• Journal of Microbiology and Biotechnology
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• 제16권8호
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• pp.1320-1324
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• 2006

The pancreatic and neutrophil elastases are associated with several illnesses including lung and vascular diseases, various cancers, and pancreatitis. The development of a potent and specific inhibitor to the elastases could lead to new therapies. In this study, an agar diffusion method was modified to include a substrate-dye conjugate (Elastin-Congo red) as a substrate of elastase and an indicator of elastase inhibitory activity. The Elastin-Congo red agar plates consisted of 0.1 % Elastin-Congo red and 2.5% agar. The elastase and elastase inhibitors were simultaneously loaded into wells, ultimately resulting in halo formations in which the halo diameter decreased as the concentration of elastase inhibitor increased. The concentration of elastase inhibitor in the samples, therefore, was inversely proportional to the halo diameters. This simplified method provided an excellent correlation with the standard microplate technique, which uses a chromogenic substrate. The concentration of elastase inhibitor obtained from the culture supernatant of a recombinant elastase inhibitor produced by the yeast Pichia pastoris was easily determined. This study has established a simple modified and inexpensive agar diffusion method that is potentially useful for the identification, quantification, and screening of new elastase inhibitors.

• 한국식품과학회지
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• 제45권3호
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• pp.370-375
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• 2013

구강구취균 4종을 국내산 프로폴리스를 이용하여 프로폴리스의 농도, 열처리, pH의 변화를 통한 항균효과를 조사하였다. P. gingivalis KCTC 5352가 다소 프로폴리스에 저항적인 모습을 보였으나 그 외의 구강구취균에는 강한 항균활성을 나타내었다. 액체배지를 이용하여 프로폴리스의 농도를 조절하여 구강구치균의 민감도를 조사한 결과, 프로폴리스의 농도가 진할 수록 더 빠른 시간에 큰 활성을 보였으며 일반적으로 $0.22mg/{\mu}L$ 농도의 프로폴리스를 첨가하였을 경우 4-6시간 안에 대부분의 균이 사멸하였다. TEM을 통해 프로폴리스가 균의 세포에 어떤 영향을 미치는가 살펴보았으며 프로폴리스를 첨가한 균의 세포막이 얇아지면서 붕괴되고 안의 내부물질이 유출되면서 세포가 분해됨을 확인하였다. $0.56mg/{\mu}L$ 농도의 프로폴리스를 사용하여 열처리 후와 pH 조절 후의 프로폴리스의 항균활성을 시험한 결과 열에 안정하지 않고, pH가 높아질수록 활성이 약해지는 것으로 나타났다.

• 한국식품영양과학회지
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• 제45권7호
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• pp.1026-1034
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• 2016

본 실험은 식용 가능한 약용식물을 대상으로 하여 항균 활성을 검색하였다. 미생물에 대하여 약용 식물을 50 mg/mL, 100 mg/mL, 200 mg/mL의 농도로 하여 paper disc agar diffusion assay로 항균 활성을 검색한 결과 소목 추출물에서 가장 높은 항균 활성을 나타내었다. 이에 따라 소목의 에탄올 추출물과 열수 추출물을 각각 200 mg/mL, 100 mg/mL, 50 mg/mL의 농도로 하여 paper disc agar diffusion assay로 항균 활성을 검색한 결과 소목 추출물은 그람 양성균에서 높은 항균 활성을 나타내었고, 소목의 에탄올 추출물이 소목의 열수 추출물보다 높은 항균 활성을 나타내었다. 소목 에탄올 추출물과 열수 추출물의 각 분획물을 50 mg/mL의 농도로 하여 paper disc agar diffusion assay로 항균 활성을 검색한 결과 그람 양성균은 클로로포름, 에틸아세테이트, 부탄올 층에서 항균 활성을 나타내었고, 그람 음성균은 항균 활성을 나타내지 않았다. 소목의 항균 물질로 추정되는 brazilin은 주로 에틸아세테이트 분획층에 존재하므로 소목 에탄올 추출물에서 클로로포름, 에틸아세테이트, 부탄올의 항균 활성이 유사한 점으로 미루어 brazilin 외에도 다양한 항균 물질이 존재하여 이들이 복합적으로 작용하여 항균 활성을 나타내는 것으로 생각한다. 현재까지 가장 강력한 항생제로 알려진 vancomycin과의 항균 활성을 비교한 결과 50 mg/mL 농도에서 소목 75% 에탄올 추출물의 항균 활성은 vancomycin 2.5 mg/mL를 사용하였을 때와 유사한 항균 활성을 나타내었다. 소목의 추출물을 가지고 미생물에 대한 최소저해농도를 측정한 결과 C. difficile KCTC 5009, L. monocytogens ATCC 19115의 최소저해농도는 0.06 mg/mL였고, S. aureus KCTC 1916에 대한 최소저해농도는 0.03 mg/mL였다. Vancomycin의 유효혈청농도는 0.005~0.04 mg/mL로 견줄만한 항균 활성을 나타내었다. 소목추출물을 가지고 열 및 pH 안정성을 측정한 결과는 항균력은 C. difficile KCTC 5009, L. monocytogens ATCC 19115, S. aureus KCTC 1916에서 모두 대조구와 비슷하게 억제환이 생성되어 소목 추출물의 항균성 물질은 열 및 pH에 대체로 안정한 결과를 보여주었다. 상기 결과들을 종합해 볼 때 소목 에탄올 추출물이 그람 양성균에 대해 항균활성이 뛰어난 것으로 보아 소목을 그람 양성의 병원성 미생물을 억제하기 위한 항균제제 및 기능성 식품의 소재로써 활용할 수 있다고 판단된다.

