• Korean Journal of Food Science and Technology
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• v.54 no.1
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• pp.75-79
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• 2022

Fresh, washed ginseng can be contaminated with microorganism loads as high as 6.5 log CFU/g for total bacteria and 4.3 log CFU/g for mold. The goal of this study was to test eight antibacterial agents on ginseng. Immersing fresh ginseng washed in 1% (w/w) sodium citrate, sodium diacetate, sodium acetate, citric acid, and sodium lactate solution for 1 h resulted in a bactericidal effect of 31.0-97.5% for total bacteria. Among the organic acids, sodium citrate had the best antibacterial effect, with total bacteria reduced from 6.5 log to 4.9 log CFU/g. A 1% (w/w) vitamin B₁ lauryl sulfate solution with surfactant function by hydrophilic and hydrophobic sites can reduce 2.7 log CFU/g (99.8% inactivation) on total bacteria. In the 1% (w/w) calcium oxide solution, total bacteria were reduced by 3 log, showing an excellent inactivation effect of 99.9%. Calcium oxide is a highly useful material for inactivation of microorganisms in fresh ginseng.

• Research in Plant Disease
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• v.30 no.2
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• pp.194-198
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• 2024

Pathogens of fire blight can survive for a long time on pruning tools, etc., and fire blight can be spread through agricultural implements. In particular, in Korea, pruning is frequently performed to remove flowers, immature fruits, and succulent shoots, and this farm work is known to be a major factor of the spread of fire blight. Therefore, in this study, in order to completely sterilize pathogens on pruning shears, we verified the disinfection effect of disinfectants distributed domestically and used them to identify an effective disinfection method. When disinfecting by immersion after inoculating Erwinia amylovora TS3128 on the scissor blade, 70% ethanol and 1% and 0.2% sodium hypochlorite sterilized immediately 10 sec after immersion, while 30% chlorine dioxide showed little disinfection effect. When disinfecting by spraying, 70% ethanol sterilized bacteria 1 sec after spraying, but 1% and 0.2% sodium hypochlorite disinfected bacteria after 10 and 60 sec, respectively. After cutting the naturally disease occurring branches five and 100 times, the bacteria were not hardly sterilized in immersion treatment in 70% ethanol for 30 sec but perfectly disinfected over 60 sec. Considering these results, pruning shears should be disinfected by frequently immersing them in 70% ethanol for at least 60 sec during pruning work in the field.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.334-341
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• 2004

Polysaccharides were prepared from Orostachys japonicus by extration with hot steam water (OJPl). The OIPl fraction was further purified by Sephadex G-50 gel filtration chromatography to produce FI (polysaccharides) and FII (oligosaccharides) fraction. The average molecular masses o fFI and FII fraction were determined to be 3050 kDa and 13 kDa, respectively. The antimicrobial activity of OIPl was tested against 8 strains of bacteria and one strain of yeast by the disc diffusion method, fluorescein diacetate (FDA) method and broth dilution method. The OIPl exhibited a very strong growth inhibition to Candida albicans. The OIPl remarkably sup­pressed the growth of Salmonella typhimurium and Staphylococcus aureus. The OIPl showed higher growth inhibition to Escherichia coli and Pseudomonas aeruginosa than propolis, positive control. When the anticancer activity of the OIPl, FI or FII was examined against human cancer cell lines and the Sarcoma 180 cells, these widely suppressed the proliferation of cell lines in the MTT assay and morphology study. Especially, they remarkably inhibited the growth of A549, HeLa and AGS cells. Also treatment of cancer cells with OJPl, FI or FII induced apoptotic cell death characterized by DNA fragmentation. The OJPl, FI or FII exhibiting various biological activities such as antimicrobial activity and anticancer activity is expected to be developed as new biohealth products.

• KSBB Journal
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• v.17 no.6
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• pp.537-542
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• 2002

To screening of antimicrobial activity, 95% ethanol and hot water extracts of roots, fruits, leaves, radix and stems of 50 species of traditional herbal medicines were examined. For their growth inhibitory effects on two food-born microorganisms, S. aureus and E. coli O157:H7, by the paper disc diffusion method and the minimum inhibitory concentration(MIC) test. Moutan radicis Cortex and Achyranthis Radix showed the highest inhibitory activities on both S. aureus and E. coli O157:H7. The Inhibition zones of Moutan radicis Cortex on S. aureus and E. coii O157:H7 were 22 mm and 24 mm respectively, and the corresponding inhibition zone of Achyranthis Radix were 23 mm and 22 mm. The MIC or Achyranthis Radix on S. aureus was 156.25 $\mu$g/mL, and the MIC or Achyranthis Radix and Moutan radicis Cortexas on E. coli O157:H7 were 625 $\mu$g/mL and 312.5 $\mu$g/mL, respectively. Their antimicrobial activities in ethanolic extracts were significantly higher than in hot water extracts. In the various solvent fractions prepared from ethanol extract, the ethyl acetate fraction of Achyranthis Radix and the CHCl$_3$ fraction of Moutan radicis Cortexas showed strongest activity.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.214-220
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• 2019

