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        검색결과 187

        162.
        2013.03 KCI 등재 서비스 종료(열람 제한)
        유사 올리빈 구조를 가지는 탄소코팅 합성 Li+Fe2+(PO4)3- 분말시료에 대한 상온-고압실험을 대칭 다이아몬드 앤빌기기를 이용하여 35.0 GPa까지 시행하였다. LiFePO4의 압축 데이터를 이용하여 계산된 체적탄성률은 130.1±10.3 GPa이다. 18 GPa 이상의 압력에서 d = 3.386 a 위치에 새로운 피크가 관찰되고 35 GPa에서는 d = 2.854 a에 또 다른 피크가 관찰되고 있으나 주 결정구조는 사방정계인 것으로 판단된다. 압력에 대한 단위 포 부피의 압축은 M1(Li+O6)의 수축이 두드러지고 M2(Fe2+O6)와 사면체(PO4)의 수축은 상대적으로 작은 것으로 나타났다.
        163.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        Water temperature in the eastern part of the Yellow Sea (EYS) during winter (JFM) and summer (JJA) from 1964 to 2009 and Siberian High Pressure Index (SHI) and Arctic Oscillation index (AOI) during winter (JFM) from 1950 to 2011 were used to analyze long-term variation in oceanic and atmospheric conditions and relationship between winter and summer bottom water temperature. Winter water temperature at 0, 30 and 50 m had fluctuated highly till the late of 1980s, but after this it was relatively stable. The long-term trends in winter water temperature at both depths were separated with cold regime and warm regime on the basis of the late 1980s. Winter water temperature at 0m and 50m during warm regime increased about 0.9°C and 1.1°C respectively compared to that during cold regime. Fluctuation pattern in winter water temperature matched well with SHI and AOI The SHI had negative correlation with water temperature at 0 m (r=-0.51) and 50 m (r=-0.58). On the other hand, the AO had positive correlation with Winter water temperature at 0 m (r=0.34) and 50 m (r=0.45). Cyclic fluctuation pattern of winter water temperature had a relation with SHI and AO, in particular two to six-year periodicity were dominant from the early of the 1970s to the early of the 1980s. Before the late of 1980s, change pattern in winter water temperature at 0 and 50 m was similar with that in the bottom water temperature during summer, but after this, relationship between two variables was low.
        164.
        2012.08 KCI 등재 서비스 종료(열람 제한)
        This study was performed to enhance contents of low molecular weight ginsenoside Rh2 and Rg3 using an ultra high pressure and steaming process in wild cultured-Root in wild ginseng. For selective increase in contents of Rg3 and Rh2 in cultured wild ginseng roots, an ultra high extraction was applied at 500MPa for 20 min which was followed by steaming process at 90℃ for 12 hr. It was revealed that contents of ginsenosides, Rb1, Rb2, Rc and Rd, were decreased with the complex process described above, whereas contents of ginsenoside Rh2 and Rg3 were increased up to 4.918 mg/g and 6.115 mg/g, respectively. In addition, concentration of benzo[α]pyrene in extracts of the cultured wild ginseng roots treated by the complex process was 0.64 ppm but it was 0.78 ppm when it was treated with the steaming process. From the results, it was strongly suggested that low molecular weight ginsenosides, Rh2 and Rg3, are converted from Rb1, Rb2, Rc, and Rd which are easily broken down by an ultra high pressure and steaming process. This results indicate that an ultra high pressure and steaming process can selectively increase in contents of Rg3 and Rh2 in cultured wild ginseng roots and this process might enhance the utilization and values of cultured wild ginseng roots.
        165.
        2012.06 KCI 등재 서비스 종료(열람 제한)
        TiO2의 동질이상체 중 하나인 아나타제는 고압 하에서 결정의 크기와 모양에 따라 다른 상변이 경로를 보이는 것으로 알려져 있다. 본 실험에 이용된 아나타제 분말시료는 15~25 nm 정도 크기의 입자로 구성되어 있으며, 고압라만분광분석 결과와 고압 X-선회절실험결과 분석을 종합하면 20 GPa 이상의 압력에서 비정질로 상변이하는 것으로 관찰되었다. 상온에서 압력의 영향으로 상변이한 비정질 구조는 압력을 제거하여도 출발 결정구조로 회귀하지 않는 것으로 밝혀졌다. 이 결과는 베델레이트로 상변이하는 이전의 결과와 상치되며, 출발시료 구성입자의 분급상태가 입자의 불안정성에 영향을 끼쳐 최종적으로 비정질화에 기여한 것으로 판단된다.