• Archives of Pharmacal Research
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• 제21권3호
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• pp.278-285
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• 1998

The microdilution assay recommended by NCCLS (National Committee for Clinical Laboratory Standards) is one of the standardized methods of antibiotic susceptibility test. This method has been widely used clinically to obtain MIC values of antibiotics on pathogenic microorganisms. It is more convenient, rapid and simple to test many samples than other test methods such as agar diffusion assay and broth macrodilution assay. The screening of antimicrobial agents from microbial extracts is too laborious in its process. Therefore, a number of screening methods having more simple procedure have been developed. In our laboratory, we applied microdilution assay for screening the antimicrobial agents. This assay showed dose-response results and was more sensitive than disc diffusion assay in our system. We tested 200 samples of microbial extracts originated from 100 microbial strains and selected several samples as potential candidates. In this report, we show that the microdilution assay is more convenient method in screeing of antibiotic susceptibility than those previously reported.

• 한국식품조리과학회지
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• 제26권2호
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• pp.206-213
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• 2010

In this study, the antibacterial activities of essential oil from Zanthoxylum schinifolium against four Gram-positive bacteria and six Gram-negative bacteria were investigated. The antibacterial activity of the oils was determined using the agar-well diffusion assay, MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration). In particular, essential oil from Z. schinifolium showed higher antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria. Essential oil from Z. schinifolium displayed large inhibition zones especially against Bacillus cereus (31 mm). At concentrations between 0 and $20\;{\mu}g/mL$ the oils showed an antibacterial effect against both Gram-negative and Gram-positive bacteria. The minimum inhibitory concentration (MIC) values against nine bacteria ranged from 1.25 to $5\;{\mu}g/mL$. The minimum bactericidal concentration (MBC) values against eight bacterial ranged from 2.5 to $20\;{\mu}g/mL$, except Shigella sonnei. Furthermore, our finding on the antibacterial activities of essential oils from Zanthoxylum schinifolium validated the use of this plant for medical purposes.

• 한국식품영양학회지
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• 제23권2호
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• pp.154-161
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• 2010

국화 정유의 식중독균에 대한 항균력을 검증하기 위해 국화 정유와 그 주성분인 camphor, chrysanthemyl alcohol, $\alpha$-pinene, $\gamma$-terpinene, ${\alpha}+{\beta}$-thujone를 10종 균주에 대하여 agar-well diffusion 분석법으로 생육 여부를 분서하였다. 실험 결과 국화 정유와 그 지표물질은 Gram 양성균과 음성균 모두에 대해서 탁월한 항균 효과가 나타났다. Agar-well diffusion 분석법 결과 국화 정유와 그 지표물질은 Gram 음성균보다 Gram 양성균에 대해서 강력한 활성을 나타내었다. 국화 정유의 minimum inhibitory concentration은 모든 균주에 대하여 5 ${\mu}g/m{\ell}$에서 균의 생장을 저해하는 효과가 나타났고, minimum bacteriocidal concentration은 S. choleraesuis와 L. monocytogenes에 대해서는 시험농도 내에서 사멸효과가 관찰되지 않았으나, 다른 균주에 대해서는 5~20 ${\mu}g/m{\ell}$에서 살균력이 나타났다. 또한 액체 배양중의 항균효과를 조사한 결과, 국화 정유와 그 지표물질은 24시간 동안 꾸준히 항균력이 지속되었다. 따라서 camphor, chrysanthemyl alcohol, $\alpha$-pinene, $\gamma$-terpinene, ${\alpha}+{\beta}$-thujone를 조성분으로 함유한 국화 정유성분은 10종의 식중독균에 대한 항균활성이 입증되어, 천연 항균제재로서 식품보존료로의 이용이 가능하리라 생각된다.

