• 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.

• Korean Journal of Plant Resources
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• v.24 no.1
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• pp.10-16
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• 2011

We investigated the antimicrobial activity of ether and ethylacetate fractions from Artemisia capillaris and Artemisia iwayomogi used as Injin. The antimicrobial activity of the ethylacetate fractions from Artemisia capillaris and Artemisia iwayomogi for tested microbes were stronger than those of ether fractions of the two Artemisia plants. The antimicrobial activity of fractions of Artemisia iwayomogi was higher than that of fractions of Artemisia capillaris for the tested microbes. The extracts of young shoots and leaves showed stronger antimicrobial activity than those of young leaves. The range of minimum inhibitory concentrations(MICs) of ethylacetate fractions from the part of Artemisia capillaris and Artemisia iwayomogi were 0.25~2.0 mg/ml. The MICs of ether fractions were showed higher concentration than those of ethylacetate fractions. The fractions of Artemisia iwayomogi showed lower MICs than fractions of Artemisia capillaris. The highest total polyphenol content was found in young shoots and leaves of A. capillaris. The young shoots and leaves of the two kinds of Artemisia plants showed higher content of total polyphenol.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.539-547
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• 2002

본 연구는 풋콩 탈협기 개발을 위한 기초연구로서 풋콩 탈협기의 급치를 교환할 수 있고, 급동의 주속도와 송풍팬의 회전속도 및 공기 흡입구의 개구면적을 조절할 수 있는 실험장치를 제작하고, 급치의 종류가 풋콩의 탈협 및 손상에 미치는 영향을 분석하였다. 또한 송풍팬의 회전속도와 흡입 공기구의 개구비 변화 따른 선별 성능을 분석하였다. 그 결과를 요약하면 다음과 같다. 1 급치의 종류에 따른 풋콩의 미 탈협율은 철선 급치가 최대 1.6%, 최소 0.0%,평균 0.7%로서 가장 낮게 나타났고, 그 다음이 경도 60의 고무제 급치로서 최대 2.0%, 최소 0.0% 평균 1.1%, 경도 80의 고무제 급치는 최대 2.5%, 최소 0.0% 평균 1.7% 순으로 높아졌다. 또한 풋콩의 미탈협율은 급동 원주속도가 18m/s에서 55m/s로 증가할수록 감소하였다. 이는 급동의 원주 속도가 증가함에 따라 급치의 선단이 풋콩 꼬투리에 가하는 타격력이 증가하기 때문인 것으로 생각된다. 2. 급치의 종류에 따른 풋콩의 손상율은 경도 80의 고무제 급치는 최대 5.2%, 최소 1.3%, 평균 2.8%로서 가장 낮게 나타났고, 그 다음이 경도 60의 고무제 급치로서 최대 5.7%, 최소 2.4% 평균 3.8%, 철선 급치는 최대 6.3%, 최소 2.6% 평균 4.2% 순으로 높아졌다. 또한 풋콩의 손상율은 급동 원주속도가 증가할수록 풋콩 꼬투리의 손상율은 증가하였다. 이 또한 급등의 원주 속도가 증가함에 따라 급치의 선단이 풋콩 꼬투리에 가하는 타격력이 증가하기 때문인 것으로 생각된다. 3. 공기흡입구의 개구면적을 증가시킬수록 선별율은 높게 나타났으나 개구비가 60%이상에서는 선별율이 크게 차이가 나지 않았으며, 송풍팬의 원주속도를 높일수록 선별율은 높게 나타났다.도 콤바인이 직선구간 및 선회구간을 주행하며 수확작업이 가능함을 알 수 있었다. 그러나 곡선구간에서는 최대오차가 65.5 cm로 매우 크게 나타나, 콤바인을 무인 자율주행으로 수확하기에는 어려움이 있는 것으로 나타났다. 실제 포장은 이론적인 완전한 직선보다는 작은 굴곡이 있는 곡선의 형태가 이루어져 있으므로 주행 오차를 감소하기 위해서는 기계시각을 이용하면 보다 정밀한 조향을 이룰 수 있을 것으로 예상된다. 포장에서 DGPS 신호, 자이로 센서 등을 이용한 콤바인의 무인주행 장치는 무인 수확작업을 위한 가능성을 보여주었고, 일부의 센서의 기능을 개선하면 만족한 성능을 나타낼 수 있을 것으로 판단된다.dislocations form local defect arrangements at the grooves permitting the substantial reduction in defect density over the remainder of the interfacial area.한 최대의 감자 재배지역을 형성하였다. 제주도는 산지지형과 따뜻한 기온으로 2기작이 가능하고, 감자가공 공장설립과 교통발달에 따른 육지 시장과의 접근이 용이해졌기 때문에 남한에서 2번째로 큰 감자재배지역이 되었다.(요약 및 결론에서 발췌)그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.서 뚜렷한 증식억제효과를 나타내었다.min/+}$계 수컷 이형접합체 형질전환 마우스에 AIN-76A 정제사료만을 투여한 대조군은 1.40$\pm$

