• 한국식품저장유통학회지
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• 제4권1호
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• pp.17-25
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• 1997

The effects of microwave treatment on the perservation of foods, such as a seaweed soup and sea stoned radish shreds, were studied. Microwave treatment of microbial cell suspensions revealed that viable cells decreased dramatically when heated to 6$0^{\circ}C$. However, it was unlikely that microwave treatment to 60 is enough to decrease the viable cell counts efficiently in a seaweed soup and radish shreds. It was thought that microwave heating to at least 7$0^{\circ}C$ as a final temperature was an important factor to reduce microbial cell counts in foods. When foods were heated to 7$0^{\circ}C$ with a repetitive 15 sec "on" followed by 30 sec "off", no big differences were observed in viable counts during storage at 2$0^{\circ}C$ for 3 days, as compared to those treated with a full power. The microwave treatment with three stages was designed to solve problems associated with variations depending on food volumes and difficulties of heat diffusion in a solid food to be irradiated with a microwave oven. The three stage method was found to have a similar efficiency in the reduction of viable cell counts in foods to microwave treatment at a full power and to conventional methods, such as water bath heating or boiling for 3 min with a gas range.in with a gas range.

• 한국미생물·생명공학회지
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• 제5권4호
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• pp.171-175
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• 1977

분리된 미생물은 pH 4.5내지 pH 8.0에서 100% 안정성을 나타내며 에너지원이 전혀 공급되지 않은 상태에서도 37$^{\circ}C$의 용액중에서 48시간 이고 경과시도 80% 이상의 높은 생존율을 나타낸다. 생리식염수에서는 4$0^{\circ}C$에서 한 시간 방치하는 경우도 90% 이상의 높은 생존율을 나타낸다는 것을 알수 있었다. 이러한 조건들을 검토해볼 때 생장내 조건에서 상당히 안정하며 경구투여제로 투여하기에 충분히 적당하다고 결론지을 수 있겠다. 특히 포만시에 투여하는 것이 더욱 효과적인 것으로 사료되므로 소화제등과 혼용한 약제로 축발하는 것이 바람직하리라 기대된다.

• The Journal of Advanced Prosthodontics
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• 제12권4호
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• pp.233-238
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• 2020

PURPOSE. This study aims to compare the marginal fitness of two types of implant-supported fixed dental prosthesis, i.e., cementless fixation (CL.F) system and cement-retained type. MATERIALS AND METHODS. In each group, ten specimens were assessed. Each specimen comprised implant lab analog, titanium abutment fabricated with a 2-degree tapered axial wall, and zirconia crown. The crown of the CL.F system was retained by frictional force between abutment and relined composite resin. In the cement-retained type, zinc oxide eugenol cement was used to set crown and abutment. All specimens were sterilized with ethylene oxide, immersed in Prevotella intermedia culture in a 50 mL tube, and incubated with rotation. After 48 h, the specimens were washed thoroughly before separating the crown and abutment. The bacteria that penetrated into the crown-abutment interface were collected by washing with 500 µL of sterile saline. The bacterial cell number was quantified using the agar plate count technique. The BacTiter-Glo Microbial Cell Viability Assay Kit was used to measure bacterial adenosine triphosphate (ATP)-bioluminescence, which reflects the bacterial viability. The t-test was performed, and the significance level was set at 5%. RESULTS. The number of penetrating bacterial cells assessed by colony-forming units was approximately 33% lower in the CL.F system than in the cement-retained type (P<.05). ATP-bioluminescence was approximately 41% lower in the CL.F system than in the cement-retained type (P<.05). CONCLUSION. The CL.F system is more resistant to bacterial penetration into the abutment-crown interface than the cement-retained type, thereby indicating a precise marginal fit.

• KSBB Journal
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• 제21권2호
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• pp.110-117
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• 2006

