본 연구는 은행 열매 오일의 멜라닌 생성 억제 효과를 확인한 것이다. 은행나무 열매 오일은 DPPH assay와 FRAP assay를 사용하여 라디컬 소거능을 시험하였다. 결과적으로 은행나무 열매 오일은 DMSO를 용매 로 0.06% 녹였을 때, DPPH assay에서 9.96% 소거활성을 나타내었고 FRAP는 1.33 mM의 ferric sulfate (FeSO4)를 생성하였다. 은행 열매 오일은 tyrosinase inhibition assay에서 37.72%의 억제력을 가졌고 B16/F10 세포에 멜라닌 생합성 실험을 통해 확인하였다. 은행 오일 0.06%에서 α-MSH 처리 구에 비해 48.02%의 멜라닌 생성을 억제하였다. Tyrosinase, tyrosinase related protein-1 (TRP-1), tyrosinase related protein-2 (TRP-2), microphthalmia-associated transcription factor (MITF)의 유전자 발현 수 준은 control군에 비해 0.04%와 0.06% 농도 군이 크게 감소하였다. 결과적으로 은행 열매 오일 추출물이 멜라 닌 생성을 억제하는 효과가 있는 것으로 확인되었다.

The environmental changes related to hypoxic water mass were investigated at Gamak bay in summer times, June, July and August 2006. The hypoxic water mass was found, in first, at the northern area of Gamak bay on 27 June. This water mass has been sustained until the end of August and disappear on 13 September. In Gamak bay, the hypoxic water mass was closely related to geography. During the formation of oxygen deficiency, changes in dissolved nutrients was studied and found that on surface layer and lower layer, DIN were 0.80 μM~19.8 μM(6.03 μM) and 1.13 μM～60.83 μM(10.66 μM), and DIP were 0.01 μM～0.92 μM(0.24 μM), and 0.01 μM～3.57 μM(0.49 μM), respectively, far higher distribution on lower layer of the water where hypoxic water mass was occurred. The configuration of phosphorus was analyzed to figure out the possibility of release of phosphorus from sediments. It was found that the Labile-Phosphorus, which is capable of easy move to water layer by following environmental change was found more than 70%. Therefore, in Gamak bay, it was found that the possibility of large amount of release of soluble P into the water, while hypoxic water mass was occurred in deep layer was higher. It is suggested that DIP in the northern sea of Gamak bay mainly sourced from the soluble P from lower layer of the waters where hypoxic water mass was created more than that from basin. However, existence form of phosphorus in sediments during normal times, not during creation of hypoxic water mass, needs further study.

Harmful dinoflagellate Cochlodinium polykrikoides blooms have been frequently occurred in coastal areas of the East Sea since 1995. We compared the oceanic conditions in years 1995, 2001 and 2003 when the C. polykrikoides bloom was strong, and in years 1998 and 2004 when the C. polykrikoides bloom was not appeared. We studied temporal and spatial variation of upwelling and geostrophic currents on the western channel of Korean Strait, an entrance of the East Sea. The period and occurrence area of C. polykrikoides bloom was depended on variation of upwelling in summer. In the distributions of geostrophic current, southward current was dominant near the coast in August, 1998 and 2000. Whereas northward current was dominant near and off the coast in August, 1995 and 2003 which the C. polykrikoides bloom was strong. When compared dominant phytoplankton of the coastal areas in each year, Kuroshio indicator species Proboscia alata and Chaetoceros affine were dominant, respectively, in 2001 and 2003 at every stations. However, the dominant species was variable at each coastal area in 1998 and 2000. In 2003, the abundance of Sagitta elegans which is known as the cold water indicator was low, but the abundance of S. enflata, warm water indicator, was very high in Gangneung compared to Sokcho. It seemed that the distribution of S. elegans is restricted by strong warm water current. In conclusion, it was estimated that the distribution of C. polykrikoides bloom in the coastal area of the East Sea was closely related with the strength of East Korea Warm Current and upwelling.

