• Food Science and Biotechnology
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• v.17 no.3
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• pp.679-682
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• 2008

A lactic acid bacterium producing an antimicrobial substance against Escherichia coli O157:H7 was isolated from raw milk and identified as Lactobacillus amylovorus ME-1. In addition to E. coli O157 :H7, the antimicrobial substance also inhibited the growth of Bacillus cereus, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyrogenes, and Yersinia enterocolitica. The antimicrobial substance was stable at pH 2-12 and $121^{\circ}C$ for 15 min and insensitive to proteinase K, protease, amylase, and catalase. Purification of the antimicrobial substance was conducted through methanol and acetonitrile/ethylacetate extraction, ultrafiltration with a 500 Da cutoff, thin layer chromatography (TLC) with silicagel 60, and high performance liquid chromatography (HPLC) with a $C_{18}$ reverse phase column. The ${\lambda}_{max}$ of the purified antimicrobial substance was determined as 192 nm by ultra violet (UV) scanning, while the molecular weight was estimated as 453 Da based on the mass spectrum. Accordingly, the current results suggest that the antimicrobial substance from the L. amylovorus ME-1 was not a bacteriocin, but rather a new non-proteinaceous substance distinct from acidophilin, acidolin, diacetyl, and reuterin.

• Journal of Korean Academy of Nursing
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• v.39 no.3
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• pp.446-457
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• 2009

Purpose: The aim of this study was to construct a structural equation model that would further explain the continuously increasing substance use disorder in Korean adolescents. Methods: Survey visits using a structured questionnaire were conducted with 3,885 students in 2 middle schools and 2 high schools in Busan. A total of 13 instruments were used in this model. The analysis of data was done with both SPSS 14.0 for descriptive statistics and AMOS 5.0 for covariance structure analysis. Results: Based on the constructed model, belief on substance use was found to have a significantly direct effect in influencing adolescent substance use. In addition, other factors such as family environment, satisfaction with school life, self-concept, social support, and personality vulnerability indirectly affected substance use. The final modified model yielded Chi-square=2,987(p<.001), df=121, ${\chi}^2$/df=22.1, GFI=.96, AGFI=.93, NFI=.91, PNFI=.72, PGFI=.72, RMSEA=.07 and exhibited fit indices. Conclusion: This study constructed a model that addresses the factors related to adolescent substance use and explains the relationship of these factors in influencing substance use among Korean adolescents. Findings from this study can contribute to designing appropriate prevention strategies to reduce substance related disorders in adolescents.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.4
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• pp.145-152
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• 2004

Red sedimentation substance contains large portion of Fe. The earth retaining structure of a tunnel and ground water containing more portion of Fe than other area are the major factor of this substance In case of white sedimentation substance, the most frequently founded ingredient is CaO, which is occurred in case grouting injection materials for ground reinforcement is transmitted into a tunnel system by ground water. This substance is doesn't affect safety of a tunnel Black sedimentation substance is often found in tunnels near station. This substance is a mixture of either white or red sedimentation substance and detergent material in station transmitted to a tunnel drainage system.

• Korean Journal of Child Studies
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• v.28 no.6
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• pp.85-101
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• 2007

The subjects for this study on delinquent behavior, substance use and risk/protective factors consisted of 301 Korean-American students in grades 6 to 12. Findings were that (1) the delinquent behavior rate of adolescents using alcohol, tobacco or other substances was higher than that of non-using adolescents, increasing the odds of delinquent behavior from 3 to 45 times. (2) The probability of delinquents in the substance users group was higher by 7 to 44 times than in the non-users group. (3) The relationship with delinquent behavior of risk factors and substance use was much stronger than the relationship with delinquent behavior of protective factors and substance use. (4) The strongest predictor of delinquent behavior or substance use was the peer-individual domain.

• The Korean Journal of Food And Nutrition
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• v.11 no.6
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• pp.678-682
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• 1998

A strain of Streptomyces sp. SK-862, isolated from soil in Wonju city, was able to prodce a biologically active substance that has a strong inhibitory activity against proteolsis by trypsin. The inhyibitory substance was extracted by n-butanol, and then purified by the adsorption chromatography followed by the reverse-phase high performacne liquid chromatography. The purified substance was stable over the pH range from 2 to 10, but was unstable when treated at 8$0^{\circ}C$ for 60 min. This substance was soluble in water, methanol, ethanol nd butanol, but insoluble in chlorofrom and ethylacetate. The Rf value of the purified substance on the thin layer chromatography were 0.56 in n-butanol : methanol : water(5 : 3 : 1v/v) solvent system compare dto 0.23 in ethanol : ammonium hydoxide : water(8 : 1 : 1v/v) solvent system. This substance has maximum absorption at 259 nm. The chemical reaction of the substance was negative for sugar but positive for ninhydrine and iodine reaction.

