• Applied Biological Chemistry
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• v.39 no.6
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• pp.430-436
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• 1996

The induction by xylose and repression by glucose of xylose isomerase(XI) were investigated to elucidate the regulation for production of XI in Escherichia coli. Regulation for expression of xyIA gene which codes XI is under control of xylR which is a regulatory gene for xylose catabolism. When xyIR gene was resided in chromosome, the inductions of XI by the addition of 0.4% xylose were increased to 1.9 and 1.7-fold in case of locating on multicopy(pEX202/DH77) and low copy Plasmid(pEX102/DH77), respectively, as compared with that of xylA gene which was resided in chromosome(JM109). xyIR gene product derived from xyIR gene on chromosome might react to xylA gene on the plasmid as same as xylA gene on chromosome. In JM109 and xylA transformant; pEX202/DH77 and pEX102/DH77, the inductions of XI were completely repressed by the addition of 0.2% glucose and these catabolite repressions were derepressed by the addition of 1 mM cAMP In comparison with the addition of 0.4% xylose only for the induction XI was inductively produced 1.7 to 2-fold with the addition of xylose plus 1 mM cAMP in DM minimal media. pEX13/TP2010, xylA transformant of the deficient mutant($xyl^-,\;cya^-$; TP2010) of XI and cAMP production, did not induce XI by the addition of xylose only but induced in case of simultaneous addition of xylose and cAMP. These results show that cAMP and xylose are the indispensable effectors for the induction and derepression of Xl in E. coli.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.4
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• pp.733-742
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• 2000

Fundamental materialistic characterization and adsorption/neutralization behavior of waste egg shell for heavy metal ion have been studied for its application to wastewater treatment. To investigate the structural change and thermal decomposition characteristics of egg shell. X-ray diffraction and FT-IR analysis were conducted for egg shell treated at $105^{\circ}C$ and $700^{\circ}C$, respectively. For the result of FT-IR analysis, the sample treated at $700^{\circ}C$ showed a reduced C-O absorption band compared with that of egg shell treated at $105^{\circ}C$, which may be due to the $CO_2$ release. Unlike to the result of FT-IR analysis, the XRD patterns of egg shell were almost similar for the cases of $105^{\circ}C$ and $700^{\circ}C$ treatment. however, characteristic diffraction pattern of CaO was observed for $850^{\circ}C$ treatment, at which $CaCO_3$ is known to be completely converted to CaO. TGA/DTA analysis showed a slow decline in weight loss up to $600^{\circ}C$ and, for $600{\sim}800^{\circ}C$ range, the weight loss became drastic by reason of $CO_2$ discharge, which was accompanied by an appearance of major endothermic peak. The ratio of practical breakthrough time to ideal one, total transfer unit, and mass transfer coefficient were observed to be increased as the adsorption was progressed in a multiple-column fixed-bed reactor using egg shell as an adsorbent, which signified the distribution effect of mass transfer for continuous adsorption reaction. The neutralization effect of egg shell for several types of acidic wastewater made of different mineral acids was not much different from each other except for the case of $H_2SO_4$, for which the neutralization reaction was thought to be retarded by the formation of gypsum.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.8
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• pp.554-563
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• 2013

