• 공업화학
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• 제16권1호
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• pp.86-92
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• 2005

아크릴 혼성 폴리우레탄 고분자의 열적-기계적 물성 및 내화학성 향상을 위해 프리폴리머 혼합 공정 및 무유화 중합을 통해 폴리(우레탄-에틸 아크릴레이트) 혼성 에멀젼을 합성하였다. 친수성 그룹의 도입을 위해 디메틸올 프로피온산을 사용하였으며, 폴리우레탄 프리폴리머 제조 후 프리폴리머에 에틸 아크릴레이트 단량체를 투입, 트리에틸 아민으로 증화시킨 후, 물에 분산시켜 안정한 에멀젼 액적을 형성하였다. 이 액적에 사슬 연장제인 에틸렌 디아민을 투입하여 폴리우레탄의 분자량을 증가시킨 후, 산화-환원 개시제인 t-BHP/SBS를 이용하여 $50^{\circ}C$에서 무유화 중합을 통해 폴리(우레탄-에틸 아크릴레이트) 혼성 에멀젼을 얻었다. 폴리(우레탄-에틸 아크릴레이트) 혼성 에멀젼의 물성(인장강도, 100% 모듈러스, 신율 및 내용제성)을 단독 폴리우레탄, 폴리(에틸 아크릴레이트) 및 단순 블렌딩에 의한 샘플과 비교 분석하였다.

• Applied Biological Chemistry
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• 제51권2호
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• pp.93-101
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• 2008

본 연구는 내산성과 담즙산 내성이 뛰어나고 건강증진 효과가 우사한 L. acidophilus를 신생아의 분변에서 분리 및 선발하고 이들에 의한 장내 유해미생물 생육억제, 혈중 cholesterol 저하 및 과산화수소에 대한 저항성과 탈지유 발효를 통한 풍미성분 형성, ACE 저해활성, 철분가용성 증진 등에 관한 기초 지식을 확보하여 다양한 생리활성 기능을 가진 유산균을 개발하고자 실시하였다. 실험 결과 신생아(생후 2주 이내)에서 분리된 5종의 L. acidophilus 중 특히 L. acidophilus SD 105는 Listeria sp.에 대한 항균활성, 복합담증산염 분해활성 및 항산화효과가 다른 시험 균주에 비해 모두 높게 나타나 그 이용성이 매우 다양할 것으로 생각된다. 또한 L. acidophilus SD 102는 ACE활성 억제효과가 18%로 시험균주 중에 가장 높았으며 L. acidophilus SD 103은 유단백질 유래 철분가용화 펩타이트 생성능이 높아 철분흡수율 증가와 연관된 probiotic 유산균으로서의 활용가능성이 있는 것으로 사료된다.

• 한국산학기술학회논문지
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• 제11권6호
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• pp.2093-2098
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• 2010

지방간은 대사증후군의 한 형태로 인슐린저항성이 중요한 역할을 한다. 본 연구는 당뇨 및 대사 인자들과 연관성이 있는 것으로 알려진 말초혈액의 사립체 DNA (mtDNA) copy 수와 지방간 및 인슐린저항성 관련 인자와의 연관성을 알아보고자 하였다. 지방간 진단을 위해 음주력 설문과 복부 초음파 검사를 시행하였으며 실시간 중합효소 연쇄반응을 이용하여 말초혈액의 백혈구에서 mtDNA copy 수를 측정하였다. 총 445 명의 대상자 중 지방간이 있는군(fatty liver group)은 148 명이고 정상군은 297 명이었다. 지방간이 있는 군에서 정상군에 비해 mtDNA copy수가 유의하게 낮았다. 비알콜성 지방간과 알코올성 지방간 모두 지방간이 있는 군에서 말초혈액 mtDNA copy 수가 낮았다. 말초혈액의 mtDNA copy 수는 ALT, AST, $\gamma$-GTP, 체질량지수, 허리둘레, 이완기혈압, 유리지방산 수치와 역의 상관관계를 보였다. 말초혈액에서의 mtDNA copy 수는 지방간 여부 및 인슐린저항성 관련 대사 인자들과 높은 연관성이 있었다.

• 한국응용과학기술학회지
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• 제19권1호
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• pp.25-32
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• 2002

Two PU flame-retardant coatings, 2,3-DBPO/N-l00 (DBPON) and 2,3-DBPO/IL (DBPOI), were prepared by curing 2,3-dibromo modified polyester (2,3-DBPO) with isocyanate curing agent Desmodur N-l00 (or Desmodur IL) at room temperature. The physical properties and flame-retardancy of the two coatings were tested and compared. As a result, the pot-life, yellowness index, lightness index difference, $60^{\circ}$ specular gloss, cross-hatch adhesion, viscosity, and accelerated weathering resistance of DBPON were better than those of DBPOI; the fineness of grind of the two coatings were the same; and the drying time, hardness, and abrasion resistance of DBPOI were better than those of DBPON. The flame retardancy of the flame-retardant coatings increased with the content of the flame retarding component, 2,3-dibromopropanoic acid (2,3-DBP); and the LOI values of the two coatings were in a range of $27{\sim}29%$ when the content of 2,3-DBP was 30wt%.

