• Title/Summary/Keyword: 최소억제

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Antimicrobial Effect of Commercially Available Mouth Rinsing Solutions and Natural Herbal Extracts on Streptococcus mutans (시판되는 구강양치액과 천연한방 추출물의 Streptococcus mutans에 대한 항균효과 비교)

  • Kim, Sung-Im;Jeong, Moon-Jin;Ahn, Yong-Soon;Kim, A-Reum;Kim, Mi-Na;Lim, Do-Seon
    • Journal of dental hygiene science
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    • v.15 no.3
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    • pp.308-317
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    • 2015
  • This study attempted to identify the possibility of natural herbal extracts as an alternative, preventive agent of caries by comparing antimicrobial activities between natural herbal extracts and mouth rinsing solutions against Streptococcus mutans. Natural herbal plants were extracted with distilled water and ethanol, respectively, to measure the minimum growth inhibitory concentration of S. mutans depending on concentration, and among which, solvents showing high antimicrobial activity were selected to compare their antibiotic effects with those of mouth rinsing solutions. Also, to determine the concentration of natural medicinal herbs that can be used safely in the oral cavity, the extracts were treated to the normal gingival fibroblast cells depending on concentration in order to determine its cytotoxicity using MTT. In terms of the minimum growth inhibition concentration, the growth inhibition of S. mutans was more excellent in the ethanol extract than in the distilled water. When the minimum growth inhibition concentration was compared, Psoralea corylifolia of natural herbal ethanol extracts, and Hexamedine (Bukwang Pharm., Korea) of mouth rinsing solutions inhibited growth of S. mutans at the lowest concentration. When the minimum bactericidal concentration was compared, P. corylifolia of natural herbal extracts, and Hexamedine and Garglin (Dong-A Pharm., Korea) of mouth rinsing solutions eliminated S. mutans at a low concentration. The human gingival fibroblast was treated with natural herbal ethanol extracts at the minimum growth inhibition concentration of 10, 39, and $78{\mu}g/ml$. As the result, no cytotoxicity was found. When this was treated at different minimum bactericidal concentrations, natural herbal ethanol extracts showed cytotoxicity except P. corylifolia.

Vibratory Loads Reduction of a Rotor in Slow Descent using Higher Harmonic Control Technology (고조파제어(HHC) 기법을 이용한 저속 하강 비행중인 로터의 진동하중 억제에 관한 연구)

  • You, Younghyun;Jung, Sung Nam
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.6
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    • pp.440-447
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    • 2013
  • In this paper, a higher harmonic control (HHC) methodology is applied to find the optimum input scenario for the vibratory hub loads reduction. A comprehensive aeroelastic analysis code, CAMRAD II, is used to model the HART (Higher-harmonic-control Aeroacoustic Rotor Test) II rotor, and parametric study is conducted for the best HHC inputs leading to a minimum vibration (MV) condition. The resulting outcomes are compared with the earlier HART II test results. It is indicated that the control input adopted in the MV condition showed less satisfactory results. The new MV condition obtained in the present investigation can achieve 45% lower vibration level than the baseline uncontrolled condition. The optimum HHC input results lead to 3/rev harmonic input having $0.8^{\circ}$ amplitude and $350^{\circ}$ phase angle. About 5% reduction in the required power is possible but accompanies with the increase of vibration level.