여드름 완화 효과를 갖는 천연 약용식물 추출물을 개발하기 위하여 여드름 원인균에 대한 항균 활성 및 항염증 효과를 다양한 추출물을 대상으로 분석하였다. 검색 결과 얻어진 후보 소재들 중, 비교적 높은 항균 활성을 갖는 보골지,당후박과 항염증 효과를 갖는 목향, 구절초 추출물을 대상으로 선정하였고 이후의 실험을 진행하였다. 보골지(Psoralea corylifolia L., AC-1), 당후박(Magnoliae officinalis, AC-2), 목향(Inula helenium L., ACF-1), 구절초(Chrysanthemum zawadskii var. latilobum, ACF-2) 추출물 및 복합소재(AC)는 50 μg/mL 이하에서 세포 독성이 없는 것으로 확인되었다. 보골지, 당후박 추출물 및 복합소재의 경우 여드름 유발 원인균인 Propionibacterium acnes (P. acnes)에 대해 양성 대조군으로 사용한 10 % salicylic acid 대비 각각 약 2.8배, 2.5배, 3.2배의 높은 항균 효과를 보였다. 또한 Staphylococcus aureus (S. aureus)에 대해서도 당후박 추출물과 복합소재의 경우 양성 대조군으로 사용한 10 % Methylparaben 대비 각각 약 1.4배, 1.5배 높은 항균 효과를 보였다. 목향, 구절초 추출물 및 복합소재의 경우 열에 의해 사멸시킨 P. acnes에 의해 활성화된 THP-1 세포의 IL-8 발현을 50 μg/mL 농도에서 각각 27 %, 38 %, 44 % 저해하였고 TNF-α 발현을 50 μg/mL 농도에서 각각 90 %, 88 %, 90 %로 크게 저해하였다. 이러한 항균, 항염증 활성을 보이는 보골지, 당후박, 목향, 구절초 추출물의 복합 소재를 이용하여 여드름 완화 효과를 갖는 화장품으로의 개발이 가능할 것으로 보인다.

멜라닌 생합성을 활성화하여 자연스러운 모발의 흑화를 촉진할 수 있는 소재를 개발하기 위하여 음양곽 메탄올 추출물의 멜라닌 생성에 연관된 생리 활성을 분석하였다. 음양곽 추출물은 100 µg/mL 이하에서 세포 독성이 없는 것으로 확인 되었으며 50 µg/mL 농도에서 B16 melanoma 세포 내 멜라닌 생합성을 104 % 증가시켰고 tyrosinase의 활성을 95 % 촉진하는 것으로 나타났다. Western blot을 이용한 실험에서는 음양곽 추출물이 농도 의존적으로 TRP-2의 발현을 증가시키는 경향을 관찰할 수 있었다. 또한 C3H/Hej 마우스를 이용한 동물 실험에서 음양곽 추출물을 도포한 등 부위 털의 멜라닌 생합성이 5 % (w/v) 도포 시 25 % 증가되는 경향을 관찰할 수 있었다. 위의 결과를 통해 음양곽 메탄올 추출물이 멜라닌 생합성 기전에 관여하는 것으로 알려진 tyrosinase의 활성 촉진, 멜라닌 생합성 기전과 melano-cyte 생존에 관여하는 것으로 알려진 TRP-2의 발현 증가를 통해 멜라닌 합성 촉진을 유도하는 것으로 추측해 볼 수 있었다. 이러한 음양곽 추출물의 효능을 이용해 모발의 흑화 촉진 효과를 나타내는 화장품 소재 개발이 가능할 것으로 보인다.

Eco-physiological research and the control of Cochlodinium polykrikoides was carried out to elucidate eco-physiological characteristics of red tide organism through culture experiment depending on the condition of photon irradiance. Oxygen consumption of C. polykrikoides was high with a value of 1.12mg/L/hr in the dark compared with that of 0.13mg/L/hr at 100μEm-2s-1. DO values in a circular chamber with the lapse of time in seawater containing C. polykrikoides were declined in the dark period. DO values of seawater containing C. polykrikoides in the dark were declined from 7.01mg/L to 2.65mg/L in 30cm depth and from 7.01mg/L to 6.63mg/L in 5cm depth depending on the depth of circular culture vessel. Olive flounder, Paralichthys olivaceus and file fish, Stephanolepis cirrhifer exposed to Cochlodinium showed the separation of the lamella epithelium from gill filament, which disrupted the respiratory process at the gill level.

