• Nutrition Research and Practice
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• 제6권3호
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• pp.187-194
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• 2012

In this study, the antibacterial effect was evaluated to determine the benefits of high speed drying (HSD) and far-infrared radiation drying (FIR) compared to the freeze drying (FD) method. Citrus press-cakes (CPCs) are released as a by-product in the citrus processing industry. Previous studies have shown that the HSD and FIR drying methods are much more economical for drying time and mass drying than those of FD, even though FD is the most qualified drying method. The disk diffusion assay was conducted, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined with methanol extracts of the dried CPCs against 11 fish and five food-related pathogenic bacteria. The disk diffusion results indicated that the CPCs dried by HSD, FIR, and FD prevented growth of all tested bacteria almost identically. The MIC and MBC results showed a range from 0.5-8.0 mg/mL and 1.0-16.0 mg/mL respectively. Scanning electron microscopy indicated that the extracts changed the morphology of the bacteria cell wall, leading to destruction. These results suggest that CPCs dried by HSD and FIR showed strong antibacterial activity against pathogenic bacteria and are more useful drying methods than that of the classic FD method in CPCs utilization.

• Mycobiology
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• 제35권4호
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• pp.210-214
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• 2007

Antibacterial and antifungal activities of liquid culture filtrate, water and ethanol extract (solid culture) of Stereum ostrea were evaluated against 5 bacteria and 3 plant pathogenic fungi. To determine the minimal inhibitory concentration (MIC), we studied $5{\sim}300\;mg/ml$ concentrations against bacteria and fungi separately. The MIC was 10 mg/ml for Bacillus subtilis and 40 mg/ml for Colletotrichum gloeosporioides and Colletotrichum miyabeanus. Liquid culture filtrate was more effective against Gram positive than Gram negative bacteria, and Staphylococcus aureus was the most inhibited (20.3 mm) bacterium. Water and ethanol extracts were effective against both Gram positive and Gram negative bacteria, and water extract was better than ethanol extract. In water and ethanol extract, inhibition zones were 23.6 and 21.0 mm (S. aureus) and 26.3 and 22.3 mm (Pseudomonas aeruginosa), respectively. For plant pathogenic fungi, the highest and lowest percent inhibition of mycelial growth (PIMG) was found 82.8 and 14.4 against C. miyabeanus and Botrytis cinerea in liquid culture filtrate, respectively. In water extract, the PIMG was found to be the highest 85.2 and lowest 41.7 for C. miyabeanus and C. gloeosporioides, respectively. The inhibitory effect of ethanol extract was better against C. miyabeanus than C. gloeosporioides and B. cinerea. Among 3 samples, water extract was the best against tested pathogenic fungi. This study offers that the extracts isolated from S. ostrea contain potential compounds which inhibit the growth of both bacteria and fungi.

• 미생물학회지
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• 제54권3호
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• pp.244-253
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• 2018

이 연구는 분리된 토양 세균에 의해 생성된 항균물질의 효과를 평가하기 위해 수행되었다. 2000여개의 세균 분리주 중 Paenibacillus elgii DS381이 여러 인간 피부 상재균과 병원성 세균에 대해 높은 항균활성을 나타내었다. DS381 균주는 agar well diffusion test에서 모든 대상 세균과 효모에 대해 15.3~26.0 mm 직경의 저해대를 형성하였다. DS381이 생성한 항균 펩티드는 모든 대상 미생물에 낮은 최소저해농도 (0.039-5.000 mg/ml)를 나타내었다. DS381 균주는 lipopeptide 같은 생물계면활성제 생산을 나타내었는데, 배양 상등액의 표면장력을 60.0에서 40.3 mN/m으로 낮추었다. DS381은 또한 $1.56{\pm}0.13U/ml$의 chitinase 활성도 나타내었다. 이 결과들은 P. elgii DS381이 일부 중요한 인간 피부 상재균과 병원성 세균에 대한 효율적인 생물제어제로 사용될 수 있음을 가리킨다.