Aspalatone의 혈소판 응집 억제작용에 관한 연구

  • 한병훈;서대연;양현옥;강영화;김용철
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.236-236
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    • 1994
  • Acetylsalicylic acid (ASA)와 고려홍삼의 항산화 성분인 maltol을 축합하여 신물질 aspalatone을 합성하고, 흰쥐에서의 지혈시간 연장 효과, 항혈소판 응집 억제 (in Vitro, ex ViVO) 효과 및 생쥐의 혈전 모델을 이용한 항혈전 (in vivo) 효과를 연구하였다. SD계 웅성 흰쥐에 15 mg/kg의 낮은 용량으로 경구투여 할 경우, aspalatone과 ASA는 각각 최소한 8일 연속투여후 지혈시간을 유의적으로 연장시켰으며 같은 용량으로 10일 간 경구투여. 하였을 때, aspalatone 투여군은 대조군에 비하여 지혈시간이 57% (p<0.005) 연장된 반면, ASA 투여군은 44% 연장되었다. 반면, aspalatone의 아세칠 기를 갖지 않는 salicylic acid maltnl ester는 같은 용량에서 지혈시간을 유의적으로 연장시키지 않았다. Aspalatone은 in vitro에서 collagen에 의해 유도된 흰쥐 혈소판 응집을 강력하게 억제하였으나 (IS$_{50}$ = 0.18 mM), ASA와 마찬가지로 ADP에 의한 응집은 억제하지 않았다. Aspalatnne과 다른 대조약물들의 ex vivo에서의 혈소판 응집 억제능은 ASA>dipyridamdle(equation omitted)aspalatone>ticlopidine의 순이었다. 1회 경구투여로 aspalatone은 생쥐의 collagen에 의한 혈전에 기인하는 치사율을 억제하였다 (ED$_{50}$ = 32mg/kg). Aspalatone을 10일 간 투여하면 유효용량이 현저히 감소하여 20 mg/kg에서 치사율을 90% (p<0.001) 억제하였으며, 이러한 항혈전 효과는 투여중단 4일 후에도 지속되었다. 또한, 경구투여시 위궤양을 유발하는 ASA (ulcer index : 29 mm 200 mg/kg p.o.)와는 다르게 aspalatone은 위궤양을 유발하지 않는다는 장점을 갖는다 (0.71 mm, 800 mg/kg p.o.). In vitro에서 malondialdehyde 생성 억제를 지표로 한 aspalatone의 항산화 활성 ($IC_{50}$/ = 0.11 mM)은 maltol ($IC_{50}$/ = 0.084 mM)과 유산하다. 이러한 실험결과를 토대로 하여 aspalatone을 위궤양을 유발하지 않는 항혈전 신약으로 개발하기 위한 연구가 진행 중이다.

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Screening of Antibrowning Agents for Minimally Processed Vegetables (최소가공채소류에 적합한 갈변방지제의 선발)

  • Park, Woo-Po;Cho, Sung-Hwan;Lee, Dong-Sun
    • Korean Journal of Food Science and Technology
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    • v.30 no.2
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    • pp.278-282
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    • 1998
  • Peeled garlic, soybean sprouts, cut onion and cut green pepper were treated by dipping in solutions of different antibrowning agents, and then stored at $10^{\circ}C$. Surface color and polyphenol oxidase activity of produce were measured through the storage. Tested antibrowning agents include ascorbic acid, citric acid and allyl isothiocyanate. The commodities showed different responses to the antibrowning agent solutions; 1% citric acid for peeled garlic, 1% ascorbic acid for soybean sprouts, 2% citric acid for cut onion, and 1% ascorbic acid for cut green pepper showed better retardation in browning than the other treatments for respective product. For peeled garlic, surface browning was concomitant with increase in polyphenol oxidase activity during storage. On the other hand, there was no positive correlation between surface browning and polyphenol oxidase activity for the other stored products.

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Antibacterial Properties Associated with Microorganisms Isolated from Arctic Lichens (북극 지의류 유래 미생물의 항균성)

  • Kim, Mi-Kyeong;Park, Hyun;Oh, Tae-Jin
    • Microbiology and Biotechnology Letters
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    • v.40 no.4
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    • pp.380-388
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    • 2012
  • A total of 5 different polar microorganisms were isolated from Arctic lichens and their bioactive compounds were extracted from cell culture using different solvents including acetone, water, chloroform, diethylether, ethanol, ethyl acetate, methanol, and petroleum ether. The antibacterial properties of the extracts were evaluated by disk diffusion tests and minimal inhibitory concentration tests against 6 bacterial pathogens; Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus, Enterobacter cloacae, Pseudomonas aeruginosa and Escherichia coli. Among the extraction samples, ethyl acetate extracts of Burkholderia sordidicola S5-$B^T$ (KOPRI 26644) showed the highest activity (inhibition zone, 7-10 mm; MIC value, 57.5-1000 ug/ml) against targeted bacteria. Among the various solvents used for extraction, chloroform extract exhibited the weakest, but still obvious, activity.