The purpose of this study is to evaluate the possibility of nutrient release at up and downstream of Kangchun weir, upstream of Yuju and Ipo weir in Namhan River. For this survey, we measured basic characteristics of the sediments (water content, ignition loss, TOC, TP, SRP, TN, phosphorus fractionation) and conducted nutrients release experiments under both aerobic and anaerobic condition. The overlying water from the sediment-water column was analyzed for nutrients (i.e. TP, $PO_4$-P, TN, $NO_3$-N, $NH_3$-N) everyday for 18days. Result of soil texture experiment showed that sediments are Sand. SRP concentration before the release experiment was different with the value after the release experiment. According to this result, we can find that there were more activated release processes in anaerobic condition. $PO_4$-P increased from 1 to 8 days and remained at the maximum value (7~8 days) afterward. The rapidly increase of $PO_4$-P was observed from 1 to 2~3 days whereas the TP continuously increase from 1 to 18 days. The $PO_4$-P release rate calculated by up to 7~8 days data highly correlated with initial SRP concentration with $R^2$=0.8502. $NO_3$-N release rate appears constantly decreasing trend as -5.7~-3.08 $mg/m^2{\cdot}day$, otherwise the $NH_3$-N release rate, by-product of a organic matter decomposition using nitrate as electron acceptor, was 0.57~2.41 $mg/m^2{\cdot}day$. Substantial portion in TN can be induced by organic nitrogen which originated from the tributary passing through non-point pollutant source. Compared with other similar researches, phosphorus and nitrogen release rates obtained in this study can be considered as relatively low values. Since this study targeted the sediments accumulated by one time of flooding season, there are limitation to generalize theses results. Therefore, it is necessary to consistently monitor and investigate the accumulation of nutrients in the sediment for understanding the effect of weir construction on the overlying water quality.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.357-368
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• 1996

To utilize the ascidian tunic as a natural pigment and dietary sources for rainbow trout (Oncorhynchus mykiss), juvenile were fed on experimental diets containing enzymatic hydrolysates of ascidian tunic treated with three commercial mined enzymes (ultrazyme, cellulase, viscozyme) for 12 weeks. From the results of feeding experiment, similar growth rate was checked in the enzymatic hydrolysis group compared with control, and those were a higher than of ascidian tunic powder group. The total acetone extractable pigment in muscle of the enzymatic hydrolysates group was lower than that of the ascidian extracts group and carophyll pink group until 8 weeks, but the level of those pigment of the enzymatic hydrolysates was similar to the ascidian extracts and carophyll pink group after 12 weeks. The lipid content was increased with the pigment concentration in the all experimental group. But the ascidian tunic pigment did not influence on the composition of the fatty acids in the muscle and liver. From the consideration of results for pigmentation, the enzymatic hydrolysates of ascidian tunic were suitable for both a natural pigment and dietary protein and carbohydrates sources as a substitute synthetic pigment for aquaculture use.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.3
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• pp.37-48
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• 2019

This study, which starting from Yangyang Jukdo's topography formation and questioning revealed in landscape guide and landscape commentary board, is to sort out the characteristics of Jukdo natural landscape through literature research, field observation research and stakeholder interview as part of the proper recognition of Jokdo landscape and search for landscape resources, and pursued a review of nominations and criticism. The results of this study are summarized as follows. Yangyang Jukdo is an island named because it was full of blue bamboo. From before the first half of the 14th Century. to the middle of the 18th Century., there was a Gwanlan-pavilion to see the sea and the bamboo in the west. The time when the original island, the Jukdo, have been a land-tied island connected with the land by the tombolo formed by the erosion of the sand. It is located at the end of the 14th Century. and before the middle of the 18th Century. In Jukdo, colorful weathered terrains, coastal terrain, and structural terrain formed by long-time weathering are found. Among them, the type of weathering, the tafoni style and the gnamma style are the scenic landscapes with the key stories of legend and poetry that are brought to Jukdo. In addition, there are seven kinds of letters caved in the rocks in Jukdo. The rocks found on the coast, basketball cannons, shrines, and sutras are seen as shrouds based on a Taoist hermit motifs and style. In addition, it can be interred from the photography of "jeongssisejeog" that the souvenir of Jukdo was the family of Chogyejeong of mid 18th Century. In terms of observational geography and poetry, Jukdo has been handed down a great deal of missionary color with key motifs such as 'Jukdo-seongoo', 'Jukdo-Dolgooyoo', or 'Stone mortar of Taoist hermit' It is proved that the pearl which is called 'The stone of the Taoist hermit' is a porthole formed in a separate space rather than the topography of the geomorphology in terms of shape, size and function. Currently named Shun-tang is a product of the ridiculous 'naming' of interest. The present landscape guide and commentary is not only incompatible with the place of Jukdo, but also does not match the traditional cultural landscape. Future scenery information such as guide signs and commentary boards should be improved in the direction of positively highlighting the stories and motifs related to the present that are present in order to enhance the landscape identity of Yangyang Jukdo.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.134-141
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• 2005