        166.
        2011.04 KCI 등재 서비스 종료(열람 제한)
        This study was performed to enhance anticancer activities of Lithospermum erythrorhizon by eluting high amount of shikonin through ultra high pressure process. Extraction yield was increased up to 5~10% by ultra high pressure process, compare to the normal extraction processes such as water solvent extraction, 70% ethyl alcohol solvent extraction. The cytotoxicity of the extracts (1.0μg/ml) from ultra high pressure process was showed the lowest cytotoxicity 13.4% for human lung cell (HEL299). The anticancer activities showed 80~85% by adding 1.0μg/ml of the extracts from ultra high pressure process in several cancer cell lines such as AGS, Hep3B, MCF-7 and HeLa cells. Among them, MCF-7 cell of the endocrine system was highest inhibited than other cells. The anticancer activities of the extracts from ultra high pressure extraction process showed 10~15%, which was higher than the extracts from normal extraction processes. From HPLC analysis of the extracts, the contents of shikonin in the extracts from ultra high pressure process was 11.42% (w/w), which was 20% higher than others. This results indicate that ultra high pressure process could increase the extraction yield of shikonin and other contents, which resulted in higher anticancer activities.
        167.
        2011.04 KCI 등재 서비스 종료(열람 제한)
        In this study, whitening activity of Lithospermum erythrorhizon extracts were investigated according to several extraction processes: water extraction at 100℃ (WE100) and 60℃ (WE60), 70% ethyl alcohol extraction (EE) and ultra high pressure extraction (HPE) at 500 MPa for 30 minutes at 60℃. The extracts from ultra high pressure extraction showed the highest tyrosinase inhibition and melanogenesis inhibition activities as 52% and 79.5%, respectively, in adding 1mg/ml than others extraction processes. HPE extracts also showed the strong reducing power as 3.19 that absorbance at 450 mm. The contents of polyphenol in WE100, we measured as 10.1μg/ml in adding 1mg/ml. Extracts have a high total flavonoid contents by HPE as 4.1μg/ml at 1mg/ml. We can conclude that better whitening activity of extracts from high pressure extraction was due to high antioxidant activities which could be extracted by higher polyphenol and flavonoid contents in HPE than others.
        168.
        2011.02 KCI 등재 서비스 종료(열람 제한)
        This study was performed to investigate the enhancement of cosmeceutical activities of Berberis koreana bark by different extraction processes. The extracts are WE (water extract at 100℃, control), USE (ultrasonification for 1 hours at 60℃ with water), HPE (high pressure for 5 minutes at 60℃ with water) and USE + HPE (ultrasonification process for 1 hours after high pressure for 5 minutes at 60℃ with water), respectively. The cytotoxicity of the extracts was in the range of 24.02~26.94% at 1.0 mg/ml concentration. The USE + HPE showed the lowest cytotoxicity. Compared to the WE, total phenolic and flavonoid contents in the USE + HPE increased to 121.5% and 154.2%. The USE + HPE showed the highest activity at 1.0 mg/ml concentration in 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging, inhibition activity of xanthine oxidase and superoxide dismutase (SOD)-like test, respectively. Tyrosinase inhibition of WE, USE, HPE and USE + HPE at 1.0 mg/ml concentration was measured as 17.72, 19.62, 22.83 and 24.16%, respectively. Hyaluronidase inhibition activities of the USE + HPE were higher than 20.8%~29.5% of the WE. Our results suggested that the extracts from ultrasonification process after high pressure extraction has relatively high cosmeceutical activities, and that the bark of Berberis koreana could be considered as a candidate of new functional cosmetic agents.
        169.
        2011.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        고추장굴비의 지방산패를 최소화하기 위하여 신선굴비를 동결건조한 굴비포를 사용하여 고추장굴비를 제조하고 비열처리 살균방법으로 초고압과 감마선 처리하여 저장 중에 품질과 미생물변화를 분석함으로서 고추장굴비의 저장과 유통기간 연장 가능성을 검토하였다. 초고압처리(200, 400, 600 MPa) 및 감마선 조사(7, 10, 20, 30 kGy) 후 pH 변화는 유의적으로 차이가 없었으며 20일 동안 상온에서 저장 중에도 시료간의 유의적인 변화를 보이지
        170.
