본 연구에서는 편백나무 잎 추출물의 에틸아세테이트 분획을 함유한 크림의 안정성을 평가하였다. 다양한 저장 온도(4℃, 25℃, 37℃ 및 45℃) 및 태양광선에의 노출 하에서 12주 동안 추출물 함유 크림의 pH, 점도 및 흡광도 변화를 측정하였다. 위에서 언급된 온도별 저장조건에서 추출물이 함유되어 있지 않은 대조군 크림은 pH 변화가 거의 없었다. 추출물 함유 크림의 경우는 4℃와 25℃에서 pH가 평균 0.11 감소하였고, 37℃, 45℃ 저장과 태양광선 노출 시는 각각 0.55, 0.84 및 0.59 감소하였다. 온도별 저장 조건에서 12주 후 추출물 함유 크림과 대조군 크림의 점도를 측정하였다. 추출물 함유 크림은 초기 점도보다 평균 2,404 cPs 감소를 나타내었고, 대조군은 평균 1,296 cPs 감소하였다. 45℃ 조건에서 대조군은 12주 후 점도가 1,915 cPs로 감소되었지만, 동일 조건에서 추출물 함유 크림의 점도는 3,810 cPs 감소하였다. 12주 동안 4℃~37℃에서 추출물 함유 크림의 흡광도 변화는 거의 없었다. 반면에 45℃ 저장과 태양광선 노출시킨 경우는 흡광도는 각각 32.5 % 및 35.2 % 감소하였다. 크림으로부터 추출물을 용출시킨 에탄올 용액을 태양광선에 직접 노출시켰을 때 4주 만에 흡광도가 54.8 %감소한 것에 비해서는 작은 감소를 나타낸다. 이는 추출물크림이 크림 내에서 비교적 안정화되어 있음을 나타낸다. 추출물 함유 크림과 대조군 크림은 12주 동안 동일한 실험 조건에서 변취나 변색이 나타나지 않았으며, 크리밍이나 응집과 같은 현상은 관찰되지 않았다. 이러한 결과들로부터 편백나무 잎 추출물을 함유한 크림이 비교적 안정함을 확인하였다. 하지만, 추출물 함유 크림을 장기간 저장할 때 안정성은 아직 확실치는 않으며, 추출물을 화장품에 응용하기 위해서는 더 많은 연구가 필요하다고 사료된다.

In this study, the antioxidative effects and inhibitory effects on tyrosinase and elastase of Sorbus commixta (S. commixta) twig extracts were investigated. The aglycone fraction of S. commixta twig extract showed the prominent free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activity(FSC50, 13μg/mL). Reactive oxygen species (ROS) scavenging activities of S. commixta twig extracts on ROS generated in Fe3+-EDTA/H2O2 system were investigated by the luminol-dependent chemiluminescence assay. The 50 % ethanol extract among extracts showed the most prominent ROS scavenging activity (OSC50, 0.189μg/mL). The cellular protective effects of extract/fractions of S. commixta twig on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The 50 % ethanol extract and ethyl acetate fraction showed the cellular protective effects against ROS in a concentration dependent manner (5~50μg/mL). The inhibitory effect of S. commixta twig extract on tyrosinase was investigated to assess the whitening efficacy. The ethyl acetate (IC50, 113.2μg/mL) and aglycone fraction(IC50, 105.3μg/mL) on tyrosinase showed more remarkable inhibitory effect than arbutin(IC50, 226.88μg/mL), known as the whitening agent. The inhibitory effect of aglycone fraction (IC50, 6.9μg/mL) on elastase was simillar to quercetin(IC50, 6.1μg/mL), flavonoid known as reference compound. These results indicate that extract/fractions of S. commixta twig can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging 1O2 and other ROS, and protect cellular membranes against ROS. S. commixta twig extracts can be applicable to new functional cosmetics for anti-aging products.

In this study, the antioxidative effect, cellular protective effect and inhibitory effect on tyrosinase of Cosmos bipinnatus extracts were investigated. The ethyl acetate fraction of Cosmos bipinnatus flower extract (11.48 μg/mL) showed more excellent free radical (1,1-diphenyl-2-picrylhydrazyl radical, DPPH) scavenging activity (FSC50) than those of leaf and stem extracts (17.45 μg/mL). Reactive oxygen species (ROS) scavenging activity (OSC50) of Cosmos bipinnatus extracts on ROS generated in Fe3+-EDTA/H2O2 system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction of Cosmos bipinnatus flower extract (0.56 μg/mL) showed 3 times more excellent ROS scavenging activity than L-ascorbic acid (1.50 μg/mL). The protective effects of the ethyl acetate fractions of extracts from different parts of Cosmos bipinnatus on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fractions of leaf and stem extract and flower extracts suppressed photohemolysis in a concentration dependent manner (10~50 μg/mL). The inhibitory effect of ethyl acetate fraction of Cosmos bipinnatus flower extract (62.75 μg/mL) on tyrosinase was investigated to assess the whitening efficacy. The ethyl acetate fraction of Cosmos bipinnatus flower extract showed 3.5 times higher tyrosinase inhibitory effect than arbutin (226.88 μg/mL) known as an effective whitening agent. These results indicate that fractions of Cosmos bipinnatus extracts can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging 1O2 and other ROS, and protect cellular membranes against ROS. Fractions of Cosmos bipinnatus extracts can be applicable to new functional cosmetics for antioxidant and whitening.