To characterize genotypic and phenotypic traits of Staphylococcus aureus isolates (n = 86) from lettuces and raw milk, major virulence-associated genes and antibiotic susceptibility were detected using PCR-based methods and disk diffusion method, respectively. All isolates possessed coagulase gene and showed five polymorphism types [500 bp (2.4%), 580 bp (17.4%), 660 bp (61.6%), 740 bp (17.4%), and 820 bp (1.2%)] due to variable numbers of tandem repeats present within the gene. Two or three different loci of hemolysin gene family were dominant in isolates, 47 of which (55%) possessed combination of hla/hld/hlg-2 genes as the most prevalent types. Among enterotoxin-encoding genes, sea was detected from 32 isolates (37%), sed from 1 isolate (1%), and sea and sed genes were co-detected from 4 isolates (5%), whereas seb, sec, and tsst-1 genes were not detected. All isolates were susceptible to ciprofloxacin, trimethoprim/sulfamethoxazole, oxacillin, and vancomycin, 85 isolates (99%) to penicillin G, 54 isolates (63%) to chloramphenicol, 51 isolates (59%) to erythromycin, and 7 isolates (8%) to clindamycin. Among resistant isolates, seven displayed multiantibiotic-resistance against two different antibiotics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.573-580
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• 2005

Cholesterol $7\alpha-hydroxylase$ (CYP7A1) is the rate-limiting enzyme in the conversion of cholesterol to bile acids and plays a central role in regulating cholesterol homeostasis. We previously showed that a fermentable $\beta-glucan$ ingestion decreased plasma cholesterol levels due to fecal bile acid excretion elevation involved inincrease of cholesterol $7\alpha-hydroxylase$ mRNA expression and activity. It is proposed that short chain fatty acids (SCFA) produced by cecal and colonic fermentation of soluble fiber are associated with cholesterol-lowering effect of fiber. In the present study, we investigated whether CYP7A1 expression is up-regulated by short chain fatty acids or by hormones in cultured human hepatoma (HepG2) cells. Confluent HepG2 cell were incubated with acetate, propionate, or butyrate at 1 mM concentration for 24 hrs. Acetate as well as propionate increased to 1.8-fold expression of CYP7A1 mRNA than the control. Butyrate also increased 1.5-fold expression of CYP7A1 mRNA. Our data show for the first time that SCFA increase expression of CYP7A1 mRNA. Adding insulin, dexamethasone and triiodothyronine $(1\;{\mu}M)$ to HepG2 cell increased the expression of CYP7A1 mRNA to $150\%,\;173\%,\;141\%$, respectively. These results suggest that SCFA produced by cecal fermentation stimulate enteric nervous system, in which secreted some neuropeptides may be responsible for change in cholesterol and bile acid metabolism. These findings suggest that SCFA are involved in lowering plasma cholesterol levels due to the up-regulation of CYP7A1 and bile acid synthesis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.682-688
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• 2011