• 한국수산과학회지
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• 제47권3호
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• pp.220-226
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• 2014

Sixty-seven Vibrio parahaemolyticus isolates from surface seawater from the Wando area, on the southern coast of Korea, were analyzed for their susceptibility to 15 different antimicrobials and the presence of virulence genes. According to the disk diffusion susceptibility test, all of the strains studied were resistant to ampicillin and oxacillin, while decreasing percentages were resistant to vancomycin (64.2%), streptomycin (56.7%), amikacin (31.3%), kanamycin (22.3%), cephalothin (20.9%), erythromycin (10.4%), ciprofloxacin (4.5%), and tetracycline (3.0%). All of the strains were susceptible to five antimicrobials: chloramphenicol, gentamycin, nalidixic acid, sulfamethoxazole/trimethoprim, and trimethoprim. Fifty-nine isolates (88.1%) were resistant to three or more classes of antimicrobial and defined as multidrug resistant, and two strains were resistant to seven antimicrobial agents. The minimum inhibitory concentration (MIC) of the 67 V. parahaemolyticus isolates to ampicillin and oxacillin ranged from 512-2,048 and $64-512{\mu}g/mL$, respectively. All 67 isolates were also examined for the presence of the tdh and trh virulence genes using the polymerase chain reaction (PCR). However, no isolates possessed either tdh or trh. The VPA0477 (${\beta}$-lactamase) gene, present in all of the tested strains, was validated as a new specific marker gene in PCR assays for the accurate detection and identification of V. parahaemolyticus.

• Archives of Pharmacal Research
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• 제28권6호
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• pp.660-666
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• 2005

The intestinal microbiota are important to the host with regard to resistance they impart against bacterial infections and their involvement in mediating metabolic functions. Lactic acid producing bacteria such as Lactobacillus play an important physiological role in these matters. The aim of the present study was to isolate Lactobacillus sp. that inhibits enteric pathogens. Initially, 17 isolates from healthy Koreans were collected on Lactobacillus selective medium. Resistance of the isolates to antibiotics including rifampicin, streptomycin, clindamycin and vancomycin was measured. One of the isolate was identified as Lactobacillus ruminus on the basis of bacterial cell morphology, cultural characteristic and biochemical characteristics, 16S rRNA sequence analysis and PCR-RAPD. Antimicrobial activity of the bacterium against Vancomycin Intermediate Resistant Staphylococcus aureus (VISA) and Vancomycin-Resistant Enterococci (VRE) was measured. About $10^4$ cells of VISA or VRE were mixed with 1, 5, and 9 mL of L. ruminus SPM 0211 and the final volume was adjusted to 10 mL with brain heart infusion (BHI) broth. The cell suspension was incubated for 3, 6, 9, and 24 h, serially diluted and then plated on BHI agar plates. As numbers of L. ruminus SPM 0211 were increased, viable cell count of VISA and VRE decreased. The strongest antimicrobial activity of SPM 0211 was observed after 9 h incubation in any mixture, almost completely inhibiting the growth of these two bacteria. The results suggest that the freshly isolated L. ruminus SPM 0211 may be used as a pro-biotic microbe that prevents the colonization of enteric pathogens and can thereby promote good gastrointestinal health.

• Elastomers and Composites
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• 제34권3호
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• pp.229-238
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• 1999

본 연구에서는 제3의 성분으로 벤젠 술폰산계열 반응성 화합물과 ENB 및 DCPD를 사용하여 비diene계 고분자인 EVA를 특수 화학적 처리에 의하여 EVA의 주쇄에 불포화기 즉, 이중결합을 도입시켰다. 또한 이중결합도입 EVA와 diene계 범용합성고무인 CR, SBR과의 블렌드를 통하여 황가 황체를 제조하여 가황체들의 물리적 특성을 비교 검토하였다. 검토결과 원래의 EVA가 갖고 있는 green strength, 사출 압출 성형성, 접착성, 점착성, 치수안정성, 오존저항성 등의 장점은 그대로 살리면서도 황가황이 가능하여 열가소성의 EVA가 갖는 사용온도의 한계 문제와 기계적 특성 즉, 경도, 인장강도, 인장 응력, 신장율 등온 향상시켰다. 비diene계 고분자와 diene계 고분자의 블렌드에 있어서 개질에 대한 연구가 더 수행되어진다면 합성고무에서 나타나는 부족한 가공성, 내산화 안정성, 접착성 등을 크게 향상시킬 수 있을 것이며 아울러 EVA의 융해유동성을 이용한 고무제품 가공공정의 연속화가 가능하게 될 것이다.