• Food Science and Biotechnology
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• 제15권3호
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• pp.437-440
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• 2006

To explore the possible usefulness of ${\beta}$-glucans as natural antioxidants, the antioxidant profiles of ${\beta}$-glucan, extracted from Saccharomyces cerevisiae KCTC 7911, and water soluble and insoluble mutant ${\beta}$-glucan, isolated from yeast mutant S. cerevisiae IS2, were examined by five different in vitro evaluation methods: lipid peroxidation value (POV), nitric oxide (NO), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, reducing power, and ${\beta}$-carotene diffusion assay. The antioxidant activities of all ${\beta}$-glucans evaluated in POV test were comparable to or better than that of the known antioxidant, vitamin C. Remarkably, the ${\beta}$-glucan and water insoluble mutant ${\beta}$-glucan possessed 2.5-fold more potent activity than vitamin C at a dosage of 2 mg. Although vitamin C showed 100-fold greater activity than all ${\beta}$-glucans in NO and DPPH tests for measuring the radical scavenging capacity, all ${\beta}$-glucans revealed higher radical scavenging activity than the known radical scavenger, N-acetyl-L-cysteine (NAC), in DPPH test. The water insoluble mutant ${\beta}$-glucan had 2.6- and 5-fold greater antioxidative activity than water soluble ${\beta}$-glucan in NO and DPPH tests, respectively, showing that all ${\beta}$-glucans were able to scavenge radicals such as NO or DPPH. While all ${\beta}$-glucans revealed lower antioxidant profiles than vitamin C in both reducing power activity and ${\beta}$-carotene agar diffusion assay, the ${\beta}$-glucan and water insoluble mutant ${\beta}$-glucan did show a marginal reducing power activity as well as a considerable ${\beta}$-carotene agar diffusion activity. These results confirmed the potential usefulness of these ${\beta}$-glucans as natural antioxidants.

• 대한약침학회지
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• 제25권2호
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• pp.114-120
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• 2022

Objectives: Antivenom serums have been used extensively for over a century and are the only effective treatment option for snake bites and other dangerous animal envenomations. In therapeutic serum centers, a wide range of antivenoms is made from animal serum, mainly equine and sheep, that are immunized with single or multiple venoms. This work aimed to use caprylic acid (CA) to purify therapeutic snake antivenom. Methods: Plasma was obtained from equine immunized with a mixture of venoms. Immunized plasma was obtained by precipitation of different concentrations (2-5%) of CA. This methodology was compared to that based on ammonium sulfate (AS) precipitation. Sediment plasma proteins were purified by ion-exchange chromatography. Protein assay, SDSPAGE, and agar gel diffusion were performed. Results: The total protein precipitation with AS was higher than precipitation with CA, but the best results were obtained when CA was added to the plasma until a final CA concentration of 5% was reached. Chromatography and electrophoresis indicated a stronger band for the 5% CA, and the gel diffusion assay showed antigen-antibody interaction in the purified serum. Conclusion: The use of CA compared to the routine method for purifying hyperimmune serums is a practical and cost-effective method for preparing and producing therapeutic serums. It constitutes a potentially valuable technology for alleviating the critical shortage of antivenom in Iran.

• 한국연초학회지
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• 제5권1호
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• pp.43-47
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• 1983

Tobacco mosaic virus (TMV) was detected from Kimchi by biological and serological assay 5. Kimchi samples three month after cooked were collected, and were inoculated on N. tabacum var. Burley 21 and NC 95. Out of 33 samples, 6 showed typical symptoms induced by TMV, local necrotic lesions on Burley 21 and mosaic on NC 95. All saps from tobacco leaves showed the mosaic symptom reacted positively against TMV antiserum by agar gel double diffusion test. Based on the results, the Kimchi is considered as one of the important inoculum sources in Korea.

• 대한한의학방제학회지
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• 제25권4호
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• pp.449-456
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• 2017

Objective : Coptis rhizoma is traditional herb in Korean medicine, and Pelargonium sidoides extract has been used for relief of acute bronchitis in Western medicine. The present study examined the antibacterial effect of fusion formulation of Coptis rhizoma extract and Pelargonium sidoides extract against bronchial diseases bacteria. Methods : Test sample, fusion formulation of Korean and Western medicine, was prepared by mixing Coptis rhizoma extract and Pelargonium sidoides extract at a ratio of 1:2 (w/w). Antimicrobial properties of test sample were determined by agar diffusion assay and minimum inhibitory concentration (MIC) against bronchus diseases bacteria. Results : In agar diffusion assay, the highest amount of test sample (4 mg/disk) exhibited antibacterial activity against all microorganisms tested. Test sample showed the high activity for S. aureus (19.5 mm), C. diptheriae (16.5 mm), A. fumigatus (19.3 mm), F. nucleatum (22.7 mm) and Mycobactrium sp. (17.3 mm), whereas it showed a low activity for K. pneumonia (9.7 mm). The MIC value was determined as $250{\mu}g/m{\ell}$ against C. diptheriae. Test sample showed better growth inhibitory effects against S. aureus and A. fumigatus with the MIC valus of $125{\mu}g/m{\ell}$. Conclusion : These results suggest the possibility of application to chronic respiratory diseases of fusion formulation of Korean and Western medicine, which was prepared with Coptis rhizoma extract and Pelargonium sidoides extract.