• Journal of Environmental Science International
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• v.11 no.1
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• pp.33-40
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• 2002

An antimicrobial substance-producing microorganism was isolated from soil samples. Based of the taxonomic characteristics of its morphological, cultural, physiological properties and 16s rRNA sequence alignment, this microorganism was identified as Pseudomonas aeruginosa, and we named Pseudomonas aeruginosa EL-KM. The optimal culture condition for production of antimicrobial substance was 1% mannitol, 0.4% yeast extract, 0.5% Nacl, 0.2% $K_2SO_4$, 100$\mu$M $MgSO_4$.$7H_2O$, 10$\mu$M $CaCl_2$.$2H_2O$, 1$\mu$M $FeSO_4$.$7H_2O$, 1$\mu$M $MnSO_4$.$4-5H_2O$, initial pH 7 and 200 rpm at 3$0^{\circ}C$. The purification of the antimicrbial substance was performed by silica gel column chromatographys, and fraction with TLC $R_f$ 0.77 value represented good antimicrobial activity. The crude antimicrbial substance was stable within a pH range of 3-10 and temperature range of 4$^{\circ}C$-121$^{\circ}C$ autoclaving. This crude antibacterial substance acted as bacteriolytic agent against Vibrio cholerae non-Ol ATCC 25872, and also exhibited excellent properties, when the substance was demonstrated against many other gram-positive, gram-negative bacteria, yeast and fungi.

• Journal of Society of Preventive Korean Medicine
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• v.3 no.2
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• pp.91-100
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• 1999

Today, toxicology is used for many purpose, in many fields. Classification of special toxic effect is related next 4 important principles. 1. The chemical substance must move to target organ or tissue that can induce Biological effect. For this movement, we have to understand the physical-chemical characteristic of substance, and the rout of absorption, metabolism, diffusion and excretion of toxic substance. 2. Every biological effect that induced by chemical substance is not harmful. For example, some specific chemical substance is not harmful in liver enzyme system. 3. The strength of biological effect induced by chemical substance is deep related with dose. Nearly all substance is not effective below the specific dose, and it may toxic to death over the specific dose. It is the 'Dose - response relationship' But carcinogen may toxic whether it is law dose or not. 4. The information that was obtained by experimental animal test, could have to adapt in human biology. Because biological effect of chemical substance could be different in every biological species. In past, drugs was obtained by animal or plants. But in the future, it could be obtained by biochemistry, and genome project. Therefore, in Oriental medicine, research and approach is needed at this time, and have to develop new method of experience in toxic method.

• The Korean Journal of Pharmacology
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• v.16 no.1 s.26
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• pp.57-63
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• 1980

The Pharmacologic action of ethanol extracts and essential substance obtained from fruits of Evodia rutaecarpa are studied. 1) Motility of the isolated rabbit-intestine was decreased in proportion to the concentration of essential substance. 2) Intestinal contraction induced by acetylcholine 10? 6g/ml was inhibited by the essential substance $10^{-5}g/ml$. 3) Contractile responses of the isolated rabbit-intestine by serotonin $10^{-5}g/ml$ and histamine $10^{-5}g/ml$ were depressed significantly with the essential substance $10^{-5}g/ml$. 4) Alpha adrenergic receptor blocking effect of dihydroergotamine was interfered significantly with the essential substance. 5) Analgesic effect in mice by acetic acid stimulating method was observed significantly with both of the ethanol extracts and essential substance. 6) Blood pressure and respiration of the rabbits were not significantly influenced with the essential substance.

• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.573-578
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• 2003

The effects of removing the endothelium on the vasodilatory response to substance P, calcitonin gene-related peptide (CGRP), and vasoactive intestinal peptide (VIP) was examined in the isolated rabbit renal artery. The vasodilator response to substance P ($0.1{\mu}M$) was completely absent in vessels in which the endothelium had previously been removed. There was no significant difference in the vasodilatation produced in response to CGRP ($0.1{\mu}M$), or VIP ($0.1{\mu}M$) in the intact and removed-endothelium rabbit renal artery segments. L-NAME ($100{\mu}M$) significantly reduced the vasodilatory response to substance P ($0.1{\mu}M$). This inhibition was significantly attenuated when L-arginine (10 mM) was also present in the organ bath along with L-NAME ($100{\mu}M$). Indomethacin ($1{\mu}M$) did not significantly affect the vasodilatation produced in response to substance P ($0.1{\mu}M$). The inhibitory effect of L-NAME ($100{\mu}M$) and indomethacin ($1{\mu}M$) on the vasodilatory response to substance P ($0.1{\mu}M$) was not significantly different from that produced by L-NAME ($100{\mu}M$) alone. This study indicates that substance P induced vasodilatation via an endothelium-dependent mechanism in the isolated rabbit renal artery. It also established that CGRP and VIP induced vasodilatation by an endothelium-independent mechanism and substance P-induced vasodilatation is at least partially via NO.

• Korean Journal of Pharmacognosy
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• v.8 no.3
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• pp.95-101
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• 1977

Substance A, white prismatic crystal, mp $134{\sim}135,\;C_{29}H_{50}O$, substance B, white needle crystal, mp $131{\sim}132^{\circ},\;C_{17}H_{28}O_4$ and substance C colorless oils, bp $84{\sim}85,\;C_{15}H_{24}O$ were isolated from the underground portion of Valeriana fauriei var. dasycarpa $H_{ARA}$(Valerianaceae) according to Thies method. Substance A was confirmed as known sterol, ${\beta}-sitosterol$ by chemical and spectral discussions. Substance B was estimated as hitherto unknown sesquiterpenoid, 11-acetoxylhydroxyvaleranone by chemical and spectral discussions. Substance C was proposed as hitherto unknown sesquiterpenoid 1, 4-dimethyl-7-isopropenyl 4, 5, 6, 8, 9, 10-hexahydroazulene-1-ol by chemical and spectral discussions, and the general biogenetic considerations.