• 한국수산과학회지
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• 제55권4호
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• pp.431-436
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• 2022

For the safety assessment of microbiological and chemical hazards in katsuobushi, fifteen samples of katsuobushi were purchased from supermarkets. The contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine pathogenic bacteria [Staphylococcus aureus, Salmonella spp., Listeria monocytogenes, Bacillus cereus, Vibrio parahaemolyticus, Clostridium perfringens, Enterohemorrhagic E. coli (EHEC), Yersinia enterocolitica and Campylobacter jejuni/coli] were quantitatively or qualitatively assessed. Additionally, the heavy metals (total and methyl mercury) content, radioactivity (¹³¹ I, ¹³⁴ Cs⁺ and ¹³⁷ Cs) were quantitatively assessed. Microbial and chemical analyses were performed using standard methods in Korean food code. The contamination level of total viable bacteria was 2.70 (1.18-4.42) log CFU/g. Coliforms, E. coli and S. aureus were not detected in any samples. Other eight pathogenic bacteria were negative in all samples. The contamination levels of total and methyl mercury were 0.366 (0.227-0.481) and 0.120 (0.002-0.241) mg/kg, respectively. In addition, radioactivity was not detected in any samples. The results will be helpful in revitalizing domestic use and boosting exports of katsuobushi because the microbiological and chemical safety of katsuobushi has been assured. Furthermore, the results may be used as a basis for performing chemical and microbial risk assessments of katsuobushi.

• Journal of Oral Medicine and Pain
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• 제38권4호
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• pp.299-312
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• 2013

여러 식물의 추출물에 대한 항균효과와 항균작용은 이미 연구되어 있으나, 구강 내 병원균에 대한 연구는 아직 미미한 편이다. 이에 타액에 수 종의 식물 추출물, myrrh, rhatany, chamomomilla를 첨가하여 치주질환과 구취 발생에 중요한 역할을 하는 원인균들에 대한 억제효과를 파악하고자 하였다. 실험에 사용한 생약 추출물은 Myrrh tincture (100 mg/ml), Ratanhia tincture (100 mg/ml), Chamomile tincture (100mg/ml)를 사용하였으며, 충치원인균인 S. mutans GS5, S. sobrinus 6715와 치주염원인균주인 P. gingivalis 2561 및 P. intermedia ATCC 25611, Candida albicans ATCC 18804, E. feacalis ATCC 4083 균주를 대상으로 항균실험하여 다음과 같은 결과를 얻었다. 본 연구에서 사용한 식물 추출물인 myrrh, rhatany, chamomomilla는 수렴작용과 살균작용, 항염증작용을 가지고 있는 물질로서, P. gingivalis, S. mutans, C. albicans 등의 구강 내 병원균에 대한 항균효과나 항균작용이 구명되었다. 또한 가장강한 항균효과를 보인 rhatany를 처리한 이들 병원균을 투과전자현미경 하에서 관찰하였을 때, 심한 형태적 변형이 관찰되었다. 이는 식물 추출물에 의하여 구강 내 유해균을 억제시킴으로써 치주질환과 충치, 구취 및 구강염의 발생을 예방할 수 있다는 것을 의미하므로, 향후 구강 환경 개선을 위한 임상적 근거가 마련될 수 있을 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제16권5호
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• pp.740-747
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• 2006

Amplification by universal consensus sequences in pathogenic bacterial DNA would allow rapid identification of pathogenic bacteria, and amplification of genus-specific and species-specific sequences of pathogenic bacterial DNA might be used for genotyping at the genus and species levels. For design of probes for molecular diagnostics, several tools are available as stand-alone programs or as Web application. However, since most programs can design only a few probe sets at one time, they are not suitable for large-scale and automatic probes design. Therefore, for high-throughput design of specific probes in diagnostic array development, an automated design tool is necessary. Thus, we developed a Web-based automatic system for design of genus-specific and species-specific probes for pathogen detection. The system is available at http://www.miprobe.com.

• 한국응용곤충학회지
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• 제14권4호
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• pp.209-213
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• 1975

본 실험은 Corynebacterium속 식물병원세균에 관한 연구의 일환으로서 Corynebacterium속 식물병원세균의 종 및 속으로서의 특성을 구명하기 위하여 행하여진 것으로서 균체구성단백의 정량은 Lang의 Messier 변법을 사용하였으며 균채 구성단백의 아미노산정량은 미생물 정량에 의하였다. Corynebacterium 속 식물병원세균은 타속의 병원세균에 비하여 다소 적은양의 균체 구성단백을 가지고 있었으며 균체구성단백의 아미노산; Cystein, Trypthophane, Histidine, Phenylalanine 및 Isoleucin에 있어서도 같은 결과를 나타내었다. 허나 이 현상은 종적 혹은 개체의 균주의 특성으로서 분류에는 관계를 갖지 않고 있음이 밝혀졌다

• 상하수도학회지
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• 제33권5호
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• pp.379-388
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• 2019