        2010.09 KCI 등재 서비스 종료(열람 제한)
        α-크리스토발라이트 구조의 GaPO4에 대한 고압 x-선 회절 실험을 상온에서 8.9 GPa까지 시행하였다. 정방정계에 속하는 출발결정구조는 1 GPa 이하의 압력에서 회절피크가 분리되는 변화를 보이는데, 아마도 망상구조를 이루고 있는 사면체의 방향성이 압력에 의해 흐트러지면서 상-I'로 상변이가 유도된 것 같다. 압력을 증가시키면, 상-I'는 2 GPa와 3 GPa 사이에서 정방정계에 속하는 고압상(상-III)으로 상변이를 하고 있다. 이 결과는 최근 동일한 시료를 이용하여 얻은 고압실험결과(Ming et al., 2007)와 일치하지 않는다. 최고압력에 도달한 다음, 압력을 대기압으로 내리면 상-III이 그대로 유지되는 것으로 나타났다.
        171.
        2010.08 KCI 등재 서비스 종료(열람 제한)
        The objectives of this study were to compare the antioxidant activities by high pressure extraction of Codonopsis lanceolata from different cultivation areas; Hoeng-sung, Jeju island, and China. Total phenolic acid contents of Hoeng-sung, Jeju, China were estimated as 732.11, 640.25, and 584.85 mg QUR/100 g DW, respectively. The flavonoids contents of Hoeng-sung, Jeju, China were measured as 80.37, 76.46, and 74.55 mg QUR/100g DW, respectively. Generally, contents of phenolic acid and flavonoids, HPE was higher than conventional extraction process. Hoeng-sung Codonopsis lanceolata showed 64.33% of DPPH radical scavenging activity (EDA, %) in 3.2 mg/ml of Hoeng-sung Codonopsis lanceolata. The reducing power of Hoeng-sung cultivation area Codonopsis lanceolata also showed the high activity as 3.15. In generally, antioxidant activities of Codonopsis lanceolata were increased by high pressure extraction process. Based on these results, higher contents of flavonoids and total polyphenols were found extracted by high pressure extraction of Codonopsis lanceolata grow in Hoeng-sung area than others.
        172.
        2010.06 KCI 등재 서비스 종료(열람 제한)
        We investigated a method to improve anticancer activities of Acer mono wood extracts by ultra high pressure extraction process. The A. mono was extracted by water at 40℃ and 300 MPa for 15 min (High Pressure Extraction, HPE). The extraction yield by ultra high pressure extraction process was 5.42%. The cytotoxicity on human normal lung cell (HEL299) of the extracts from HPE showed 21.54% lower than that from conventional water extraction at 100℃ in adding the maximum concentration of 1.0 mg/ml. Ultra high pressure extracts process for 15 minutes extracts (HPE15) showed more potent scavenging effect than the control, BHA. On SOD-like test, the HPE15 showed highest activity as 32.4% at 1.0 mg/ml concentration. Human stomach adenocarcinoma, liver adenocarcinoma, breast adenocarcinoma and lung adenocarcinoma cell growth were inhibited up to about 67~79%, in adding 1.0 mg/ml of extracts from HPE. HPE was 20~25% higher than conventional water extraction. It was interesting that, among several cancer cell lines (stomach adenocarcinoma, liver adenocarcinoma), the growth of digestive related cancer cells were most effectively inhibited as about 75~79%. On in vivo experiment using ICR mice, the variation of body weight of mice group treated A. mono wood extracts from HPE of 100 mg/kg/day concentration was very lower than control and other group. The survival times of group treated this extracts was 61.96% longer than that of the control group and this extracts showed the lower tumor weight, which were 10.49 g than positive control as 16.17 g. Based on these results, we could tell that the HPE wood extracts of A. mono had higher anticancer activity than conventional water extraction. The results of HPE showed obvious advantages in higher efficiency, shorter extraction time, at lower energy costs.
        173.
        2010.04 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        본 연구는 비가열 신선 과채음료 6종에 대한 250~350 MPa 범위의 중고압 처리에 따른 미생물 개체수, 비타민 함량, 관능적 특성 변화 측면에서 권장 유통기간 3일 동안의 품질 안정성 확보 및 유통기간 연장가능성을 검토하였다. 초기 미생물 개체수가 g당 이하로 유지되는 채소 및 과일 원료에 있어서 온도 , 습도 55~60% 가 유지되며, 낙하균과 부유균의 미생물이 각각 CFU/plate, 의 수준으로 관리되는 신선 음료 생산 현장의 경
        174.
