• YAKHAK HOEJI
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• v.42 no.3
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• pp.248-256
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• 1998

We had already reported that we purified N-${\beta}$-alanyl-5-S-glutathionyl-3,4-dihydroxyphenylalanine (5-S-GAD), a novel antibacterial substance from the immunized adult Sarcoph aga peregrina (Flesh fly). We found that the antibacterial activity of synthetic 5-S-GAD is equal to that of authentic 5-S-GAD without a specificity of antibacterial activity against Gram positive and Gram negative. Significant synergism was detected between 5-S-GAD and streptomycin against streptomycin resistant strain E.coli K12 594. It has an antitumor activity against several tumor cell lines at a concentration of $100{\mu}M$. However, no cytotoxic activity against murine macrophage was detected at a concentration of $500{\mu}M$. Furthermore, haemolytic activity against sheep erythrocytes was not detected at the same concentration. We suggest that the S-conjugation of glutathion with dihydroxyphenylalanine might be important to increase antibacterial activity of dihydroxyphenylalanme.

• Journal of Biomedical Engineering Research
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• v.38 no.5
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• pp.242-247
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• 2017

This study presents a bio-chemical energy harvesting system which can generate electric power from bioorganic substance contained in vermicompost. It produced electricity by inoculating microbial fuel cell(MFC) with earthworm-composted food waste. The generated electricity was converted into usable voltage level for mobile electronics through power conditioning circuits. The implemented prototype showed $200{\mu}W$ of maximum output electric power, which successfully supplied a beacon device which continuously transmitted data to nearby smartphone without a battery. The proposed system can help develop portable or bio-mimetic energy supply for sustainable use with further improvement.

• Journal of environmental and Sanitary engineering
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• v.13 no.2
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• pp.40-46
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• 1998

For a biological control on a plant pathogen, Pryicularia Oryzae, and a mosquito, Aedes aegypti, Bacillus thuringiensis strain AF6 which produces parasporal inclusion, delta-endotoxin, was isolated. The B. thuringiensis strain AF6 was produced not only an antifungal substance(AFS) against P. oryzae, but also a mosquitocidal delta-endotoxin. The AFS of the strain AF6 in more stable at pH 4.0 than pH 10.0. At the mode of action, the AFS of the strain AF6 was inhibited hypha growth on potato agar plate(pH 5.0), and degraded cell walls of P. oryzae.

• Journal of Korean Society of Water and Wastewater
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• v.12 no.4
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• pp.59-69
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• 1998

Biological treatment systems generally can be divided into two main classes of a suspended sludge process and attached one like a fluidized bed reactor. These process are considered to bring remarkable change in species composition of microorganisms, due to difference of a state of biofilm, a concentration and diffusion velocity of dissolved oxygen, a concentration and diffusion velocity of substance or poisonous matter. The change of species composition bring different treatment result for influence factors like F/M ratio, DO concentration, pH or poisonous matter. This study is to investigate the reaction characteristics of both microorganisms, namely, a suspended sludge and attached sludge, through the changes of pH, temperature and substance concentration.

• Journal of Korean Society on Water Environment
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• v.21 no.4
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• pp.398-402
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• 2005

The enzyme Xeronine was investigated as a microbial activating substance in biological wastewater treatment processes. Xeronine as bio-stimulant was injected in the anaerobic sludge and the activated sludge treating wastewater in order to examine the effect of hidden benefits. Bio-stimulant did not show significant improvement of anaerobic treatablity. In the aerobic system, higher bio-stimulant dose condition resulted in slightly more removal of nitrogen and phosphorus. Floc aggregation and zone settling velocity as solid-liquid separation factors in activated sludge systems was enhanced by bio-stimulant. Effects of bio-stimulants injection on improvement of water quality and microbial activity did not clear in terms of normal operation conditions.

• Food Science and Industry
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• v.53 no.1
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• pp.43-55
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• 2020

Most reports demonstrated the substrate specificity-based kinetic properties of chitin or chitosan degrading enzymes. However, there is virtually less information on the high quality and quantity production of chitin or chitosan hydrolysates having a larger than (GlcN)₇ from the hydrolysis of high molecular weight chitosan using specific enzymes and their biological activity. Therefore, the production of such molecules and the discovery of such enzyme sources are very important. Fortunately, the author has established a mass production method of chitosan hydrolysates (GlcN)_n, n=2-13 that have been characterized as a potent antioxidant substance, as well as antifungal and antibacterial activities against Penicillium species and highly selective pathogenic bacteria. In addition, preclinical studies using (GlcN)_n, n=5-25 demonstrated that these molecules played a very important role in maintaining biometric balance. Collectively, it is implicated that the application of these mixed substances to foods with significant biological activity is very encouraging.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.1
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• pp.17-21
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• 2022

