• 한국식품조리과학회지
• /
• 제29권3호
• /
• pp.267-274
• /
• 2013

Demand for a rice cake, a popular traditional food in Korea, is rising, but its industrial-scale production is extremely difficult due to its short shelf-life caused by starch retrogradation and microbial spoilage. By means of the sourdough fermentation technique, we attempt to develop rice cakes with a longer shelf-life. Heterofermentative lactic acid bacteria (Weissella koreensis HO20, Weissella kimchii HO22) isolated from kimchi were used to ferment wet-milled rice flour for their abilities to produce exopolysaccharides and to inhibit the microbial spoilage of rice cakes. After 24 hr of fermentation at $25^{\circ}C$, viable cell counts in rice dough increased from $10^6$ CFU/g to $10^8$ CFU/g and total titratable acidity increased from 0.05% to 0.20%, whereas pH decreased from 6.5 to 5.1. Fermented rice flour showed significantly lower peak, trough, and final viscosities as well as breakdown and setback viscosities measured by rapid viscoanalyzer. Both lactic acid bacteria showed in vitro antifungal activity against Penicillium crustosum isolated from rice cakes. The antifungal activity remained constant after the treatments with heat, proteinase K and trypsin, but fell significantly by increase of pH. Rice cakes made of fermented rice flour were found to retard mycelial growth of P. crustosum. The degree of retrogradation as measured by the hardness of the rice cake was significantly reduced by the use of fermented rice flour. The results suggest that use of fermented rice flour has a beneficial role in retarding starch retrogradation and in preventing fungal growth, hence extending the shelf-life of rice cakes.

• 한국수정란이식학회:학술대회논문집
• /
• 한국수정란이식학회 2002년도 국제심포지엄
• /
• pp.108-108
• /
• 2002

포유동물의 암컷 생식기관에 존재하는 다양한 종류의 matrix metallo-proteinase (MMP)는 난소와 자궁의 구성성분의 주기적인 변화를 조절하며 이중 난소의 MMP는 난포의 성장과 배란 그리고 퇴화 동안 조직재구성에 매우 중요한 역할을 한다고 알려져 있다. 본 실험에서는 근래에 새로 발견된 사람의 난포액에 존재하는 분자량 약 110kDa인 MMP-2 isoform GA110을 동정하고 자 하였다. 난포액으로부터 GA110 단백질을 분리하기 위하여 난포액에 5mM ethylenediaminetetraacetic acid(EDTA)를 처리한 후 DEAE Sepharose Fast Flow를 이용한 chromatography를 시행하였다. 그 결과, 난포액 단백질들은 0.2M NaCl 의 분획에서 GA110 활성을 나타내었고 anti-human MMP-2 antibody에 대한 면역반응도 뚜렷이 나타났다. DEAE Sepharose Fast Flow에서 얻은 분획 중 GA110의 활성과 면역반응을 모두 나타내는 분획만을 모아 Gelatin Sepharose 4B affinity chromatography로 다시 분리하였다 분리한 결과 resin에 흡착된 단백질 (eluate) 분획들에서 매우 뚜렷한 GA110 gelatinase 활성을 나타내었으며 면역반응 또한 관찰되었다. 이 분획들의 단백질을 농축한 후 zymography를 시행하여 나타난 GA110 단백질 band를 잘라 내었으며 이로부터 단백질을 electroelution하여 농축한 후 reducing agent인 2-mercaptoethanol를 처리하였다. 이를 전기영동 후 MMP-2 (propeptide region) antibody를 사용하여 immunoblotting 한 결과 70-72kDa의 단백질만이 면역반응을 나타내었다. 마지막으로 위와 같이 준비된 70-72kDa 단백질의 아미노산 서열을 Edman degradation 방법으로 분석하였다. 그 결과 이 단백질의 N 말단의 10개의 아미노산 배열 순서가 알려진 사람의 proMMP-2의 전체 배열순서 중 propetide domain의 N 말단에서부터 다섯 번째에서 시작하여 10개의 아미노산의 서열과 정확하게 일치하였다. 위 결과들로 미루어 사람의 난포액에 존재하는 MMP-2의 새로운 isoform인 GA110은 70-72kDa의 ProMMP-2가 disulfide bond를 통해 homodimer 구조를 이루고 있는 것으로 여겨진다.

