• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.250-256
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• 2003

Lactic acid bacteria with amylolytic and acid producing activities can ferment starch directly to lactic acid thereby producing a monomer for the production of biodegradable poly lactic acid (PLA). In this study, the strain producing L-lactic acid from soluble starch was isolated from Nuruk. The isolated strain was identified as Enterococcus sp. through its morphological, cultural, biochemical characteristics as well as the 16S rDNA sequence analysis, and named Enterococcus sp. JA-27. Enterococcus sp. JA-27 produced exclusively L-lactic acid from soluble starch as a carbon source. The optimal conditions for the maximum production of L-lactic acid from Enterococcus sp. JA-27 were 30 C, pH 8, 1.5 % soluble starch as a substrate and 3.5 % tryptone as a nitrogen source, 0.1 % $K_2$$HPO_4$, 0.04 % $MgSO_4$. $7H_2$O, 0.014 % $MnSO_4$$.$4$H_2O$, 0.004% $FeSO_4$$.$$7H_2$O. Batch and fed batch culture were carried out and the former was more effective. L-Lactic acid production in the optimum medium was significantly increased in a 7 L jar fermenter, where the maximum L-lactic acid concentration was 3 g/L. For the purification of lactic acid in fermented broth, two stage ionexchange column chromatographies were employed and finally identified by HPLC.

• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.378-383
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• 2016

The glasswort is an edible halophyte demonstrating various physiological effects including anti-inflammatory activity. In the present study, the effects of glasswort extracts on inflammatory events and interactions of THP-1 monocytes with intestinal epithelial cells were investigated. Five solvent fractions, including the ethylether fraction (Fr.E), were prepared from a 70% methanol extract of glasswort. THP-1 monocytes underwent differentiation by phorbol 12-myristate 13-acetate treatment and were then activated by lipopolysaccharide (LPS), which induced cyclooxygenase (COX)-2 expression. None of the glasswort fractions tested alone induced COX-2 in differentiated THP-1 cells. Fr.E, however, enhanced LPS-induced COX-2 expression in differentiated THP-1 cells. Culture media of THP-1 cells treated with each fraction stimulated the growth of normal intestinal INT-407 cells more prominently than that of HT-29 colon cancer cells. COX-2 expression in HT-29 cells was inhibited when the cells were exposed to the THP-1 culture medium treated with Fr.E. Thus, glasswort could modulate the interaction between immune cells and intestinal cells.

• Korean Chemical Engineering Research
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• v.48 no.3
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• pp.342-349
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• 2010

Lactic acid is widely used in the food, chemical and pharmaceutical industries, and there is an increasing demand for lactic acid as the raw material of poly lactic acid(PLA), which is a biodegradable polymer. Lactic acid production has been changing over from production by synthesis to production by fermentation, since the fermentation process is more nature friendly and economic. However, the fermentation method generates excess water and impurities with high boilers. The presence of high boilers and non volatility of lactic acid makes the separation of lactic acid very difficult job. Also, the purification-separation process requires the many investment costs and energy costs. Reactive distillation concept was also introduced for the process, giving higher selectivity and yield compared to the convention method. We introduce a new highly integrated process, reactive diving wall column, to reduce the capital and energy cost for producing a pure lactic acid. The reactive dividing wall column combines reactive distillation and dividing wall column. We compared capital and energy consumption required for the purification of lactic acid the between the proposed design structures. And we examined the effect of major process variables on the process performance and determined optimal process.

• Food Science and Preservation
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• v.19 no.1
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• pp.67-73
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• 2012

This study was carried out to investigate the packaging status of the $Agaricus$ $bisporus$ mushrooms and the benefits of storing them after precooling to improve their distribution system using small packages. The packaging status of the $Agaricus$ $bisporus$ mushrooms was surveyed at a farm, a department store, a wholesale market, and a supermarket from May to September 2011. The packaging materials that were used were PS, carton, PP, LDPE, PLA, and PVC. The harvested $Agaricus$ $bisporus$ mushrooms were precooled at $4^{\circ}C$ for three hours and were then stored at $20^{\circ}C$ for three days. The weight loss rate of the precooled sample was slightly lower than that of the unprecooled sample; conversely, the L value of the precooled sample was higher than that of the unprecooled sample. The ${\Delta}E$ value was lowest in the precooled sample after packaging. The precooling process effectively prolonged the shelf life and enhanced the quality of the$Agaricus$ $bisporus$ mushrooms.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9177-9183
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• 2014