The purpose of this study was to measure the blood glucose level and glycemic index (GI) in response to persimmon (Diospyros kaki Thunb) syrup extracted from persimmon and extract of persimmon by-products. Major component analyses of persimmon syrup I (PSI, 95:5 mixture of purified persimmon syrup and non-purified persimmon syrup) and persimmon syrup II (PSII, 50:50 mixture ratio of purified persimmon syrup and non-purified persimmon syrup) were $0.3{\pm}0.1$ and $0.6{\pm}0.2$ mg/g for total polyphenolic compounds and $70.6{\pm}0.6$ and $66.6{\pm}1.6%$ for total carbohydrates, respectively. Blood glucose responses of PSI and PSII were determined using both normal ICR mice and streptozotocin (STZ)-induced diabetic male Sprague-Dawley (SD) rats. Further, oral glucose tolerance test (OGTT) was performed on diabetic rats to assess the effects of the experimental diets. Blood glucose response and OGTT showed that blood glucose levels were significantly lower in mice and diabetic rats fed PSI and PSII compared to those fed diets of sugar, maple syrup, or honey. The GIs of healthy volunteers in response to PSI and PSII were calculated to be 51.9 and 35.7, respectively. On the contrary, the GIs of healthy volunteers fed diets including sugar, maple syrup, or honey were 52.6, 20.0, and 93.0, respectively. These results suggest that persimmon syrup can be used for both the treatment of diabetics and healthy people due to its beneficial effects on blood glucose level.

• Journal of Korean Society of Forest Science
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• v.104 no.2
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• pp.187-192
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• 2015

Individuals in the population under a particular environmental condition influencing recurrently for a long time could locally adapted and local adaptation is of a fundamental importance in a breeding program, conservation activities of genetic resources or evolutionary biology. Plants at northern range limits have higher probability of expressing an adaptative genetic trait. The natural community at the northern range limit of Ilex cornuta (Chinese holly) in Buan, Jeollanam-do in Korea was composed of adults of 744 and seedlings of 211 (hereafter Community) and is designated as the Korean Natural Monument (No. 122) by the law. At two adjacent areas to Community, 85 (hereafter Plantation I) and 27 hollies (hereafter Plantation II) were planted respectively for preparations of the next generation. Eighty-five trees were sampled for genetic analysis in the three groups. Fifty-two (36%) of the total 143 amplicons were polymorphic from four AFLP primer combinations. A total of thirteen genotypes was identified and just one genotype was for 52 trees of Community. Seven and five genotypes were shown for Plantation I and II, respectively. There was no identical genotype between Community and Plantation (I or II) or between two plantation groups. Number of private loci was 2 for Community, 6 for Plantation I and 4 for Plantation II. We presumed their genetic backgrounds were quite different with one another and the plantation groups were made independently because they were different not only the genetic compositions but also their ages. Considering the genetic monomorphism by AFLP markers, observations of only male trees and asexual propagation as layerage or cuttage, the hollies in Community might be a genet by root suckering from a single male tree, not the results of selective removal of female trees for ornamental use in the past.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.4
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• pp.579-584
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• 2009

In this experiment, three different diets were produced to investigate the effects of Jeju native chicken eggs fed with citrus peel on the profiles of rats. The first diet did not contain any eggs (TS), the second diet contained 10% eggs and no citrus peels (T0), and the third diet contained 10% chicken egg with citrus peels (T1). These diets were provided to 11-week-old male rats for four weeks. The weight gain, feed intake and feed efficiency were not significantly different between the three treatment groups, TS, T0, and T1. The weight of the liver was significantly higher in T0 and T1 than TS (p<0.05), but the weights of the kidney and epididymal fat pad were not significantly different between the TS, T0, and T1 groups. The total lipid, phospholipid, triglycerides, total cholesterol and LDL cholesterol did not significantly difference among the TS, T0, and T1 groups. The HDL cholesterol and HDL cholesterol/ total cholesterol of T1 were the highest among the groups, and the atherogenic index of T1 was the lowest among the groups (p<0.05). The total protein of TS was significantly lower in T0 and T1, and the albumin of T1 was the highest among the groups (p<0.05). The albumin/globulin ratio of TS was significantly higher in T0 and T1, but the creatinine of T0 was significantly higher in T0 and T1 (p<0.05). The blood sugar and blood pigment were not significantly different between the TS, T0, and T1 groups. The $\gamma$-GTP of T1 was the lowest among the groups (p<0.05), but the ALT, AST and ALP did not show significant difference among the TS, T0, and T1 groups.