• Journal of Microbiology and Biotechnology
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• 제5권3호
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• pp.125-131
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• 1995

A 3, 346 bp of the cdd upstream region in Bacillus subtilis was sequenced from the pSO1 (Song BH and J Neuhard. 1989. Mol. Gen. Genet 216: 462-468) and sequence homology was searched to the known genes in Genbank and European Molecular Biology Laboratory databanks. Five complete and one truncated putative coding sequences deduced from the nucleotide sequence were found through the ORF searching by Genetyx and Macvector software, and one of them was identified as the dgk (diacylglycerol kinase) gene and another, a truncated one, as the phoH (phosphate starvation-inducible gene) gene. The B. subtilis dgk gene, having a role for response to several environmental stress signals, revealed an open reading frame of 134 amino acids with 43.1% of sequence identity to the Streptococcus mutans dgk gene. The carboxy terminal 59 residues of the truncated phoH gene showed 52.7% and 34.5% of sequence identity in amino acids with the corresponding genes of Mycobacterium leprae and Escherichia coli. The four remaining coding sequences consisting of 115, 421, 91, and 91 residues were thought to be unknown ORFs because they have no significant similarity to known genes.

• Journal of Microbiology and Biotechnology
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• 제23권7호
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• pp.953-958
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• 2013

Selaginella tamariscina is a traditional herb used in medicine. Phytochemical amentoflavone, a biflavonoid class of flavonoids, was isolated from the plant of Selaginella tamariscina. In this study, the antibacterial effects and combination effects of amentoflavone and conventional antibiotics such as ampicillin, cefotaxime, and chloramphenicol were investigated. These results showed that amentoflavone had a considerable antibacterial effect and synergistic interaction with antibiotics against various bacterial strains (fractional inhibitory concentration index ${\leq}$ 0.5), except for Streptococcus mutans. To study the mechanism(s) involved in the synergistic activities between amentoflavone and antibiotics, we detected hydroxyl radical formation using 3'-(p-hydroxyphenyl) fluorescein and measured the $NAD^+/NADH$ ratio by $NAD^+$ cycling assay. The results indicated that the formation of hydroxyl radical would be a cause of the synergistic effect and that this oxidative stress originated from a transient NADH depletion. This study suggests that amentoflavone synergizes with antibiotics and has potential as a therapeutic agent for antimicrobial chemotherapy.

• 통합자연과학논문집
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• 제7권4호
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• pp.241-252
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• 2014

A series of N-benzoylated ligands incorporating three different benzoyl groups 2,2'-(benzoyliminodiethylene)-4-substituted phenols ($L^{1,4,7}$), 2,2'-(4-nitrobenzoyliminodiethylene)-4-substituted phenols ($L^{2,5,8}$) and 2,2'-(3,5-dinitrobenzoyliminodiethylene)-4-substituted phenols ($L^{3,6,9}$) were synthesized and characterized by IR, $^1H$ NMR, $^{13}C$ NMR and mass spectroscopy. The In vitro antibacterial activity of investigated ligands were tested against human pathogenic bacteria such as four Gram (-) Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, Vibrio cholera, Vibrio harveyi and two Gram (+) Staphylococcus aureus, Streptococcus mutans. Furthermore, docking studies were undertaken to gain insight into the possible binding mode of these compounds with the binding site of the topoisomerase II (PDB: 4FM9) enzyme which is involved in DNA superhelicity and chromosome seggregation. The N-benzoylated derivatives $L^{5,7,8}$ have significant anticancer activity as Topoisomerase inhibitors. The ligands $L^5$ and $L^8$ were tested for their anticancer activity against human liver adenocarcinoma (HepG2) cell line with the MTT assay.

• 대한치과기공학회지
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• 제21권1호
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• pp.139-144
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• 1999

토양시료로부터 치아우식원인균인 S. mutans에 대하여 항균력을 나타내는 방선균주를 순수분리하여 분리균주를 공시균주로 하여 항생물질 생성에 미치는 환경인자를 규명하였다. 본 공시균주의 항생물질 생성 최적배지조성은 Bacto-soytone 1%, glucose 1%, NaCl 0.5%, $CaCO_3$ 0.1% 였으며 배지의 초기 pH는 7.0이었다. 또한 항생물질은 $28^{\circ}C$에서 진탕배양시 생성의 최적조건이었으며 본 공시균주는 24시간 유도기를 거쳐 배양 72시간째 항생물질의 생성과 더불어 균의 최대증식도를 나타내었다.

• 대한간호학회지
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• 제38권6호
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• pp.914-922
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• 2008

Purpose: To examine the effect of tooth-brushing education on the oral health of preschoolers. Methods: A quasi-experimental design with a non-equivalent control group was used. Two kindergartens were selected and 39 preschoolers from one kindergarten were assigned to the experimental group with tooth-brushing education and 39 from the other kindergarten to the control group. The tooth-brushing education program included 1 session on oral health education, individual tooth-brushing instruction for 1 week and supervised tooth-brushing after lunch for 4 weeks. Oral health behavior including use of tooth paste, tooth-brushing time and method of tooth-brushing, plague, streptococcus mutans, lactobacillus and dental caries were measured before and after the education. Fisher's exact test, t-test and paired t-test with the Window SAS 9.1 program were used to analyze the data. Results: A significant increase in the use of tooth paste, tooth-brushing time and the practice of correct tooth-brushing and a decrease in plague and development of dental caries were observed in the experimental group. Conclusion: This tooth-brushing education was partially effective in improving oral health of preschoolers.