일반적인 세포주의 동결보존은 혈청이 첨가된 배양배지에 10% DMSO를 첨가하여 실행하게 된다. 그러나 무혈청 환경에서 배양되는 세포주를 이용하여 생물의약품을 생산하는 공정에 사용되는 세포주의 경우는 교차오염 방지를 위해 동결보존 역시 혈청을 제거한 상태에서 실시되어야 한다. 본 실험은 무혈청 동결보존이 CHO 세포에 어떠한 영향을 미치는지 알아보기 위하여 실시되었다. 우선, 무혈청 동결보존에서 세포 생존율을 높이기 위해 투과성 및 비투과성 첨가제를 배지에 첨가하는 방법으로 동결보존 및 해동하여 생존율을 측정하였다. 그 결과, 10% DMSO와 0.03 M raffinose를 동시에 첨가한 경우에 76%의 생존율을 확보할 수 있었지만 기존의 혈청을 이용하는 동결보존에는 미치지 못하였다. 두 번째로 무혈청 배지의 동결보존 능력을 알아보기 위해 시판 중인 무혈청 배지와 무혈청 동결보존제를 사용하여 동결 보존 후의 생존율을 비교한 결과, 무혈청 배지를 이용한 실험에서는 혈청 배지를 이용한 동결보존과 유사한 95% 이상의 생존율을 확인할 수 있었다. 이는 무혈청 동결보존제의 동결보존 능력보다 우수한 결과이다. 마지막으로 무혈청 배지를 이용한 장기간 동결보존에서 CHO 세포의 안정성을 확인하기 위하여 무혈청 배지로 동결보존된 CHO 세포를 3개월 단위로 해동하여 생존율 및 성장 회복율을 측정하고, real-time RT-PCR을 통해 삽입된 CHO DHFR 유전자의 안정성을 평가하였다. 혈청배지와 비교할 때, 생존율과 성장 회복율, 유전자 안정성 측면에서 모두 동일한 결과를 보여, 무혈청 배지를 이용한 18개월 이상의 동결보존이 안정적임을 검증할 수 있었다. 결과적으로 생물의약품 공정에서 무혈청 배지를 이용한 동결보존이 혈청을 이용한 동결보존을 대체할 수 있을 것으로 생각된다.

• Journal of Biosystems Engineering
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• 제42권3호
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• pp.227-233
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• 2017

Purpose: Morphological properties of soybean roots are important indicators of the vigor of the seed, which determines the survival rate of the seedlings grown. The current vigor test for soybean seeds is manual measurement with the human eye. This study describes an application of a machine vision technique for rapid measurement of soybean seed vigor to replace the time-consuming and labor-intensive conventional method. Methods: A CCD camera was used to obtain color images of seeds during germination. Image processing techniques were used to obtain root segmentation. The various morphological parameters, such as primary root length, total root length, total surface area, average diameter, and branching points of roots were calculated from a root skeleton image using a customized pixel-based image processing algorithm. Results: The measurement accuracy of the machine vision system ranged from 92.6% to 98.8%, with accuracies of 96.2% for primary root length and 96.4% for total root length, compared to manual measurement. The correlation coefficient for each measurement was 0.999 with a standard error of prediction of 1.16 mm for primary root length and 0.97 mm for total root length. Conclusions: The developed machine vision system showed good performance for the morphological measurement of soybean roots. This image analysis algorithm, combined with a simple color camera, can be used as an alternative to the conventional seed vigor test method.

• 한국식품과학회지
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• 제46권6호
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• pp.778-781
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• 2014

비가열 살균 기술의 하나인 광펄스 기술을 이용하여 마른 김에 존재하는 미생물에 대한 살균 효과와 품질 변화에 대하여 알아보았다. 마른 김에 1,000 V, 5 pps의 조건하에서 7.9 cm의 거리에서 광펄스 조사를 하였을 때 처리 1분 후에는 0.6 log CFU/g, 처리 10분 후에는 1.6 log CFU/g의 사멸 효과를 보였다. 같은 조건에서 광펄스 조사 후 마른 김의 표면 온도는 약 $1.9^{\circ}C$의 상승을 나타냈으며, 색도에 있어서는 명도가 증가하고, 적색도 및 황색도는 감소하는 경향을 보였으며, 처리 시간이 길어질수록 전체적인 색도의 차이가 크게 나타나는 결과를 보였으나 육안으로는 차이 정도를 확인할 수 없었다. 이러한 결과로 미루어 볼 때 광펄스 살균 기술은 품질 변화없이 마른 김에 존재하는 위해 미생물을 효과적으로 감소시킬 수 있을 것으로 판단된다.

• 치위생과학회지
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• 제20권4호
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• pp.213-220
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• 2020

Background: The leaves of Perilla frutescens, commonly called perilla and used for food in Korea, contain components with a variety of biological effects and potential therapeutic applications. The purpose of this study was to identify the components of 70% ethanol extracted Perilla frutescens (EEPF) and determine its inhibitory effects on oral microbial activity and production of nitric oxide (NO) and prostaglandin E2 (PGE2) in lipopolysaccharides (LPS)-stimulated Raw264.7 macrophages, consequently, to confirm the possibility of using EEPF as a functional component for improving the oral environment and preventing inflammation. Methods: One kg of P. frutescens leaves was extracted with 70% ethanol and dried at -70℃. EEPF was analyzed using high-performance liquid chromatography analysis, and antimicrobial activity against oral microorganisms was revealed using the disk diffusion test. Cell viability was elucidated using a methylthiazolydiphenyl-tetrazolium bromide assay, and the effect of EEPF on LPS-induced morphological variation was confirmed through microscopic observation. The effect of EEPF on LPS-induced production of pro-inflammatory mediators, NO and PGE2 was confirmed by the NO assay and PGE2 enzyme-linked immunosorbent assay. Results: The main component of EEPF was rosemarinic acid, and EEPF showed weak anti-bacterial and anti-fungal effects against microorganisms living in the oral cavity. EEPF did not show toxicity to Raw264.7 macrophages and had inhibitory effects on the morphological variations and production of pro-inflammatory mediators, NO and PGE2 in LPS-stimulated Raw264.7 macrophages. Conclusion: EEPF can be used as a functional material for improving the oral environment through the control of oral microorganisms and for modulating inflammation by inhibiting the production of inflammatory mediators.