• 동의생리병리학회지
• /
• 제22권3호
• /
• pp.691-698
• /
• 2008

The aims of this study are to search herbal medicines that have anti-aging, anti-wrinkle, anti-oxidant and whitening effects. This is preliminary study as a finding for excellent and specific natural agents which inhibit the skin aging and whitening formation. In this study, the articles and the documents, which have been published in domestically or internationally, have been searched and analyzed. Articles were gathered by taking advantage of Society of Cosmetic Scientists of Korea's documents, Pub med database, Korean Medical Database and Korean Studies Information Service System. Among the many species of herbal medicines, we selected the herbal medicines showing superoxide scavenging activities, and 1.1-diphenyl-2-picrylhydrazyl(DPPH) scavenging effects. The herbal medicines were showed anti-wrinkle effects on Metrixmetallo proteinase (MMP-1) inhibition activity and elastase inhibition activity. Also we found herbal medicines that have highly effect of tyrosinase inhibition, L- DOPA inhibition and melanin synthesis inhibition.

• Current Research on Agriculture and Life Sciences
• /
• 제32권3호
• /
• pp.149-154
• /
• 2014

1. Pepsin과 pancreatin 소화물들을 비교한 결과, 순수한 팥 단백질 중에서 소화효소 저항성을 가지는 단백질이 존재하는 것으로 확인되었다. 2. 팥의 주요 단백질을 제거하고 pepsin과 pancreatin으로 소화시켰을 때 더 많은 분해가 일어나는 것으로 보아 팥의 주요단백질들 중에 소화효소 저항성을 가지는 것이 많을 것이라 추측된다. 3. 팥의 주요 단백질들은 장 점막세포와는 크게 작용하지 않는 것을 확인할 수 있었다. 4. 팥 단백질의 데이터베이스 구축과 팥 단백질이 다른 영양소들과의 상호작용을 하는 지에 대한 연구가 진행되어야 할 것이다.

• Tuberculosis and Respiratory Diseases
• /
• 제40권2호
• /
• pp.98-103
• /
• 1993

연구배경 : Retinoblastoma 유전자(Rb)의 비활성화는 여러 종류의 암에서 관찰되어 왔다. Rb의 이형성의 소실(loss of heterozygosity)은 Rb의 비활성화의 가장 흔한 기전으로 소세포폐암에서는 거의 모든 예에서 관찰되나 비소세포폐암에서는 훨씬 낮은 빈도로 관찰된다고 알려져 있다. 이에 저자들은 개흉수술시 얻은 한국인의 비소세포폐암 및 정상폐조직의 DNA 에서 Rb의 변화를 관찰하였다. 방법: 폐암조직 및 정상폐조직에서 proteinase K에 의한 소화 및 phenol-chloroform 추출 방법으로 genomic DNA를 추출한 후 제한효소인 EcoRI으로 소화시키고 agarose gel 에서 전기영동분리시켰다. Southern blot 방법으로 DNA를 nylon 막에 흡착시킨 후 Rb 1 탐식자로 hybridization 시켜 stringent condition에서 세척하여 X-ray 필름에 적당기간 노출시켜 현상하였다. 결과 : 26예의 편평상피세포암중 16예에서 정상폐 DNA 에서 RFLP에 의한 Rb의 이형성이 관찰되었으며 이중 10예 (62.5%)의 폐암조직 DNA 에서 이형성의 소실이 관찰되었다. 17예의 폐선암중 11예의 정상폐 DNA 에서 RFLP에 의한 Rb의 이형성이 관찰되었으며 이중 5예 (45.4%)의 폐암 DNA 에서 이형성의 소실이 관찰되었다. Rb의 비활성화 유무에 따른 두 군 사이에 연령, 성별, 암의 병기, 암의 분화도 및 흡연력의 차이가 없었다. 결론: 이상의 결과로 Rb의 비활성화는 비소세포폐암의 발생기전에 중요한 역할을 하리라 생각된다.