천연 미백 소재 개발을 위하여 복령피 추출물과 복령피 추출물에서 분리한 활성 물질의 멜라닌 생성에 연관된 생리 활성을 분석하였다. 복령피 추출물은 100 µg/mL 이하에서 세포 독성이 없는 것으로 확인 되었으며 free radical 소거능(DPPH)과 superoxide radicals 소거능 결과는 각각 IC50 = 19.4 ± 2.21 µg/mL, IC50 = 103 ± 3.33 µg/mL을 나타내었다. 50 µg/mL 농도에서 B16 melanoma 세포 내 tyrosinase의 활성을 34 % 저해 하였으며, 세포 내 멜라닌 생합성 저해 효과는 50 µg/mL 농도의 복령피 추출물을 72 h 동안 처리한 세포에서 51 % 억제율을 보이는 것으로 나타났다. 이러한 복령피 추출물의 활성 물질을 분리하여 1H-NMR, 13C-NMR, Mass analysis 등의 기기 분석을 실시한 결과 triterpene류의 3-β-hydroxylanosta-7,9(11),24-trien-4-oic acid로 동정되었고 100 µg/mL 이하에서 세포 독성이 없는 것으로 확인 되었다. 3-β-hydroxylanosta-7,9(11),24-trien-4-oic acid의 free radical 소거능과 superoxide radicals 소거능 결과는 각각 IC50 = 4.3 ± 0.15 µg/mL, IC50 = 54 ± 1.67 µg/mL을 나타내었다. 10 µg/mL 농도에서 세포내 ty-rosinase의 활성을 43 % 저해하였으며, 멜라닌 저해 효과를 확인한 결과 IC50 = 3.6 µg/mL으로 나타났다. Western blot을 이용하여 tyrosinase, tyrosinase related protein-1 (TRP-1), TRP-2 단백질의 발현 감소를 확인하였다. 복령피 추출물과 3-β-hydroxylanosta-7,9(11),24-trien-4-oic acid는 우수한 미백 효능을 갖는 화장품 소재로의 개발 가능성이 클 것으로 기대된다.

본 연구는 천연 미백소재 개발을 위하여 광곽향 추출물과 광곽향 추출물에서 분리한 활성물질의 멜라닌 생성에 연관된 생리활성을 분석하였다. 광곽향 추출물은 100 µg/mL 이하에서 세포 독성이 없는 것으로 확인되었으며 free radical 소거능(DPPH)과 superoxide radical 소거능 결과는 각각 IC50 = 24.2 ± 2.85 µg/mL, IC50 = 118 ± 0.43 µg/mL을 나타내었다. B16 melanoma 세포에서의 멜라닌 생합성 저해 효과는 20 µg/mL 농도의 광곽향 추출물을 72 h 동안 처리한 세포에서 멜라닌 억제율이 23 %로 나타났으며, 50 µg/mL 농도에서 세포 내 tyrosinase의 활성을 18 % 저해하였다. 이러한 광곽향 추출물의 활성물질을 분리하여 1H-NMR, 13C-NMR, Mass analysis 등의 기기분석을 실시한 결과 sesquiterpene 계열의 활성물질인 patchouli alcohol으로 동정되었고, patchouli alcohol의 free radical 소거능과 superoxide radical 소거능 결과는 각각 IC50 = 3.14 ± 0.12 µg/mL, IC50 = 49 ± 3.24 µg/mL을 나타내었다. 또한 멜라닌 저해효과를 확인한 결과 IC50 = 3.9 µg/mL으로 나타났으며, 10 µg/mL 농도에서 세포 내 tyrosinase의 활성을 40 % 저해하였다. Western blot을 이용하여 tyrosinase와 tyrosinase related protein-2 (TRP-2) 단백질의 발현 감소를 확인하였다. 그러므로 광곽향 추출물과 patchouli alcohol은 우수한 미백 효능을 갖는 화장품 소재로서 개발 가능성이 클 것으로 기대된다.

Wangdol-cho, located 23 km offshore of Hupo in southwest of East Sea, is underwater rock floor, called to Wangdol-Am or Wangdol-Jam and has three tops as Mat-Jam, Middle-Jam and Set-Jam. The composition, abundance, diversity and community structure were investigated in winter and summer in 2002 around Wangdol-cho. The temperature around the Northwest and Southeast part of Wangdol-cho was influenced by the North Korea Cold Current (NKCC) and East Korea Warm Current (EKWC), respectively. Nutrient and chlorophyll-a concentration were higher at the top of Wangdol-cho than other area. A total of 41 genera and 78 species of phytoplankton were identified. The average cell abundance of phytoplankton in winter and summer were 286×103 cells/㎥, 432×103 cells/㎥ respectively. The largest community was Bacillariophyta containing 52 taxa. The dominant species were Lauderia anulata and Coscinodiscus spp. which preferred cold water in winter. In contrast, warm water species such as Rhizosolenia stolterfothii and Ceratium spp. were dominant in summer. The average species diversity index of phytoplankton in winter was higher than that in summer. According to dominant species and standing crops, phytoplankton community resulted in a clear separation. One group was western area, which showed low density, and the other was eastern area, which showed the higher density. The abundance and species composition of phytoplankton were affected by topological characteristics around Wangdol-cho.