• Journal of Microbiology and Biotechnology
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• 제33권4호
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• pp.449-462
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• 2023

Previously, we confirmed that Mychonastes sp. 246 methanolic extract (ME) markedly reduced the viability of BxPC-3 human pancreatic cancer cells. However, the underlying mechanism ME remained unclear. Hence, we attempted to elucidate the anticancer effect of ME on BxPC-3 human pancreatic cancer cells. First, we investigated the components of ME and their cytotoxicity in normal cells. Then, we confirmed the G1 phase arrest mediated growth inhibitory effect of ME using a cell counting assay and cell cycle analysis. Moreover, we found that the migration-inhibitory effect of ME using a Transwell migration assay. Through RNA sequencing, Gene Ontology-based network analysis, and western blotting, we explored the intracellular mechanisms of ME in BxPC-3 cells. ME modulated the intracellular energy metabolism-related pathway by altering the mRNA levels of IGFBP3 and PPARGC1A in BxPC-3 cells and reduced PI3K and mTOR phosphorylation by upregulating IGFBP3 and 4E-BP1 expression. Finally, we verified that ME reduced the growth of three-dimensional (3D) pancreatic cancer spheroids. Our study demonstrates that ME suppresses pancreatic cancer proliferation through the IGFBP3-PI3K-mTOR signaling pathway. This is the first study on the anticancer effect of the ME against pancreatic cancer, suggesting therapeutic possibilities and the underlying mechanism of ME action.

• 융합정보논문지
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• 제10권12호
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• pp.183-190
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• 2020

본 연구에서는 황토노각플러스 추출물의 생리활성 평가를 통해 화장품 원료로서의 가능성을 조사하였다. 황토노각 플러스 추출물에 대한 항산화 효과는 DPPH/ABTS 라디컬 소거능 활성 및 FRAP 분석, 세포 생존율은 MTT assay, 항염증 효과는 nitric oxide(NO) 생성억제 및 iNOS 단백질 발현 수준, 항균 효과는 총 3종 균주 Staphylococcus aureus, Staphylococcus epidermidis 및 Escherichia coli에 대한 한천 확산법을 측정하였다. 메탄올추출물(MN)과 열수추출물(WN)의 총폴리페놀 함량은 각각 2.92±0.01 mgGAE/g, 1.67±0.02 mgGAE/g로 나타났다. MN 추출물의 DPPH, ABTS 및 FRAP 값은 모든 농도에서 WN 추출물보다 높게 나타났다. RAW264.7 세포에 대한 두 추출물의 세포 독성은 관찰되지 않았다. 더욱이 1 mg/mL농도에서 MN과 WN 추출물의 NO 생성량은 11.69 μM과 20.4 μM로 측정되었으며, MN 추출물의 iNOS 단백질 발현 수준은 추출물 농도 의존적으로 억제되었다. 또한 MN 추출물은 S. epidermidis 균주에서만 항균효능을 보였다. 이러한 결과들로 황토노각플러스 추출물은 항산화, 항염, 항균효능을 지닌 천연물질 후보로써 가능성이 높다고 판단된다.

• 한국약용작물학회지
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• 제19권5호
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• pp.388-394
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• 2011

Mume fructus is the roasted fruits of Prunus mume and has been used as traditional chinese medicine. In this study, mume fructus extracts were prepared by three different methods including hot water extract (sample1), fermentation extract using Lactobacillus (Sample2-LP and sample-LA) and ethanol extract (sample3). Total polyphenol and flavonoid contents were improved by fermentation process, compared to water extract. Sample 3 showed the highest activity in DPPH radical scavenging. The cytotoxicity of the sample 2-LP was in the range of 83.3% cell viability at $300{\mu}g/m{\ell}$ concentration. Mume fructus extracts in a concentration-dependent manner inhibited melanogenesis and NO synthesis was inhibited. Specifically, the extracts fermented by L. plantarum (sample2-LP) showed higher anti-oxidant activity, anti-inflammatory and skin whitening activity than other extracts. It suggests that sample 2-LP could be potentially used as a resource of materials for functional cosmetics.