A study on Antibacterial Activity of Samsinhwan Ethanol Extract against MRSA (삼신환(三神丸) 에탄올 추출물(SSH)의 MRSA에 대한 항균활성 연구)

  • Woo, Haksik;Lee, Yeoung Ju
    • Journal of Digital Convergence
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    • v.17 no.8
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    • pp.271-282
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    • 2019
  • The purpose of this study is to identify the antimicrobial effects of SSH(三神丸) and synerggy effects of the existing antibiotics Oxacillin and Ciprofloxacin on MRSA and to identify the mechanisms. In this case, the procedure and method for verifying anti-bacterial activity and active concentration of MARA by measuring the minimum inhibitory concentration (MIC) of the trichin is used to verify the potency and active concentration of MARA, to confirm the potency of the disease by treating antibiotics and trichine ethanol extract in parallel, and to confirm the anti-bacterial effect over time, when the trichine is activated as an anti-bacterial activity to MARA, and a compound. In addition, we hope that this research will not only serve as meaningful data for the development of new drugs to control MARA immunity, but also serve as an opportunity to further accelerate the research and development of antibiotics to overcome resistant strains.

Natural antibrowning treatments on fresh-cut apple slices (천연 갈변방지제를 이용한 최소가공 사과 절편 개발)

  • Son, Seok-Min
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.1
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    • pp.151-155
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    • 2007
  • A comprehensive study to evaluate the relative antibrowning activity of 5 known natural juices was conducted. Among the juices tested, rhubarb juice showed the highest inhibitory activity on apple browning (${\Delta}L=0.47$ & ${\Delta}E=1.8$ after 6 storage days at $4^{\circ}C$). Even 50% diluted rhubarb juice was very effective in controlling apple discoloration, showing very limited change in Hunter's L and E values. No significant difference in apple slices browning was observed with respect to the packaging material (LDPE or nylon/PE). However, gas composition inside package was closely related to apple browning.

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ANTIMICROBIAL EFFECT OF ESSENTIAL OILS ON ORAL BACTERIA (구강 내 세균에 대한 Essential oil의 항균효과에 관한 연구)

  • Lee, Sun-Young;Kim, Jae-Gon;Baik, Byeong-Ju;Yang, Yeon-Mi;Lee, Kyung-Yeol;Lee, Yong-Hoon;Kim, Mi-A
    • Journal of the korean academy of Pediatric Dentistry
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    • v.36 no.1
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    • pp.1-11
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    • 2009
  • Essential oils are mixture of volatile, lipophilic compounds originating from plants. Essential oils have potential biological effects, i.e., antibacterial, antifungal, spasmolytic and antiplasmodial activities and insect-repellent property. In this study, five essential oils, namely R, LG, FR, O, and NM, extracted from various aromatic plants were used to test their antimicrobial activity against the oral microorganisms. The effects of essential oils were investigated against eight important bacteria, Streptococcus mutans (S. mutans), Staphylococcus aureus (S. aureus), Streptococcus sanguis (S. sanguis), Streptococcus anginosus (S. anginosus), Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), Streptococcus sobrinus (S. sobrinus), Staphylococcus epidermidis (S. epidermidis), and Escherichia coli (E. coli). Essential oils, except NM, effectively inhibited the growth of tested oral pathogenic microorganisms dose-dependently. However, the essential oils didn't show a significant inhibitory effect against E. coli and S. epidermidis. Consequently, these results represented that essential oil-mediated anti-microbial activity was prominent against the oral pathogenic bacteria. For example, minimum bactericidal concentration(MBC) of R, LG, FR oil against A. actinomycetemcomitans was very low as 0.078 mg/mL. In addition, minimum inhibitory concentration (MIC) of R, LG, FR, O oil against S. mutans was low as 0.156 mg/mL in vitro.

