• Journal of Microbiology and Biotechnology
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• 제27권3호
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• pp.542-551
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• 2017

Small phytochemicals have been successfully adopted as antibacterial chemotherapies and are being increasingly viewed as potential antibiofilm agents. Some of these molecules are known to repress biofilm and toxin production by certain bacterial and yeast pathogens, but information is lacking with regard to the genes allied with biofilm formation. The present study was performed to investigate the inhibitory effect of burdock root extract (BRE) and of chlorogenic acid (CGA; a component of BRE) on clinical isolates of Klebsiella pneumoniae. BRE and CGA exhibited significant antibiofilm activity against K. pneumoniae without inflicting any harm to its planktonic counterparts. In vitro assays supported the ${\beta}$-lactamase inhibitory effect of CGA and BRE while in silico docking showed that CGA bound strongly with the active sites of sulfhydryl-variable-1 ${\beta}$-lactamase. Furthermore, the mRNA transcript levels of two biofilm-associated genes (type 3 fimbriae mrkD and trehalose-6-phosphate hydrolase treC) were significantly downregulated in CGA- and BRE-treated samples. In addition, CGA inhibited biofilm formation by Escherichia coli and Candida albicans without affecting their planktonic cell growth. These findings show that BRE and its component CGA have potential use in antibiofilm strategies against persistent K. pneumoniae infections.

• 한국응용과학기술학회지
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• 제37권2호
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• pp.279-286
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• 2020

치아우식증 치료물질을 개발하기 위하여 한국에서 전통적으로 널리 사용되어왔던 20종류의 약용식물로부터 추출물을 분리하였다. 이를 이용하여 치아우식증 원인균인 Streptococcus sobrinus KCOM 1157에 대한 항균 활성을 나타내는 약용식물들을 조사하였다. 감초, 고삼, 황련, 박하, 송절, 부평초 등의 추출물들이 S. sobrinus KCOM 1157에 대해서 항균 활성을 보여주었다. 이 중 송절, 고삼, 황련 등의 천연물들은 높은 항균 활성을 나타내었다. 이 결과들은 송절, 고삼, 황련의 천연물들이 S. sobrinus 를 포함한 구강질환 세균들에 대한 항우식증 치료제로서의 가능성이 있음을 의미한다.

• Mycobiology
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• 제43권1호
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• pp.9-13
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• 2015

Medicinal fungi, taken whole or as various forms of extracts, have been used to alleviate, cure or prevent human ailments since pre-historic times. In particular, Asian cultures have incorporated a variety of mushrooms into their medical practices. Chemically pure, bioactive metabolites from fungi have been a mainstay of modern pharmacological research and in addition to antibiotics, include anticancer agents, immunosuppressants, enzyme inhibitors, antagonist and agonists of hormones, and a variety of psychotropic substances. However, to date not many studies have focused on the possible health benefits of odorant volatile organic compounds (i.e., gas phase compounds). An analysis of these compounds for their health related effects will expand the range of compounds available for the treatment of chronic and acute diseases. This review highlights phenolic acids and monoterpenes from Asian medicinal mushrooms (AMMs), which not only produce pleasant odors but also have antioxidant and antibacterial effects. Odorant bioactive volatile phase compounds from medicinal mushrooms remain an essentially untapped source for future medicines, and AMMs remain a promising resource for future pharmacological research.

• 대한의생명과학회지
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• 제21권4호
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• pp.233-240
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• 2015

Some virulence proteins of Helicobacter pylori, such as vacuolating cytotoxic protein A (VacA) and cytotoxin-associated gene protein A (CagA) have been reported to be causative agents of various gastric diseases including chronic gastritis, gastric ulcer or gastric adenocarcinoma. The expression level of these virulence proteins can be regulated when H. pylori is exposed to the antibacterial agent, cyanidin 3-O-glucoside (C3G) as previously reported. In this study, we analyzed the quantitative change of various virulence proteins including CagA and VacA by C3G treatment. We used 2-dimensional electrophoresis (2-DE) to analyze the quantitative change of representative ten proteome components of H. pylori 60190 ($VacA^+/CagA^+$; standard strain of Eastern type). After 2-DE analysis, spot intensities were analyzed using ImageMaster$^{TM}$ 2-DE Platinum software then each spot was identified using matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) or peptide sequencing using Finnigan LCQ ion trap mass spectrometer (LC-MS/MS). Next, we selected major virulence proteins of H. pylori among quantitatively meaningful ten spots and confirmed the 2-DE results by Western blot analysis. These results suggest that cyanidin 3-O-glucoside can modulate a variety of H. pylori pathogenic determinants.