• Journal of Animal Science and Technology
• /
• 제48권6호
• /
• pp.907-920
• /
• 2006

본 실험은 Lactobacillus spp.와 Bacillus spp. 의 Salmonella typhimurium, E. coli 및 Listeria monocytogenes에 대한 억제활성과 송아지 분변 분리균주의 생장 및 억제활성의 특성을 알아보기 위해 실시되었다.Lactobacillus spp.와 Bacillus spp.의 병원성 세균 Salmonella typhimurium에 대한 억제활성은 Lactobacillus helveticus CU631이 가장 높았고, Bacillus spp.는 활성이 약하였다. 송아지 분변 분리균주를 동정한 결과 Lactobacillus pentosus CU13과 CU05, Pediococcus pentosaceus CUR02, Lactococcus lactis ssp lactis CUM14로 확인되었다. Lactobacillus rhamnosus CU02와 Lactobacillus pentosus CU13의 Listeria monocytogenes에 대한 억제활성에 영향을 미치는 배지성분과 첨가수준은 Tween 80 1.0%, peptone 3.0%, yeast extract 3.0%, glucose 3.0% beef extract 3.0%, NaCl 1.0～3.0%이며, whole cell과 세포벽 물질은 Listeria monocytogenes에 대하여 억제활성을 나타내었다. 억제 성향을 강하게 보인 균체 배양액을 80℃로 열처리한 결과 억제력은 나타나지 않았으나 catalase 및 Proteinase-K 처리는 억제활성에 영향을 미치지 않았다. 이 결과 억제활성 물질은 유기산에 의한 것으로 사료된다. Lactobacillus pentosus CU13과 Lactobacillus rhamnosus CU02의 21균주에 대한 억제 능력을 측정한 결과 병원성균주를 포함한 16균주에서 억제활성을 보였으나 5균주에서는 억제성향을 나타내지 않았다. Escherichia coli O157:H7을 감염시킨 mouse 중 Lactobacillus pentosus CU13을 접종한 경우 다소 체중 회복 현상이 나타났으나, Lactobacillus rhamnosus CU02을 접종한 경우 체중 회복이 빠르게 나타났다.

• 한국축산식품학회지
• /
• 제35권4호
• /
• pp.473-478
• /
• 2015

The aim of this study was to screen and In vitro characterize the properties of bacteriocin produced by lactic acid bacteria isolated from Vietnamese fermented pork (Nem chua). One hundred and fifty LAB were isolated from ten samples of Nem chua and screened for bacteriocin-producing lactic acid bacteria. Antimicrobial activity of bacteriocin was carried out by spot on lawn method against both gram positive and gram negative bacteria. One isolate, assigned as KL-1, produced bacteriocin and showed inhibitory activity against Lactobacillus sakei, Leuconostoc mesenteroides and Enterococcus faecalis. To characterize the bacteriocin-producing strain, optimum temperature, incubation period for maximum bacteriocin production and identification of bacteriocin-producing strain were determined. It was found that the optimum cultivation temperature of the strain to produce the maximum bacteriocin activity (12,800 AU/mL) was obtained at 30℃. Meanwhile, bacteriocin production at 6,400 AU/mL was found when culturing the strain at 37℃ and 42℃. The isolate KL-1 was identified as L. plantarum. Antimicrobial activity of cell-free supernatant was completely inhibited by proteolytic enzyme of trypsin, alpha-chymotrypsin and proteinase K. Bacteriocin activity was stable at high temperature up to 100℃ for 10 min and at 4℃ storage for 2 d. However, the longer heating at 100℃ and 4℃ storage, its activity was reduced.