Hwangryunhaedok-tang (HT) is prescribed in oriental medicine to treat inflammation-related diseases. This study examined the anti-bacterial effect to select the index components of Traditional Chinese Medicine (TCM) HT. The disc diffusion method and minimum inhibition concentrations (MIC) tests were conducted to measure the antibacterial activity of HT. The strains were Staphylococcus aureus ATCC 25923 and Escherichia coli 23724. Berberine and geniposide were selected as the index components of HT and were analyzed quantitatively by high-performance liquid chromatography (HPLC). As a result, the inhibition ring was formed at $11.7{\pm}1.3mm$ and $8.7{\pm}0.7mm$ at HT 20 mg and 10 mg on S.aureus ATCC 25923, respectively; and $8.0{\pm}0.0mm$ at HT 20 mg on E.coli ATCC 23724. The MIC were 31.25 mg/mL in S.aureus ATCC 25923 and 125.0 mg/mL in E.coli ATCC 23724. In quantitative analysis for standardization, HT contained 16.55 mg/g of berberine and 81.85 mg/g of geniposide. Overall, when antibiotics are developed using natural products, they may reduce the side effects and inhibit resistant bacteria. If research on HT continuously proceeds, positive developments are expected to be made in oriental medicine as well as in various other industries.

• The Journal of the Korea Contents Association
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• v.22 no.3
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• pp.71-80
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• 2022

In the past, fish diseases were bacterial in aqua farms, but in recent years, the frequency of fish diseases has increased as they have become viral and mixed. Viral diseases in an enclosed space called a aqua farm have a high spread rate, so it is very likely to lead to mass death. Fast identification of fish diseases is important to prevent group death. However, diagnosis of fish diseases requires a high level of expertise and it is difficult to visually check the condition of fish every time. In order to prevent the spread of the disease, an automatic identification system of diseases or fish is needed. In this paper, in order to improve the performance of the disease identification system of Paralichthys olivaceus based on deep learning, the existing pre-processing method is compared and tested. Target diseases were selected from three most frequent diseases such as Scutica, Vibrio, and Lymphocystis in Paralichthys olivaceus. The RGB, HLS, HSV, LAB, LUV, XYZ, and YCRCV were used as image pre-processing methods. As a result of the experiment, HLS was able to get the best results than using general RGB. It is expected that the fish disease identification system can be advanced by improving the recognition rate of diseases in a simple way.

• Journal of Oral Medicine and Pain
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• v.21 no.1
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• pp.153-171
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• 1996