        2009.12 KCI 등재 서비스 종료(열람 제한)
        Hepatoprotective and antioxidant activities of Acer mono and A. okamotoanum were compared after beingextracted by low temperature and high pressure (LTHP) at 20 MPa and 60℃ for 15 minutes. Extraction yield of both A.mono and A. okamotoanum was increased about 40~43% by this extraction process. On scavenging activities, the bark of A.okamotoanum from this extraction process showed the highest activity as about 97%. This value was higher than that fromconventional water extraction and A. mono extracts. Both of A. mono and A. okamotoanum showed high ability on nitritescavenging, but decreasing tendency according to increasing of pH. On SOD-like test, A. okamotoanum had the highestactivity as 46.28% at 1.0㎎/㎖ concentration. A. okamotoanum extracted by LTHP also showed the highest activity as197.38% in adding 1.0㎎/㎖ concentration. Generally, the extracts from low temperature and high pressure extraction pro-cess are higher hepatoprotective and antioxidant activities than that from conventional water extraction. It can concludethat the bark of A. okamotoanum has better biological activities than other parts of A. mo
        175.
        2009.12 KCI 등재 서비스 종료(열람 제한)
        The low quality fresh ginseng was extracted by water at 80℃ and 240bar for 20min (HPE, High pressureextraction process). The cytotoxicity on human normal kidney cell (HEK293) and human normal lung cell (HEL299) of theextracts from HPE showed 28.43% and 21.78% lower than that from conventional water extraction at 100℃ in adding themaximum concentration of 1.0㎎/㎖. The human breast carcinoma cell and lung adenocarcinoma cell growth were inhib-ited up to about 86%, in adding 1.0㎎/㎖ of extracts from HPE. This values were 9-12% higher than those from conven-tional water extraction. On in vivo experiment using ICR mice, the variation of body weight of mice group treated freshginseng extracts from HPE of 100㎎/㎏/day concentration was very lower than control and other group. The extracts fromHPE was showed longer survival times as 35.65% than that of the control group, and showed the highest tumor inhibitionactivities compared with other group, which were 70.64% on Sarcoma-180 solid tumor cells. On the high performance liq-uid chromatogram (HPLC), amount of ginsenoside-Rg2, Rg3, Rh1 and Rh2 on fresh ginseng were increased up to 43-183%by HPE, compared with conventional water extracts. These data indicate that HPE definitely plays an important role ineffectively extracting ginsenoside, which could result in improving anticancer activities. It can be concluded that low qualityfresh ginseng associated with this process has more biologically compound and better anticancer activities than that fromnormal extraction process.
        176.
        2009.04 KCI 등재 서비스 종료(열람 제한)
        This study was performed to enhance anticancer activities of E. sinica, and A. gigas by ultra high pressure extraction process. The cytotoxicity of E. sinica and A. gigas on human kidney cell (HEK293) was as low as 24.94% and 25.3% in adding 1.0 mg/ml of the sample extracted at 500 Mpa for 15 minute. Generally, the inhibition of cancer cell growth on A549 and MCF-7 was increased over 20% in the ultra high pressure samples, compared to the conventional extraction process. Under the extracts from ultra high pressure process showed not only the strongest anticancer activities, but also had better stability than normal extracts. It was also found that the extracts of A. gigas reduced the hypertrophy of the internal organs, such as adrenal and spleen caused stresses in several mouse models.
        177.
        2008.12 KCI 등재 서비스 종료(열람 제한)
        This study was performed to investigate a methodology of improving immune activities of Berberis koreana Palibin by ultra high pressure on low temperature extraction process. Extraction yield was enhanced up to more than 35% by above process, compare to the control and extraction average. The cytotoxicity on human kidney cell (HEK293) was showed below 20.4%, 21.6% in adding 1.0 mg/ml of the highest concentration. Generally, the extracts by ultra high pressure extraction process showed less toxicity about 5% than the other processes. It could tell that toxic materials that existing in the plant could be reduced or broken by ultra high pressure process due to can be broken bond such the hydrogen bond, the electrostatic bond, the van der Waals bond, and the hydrophobic bond, can be broken by high pressure. The result could be employed to develop a new type of functional food from B. koreana Palibin by low temperature high pressure process.
        178.