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Antimicrobial Activity of Lysimachia clethroides Duby Extracts on Food-borne Microorganisms (식중독 미생물에 대한 큰까치수영(Lysimachia clethroides Duby)의 항균활성)

  • Han, Ji-Sook;Shin, Dong-Hwa
    • Korean Journal of Food Science and Technology
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    • v.33 no.6
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    • pp.774-783
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    • 2001
  • The ethanol extract of 77 species of edible and medicinal plants were examined antimicrobial activity against 5 strains of Listeria monocytogenes ATCC 19111, ATCC 19112, ATCC 19113, ATCC 19114 and ATCC 15313 by optical density using Bioscreen C. The ethanol extract of Siegesbeckia glabrescens Makino, Jeffersonia dubia Benth, Aquilaria agallocha Roxburgh, Lysimachia clethroides Duby and Nardostachys chinensis Batal. exhibited comparatively strong growth inhibition effect on 5 strains of L. monocytogenes at 1000 ppm level in broth. The minimum inhibitory concentration (MIC) of ethanol extract of Lysimachia clethroides Duby was $100{\sim}500\;ppm$ on 5 strains of L. monocytogenes. The MIC of the n-hexane and chloroform fraction of the extract were same concentration as $50{\sim}100\;ppm$. The n-hexane fraction of Lysimachia clethroides Duby showed strong growth inhibition at 25 ppm on Vibrio parahaemolyticus for 72 hr at $30^{\circ}C$ and at 50 ppm on Bacillus cereus and at 500 ppm on Staphylococcus aureus and Escherichia coli.

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Antioxidant, Antimicrobial and Anti-inflammatory Activities of Essential Oil from Erigeron annuus L. Flower (개망초꽃 에센셜 오일의 항산화, 항균 및 항염 활성)

  • Yi, Mi-Ran;Jeon, Ah-Lim;Kang, Chang-Hee;Bu, Hee-Jung
    • Journal of the Korean Applied Science and Technology
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    • v.33 no.4
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    • pp.717-725
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    • 2016
  • This study was designed to examine the in vitro antioxidant, antimicrobial and anti-inflammation effects of essential oils of Erigeron annuus L. Flower. Erigeron annuus L. essential oils were obtained by solvent extraction. Antioxidative ability was evaluated by bioassays using ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) radical scavenging effect and 2, 2-diphenyl-1-1-picrydrazyl (DPPH) free radical scavenging activity. Erigeron annuus L. essential oil exhibited free radical scavenging activity on ABTS and DPPH 98.6%, 48.3% respectively, at a concentration of $500{\mu}g/ml$. Antimicrobial activity of essential oils of Erigeron annuus L. were tested against Staphylococcus aureus (S. aureus), Propionibacterium acnes (P. acne) and Escherichia coli (E. coli) by paper disc method, MIC and MBC. Erigeron annuus L. essential oil showed excellent antibacterial activities against S. aureus with MIC and MBC values of 0.31 mg/mL. The clear zone, indicating antimicrobial activity against P. acnes, was 14 mm, MIC and MBC values 0.31 mg/mL, 0.63 mg/mL, respectively. For the anti-inflammatory activity in RAW 264.7 cell, the Erigeron annuus L. essential oils inhibited not only NO production but also the expression of pro-inflammatory cytokines such as, TNF-${\alpha}$, IL-6 in a dose-dependent manner. These results suggested that Erigeron annuus L. essential oils has considerable potential as a cosmetic ingredient with antioxidative, antimicrobial and anti-inflammation effects.