• 멤브레인
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• 제25권4호
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• pp.358-366
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• 2015

강도가 강하고 내약품성, 무독성, 내연소성의 장점을 가지고 있는 PVdF (polyvinylidene fluoride) 나노섬유로 기공이 $0.4{\mu}m$ 평막을 제조한 후, 그 평막으로 부직포를 첨가하여 나권형 모듈을 제작하였다. 카올린과 휴믹산으로 조제한 모사용액과 순수를 대상으로 나권형 모듈의 투과선속과 처리율을 비교하여 pH의 영향을 알아보았고, 여과실험 후 물 역세척을 하여 회복률과 여과저항을 계산하였다. 또한, 나권형 모듈을 통과한 처리수를 입상 활성탄(GAC, granular activated carbon)으로 채워진 컬럼에 통과시킨 후, 탁도와 $UV_{254}$ 흡광도를 측정하여 GAC의 흡착 효과를 고찰하였다.

• 한국식품영양과학회지
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• 제28권5호
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• pp.1034-1043
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• 1999

Rheological properties of dough made from waxy barley(Iri28) flour wheat flour mixtures with additives were investigated for the preparation of waxy barley bread using farinograph, extensograph and amy lograph. The water absorption, development time and dough weakness increased as the waxy barley flour level increased in all blends; however, dough stability decreased. Farinogram properties of 10% waxy barley flour added mixture were similar to those of 100% wheat flour. The addition of A.A(ascorbic acid), gluten, HPMC(hydroxy propyl methyl cellulose) improved rheological properties of dough with 30% waxy barley flour added mixture. In particular, stability and weakness of the dough showed greater dough improving effect by addition of A.A. For the extensograph data, strength, resistance and extensibility of dough decreased with increasing level of waxy barley flour. With the addition of additives, extensogram properties were variable for 30% waxy barley flour mixture. Of these additives, gluten had highest value in strength of dough. Addition of A.A and HPMC to 30% waxy barley flour added mixture resulted in an increase in the resistance and a decrease in the extensibility. Waxy barley flour added mixtures showed little higher gelatinization temperature on amylograph data than control. Maximum viscosity reduced as the waxy barley flour level increased. Also 30% waxy barley flour added mixture containing A.A and HPMC showed a decrease in maximum viscosity. But addition of gluten to 30% waxy barley flour mixture resulted an increase in the maximum viscosity. All of 30% waxy barley flour added mixture with additives had lower gelatinization temperature than those without additives. In the SEM images, starch granules were dispersed in a protein matrix. A non continuous, loose protein starch matrix was observed in all waxy barley flour mixture by SEM. Addition of additives gave the dough a more continuous structure with interactions between the starch granule and protein component.

• Journal of Acupuncture Research
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• 제24권1호
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• pp.165-177
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• 2007

Objectives : This study anus to investigate the effects of Rosa Rugosae Radix (RU) herbal acupuncture on the metabolic syndrome in high-fat diet-fed mice. Methods : The experimental groups were fed with high-fat diet (HFD) for 8 weeks to induce metabolic syndrome. During the induction of metabolic syndrome, RU herbal acupuncture at a dosage of 50 mg/kg was carried out on the point of Sinsu(BL23) every day to measure the body weight, feed efficiency, blood glucose levels, insulin resistance index, lipid levels, blood pressure, and weight of liver and adipose tissues (brown adipose tissue from interscapular fat and white adipose tissue from epididymal fat). And after five weeks' induction of metabolic syndrome, RU herbal acupuncture was also performed for 6 weeks to measure the body weight and blood glucose levels. Results: 1. RU herbal acupuncture inhibited increasing body weight and blood glucose levels, with improved insulin resistance. 2. RU herbal acupuncture inhibited increasing levels of total cholesterol, LDL-cholesterol and free fatty acid, while increased HDL-cholesterol levels. 3. RU herbal acupuncture activated anti-hypertensive action. 4. RU herbal acupuncture inhibited increasing weight of white adipose tissues, but not in brown adipose tissues and liver. 5. RU herbal acupuncture lowered blood glucose levels and inhibited increasing body weight in metabolic syndrome-induced ICR mice. Conclusion : Rosa Rugosae Radix (RU) herbal acupuncture showed effectiveeness in prevention and management of metabolic syndrome in clinical application.