• 대한간호학회지
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• 제34권1호
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• pp.132-140
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• 2004

Purpose: This study was performed to investigate the effects of oral health education on kindergarten children. Method: The study was designed as a quasi-experimental, nonequivalent control group pre -post test design. Data was collected from April 1st to November 30th, 2001. The total samples were sixty seven healthy kindergarten children; the experiment group consisted of thirty three and the control group was thirty four children. The experimental group received an oral health education program daily for 20 minutes for four weeks. Result: There was significant improvements on oral health behavior in the experimental group. Streptococcus mutans and lactobacilli of the salivary variables in the experimental group were significantly higher than the control group. The dmft was lower in the experimental group than the control group, but there was no significant difference between the two groups. However it was significantly lower in the experimental group than control group over time. Conclusion: Oral health education for kindergarten children showed an increase in the use of tooth paste and practicing correct tooth brush usage. Also, it decreased the rate of eating cariogenic food and had a positive effect on oral health through suppressing dental cavities.

• Journal of Microbiology and Biotechnology
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• 제12권2호
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• pp.235-241
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• 2002

Sophorolipid, a biosurfactant produced from Candida bombicola ATCC 22214, showed antimicrobial activity against Bacillus subtilis, Staphylococcus xylosus, Streptococcus mutans, and Propionibacterium acne at 4, 1, 1, 0.5 ppm, respectively. Also, 100 ppm of sophorolipid inhibited $50\%$ of cell growth of plant pathogenic fungus, Botrytis cineria. However, sophorolipid showed no effect on Escherichia coli, indicating that its selective antimicrobial activity depended on the cell wall structure. Treatment of B. subtilis with sophorolipid increased leakage of intracellular enzyme, malate dehydrogenase, indicating a possible interaction of sophorolipid with a cellular membrane. Comparing lactone-type and acid-type sophorolipids, the former showed a higher antimicrobial activity. Supplementing other surfactants showed no significant effects on the antimicrobial activity. Animal study showed that 5 g of sophorolipid per kg body weight by oral administration caused no toxicity, and sophorolipid induced no irritation on the skin. These results show potential use of sophorolipid as an active ingredient in healthcare products.

• 한국식품과학회지
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• 제54권4호
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• pp.386-390
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• 2022

This study aimed to investigate the biological and antibacterial activities of phenolics from Sambucus sieboldiana var. pendula leaf extract. The phenolic contents of the S. sieboldiana var. pendula extracted with water and ethanol was 11.60 and 12.39 mg/g, respectively. The inhibitory effects of the water and ethanol extracts on the angiotensin converting enzyme (ACE) were 71.94-92.08 and 48.42-78.33%, respectively, and on xanthine oxidase (XOase) were 42.11-100 and 35.61-100%, respectively, at a phenolic concentration of 50-200 ㎍/mL. All these effects were found to be concentration-dependent. Additionally, the leaf extracts exhibited excellent antibacterial activities against Streptococcus mutans, Staphylococcus aureus, and Propionibacterium acnes. Hence, S. sieboldiana var. pendula was confirmed to have excellent antihypertensive, antigout, and antimicrobial properties.

• 한국약용작물학회지
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• 제11권5호
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• pp.364-370
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• 2003

서양측백나무의 잎으로부터 정유를 steam distillation법으로 추출하고, GC-MS로 정유 조성성분을 분석하였으며, 28종의 미생물종을 대상으로 항균활성을, DPPH법으로 항산화 활성을, 집모기에 대한 살충효과를 검정하였다. 서양측백나무 정유 주성분은 monoterpene류였으며, d-isothujone, l-fenchone, ${\alpha}-thujone$, camphor, terpin-4-ol 순으로 나타났다. 정유의 박테리아에 대한 항균력은 박테리아 중 Streptococcus pyogenes에서, 그리고 효모 및 곰팡이 중 Candida albicans에서 가장 높게 나타났다. 특히 서양측백나무 정유는 그램 양성균의 박테리아에 대해 가장 장한 항균력을 보였다. 정유는 DPPH radical 소거능을 보유하고 있었으며, $EC_{50}$ 값은 $36\;{\mu}{\ell}/m{\ell}$이었다. 집모기에 대한 살충 효과는 분무, 훈증, 자연증발 등 처리방법에 따라 다르게 나타났으며, 그 중 분무처리가 가장 효과적인 것으로 나타났다. 이상의 결과는 환경 친화적인 항균 및 살충소재로 이용될 수 있을 것이다.

• Restorative Dentistry and Endodontics
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• 제30권1호
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• pp.16-21
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• 2005

본 실험에서는 근관 충전 후 Streptococcus mutans를 이용하여 포스트 와동 형성 전후의 근관부미세 누출을 비교하였다. 40개의 발치된 치아를 치근단의 길이가 14 mm가 되도록 치관부를 제거한 뒤, 06 taper $Profile^{(R)}$로 MAF 크기가 $\#40$이 되게 근관 확대를 시행하였다. 근관 확대 후 continuous wave technique으로 근관 충전을 시행하였다. 실험군은 다음과 같다. 1군은 양성 대조군으로 sealer 없이 근관 충전 하였다. 2군은 음성 대조군으로 sticky wax로 치근면을 완전히 막았다. 3군은 근관 충전 후 전체 길이를 14 mm로 유지하였다. 4군은 근관 충전 후 거타퍼치를 5 mm 길이로 남겨두고 포스트 와동을 형성하였다. 치근을 플라스틱 튜브 안에 위치시켜 치근첨은 Andrade's indicator가 첨가되어 있는 BHI 배지에 접촉되도록 하고 상부에서는 bacteria가 유입되도록 하였다. 실험군 3에서의 색변화는 평균 27.2일 만에 일어났으며 포스트 와동 형성한 4군은 평균 15.7일만에 색변화가 일어났으며 3군과 4군 사이에 통계학적으로 유의차를 나타내었다(P = 0.0007).