study, we investigated the behavioral effects of prenatal exposure to EtOH in offspring mice and rats focusing on hyperactivity and impulsivity. We also examined changes in dopamine transporter and MeCP2 expression, which may underlie as a key neurobiological and epigenetic determinant in FASD and hyperactive, inattentive and impulsive behaviors. Mouse or rat offspring born from dam exposed to alcohol during pregnancy (EtOH group) showed hyper locomotive activity, attention deficit and impulsivity. EtOH group also showed increased dopamine transporter and norepinephrine transporter level compared to control group in the prefrontal cortex and striatum. Prenatal exposure to EtOH also significantly decreased the expression of MeCP2 in both prefrontal cortex and striatum. These results suggest that prenatal exposure to EtOH induces hyperactive, inattentive and impulsive behaviors in rodent offspring that might be related to global epigenetic changes as well as aberration in catecholamine neurotransmitter transporter system. 相似文献