• 대한의생명과학회지
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• 제23권3호
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• pp.277-280
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• 2017

Elsholtzia splendens, which grows on moist soil of mountainous regions, is widely distributed at all regions of Korea, especially at Mountain Ji ri. It is categorized as a Labiatae plant which is dried aerial part. It has the following medicinal properties; removal of fever, alleviation of pain, a good antiphlogistic agent as well as antibacterial effects. However, the effects of E. splendens on thrombosis and platelet activation are not precisely understood. We performed this study to develop antithrombotic agents from oriental medicine herb extracts. E. splendens inhibited platelet aggregation induced by arachidonic acid and U46619 in a concentration dependent manner. E. splendens did not show an effect on anticoagulation as determined by prothrombin time (PT) or activated partial thromboplastin time (aPTT). We also tested the effects of E. splendens using a carotid artery thrombosis rat model induced by 35% $FeCl_3$ treatment. E. splendens significantly inhibited thrombus weight compared with the control group. These results show that E. splendens may be developed as a potential antiplatelet activity agent for treatment of cardiocerebrovascular disease and atherosclerosis.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.794-797
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• 1999

Lactobacillus acidophilus is known to have an inhibitory activity on growth of Helicobacter pylori and this activity has been attributed to lactic acid and antibacterial agents produced by Lactobacillus. Since every Lactobacilli produces lactic acid, an another factor must exist for L. acidophilus to inhibit H. pylori growth. In this work, the inhibitory activity of L. acidophilus on H. pylori adherence was studied. An immunoabsorbent assay using TLC plate was developed and used for screening the inhibitory activity of various Lactobacilli on H. pylori adherence. Glycolipid, the attachment site for H. pylori, was isolated from blood type O red blood cells and spotted on a TLC plate. The H. pylori adherence increased linearly with increasing amounts of glycolipid spotted on the TLC plate. Various L. acidophilus strains, but not L. casei, appeared to inhibit H. pylori adherence to glycolipid, and the adherence decreased linearly as the concentration of the Lactobacillus increased. The results show that the inhibitory activity of L. acidophilus on H. pylori adherence is an another factor for L. acidophilus to inhibit H. pylori growth.

• 한국수산과학회지
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• 제52권6호
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• pp.596-604
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• 2019

Vibrio parahaemolyticus causes food poisoning, mainly via marine fisheries products. We investigated the virulence factors and drug resistance of V. parahaemolyticus isolated from fisheries products purchased from the Yeosu Fisheries Market. The isolates were identified using a variety of biochemical tests and the detection of toxR and hns gene. The presence of the virulence factor-encoding genes tdh and trh in the isolates was also investigated by PCR. The resistance of the isolates to 13 antibacterial agents was tested using the disc-diffusion method and carriage of β-lactamase genes and class 1 integrons by ampicillin-resistant isolates was investigated by PCR. Four of seventeen isolates identified as V. parahaemolyticus by biochemical tests produced a species-specific PCR band. Those isolates showed >98% 16S rRNA gene sequence homology with V. parahaemolyticus and only one isolate harbored the tdh gene. All of the V. parahaemolyticus isolates were resistant to ampicillin and amoxicillin; moreover, VPA0477, a class A β-lactamase gene, and class 1 integrons were detected. Therefore, V. parahaemolyticus from fisheries products represents a low risk to human health. Also, V. parahaemolyticus is likely to develop multidrug resistance because it has class 1 integrons.

• Natural Product Sciences
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• 제21권4호
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• pp.278-281
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• 2015

Chemical investigation on a colonial marine tunicate, Didemnum sp. led to the isolation of a series of indole alkaloids including a new (1) and two known metabolites (2-3). Based on the spectroscopic analysis including 1D and 2D NMR along with MS spectra, the structure of 1 (16-epi-18-acetyl herdmanine D) was elucidated as a new amino acid derivative. The absolute configuration of 1 was determined by comparison of specific rotation with the known compound. The structures of compounds 2 and 3 were also identified as bromoindole containing compounds N-(6-bromo-1H-indole-3-carbonyl)-L-arginine and (6-bromo-^1H-indol-3-yl) oxoacetamide, respectively, based on $^1H$ and $^{13}C$ NMR data, MS data and specific rotation value. Their pharmacological potentials as antibacterial agents and FXR antagonists were investigated, but no significant activity was found. However, the structural similarity of compound 1 to compound 4 suggested the anti-inflammatory potential of compound 1.

• Journal of Life Science
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• 제11권2호
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• pp.94-98
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• 2001

Type I signal peptidase cleaves the signal sequence from the amino terminus of membrane and secreted proteins afters these protein insert across the membrane. This enzyme serves as a potential target for the development of novel antibacterial agents due to its unique physiological and biochemical properties. Despite considerable research, the signal peptidase assay still remains improvement to provide further understanding of the mechanism and high-throughput inhibitor screening of this enzyme. In this paper, three known signal peptidase assays are tested with an E. coli D276A mutant signal peptidase to distinguish the sensitivity of each assays. In vitro assay using the procoat synthesized by in vitro transcription translation shows that the D276A signal peptidase I was inactive while in vivo processing of pro-OmpA expressed in the temperature-sensitive E. coli strain IT41 as well as in vitro assay using pro-OmpA nuclease A substrate show that D276A signal peptidase I has activity like wild-type signal peptidase. These results suggest that in vitro assay using the pro-OmpA nuclease A and in vivo pro-OmpA processing assay are more sensitive monitors than in vitro assay using the pro-coat. In conculsion, caution should be used when interpreting the in vitro results using the procoat.

• 한국임상수의학회지
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• 제25권1호
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• pp.40-43
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• 2008

A 5-year-old male Shih-Tzu dog was referred with the primary complaint of scrotal swelling after surgery of urethrotomy 1 week ago. A diagnosis of the patient was made based on history taking, physical examination, laboratory examination, radiography, and ultrasonography. In the blood analysis, increase of leukocyte was seen. And there were enlarged and heterogeneous parenchyma of right testis in ultrasonic evaluation. The case was diagnosed as periorchiepididymitis and followed by treatment with bilateral orchiectomy and postoperative antibacterial agents. And conditions of patient were good.