• Clean Technology
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• v.29 no.2
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• pp.135-144
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• 2023

Pseudomonas aeruginosa and Staphylococcus aureus are the two most frequently encountered pathogens responsible for chronic wound infections, often coexisting in such cases. These infections exhibit heightened virulence compared to single infections, leading to unfavorable patient outcomes. The interaction among microorganisms within polymicrobial infections has been shown to exacerbate disease progression. Polymicrobial infections, prevalent in various contexts such as the respiratory tract, wounds, and diabetic foot, typically involve diverse microorganisms, with Pseudomonas aeruginosa and Staphylococcus aureus being the most commonly identified pathogens. This study aimed to compare the growth patterns of bacteria under a concentration gradient of toxic chemicals, focusing on a Gram-negative strain of Pseudomonas aeruginosa and a Gram-positive strain of Staphylococcus aureus. The minimum inhibitory concentration (MIC), which signifies the concentration at which bacterial growth is inhibited, was determined by performing broth microdilution and assessing the bacteria's growth curves. The growth curves of both Pseudomonas aeruginosa and Staphylococcus aureus were confirmed, and the exponential growth phases were applied to calculate the doubling times of bacteria. The MIC value for each toxic chemical was determined through broth microdilution. These results allowed for the identification of disparities in growth rates between Gram-positive and Gram-negative bacteria, as well as differences in resistance to individual toxic substances. We expect that this approach has a strong potential for further development towards the innovative treatment of bacteria-associated infections.

• Korean Journal of Food Science and Technology
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• v.22 no.6
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• pp.716-719
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• 1990

The essential oils were isolated by steam distillation from 13 spices used for curry. Antimicrobial activity of essential oils for two strains of Gram(+) bacteria, Gram(-) bacteria, lactic acid bacteria, yeast and mold were investigated by agar diffusion method. 5 spice essential oils(clove, cumin, nutmeg, oregano, rosemary) having high antimicrobial activity were selected and their minimal inhibitory concentration(MIC) were measured. Very low concentration ($0.2{\sim}9\;mg/ml$) of 5 spice essential oils were sufficient to prevent microbial growth. The data show that Gram(+) bacteria were more sensitive to the antimicrobial compounds in spices than Gram(-). But though Gram(+) bacteria, lactic acid bacteria were less sensitive to the compounds than Gram(-).

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.185.1-185
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• 2003

최근 세계적으로 편의식품의 소비가 증가하면서 과채류의 신선도를 유지시킴과 동시에 편리하게 조리에 이용할 수 있는 최소가공식품(minimally processed foods)의 시장이 확대되고 있다. 그러나, 기개발된 최소가공 과채류는 미생물학적 안전성 및 색 변화 등의 문제점을 수반하여 이 부분을 보완할 수 있는 기술개발이 시급한 실정이다. 따라서 본 연구는 감마선을 이용하여 미생물학적 안전성 및 저장성을 향상시킨 최소가공식품 개발의 일환으로, 김치를 모델식품으로 원료배추의 최소가공식품을 개발하기 위해 미생물학적, 이화학적 품질특성을 조사하였다. 절단한 배추의 염농도가 3%가 되도록 절임 및 함기포장 하고, 0~2 kGy의 선량으로 감마선 조사한 후 4$^{\circ}C$에서 3주 동안 저장, 분석하였다. 비조사구의 경우 총균수, coliform Salmonella spp., lactic acid bacteria 등이 모두 7 log cycle 수준을 보였으며, 감마선 조사시 2-5 log cycle 이상 감소하는 것으로 나타났다. 또한 색도, 물성 등은 감마선 조사에 의해 비조사구와의 유의적인 차이를 보이지 않았으며, 감마선 조사시 절임배추의 발효현상에 의해 나타나는 pH 저하를 억제할 수 있어 저장성을 향상시킬 수 있는 것으로 나타났다. 결론적으로 감마선 조사를 이용한 최소가공 절임배추의 개발시 미생물학적 안전성을 보장하면서, 이화학적 특성이 저하되지 않고 저장성을 향상시킨 최소가공식품을 개발할 수 있었다.