• 한국식물병리학회:학술대회논문집
• /
• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
• /
• pp.76.1-76
• /
• 2003

The coat protein (CP) of Turnip crinkle virus (TCV) is organized into 3 distinct domains, R domain (RNA-binding) connected by an arm, 5 domain and P domain. We have previously shown that the CP of TCV strongly suppresses RNA silencing, and have mapped N-terminal R domain of which is also the elicitor of resistance response in the Arabidopsis ecotype Di-17 carrying the HRT resistance gene. In order to map the region in the TCV CP that is responsible for silencing suppression, a series of CP mutants were constructed, transformed into Agrobacterium, coinfiltrated either with HC-Pro (the helper component proteinase of tobacco etch potyvirus) known as a suppressor of PTGS or GFP constructs into leaves of Nicotiana benthmiana expressing GFP transgenically. In the presence of HC-Pro, all CP mutants were well protected, accumulating mutant CP mRNAs and their proteins even 5 days post-infiltration (DPI). In the presence of GFP, some mutant constructs which showed the accumulation of CP mutants and GFP mRNAs at early stage but eventually degraded at 5 DPI. Only a mutant which carrying 4 amino acid deletion of R domain was tolerable to maintain suppressing activity, suggesting that the suppressing activity is not directly related with the eliciting activity. A transient assay also revealed that the mutants synthesized their proteins, suggesting that a full length of CP sequences and its intact structure are required to stabilize CP, which suppresses the RNA silencing.

• 한국축산식품학회지
• /
• 제38권5호
• /
• pp.1064-1079
• /
• 2018

In this study, the antimicrobial activity of a bacteriocin produced by Enterococcus faecalis KT11, isolated from traditional Kargı Tulum cheese, was determined, and bacteriocin KT11 was partially characterized. The results showed that bacteriocin KT11 was antagonistically effective against various Gram-positive and Gram-negative test bacteria, including vancomycin- and/or methicillin-resistant bacteria. The activity of bacteriocin KT11 was completely abolished after treatment with proteolytic enzymes (proteinase K, ${\alpha}$-chymotrypsin, protease and trypsin), which demonstrates the proteinaceous nature of this bacteriocin. Additionally, bacteriocin KT11 remained stable at pH values ranging from 2 to 11 and after autoclaving at $121^{\circ}C$ for 30 min. In addition, the activity of bacteriocin KT11 was stable after treatment with several surfactants (EDTA, SDS, Triton X-100, Tween 80 and urea) and organic solvents (chloroform, propanol, methanol, ethyl alcohol, acetone, hexane and ethyl ether). Cell-free supernatant of E. faecalis KT11 was subjected to ammonium sulfate precipitation and then desalted by using a 3.5-kDa cut-off dialysis membrane. The bacteriocin activity was determined to be 711 AU/mL in the dialysate. After tricine-SDS-PAGE analysis, one peptide band, which had a molecular weight of ~3.5 kDa, exhibited antimicrobial activity. Because the bacteriocin KT11, isolated from E. faecalis KT11, exhibits a broad antimicrobial spectrum, heat stability and stability over a wide pH range, this bacteriocin can be used as a potential bio-preservative in foods. Additionally, bacteriocin KT11 alone or in combination with conventional antibiotics may provide a therapeutic option for the treatment of multidrug-resistant clinical pathogens after further in vivo studies.

• BMB Reports
• /
• 제32권1호
• /
• pp.86-91
• /
• 1999

The sprT gene encoding Streptomyces griseus trypsin (SGT) was introduced into Streptomyces lividans TK24 and Streptomyces lividans 1326 to study which strain would be better to overexpress the extracellular proteinase. Various media with different compositions were also used to maximize the productivity of SGT in heterologous hosts. The SGT productivity was best when the transformants of S. lividans TK24 and 1326 were cultivated in R2YE medium, and their relative trypsin activity of the culture broth measured with an artificial chromogenic substrate, N-${\alpha}$-benzoyl-DL-arginine-${\rho}$-nitroanilide, were 382 units/ml and 221 units/ml, respectively. They produced high levels of SGT in GYE medium but relatively lower than those in R2YE medium, and negligible amount of SGT was produced in Ferm, RASF, LIVID, and NDSK media. Considering non-SGT associated activity in Pronase powder, it was estimated that the transformant of S. lividans TK24 can produce SGT in R2YE 3.5 times more than the amount by S. griseus 10137 from which the sprT gene had been originated. The growth of S. lividans reached the maximum level of cell mass at 5 d of culture, but SGT production started in the stationary phase of cell growth and kept increasing until the ninth day of culture in R2YE medium, but in GYE media the productivity reached at the maximum level at 7 d of cultivation.