In this study, the anti oxidative effects, inhibitory effects on elastase, and components of Securinega suffruticosa extracts were investigated. The free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities (FSC50) and reactive oxygen species ROS) scavenging activities (OSC50) of extract/fractions from Securinega suffruticosa were measured. The aglycone fraction (9.04 ± 0.51 μg/mL) and 50 % ethanol extract (1.05 ± 0.41 μg/mL) showed the most effective scavenging activities. The protective effects on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The aglycone fraction exhibited the most prominent cellular protective effect (τ50, 102.77 ± 5.37 min at 10μg/mL). The inhibitory effect of ethyl acetate fraction on tyrosinase were of examined (210.0 ± 1.02 μg/mL). The inhibitory effect of aglycone fraction on elastase were also investigated (17.6 ± 1.26 μg/mL). These results indicate that extract/fractions of Securinega suffruticosa can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging 1O2 and other ROS, and protect cellular membranes against ROS. Securinega suffruticosa extract could be used as a new cosmeceutical ingredient for whitening and anti-wrinkle products.

Caprylic/Capric triglyceride-in-water emulsions stabilized by Nikkol HCO-60 and HCO-10 were prepared using emulsion inversion point method at different HLB values. Emulsions with various droplet sizes were formed, and emulsion inversion point was detected by electrical conductivity. The change in emulsion droplet sizes and long term stability were monitored using laser scattering method and visual method. The droplet sizes and stability of emulsions were affected by HLB of surfactant. At emulsion inversion point, the water volume fraction increased as the HLB of surfactants decreased. According to our analysis, this resulted from a tendency of forming the W/O (water-in-oil) emulsion as the HLB of surfactants was decreased. The emulsion inversion point was clearly detected by the microscope and the electric conductivity meter. Nanometer-sized emulsion was obtained at the optimum HLB by using emulsion inversion point method. The main pattern of instability of emulsions in HLB 12 and 13 systems was Ostwald ripening. However, The patterns of instability of emulsions below 11 of HLB systems were Ostwald ripening and coalescence. All emulsions produced with surfactants in the range of HLB 8-13, creaming caused by density difference between water phase and oil phase.

컨테이너 물동량 증가와 함께 선박의 대형화는 항만과 터미널 운영에 많은 영향을 주었고, 선사들의 운송네트워크들은 점차 hub-and-spoke방식으로 변하고 있다. 이는 항만간 치열한 경쟁을 초래하였고 그로 인해 새로운 항만을 개발하거나 기존 항만을 확장해야 하는 압력들을 받아왔다. 그러나 항만 개발에 따른 환경적 물리적 재무적 한계를 극복하기에는 너무나 많은 비용과 시간의 투자를 요구하고 있다. 그래서 본 연구에서는 하나의 대안으로서 새로운 해상 운송시스템인 모바일하버를 다루었다. 그리고 컨테이너 연안운송시장을 중심으로 모바일하버 도입에 대한 경제적 분석과 함께 관련 요인들의 변화들에 대한 민감도 분석도 같이 수행하였다. 본 연구는 모바일하버의 가치와 활용방안에 대한 기초 연구로서 추후 관련 연구들에 대해 기여하고자 하였다.

컨테이너항만의 물동량 예측은 항만의 개발 및 운영계획을 위해 매우 중요한 과정이다. 일반적으로 회귀분석, ARIMA모형 등의 통계적 방법론을 통해 많은 예측이 이뤄져왔다. 최근의 연구에서는 인공 신경망(ANN)기법을 통한 예측이 이뤄지고 있으며 기존의 선형적인 기법을 대신하고 있다. 본 연구에서는 선형모형과 비선형모형에 강점이 있는 ARIMA모형과 신경망모형을 결합해 보다 효과적인 예측 모형을 개발하고자 한다. 실제 항만의 과거 자료를 통해 모델의 적합성을 측정하였고 항만의 특성에 따라 모형의 적합성이 다양하게 나타났다.