Chlorination and UV illumination are being widely applied to inactivate a number of pathogenic microbials in the environment. Here, we evaluated the inactivation efficiency of individual and combined treatments of chlorination and UV under various aqueous conditions. UV dosage was required higher in waste water than in phosphate buffer to achieve the similar disinfecting efficiency. Free chlorine generated by electrolysis of waste water was abundant enough to inactivate microbials. Based on these, hybrid system composed of sequential treatment of electrolysis-mediated chlorination and UV treatment was developed under waste water conditions. Compared to individual treatments, hybrid system inactivated bacteria (i.e., E. coli and S. typhimurium) and viruses (i.e., MS-2 bacteriophage, rotavirus, and norovirus) more efficiently. The hybrid system also mitigated the photo re-pair of UV-driven DNA damages of target bacteria. The combined results suggested the hybrid system would achieve high inactivation efficiency and safety on various pathogenic microbials in wastewater.

• 한국임상수의학회지
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• 제19권1호
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• pp.7-13
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• 2002

This study was examined the microbiological adequacy of fish feed treated with high-dose irradiation (5 kGy). 125 flounder (Paralichthys olivaceus) were grouped into 5 and then the fishes were fed the following feeds for 28 days: (1)standard feed; (2)standard feed, inoculated with Edwardsiella tarda ($1{\times}10^8-1{\times}10^9CFU/g$ of feed); (3)standard feed, inoculated with Vibrio anguilarum ($1{\times}10^8-1{\times}10^9CFIT/g$ of feed); (4)standard feed, inoculated with Streptococcus faecalis ($1{\times}10^8-1{\times}10^9CFU/g$ of feed); (5)standard feed, inoculated with Edwardsiella tarda, Vibrio anguillarum and Streptococcus faecalis, and then irradiated the mixed feed to 5 kGy. The flounders feed the mixed diet with Edwardsiella tarda, Wbrio anguillarum or Streptococcus faecalis inoculated feed were showed severe cumulative mortalities of 60, 48 and 52% respectively. The gross and histological changes were observed on the fishes. However, fishs fed with the feed of bacteria inoculation before irradiation demonstrated excellent protection against the bacteria-related disease. The results from experiments with bacteria inoculated feed indicated that the irradiation methods employed were capable of preventing contamination of the fishs with pathogenic bacteria.

• 한국식품조리과학회지
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• 제16권1호
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• pp.40-46
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• 2000

솔잎과 녹차의 물추출물과 에탄올추출물을 액체배지에 0~2%(w/v)첨가하여 5종류의 식중독세균(Listeria monocytogenes, Staphylococcus aureus 196E, Aeromonas hydrophila, Escherichia coli O157:H7, Salmonella typhimurium)을 $10^{5}$~$10^{6}$ cells/ml 되게 접종하여 35$^{\circ}C$에서 24시간 배양하였다. 솔잎과 녹차의 추출물 종류와 농도에 따른 각 식중독세균에 대한 항균활성은 배양액의 생균수 변화를 측정하였으며 이 결과로부터 각 추출물의 최소저해농도와 최소사멸농도를 구하였다. 아울러 솔잎과 녹차의 추출물과 보존료인 sodium benzoate로서 각 세균에 대한 생육저해환의크기를 비교하였다. 솔잎추출물은 Gram 양성균(L. monocytogenes, S. aureus)과 Gram 음성균중 A. hydrophila에 대하여 0.4~l.6% 범위내에서 증식을 억제시켰으며 E. coli와 S. typhimurium은 솔잎추출물에 대하여 강한 내성을 나타내었다. 솔잎 추출물은 시험한 5균주에 대하여 사멸작용은 전혀 나타내지 않았다. 반면에 녹차추출물은 시험한 5균주 모두에 대하여 0.2~l.0% 범위내에서 증식을 억제시켰으며 L. monocytogenes를 제외한 모든 균주를 0.5~2.0% 범위내에서 사멸시키는 강한 항균활성을 나타내었다. 솔잎과 녹차추출물은 특히 S. aureus와 A. hydrophila에 대하여 보존료(sodium benzoate)보다도 강한 항균활성을 나타내었다. 전체적인 항균력의 크기는 녹차 에탄올추출물 > 녹차 물추출물 > 솔잎 에탄올추출물 > 솔잎 물추출물의 순이었다. 이 결과로 미루어 녹차추출물은 다양한 종류의 세균에 대하여 우수한 항균작용을 나타내는 천연 보존료로서의 활용가치가 있을 것으로 판단된다.다.