Polymorphisms of inflammation-related genes have been found to be associated with non-Hodgkin lymphoma (NHL) or some of its subtypes, but only a few relevant data have been reported in China. In this study, the Snapshot method was used to assess genetic variation; a total of 14 single nucleotide polymorphisms (SNPs) for 6 inflammatory factors in 157 NHL cases (64 Uygur ethnic subjects, 93 Han Chinese) and 435 controls (231 Uygur and 204 Han Chinese) were studied from the Xinjiang province of China. Haplotype distribution was estimated using PHASE 2.3 software. Statistical differences in the genotype and haplotype frequencies between case and control groups were also considered and estimated. For the Han population, the geneotype distributions for TNF-${\alpha}rs1800629$, TNF-${\alpha}rs1800630$, IL-6 rs1800795, IL-6 rs1800797, NF-KB1 rs1585215 and TLR-4 rs4986790 showed significant differences between the case and control groups (p<0.05). The TNF-${\alpha}$ gene frequencies of ACG and CCA haplotypes in the cases were higher than in the controls (OR=2.45, 95% CI: 1.55-3.89, p=0.0002, OR=2.53, 95% CI: 1.10-5.80, p=0.029, respectively), and the same findings were detected for TNF-${\beta}$ gene CA haplotype (OR=1.87, 95% CI: 1.21-2.90, p=0.0054). However, for the Uygur population, no such significant differences were detected within the gene-type distribution of the 14 SNPs. The TNF-${\alpha}$ gene frequency of the CCA haplotype between the two groups (OR=1.98, 95% CI: 1.11-3.51, p=0.021) revealed a statistically significant difference. Our results showed that polymorphic variations of inflammation-related genes could be important to the NHL etiology of the Han population, and that these may only have limited influence on the Uygur population.

• Strategy21
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• s.38
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• pp.250-286
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• 2015

The main purpose of this article is to provide an understanding on current maritime issues in the Northeast Asia, and thereby help formulating the right strategy for our national security. The article summarizes core arguments in the recently published 『The 21^st Century Maritime Strategies in the Northeast Asia: Dilemma between Competition and Cooperation』. It will help readers to comprehend historical backgrounds as well as recent updates related to maritime issues and strategies in the region. Also, readers may find guidance to conceive their own maritime strategies for the Republic of Korea. Currently, the U.S. is shifting its focus from Atlantic to Pacific, and increasing its naval presence in Asia-Pacific region. Meanwhile, the 21^st century China views the maritime interests as the top priority in its national security and prosperity. PLA Navy's offensive maritime strategies and naval building such as aircraft carriers and nuclear submarines are unprecedented. Japan is another naval power in the region. During the Cold War JMSDF faithfully fulfilled the mission of deterring Soviet navy, and now it is doing its job against China. Lastly, Putin has been emphasizing to build the strong Russia since 2000, and putting further efforts to reinforce current naval capabilities of Pacific Fleet. The keyword in the naval and maritime relations among these powers can be summarized with "competition and cooperation." The recent security developments in the South China Sea(SCS) clearly represent each state's strategic motivations and movements. China shows clear and strong intention to nationalize the islands in SCS by building artificial facilities - possibly military purpose. Obviously, the U.S. strongly opposes China by insisting the freedom of navigation(FON) in international waters as recent USS-Lassen's FON operation indicate. The conflict between China and the U.S. surrounding the SCS seems to be heading towards climax as Russia and Japan are searching for their own national interests within the conflict. Also, the neighboring small and middle powers are calculating their own economic and security interests. This is no exception for us in establishing timely strategies to maximize our own national security. Hopefully, this article leads the readers to the right direction.

• Journal of the Korean Applied Science and Technology
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• v.16 no.3
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• pp.263-271
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• 1999

We checked the presence of phospholipase $A_2(PLA)_2$ which could split the ester bond at the position 2 in the glycerol backbone of glycerophospholipids, in the cells of hyperthermophiles of Pyrococcus horikoshii and Sulfolobus acidocaldarius. The results obtained are as follows; (1). Pyrococcus horikoshii cells were grown in obligate anaerobic conditions at $95^{\circ}C$ and they needed sulfur as energy source instead of oxygen, while Sulfolobus acidocaldarius species grew well in the aerobic medium (pH 2.5) containing yeast and sucrose at $75^{\circ}C$. (2). Pyrococcus horikoshii cells produced phospholipase $A_2$ in the cell culture media although this species did not show lipase activity at least in the pH range of 1.5 ${\sim}$ 3.5. Sulfolobus acidocaldarius cells produced lipase hydrolyzing triacylglycerols such as triolein, but did not split any kind of phospholipids used as substates. (3). The compound of 1-decanoyl-2-(p-nitrophenylglutaryl) phosphatidylcholine was not suitable for a substrate in this experiment, though frequently used as a subtrate for checking presence of phospholipase $A_2$, for its decomposi-tion in this experiment. The L-${\alpha}$-phosphatidylcholine-${\beta}$-[N-7-nitrobenz-2-oxa-1, 3-diazol]aminohexanoyl-${\gamma}$-hexadecanoyl labelled with a fluorescent material, did not show any migration of acyl chains in the molecule during the reaction with phospholipase $A_2$ under a hot condition. (4). Phospholipase $A_2$ in the cells of Pyrococcus horikoshii, showed the optimum activity at $pH6.7{\sim}7.2$ and $95{\sim}105^{\circ}C$, respectively, and was activated by addition of calcium chloride solution. Andthe phospholipase $A_2$ specifically hydrolyzed glycero-phospholipids such as phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl serine and phosphatidyl inositol, but could not split phospholipid containing ether bonds in the molecule such as DL -${\alpha}$-phosphatidylcholine-${\beta}$-palmitoyl-${\gamma}$-O-hexadecyl, DL-${\alpha}$-phosphati- dylcholine-${\beta}$- oleoyl-${\gamma}$-O-hexadecyl, DL-phosphatidylcholine-dihexadecyl.