• Journal of the korean academy of Pediatric Dentistry
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• v.36 no.2
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• pp.217-226
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• 2009

Allyl isothiocyanate (AIT), the principle ingredient of antimicrobial ingredients from horseradish root, can be prepared from extracts of horseradish root or synthetic method. It is reported that the horseradish root extract has the antimicrobial effect against various oral microorganisms, while there is no further study about the antimicrobial effect against the oral microorganisms of synthetic AIT derived from synthetic method. The aim of the study is to compare the difference of the antimicrobial effect between horseradish root extracts and synthetic AIT. To evaluate the antimicrobial effect, we measured the minimum inhibitory concentration(MIC) and minimum bactericidal concentration (MBC), and the results are like following. 1. The MIC of horseradish root extract against 7 kinds of oral pathogenic microorganisms is about 117$\sim$1,750 ppm(0.0117$\sim$0.175%), and the MIC of the synthetic AIT is about 344$\sim$3,000 ppm(0.0344$\sim$0.3%), which have the antimicrobial effects against all kinds of microorganisms. 2. The MBC of the horseradish root extracts against the 7 kinds of oral microorganisms is about 625.2$\sim$6,000 ppm(0.06252$\sim$0.6%), and the MBC of the synthetic AIT is about 1,750$\sim$7,000 ppm(0.175$\sim$0.7%), which have the antimicrobial effects against all kinds of microorganisms.

• 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.

• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1396-1402
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• 2000

The effects of Coptis chinensis Franch(CCF) extract on the growth, acid production, cell adherence and glucosyltransferase(GTase) activity of Streptococcus mutans JC-2 were investigated. Methanol extract from CCF showed a strong inhibitory effect on the growth of S. mutans. The minimal inhibition concentration(MIC) of the methanol extract was determined as $130\;{\mu}g/mL$, whereas MIC of water extract was $200\;{\mu}g/mL$. MICs of berberine and palmatine were $50\;{\mu}g/mL$ and $110\;{\mu}g/mL$, respectively, showing stronger antimicrobial activities than the extracts of CCF. Antimicrobial activities of methanol extract, berberine and palmatine were not decreased by heating at $121^{\circ}C$ for 15 min, suggesting that the antimicrobial components including berberine and palmatine are heat-stable. Acid production of S. mutans was decreased by methanol and water extracts, berberine and palmatine. The activity of GTase was inhibited by methanol extract, berberine and palmatine at $300\;{\mu}g/mL$ with 23.2%, 46.1% and 17.1%, respectively, but was not inhibited by water extract. The water extract and palmatine at sub-MICs inhibited the adherence of S. mutans to glass surface by 59.2% and 41.7%, respectively. These results suggest that CCF extracts have anticariogenic effects and could be used as an anticariogenic food additive.

• Journal of Applied Biological Chemistry
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• v.64 no.1
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• pp.83-87
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• 2021

Antimicrobial activity of an aqueous extract from Caesalpinia sappan L. was investigated against skin flora such as Escherichia coli, Staphylococcus aureus, Cutibacterium acnes, and Malassezia furfur. The yield and polyphenol content of the aqueous extract were 14.01±0.81% and 487.5±19.69 ㎍/mg-extract, respectively. The minimum inhibitory concentration of the aqueous extract against E. coli, S. aureus, C. acnes, and M. furfur was 0.875, 1.750, 1.750, and 1.750 mg/mL, respectively. In disc diffusion test, the aqueous extract of C. sappan L. increased the clear zone in a dose-dependent manner. The aqueous extract inhibited the microbial growth in a concentration-dependent manner.