• Journal of Sensor Science and Technology
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• v.20 no.6
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• pp.368-374
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• 2011

A microfluidic device for real-time monitoring of residual free chlorine and pH in water based on optical absorption is proposed. The device consists of a serpentine micromixer for mixing samples with a reagent, and a photodiode and light emitting diode(LED) for the detection of light absorbance at specific wavelengths, determined for specific reagent combinations. Spectral analyses of the samples mixed with N, N'-diethyl-p-phenylenediamine(DPD) reagent for chlorine determination and bromothymol blue(BTB) for pH measurement are performed, and the wavelengths providing the most useful linear changes in absorbance with chlorine concentration and pH are determined and used to select the combination of LED and photodiode wavelengths for each analyte. In tests using standard solutions, the device is shown to give highly reproducible results, demonstrating the feasibility of the device for the inexpensive and continuous monitoring of water quality parameters with very low reagent consumption.

• Korean Journal of Pharmacognosy
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• v.21 no.2
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• pp.148-152
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• 1990

Seven flavonol glycosides from the EtOAc fraction of Ginkgo biloba leaves were identified by high performance liquid chromatography. Separation by reversed phase chromatography on $Lichrosorb^{\circledR}$ RP-18 column was achieved by isocratic elution. The content of the major acylated flavonol glycoside, kaempferol 3-0-[$6'-O-{p}-coumaroyl-{\beta}-_D-glucosyl(1{\rightarrow}2)-{\alpha}-_L-rhamnoside$] was about 8.0% and 0.55% for EtOAc fraction and MeOH extract, respectively.

• The Korean Journal of Soil Zoology
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• v.6 no.1_2
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• pp.7-9
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• 2001

Six species of the phytoseiid mites were recorded from the pear field of Naju District in Korea: Amblyseius womersleyi, A. eharai, A. orientalis, A. makuwa, A. bakeri and Proprioseiopsis nemotoi. Of these, A. bakeri and p. nemotoi were previously unrecorded in this field, and genus Proprioseiopsis is recorded for the first time in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.3
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• pp.131-137
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• 2020

The present study investigated effects of antifungal and carboxylesterase inoculant on rumen fermentation with different rumen pH. Corn silage was treated without inoculant (CON) and with a mixed Lactobacillus brevis 5M2 and L. buchneri 6M1 (MIX). Rumen fluid was collected from two cannulated Hanwoo heifers before morning feeding (high rumen pH at 6.70) and 3 h after feeding (low rumen pH at 6.20). Dried corn silage was incubated in the rumen buffer (rumen fluid + anaerobic culture medium at 1:2 ratio) for 48 h at 39℃. Eight replications for each treatment were used along with two blanks. Both in a high and a low rumen pH, MIX silages presented higher (p<0.05) the immediately degradable fraction, the potentially degradable fraction, total degradable fraction, and total volatile fatty acid (VFA) than those of CON silages. Incubated corn silages in a low rumen pH presented lower (p<0.05) total degradable fraction, ammonia-N, total VFA (p=0.061), and other VFA profiles except acetate and propionate, than those in a high rumen pH. The present study concluded that application of antifungal and carboxylesterase inoculant on corn silage could improve degradation kinetics and fermentation indices in the rumen with high and low pH conditions.

• KSBB Journal
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• v.23 no.6
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• pp.519-524
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• 2008

Monacolin-K is a strong anti-hypercholesterolemic agent produced by Monascus sp. via polyketide pathway. High-yielding mutants of monacolin-K were developed through rational screening strategies adopted based on understanding of monacolin-K biosynthetic pathway. Through the experiments for investigating various amino acids as putative precursors for the monacolin-K biosynthesis, it was found that production level of monacolin-K was remarkably increased when optimum amount of cysteine was supplemented into the production medium. We suggested that these phenomena might be related to the special roles of SAM (S-adenosyl methionine), a putative methyl group donor in the biosynthetic pathway of monacolin-K, demonstrating close interrelationship between SAM-synthesizing primary metabolism and monacolin-K synthesizing secondary metabolism. Namely, increase in the intracellular amount of SAM derived from the putative precursor, cysteine which was extracellularly supplemented into the production medium might contribute to the significant enhancement in the monacolin-K biosynthetic capability of the highly mutated producers. On the basis of these assumptions derived from the above fermentation results, we decided to construct efficient expression vectors harboring SAM synthetase gene (metK) cloned from A. nidulans, with the hope that increased intracellular level of SAM could lead to further enhancement in the monacolin-K production through overcoming a rate-limiting step associated with monacolin-K biosynthesis. Hence, in order to overcome the plausible rate-limiting step associated with monacolin-K biosynthesis by increasing intracellular level of SAM, we transformed the producer mutants with an efficient expression vector harboring gpdA promoter of the producer microorganism, and metK gene. Notably, from the resulting various transformants, we were able to screen a very high-yielding transformant which showed approximately 3.3 fold higher monacolin-K productivity than the parallel nontransformed mutants in shake flask cultures performed under the identical fermentation conditions.