• BMB Reports
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• v.46 no.6
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• pp.316-321
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• 2013

Gastric cancer remains the main cause of cancer death all around the world, and upregulated activation of the nonreceptor tyrosine kinase c-SRC (SRC) is a key player in the development. In this study, we found that expression of Src is also increased in clinical gastric cancer samples, with the protein level increased more significantly than that at the RNA level. Further study revealed that miR34a and miR203, two tumor suppressive miRNAs, inversely correlate with the expression of Src. Restoration of miR34a and miR203 decreased Src expression in gastric cancer cell lines, which in turn inhibited cell growth and cell migration. In summary, our study here revealed that posttranscriptional regulation of Src contributes to the deregulated cell growth and metastasis in gastric cancer, and targeting Src by miR34a or miR203 mimics would be a promising strategy in therapy.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.4
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• pp.425-434
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• 1997

Many reports represent that angiotensin II (ANG II) caused a dose dependent biphasic effects on fluid transport in the proximal tubule. However, respective roles of different signaling pathways in mediating these effects remain unsettled. The aim of the present study was to examine signaling pathways at high doses of ANG II on the $Na^+$ uptake of primary cultured rabbit renal proximal tubule cells(PTCs) in hormonally defined serum-free medium. High concentrations of ANG II $(>10^{-9}\;M)$ inhibited $Na^+$ uptake and increased $[Ca^{2+}]_i\;level$ in the PTCs. However, low concentrations of $(<10^{-11}\;ANG\;II)$ stimulated $Na^+$ uptake and did not affect $[Ca^{2+}]_i\;level$. 8-(N, N-diethylamino)-octyl-3,3,5- trimethoxybenzoate (TMB-8), ethylene glycol-bis$({/beta}-amino\;ethyl ether)-N,N,N'$, N'-tetra acetic acid (EGTA), and nifedifine partially blocked the inhibitory effects of ANG II on $Na^+$ uptake. When ANG II and bradykinin (BK) were treated together, $Na^+$ uptake was further reduced $(88.47{\pm}1.98%\;of\;that\;of\;ANG\;II,\;81.85{\pm}1.84%\;of\;that\;of\;BK)$. In addition, W-7 and KN-62 blocked the ANG II-induced inhibition of $Na^+$ uptake. Arachidonic acid reduced $Na^+$ uptake in a dose-dependent manner. When ANG II and arachidonic acid were treated together, inhibitory effects on $Na^+$ uptake significantly exhibited greater reduction than that of each group, respectively. When PTCs were treated by mepacrine $(10^{-6}\;M)$ and AACOCF3 $(10^{-5}\;M)$ for 1 hr before the addition of $(<10^{-9}\;ANG\;II)$, the inhibitory effect of ANG II was reversed. In addition, econazole $(>10^{-6}\;M)$ blocked ANG II-induced inhibition of $Na^+$ uptake. In conclusion, the $[Ca^{2+}]_i$ (calcium-calmodulin-dependent kinase) and phospholipase $A_2\;(PLA_2)$ metabolites are involved in the inhibitory effects of ANG II on $Na^+$ uptake in the PTCs.

• Journal of the Korean Society of Radiology
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• v.14 no.1
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• pp.61-68
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• 2020

The purpose of this study is to investigate the correlation of blooming artifacts according to dilution ratio of contrast agent on CT angiography images. A total of 10 sets were prepared by differently setting the ratio of contrast media and saline in a ball phantom made by a 3D printer. CT scan images were obtained and reconstructed by MIP and MPR techniques to obtain axial, sagittal and coronal images, respectively. After, the diameter of the ball phantom of the image obtained after the test was measured each 30 times, a total 1800 times. As a result, the dilution of 20:80 in the coronal plane was the smallest (p<0.05). Similarly, when dilute to 20:80 in the sagittal plane of MIP, it was the smallest as 20.39 ± 0.08 mm (p<0.05). Correlation analysis between dilution ratio and measurement size confirmed strong negative correlations in all reconstructed images (p<0.05). In conclusion, the higher the dilution ratio of the contrast agent, the more difficult it is to measure actual blood vessel measurement. Therefore, this study may provide basic data in future studies on actual measurement.