The seasonal variations of picoplankton including Prochlorococcus, Synechococcus and Picoeukayotes around Ulneung Island were investigated by flow cytometry in spring, summer and autumn in 2006. All groups of picoplankton showed clear seasonal patterns in population abundance. Among the group, Synechococcus showed the most prominent seasonal variation during the study period. The maximal abundance of Synechococcus occurred in summer and the lowest in autumn. The seasonal distribution of Prochlorococcus displayed the reverse tendency with that of Synechococcus. The abundance of Prochlorococcus ranged from 2.9×103 cells/ml in summer to 311×103 cells/ml in autumn. However, the seasonal distribution of Picoeukaryotes was shown to be relatively constant, and the maximal abundance was 81.5×103 cells/ml in summer. The highest abundance of Picoeukaryotes occurred in summer and the lowest in autumn and the seasonal distribution in abundance of Picoeukaryotes showed a similar trend with that of Synechococcus. The estimated total carbon biomass of picoplankton were ranged from 74.7 mgC/m2 to 1,055.9 mgC/m2. The highest total carbon biomass occurred in summer, but lowest occurred in autumn. The pattern of the contribution of three picoplankton to total autotrophic picoplankton carbon is different. The contribution of Synechococcus to total autotrophic picoplankton carbon is increased to 75%, but the contribution of Prochlorococcus dropped to 12% in summer. The contribution of Picoeukaryotes is ranged from 24% in summer to 72.5% in spring.

In order to study the temporal variations of nutrients and chlorophyll-a in the Bottol Bada, three field observations were carried out on 20, 23 and 26 July, 2004. The low N:P values exhibit nitrogen deficiency during the periods of observation. This result is not representative of typical summer environment in the southern coast of Korea. The possible mechanisms are as follows: 1) The freshwater inflow was not sufficient for the supply of nitrogen because the total precipitation was 11.9 mm in July, 2004. This amount is no more than 5% in normal precipitation in July. 2) There was an inflow of oceanic water under the subsurface into the Bottol Bada. Even though the oceanic water comprises more nutrients, it produces the stratification between the surface and the subsurface water and seems to prevent the supply of nutrinets to the surface layer. 3) The high chlorophyll-a concentration of 1.2 μg/L was shown near the narrow channel between Gae-do and Geumo-do. This seems to be resulted from the inflow of water from Gamak Bay.

Based on the observation on 20, 23 and 26 July 2004, the distributions of temperature, salinity and stratification was investigated in relation to ebb, turn of tide and flood. The results are as follows: 1) The high temperature and low saline water with 23.5～24.0℃ and 32.4～33.0psu existed at Naro Island. 2) The cold surface water below 21.0℃ and 33.0～33.4psu appeared in the area near Gae Island and Geumo Island. 3) The cold and saline water, below 24.0℃ at the surface and 17.0℃ near the bottom, 32.8～33.8psu at the surface and 33.8～34.0psu near the bottom, existed in Sori Island. These waters were more saline compared to the South Sea Coastal Water with about 31.8psu. This suggests that the oceanic saline water intruded into the Bottol Bada through the area near Sori Island. The stratification appeared during all the observation periods due to a high solar radiation of 22MJ/m2, and a weak wind speed of 2.9m/s on the average while the mean speed of wind in July is around 3.9 m/s. It qualitatively suggested that the stratification was maintained during the observation periods because of a high solar radiation, a weak wind speed and intrusion of saline oceanic water.

We have studied the catalytic combustion of soot particulates over perovskite-type oxides prepared by malic acid method. The catalysts were modified to enhance the activity by substitution of metal into A or B site of perovskite oxide. In addition, the reaction conditions such as temperature and O2 concentration were investigated. The partial substitution of alkali metals into A site in the LaMnO3 catalyst, enhanced the catalytic activity in the combustion of carbon particulate and the activity was shown in the order: Cs＞K＞Na. For the La1-xCsxMnO3 catalysts, the catalytic activity showed the maximum value with x=0.3 but no more increase on the catalytic activity was shown with x＞0.3. For the La0.8Cs0.2MnO3 catalyst, the substitution of Fe or Ni increased the ignition temperature. The ignition temperature decreased with an increase of O2 concentration, however, no more increase in the catalytic activity was shown with O2 concentration＞0.2. The introduction of NO into reactants showed no effect on the catalytic activity.