        2008.08 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 초고압 추출 공정의 활성 증진 효과를 알아보기 위해 당귀의 자외선 차단 효과 및 피부 미백활성 실험을 실시하였다. 인간의 섬유아세포인 CCD-986sk를 이용한 세포독성 실험에서 1.0mg/ml 농도의 시료 첨가를 통해 초음파 병행 60℃ 추출물이 21.27%로 가장 낮은 세포독성을 나타내었으며, 15분간 초고압 처리한 60℃초음파 병행 추출물이 23.49%로 가장 높은 세포독성을 나타내었다. UVA 처리에 따른 MMP-1 발현 저해 효과 측정에서 1.0mg/ml 첨가를 통해 15분간 초고압 처리한 60℃ 초음파 추출물이 UV를 조사하지 않은 대조군과 비교하여 122.2%를 나타내며 양성대조군인 ascorbic acid의 121.3%와 근사한 수치의 발현 억제 효과를나타내었다. 그 외 다른 시료들도 134.5% 이하로 발현하며 높은 저해율을 나타냄에 따라 당귀가 UVA에 대한 MMP-1 발현 저해 효과가 있음을 나타내었다. Tyrosinase 억제효과에서는 양성대조군인 ascorbic acid가 1.0mg/ml의 농도에서 70.8%로 가장 높은 저해율을 나타내었다. 당귀 시료 중에서는 초고압을 15분간 처리한 60℃ 초음파 추출물이 ascorbic acid에 근사한 수치인 69.4%로 가장 높은 저해율을 나타내었고, 그외의 시료들도 모두 55% 이상의 높은 저해율을 나타내었다. 시료 첨가를 통한 Clone M-3 세포주의 melanin 생성 억제실험에서 1.0mg/ml 농도 첨가를 통해 15분간 초고압 처리한 60℃ 초음파 추출물이 82.4%를 나타내어 양성대조군인 ascorbic acid에 비해 더 높은 활성을 나타내었다. 이상의 결과를 통하여 당귀가 자외선 차단 및 피부 미백 관련 향장 소재로의 활용 가능성이 있으며, 초고압 처리를 통해 향장활성의 증가가 가능함을 확인하였다.
        180.
        2007.12 KCI 등재 서비스 종료(열람 제한)
        본고에서는 초고압 추출 공정을 통한 홍경천의 독성 저감 및 항암활성 효과를 알아보기 위하여 실험을 실시하였는데 그 결과는 아래와 같다. 인간의 정상 신장세포인 HEK293을 이용한 세포 독성은 초고압으로 15분간 처리한 것에서는 1.0 mg/ml의 농도에서 최고 20.4%의 세포독성을 보였으며, 초고압으로 5분간 처리한 것은 22.5%로 초고압 시간이 길어질수록 세포독성이 낮아지는 것을 확인했다. 일반 추출물은 25.3%로 초고압 처리한 군에 비해 높은 독성을 나타내어 초고압 처리 시 독성이 저감되는 것을 확인하였다. 초고압 처리 군은 또한 HEL299를 이용한 세포독성 실험에서도 1.0 mg/ml의 농도에서 일반 추출물인 WE보다 5% 정도 낮은 독성을 나타냈다. 항암활성 측정은 A549, AGS, MCF-7, Hep3B의 암세포를 실험에 사용하여 실시하였다. 모든 암세포에서 1.0 mg/ml의 농도에서 75% 이상의 높은 억제활성을 보였고, 또한 암세포의 생육활성에 대한 정상 세포의 세포독성의 비로 나타낸 선택적 사멸도는 0.6 mg/ml에서 가장 높은 수치를 보였는데 모두 4이상으로 나타났으며, 15분 동안 초고압 추출을 한 것이 가장 높게 나타났다. 본 실험 결과를 통하여 초고압으로 인해 기존의 추출 방법으로는 추출되지 않았던 유용생리활성 물질들이 초고압으로 인해 조직과 세포막 파괴로 인해용출량 증가로 인해 수율이 증가하였으며, 홍경천의 독성 물질이 파괴되는 것으로 판단된다. 단순한 침전 추출법에 의한 추출방법보다는 초고압 추출에 의한 추출로 식물체에 함유되어 있는 성분 추출의 수율을 배가 시킬 수 있으며, 홍경천 자체 성분에 약간의 변화를 가할 수 있을 것으로 생각된다. 홍경천 성분의 변화는 초고압 추출을 통하여 에너지 수준이 제한된 수소결합, 전기적 결합, 반데르발스결합, 수소결합과 같은 약한 결합들이 분리됨으로써 성분의 변화가 있을 것으로 보인다.
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