• Mycobiology
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• v.47 no.4
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• pp.441-448
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• 2019

Two new SAM-dependent methyltransferase encoding genes (fvsmt1 and fvsmt2) were identified from the genome of Flammulina velutipes. In order to make a comprehensive characterization of both genes, we performed in silico analysis of both genes and used qRT-PCR to reveal their expression patterns during the development of F. velutipes. There are 4 and 6 exons with total length of 693 and 978 bp in fvsmt2 and fvsmt1, respectively. The deduced proteins, i.e., FVSMT1 and FVSMT2 contained 325 and 230 amino acids with molecular weight 36297 and 24894 Da, respectively. Both proteins contained a SAM-dependent catalytic domain with signature motifs (I, p-I, II, and III) defining the SAM fold. SAM-dependent catalytic domain is located either in the middle or at the N-terminal of FVSMT2 and FVSMT1, respectively. Alignment and phylogenic analysis showed that FVSMT1 is a homolog to a protein-arginine omega-N-methyltransferase, while FVSMT2 is of cinnamoyl CoA O-methyltransferase type and predicted subcellular locations of these proteins are mitochondria and cytoplasm, respectively. qRT-PCR showed that fvsmt1 and fvsmt2 expression was regulated in different developmental stages. The maximum expression levels of fvsmt1 and fvsmt2 were observed in stipe elongation, while no difference was found in mycelium and pileus. These results positively demonstrate that both the methyltransferase encoding genes are involved in the stipe elongation of F. velutipes.

• Journal of Hospice and Palliative Care
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• v.10 no.1
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• pp.35-42
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• 2007

Purpose: Colorectal ranter is the 4th leading cause of cancer death in Korea and the prevalence is increasing continuously. This study was aimed to figure out the problems through the clinical consideration about terminal colorectal ranter patients who had died in hospice unit. Methods: We retrospectively reviewed the medical records in 78 patients with colorectal ranter who had admitted, received palliative care, and died in a hospice unit between April 2003 and November 2006. Results: The median age of patients was 59.6 years with 45 men (58%) and 24 women (42%). The median survival in hospice and palliative care was 36 days. The median hospitalization was 22 days. The most prevalent reason for admission was pain (38 patients, 49%), and the most common symptom was also pain (70 patients, 90%). Forty eight patients (62%) took analgesics before hospice referral. Twenty seven patients (65%) of 45 patients with intestinal obstruction have been performed palliative procedures. Median survival of patients with palliative procedure was higher than that of no palliative procedure group (47 days vs 19 days, P-value=0.005). Conclusion: The duration of hospice and palliative care was not enough to care the terminal colorectal cancer. Therefore, we suggest that proper education and information should be provided to physician, patients and their family members for effective hospice and palliative care.

• International Journal of Oral Biology
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• v.43 no.3
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• pp.141-146
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• 2018

Periodontitis is generally a chronic disorder characterized by breakdown of tooth-supporting tissues, producing dentition loss. Porphyromonas gingivalis (P. gingivalis), a Gramnegative anaerobic rod, is one of the major pathogens associated with periodontitis. Neutrophils are first line defense cells in the oral cavity that play a significant role in inflammatory response. Xylitol is a known anti-caries agent and has anti-inflammatory effects. In this study, we conducted experiments to evaluate anti-inflammatory effects of xylitol on P. gingivalis infected neutrophils for possible usage in prevention and treatment of periodontal infections. P. gingivalis was intraperitoneally injected and peritoneal lavage was collected for cytokine determination. For in vitro study, neutrophils were collected from mouse peritoneal cells after zymosan injection or bone marrow cells. Neutrophils were stimulated with live P. gingivalis and ELISA was used to determine the effect of xylitol on P. gingivalis induced cytokine production. $IL-1{\beta}$, IL-6, $TNF-{\alpha}$ concentration and neutrophil population in the peritoneal lavage was increased in P. gingivalis-infected mouse. Peritoneal cells infected with live P. gingivalis revealed significantly increased production of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ at multiplicity of infection of 10. Neutrophils from bone marrow and peritoneal lavage revealed increased production of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$. Xylitol significantly mitigated P. gingivalis induced cytokine production in neutrophils. Findings indicate that xylitol is an anti-inflammatory agent in neutrophils infected with live P. gingivalis, that suggests its use in periodontitis management.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.1
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• pp.81-85
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• 2015

The organic/inorganic hybrid photovoltaic devices have been studied using Poly(3-hexylthiophene-2,5-diyl) (P3HT) : [6, 6]-Phenyl C61 butyric acid methyl ester (PCBM) and GaN. We traced the effect of short circuit current density with different annealing method under the various concentration and ratio of P3HT:PCBM. During the pre-annealing course, the heat treatments were performed each time at low temperature after the organic layer coated and the samples were heated at high temperature through one or two steps under the post-annealing process. It revealed that the samples with post-annealing process had higher values of short circuit current density than the other samples upon pre-annealing. And the interesting high short circuit current density features were observed at 1:1 mixing ratio and 1wt% of P3HT:PCBM.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.458-465
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• 1999

Distribution of the proteolytic activities of crude pretense extracted from the viscera of ten kinds of fish was examined. Their proteolytic activities on proteinous substrates (azocasein, hemoglobin, and casein) from the viscera of anchovy, bastard flatfish, mackerel and red sea bream were higher than those of other fishes, and the crude pretenses were further fractoinated with acetone or ammonium sulfate. Optimum concentrations for pretenses fractionation were $0\~55\%$ for acetone and $30\~70\%$ for ammonium sulfate. The fractionated viscera pretense of mackerel showed the highest proteolytic activity among four kinds of fishes. Activities of cathepsin D- and pepsin-like enzymes at pH 3.0, cathepsin L-, B-, H- and G-like enzyme at pH 6,0, and Hypsin- and chymotrypsin- like enzymes (pH 8.0) were detected in the fractionated viscera pretense, whereas activities of cathepsin L- and chymoeypsin-like enzyme were observed in commercial pretenses. Proteolytic activities of Alcalase, Protamex, and Aroase AP-10 for azocasein were slightly higher than the fractionated viscera pretenses, but their amidolytic activities at pH 6.0 and 8.0 toward synthetic substrates were lower than counterpart. The fractionated pretenses from fish viscera would be utilized as commercial pretenses.