저수준레이저를 이용하여 창상이나 병소의 치유과정에 대한 효과를 조사하기 위하여 많은 연구가 시행되었다. 연구에 의하면 갈륨비소 레이저광이 생체자극효과를 가진다고 하며, 저수준레이저를 조사하면 단백질과 핵산 (DNA) 합성을 자극하여 치은섬유아세포의 증식을 촉진한다고 보고하였다. 외상병소나 근육병소의 치료에 사용된 레이저치료법에 관한 관심이 점증함에 따라 저수준레이저요법 (LLLI)의 치유효과를 설명하기 위하여 분자생물학적 수준의 연구를 시행하기에 이르렀다. 보고에 의하면 Mutans Streptococcide 는 LLLI를 사용시 증식이 촉진되며, 다른 세균에서도 유사한 증식효과가 나타날 것이라고 주장하였다. 그러므로 LLLI가 피부감염을 야기하는 가장 흔한 원인인 Staphylococcus aureus 도 마찬가지로 증식이 촉진되는 지를 조사해볼 필요가 있으며, 또한 감염과 같이 특정 병적 상태에서의 저수준레이저광의 효과는 아직까지 명확하게 밝혀져 있지 않았다. 그러므로 본 연구의 목적은 첫째, Staphyloc occus aureus 의 증식에 대한 저수준레이저광의 효과를 조사하는 실험이며, 둘째 Staphylococcus aureus 로 가염된 피부창상에 대한 저수준레이저광의 효과를 판정하는데 있다. 34개의 Staphylococcus aureus 배양표본을 사용하여 48시간의 세포주기동안 조사기간과 조사시간, 그리고 레이저 펄스(laser pulse)형에 따라 3가지 실험을 시행하여 증식에 가장 효과적인 상태와 가장 비효과적인 상태의 갈륨비소 반도체 레이저펄스를 결정하였다. 이후 지름 약 6 mm의 개방창상을 44마리 백서의 양측 대퇴부에 형성하여 모든 창상에 S. aureus를 감염시켰다. 모든 표본은 펄스형과 조사방법 (중앙조사법과 주변조사법)에 따르는 실험을 하기 위하여 4가지로 분류하였다. 각 백서의 양측 창상중 하나는 1,3,5,7일 마다 각 실험의 방법에 따라 레이저를 조사하고 실험동물의 다른 창상은 대조군으로서 사용하였다. 모든 창상의 면적은 실험 1,3,5,7 일째에 일정한 거리에서 사진촬영하여 면적계를 이용, 측정한 후 통계적인 의의를 조사하였다. 본 연구의 결과는 저수준레이저는 특정 조건하에서 S. aureus의 증식을 촉진하였다. 그러나 S. aureus에 감염된 창상을 저수준레이저로 조사시 치유가 촉진되었다. 중앙 조사법고 주변조사법에 의한 창상치유효과는 통계적인 의의가 보이지 않았다. 따라서 결론적으로 S. aureus 에 감염된 창상에 직접 또는 간접적이든 pulse의 종류에 관계없이 조사하는 경우 치유효과가 나타나는 것은 정사주위 조직의 LLLI 자극효과가 염증의 확산을 억제한다고 말할수 있다.

• Microbiology and Biotechnology Letters
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• v.17 no.1
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• pp.74-80
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• 1989

For improvement of photobiological hydrogen production, Rhodopseudomonas El5-1, a photo-synthetic becterium capable of producing n high yield of hydrogen, was immobilized and conditions for hydrogen production by immobilized cells were examined. The optimum concentration for the combined matrix was obtained when sodium alginate was used at final concentration of 4%. The immobilized cells may reduce the inhibitory effects of nitrogen or oxygen. To minimize the diffusion resistance of the nutrients in alginate gel, the bend size less than 2 mm in diameter was desirable. The immobilized cells were also able to utilize n wide range of organic substrates for the production of hydrogen. The hydrogen producing activity of the immobilized cells was maintained for 20 days without loss of activity during semi-continuous operation of the reactor by feeding of new medium periodically and continuous production of hydrogen could be successfully performed for 30 days.

• Research in Plant Disease
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• v.23 no.1
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• pp.35-41
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• 2017

Pseudomonas syringae pv. actinidiae is the causative agent of bacterial canker of kiwifruit. The population of this pathogen is differentiated into three biovars, biovar 1, 2 and 3, according to their molecular characteristics. In this work, we determined biovars of P. syringae pv. actinidiae strains isolated in Korea since 1997 and stored in Department of Biology, Sunchon National University, Suncheon, Korea. The biovars of P. syringae pv. actinidiae strains were determined by PCR using biovar specific primers developed previously. Of 682 strains investigated, 288 strains belonged to biovar 2, while 394 strains were biovar 3. There were no P. syringae pv. actinidiae strains belonging to biovar 1 among the strains isolated in Korea. Sudden outbreak and spreading of bacterial canker caused by biovar 3 strain suggest that this strain has character of rapid transmission.

• Applied Biological Chemistry
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• v.40 no.2
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• pp.167-171
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• 1997

Methanol extracts from 25 seed samples belonging to the family Leguminosae were subjected to an in vitro screening for their growth-promoting and inhibitory activities towards Bifidobacterium adolescentis, B. longum, B. bifidum, and Lactobacillus casei, using spectrophotometric and paper disc agar diffusion methods under $O_2-free$ conditions, respectively. The responses varied with both bacterial strains and plant species. Among seed extracts, extracts from Glycine max (light-green color) and Arachis hypogaea (dark-brown) enhanced the growth of lactic acid bacteria in media with or without carbon sources, suggesting that bifidus factor(s) might be involved in the phenomenon. This growth-promoting effect was most pronounced with L. casei among lactic acid bacteria used. Additionally, all seed extracts did not adversely affect the growth of the lactic acid bacteria tested.