The present study aimed to determine whether a hemolymph prepared from Antheraea yamamai larvae had the same biological activities using a Bombyx mori hemolymph prior to exposure to lipopolysaccharide (LPS) in order to induce an inflammatory response. The effects of the hemolymph were determined using a reverse transcription-quantitative polymerase chain reaction to assess the expression of pro-inflammatory molecules. The A. yamamai hemolymph exerted anti-inflammatory effects on LPS-activated human monocytic leukemia cells via Toll-like receptor (TLR) 4-mediated suppression, similar to the B. mori hemocyte extract. Treatment with the A. yamamai hemolymph significantly suppressed LPS-induced upregulated inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA expression at all tested concentrations compared with the control, similar to the B. mori immune-challenged hemolymph. Finally, the A. yamamai hemolymph, like the B. mori immune-challenged hemolymph, suppressed all of these concentrations in a dose-independent manner. These results demonstrate that the hemolymph of A. yamamai exhibited important biologically active substances. Further in-depth functional studies are required to fully understand the mechanisms underlying the biological activities of wild-type silkworm hemolymphs.

• Korean Journal of Biological Psychiatry
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• v.19 no.2
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• pp.99-105
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• 2012

Objectives : This study aims to identify temperament and characteristics of cannabis and methamphetamine abusers for elucidating psycho-biological variables related to certain substance abuse. Methods : A total of 320 patients who registered in the 'Hepatitis C cohorts study of intravenous drug users' between March 2006 and March 2010 participated in this study. Data on demographic variables were obtained and the Temperament and Character Inventory (TCI) and measures for nicotine dependence, alcohol dependence, depression and anxiety were assessed. After comparing TCI between cannabis, methamphetamine, and co-abusers, correlations between TCI and other clinical variables were examined. Results : The methamphetamine abuser group showed significantly higher scores in Novelty Seeking (NS2) and Harm Avoidance (HA3) in temperament than the cannabis abuser and co-abuser groups, whereas the cannabis abuser group had higher scores in purposefulness (SD2), congruent second nature (SD5), and self-directedness (SD) in character than the methamphetamine abuser group. In addition, temperaments and characters correlated with various psychiatric symptoms. Conclusions : We found the differences in temperament and characters among cannabis abusers, methamphetamine abusers. These findings might contribute to further understanding of mechanisms of cannabis and methamphetamine abuse.

• Korean Journal of Environmental Agriculture
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• v.16 no.1
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• pp.1-6
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• 1997

This study was carried out to identify the three antifungal substances isolated from the culture medium of Pseudomonas sp. A-183 which is antagonistic against Phytophthora capsici. The substance A and B showed positive reactions at the Molish test and Anthrone test, but negative one at the Fehling test, strongly suggesting that both substance A and B had nonreducing sugar frameworks. The substance C only exhibited the phenomenon of the UV induced fluorescence. From the qualitative analysis with the spectroscopic techniques such as UV, Mass, IR and NMR, the substance A and B were known to be composed to sugar and fatty acid, and showed a base peak of 171(m/e). It was identified that substance A was $(2-O-L-rhamnosyl-{\alpha}-L-rhamnosyl-{\beta}-hydroxydecanoyl-{\beta}-hydroxy$ decanoic acid) and the substance B was $({\alpha}-L-rhamnosyl-{\beta}-hydroxydecanoyl-{\beta}-hydroxy$ decanoic acid). The substance C was identified as a phenazine from the results of qualitative analysis with the spectroscopic techniques such as UV, Mass, IR and NMR.

• Journal of Environmental Science International
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• v.4 no.2
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• pp.201-214
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• 1995

Design approach of upflow Anaerobic Sludge Blanket(UASB) process based on the biological kinetic parameters are known to be very difficult since the characteristics of the granular slut비e depends on the type of wastewater and size distribution of the granular sludge also depends on the upflow velocity in the UASB reactors. Furthermore, industrial wastewater containing toxic substances has been treated by UASB process without the clear knowledge of toxic effects on the granular slut형e. Hence, the present research was aimed on the intensive evaluation of biological kinetic parameters of the granular sludge in UASB reactor with and without toxic substance of 2, 4-dichlorophenol in order to present the basic design measures for UASB process design. The results could be summarized as follows. The biological kinetic parameters(k and Ks) considerably varied with the granular size of the sludge. Generally, 연e k and ks values of the granular sludge increased with the particle size of the granule. The biological kinetic parameters(k and Ks) of the granular sludge obtained from batch test were not applicable to design purpose of UASB process due to substrate diffusional limitation into the granular sludge in the completely mixed UASB reactors. The toxic effects on k and Ks greatly varied with the granular sixte. And as the toxicant concentration increased, the k value decreased while the Ks value increased. Inhibition constant(hi) for k with the toxicant of 2, 4-dichlorophenol varied from 0.5 to 2.3 depending on the granular sizes while the inhibition constant(Ki) for Ks varied from 20.7 to 80.1, showing the mixed inhibition.