• Korean Journal of Pharmacognosy
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• v.17 no.1
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• pp.19-22
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• 1986

As a continuation of the previous work, a second group of sixty solvent fractions prepared from twenty plant species were screened for their inhibitory effects on adenosine 5'-diphosphate (ADP)-, arachidonic acid (AA)- or collagen-induced rat platelet aggregation. The results suggested that five plant species including Angelica koreana, Cassia obtusifolia, Gastrodia elata, Paeonia lactiflora and Salvia miltiorrhiza are potential sources of inhibitors of platelet aggregation.

• Journal of Marine Bioscience and Biotechnology
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• v.1 no.4
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• pp.225-231
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• 2006

The secondary metabolites from Taiwanese marine soft corals and sponges have attracted much attention because they possess considerable potential biological activities. To explore the origin of bioactivity, many cytotoxic natural products were isolated and characterized in the past few years. For examples, The lipophilic extracts from marine sponges Petrosia elastica and Ircinia formosana were found active against several human tumor cells. The investigation of the gorgonian Junceela has also resulted in the discovery of a series of new juncenolides. Bioassay-directed fractionation of Clavularia viridis yielded seven new prostanoids. These compounds have been tested and evaluated as potential antitumor agents. The soft corals of the genus Cespitularia produced novel secondary metabolites with diverse chemical structures and interesting biological activities. Four new norditerpenoids, designated cespitulactones and cespihypotins were isolated from Cespitularia hypotentaculata. Cespitulactones are novel structures having a bond cleavage between C-10 and C-11. In addition, three novel diterpenes were isolated from C. taeniata and designated cespitulactams A, B and C having a phenylethyl amino side chain.

• Journal of Integrative Natural Science
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• v.4 no.4
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• pp.255-265
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• 2011

Marine ecosystems are often characterized by a high biological diversity, and it corresponds to a high chemical diversity. Up to present, more than 20,000 new bioactive substances have been isolated from marine organisms, where considerable numbers of these naturally occurring derivatives are developed as potential candidates for pharmaceutical application. In this process, screening of natural products from marine organisms that could potentially inhibit the expression of metalloproteinases has gained a huge popularity. Cancer is considered as one of the deadliest diseases in the medical field. Matrix metalloproteinase (MMPs) can degrade extracellular matrix (ECM) components and play important roles in a variety of biological and pathological processes. Matrix metalloproteinase inhibitors (MMPIs) have been identified as potential therapeutic candidates for metastasis, arthritis, chronic inflammation and wrinkle formation.

• Journal of KSNVE
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• v.4 no.2
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• pp.137-146
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• 1994

An analytical method for linear free vibration of fully liquid-filled circular cylindrical shell with various boundary conditions is developed by the Fourier series expansion based on the Stokes' transformation. A set of modal displacement functions and their derivatives of a circular cylindrical shell is substituted into the Sanders' shell equations in order to explicitily represent the Fourier coefficients as functions of the end point displacements, forces, and moments. For the vibration relevant to the liquid motion, the velocity potential of liquid is assumed as a sum of linear combination of suitable harmonic functions in the axial directions. The unknown parameter of the velocity potential is selected to satisfy the boundary condition along the wetted shell surface. An explicit expression of the natural frequency equation can be obtained for any kind of classical boundary conditions. The natural frequencies of the liquid-filled cylindrical shells with the clamped-free, the clamped-clamped, and the simply supported-simply supported boundary conditions examined in the previous works, are obtained by the analytical method. The results are compared with the previous works, and excellent agreement is found for the natural frequencies of the shells.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.956-960
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• 2011

The objective of this investigation was to develop nanostructured lipid carriers (NLCs) of tacrolimus by the hot homogenization technique by sonication. NLCs are commonly prepared by emulsification and lyophilization. The feasibility of fabricating tacrolimus-loaded NLCs was successfully demonstrated in this study. The developed NLCs were characterized in terms of their particle size, zeta potential, entrapment efficiency (EE) of tacrolimus, and morphology. Studies were conducted to evaluate the effectiveness of the NLCs in improving the penetration rate through hairless mouse skin. Tacrolimus-loaded NLCs were found to have an average size of $123.4{\pm}0.3\;nm$, a zeta potential of $-24.3{\pm}6.2\;mV$, and an EE of 50%. In vitro penetration tests revealed that the tacrolimus-loaded NLCs have a penetration rate that is 1.64 times that of the commercial tacrolimus ointment, Protopic$^{(R)}$.

• Journal of Food and Nutrition Research
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• v.9 no.1
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• pp.26-31
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• 2021

Functional food ingredients from natural sources are gaining popularity for treating chronic inflammation associated with metabolic diseases (e.g., diabetes, hypertension, and obesity) due to their lower toxicity and no severe side effects. Pigmented rice is a natural food source in Korea commonly consumed in the whole grain form to improve the immune system. In particular, pigmented rice bran contains various nutritional components involved in the immune benefits. Of many nutrients in pigmented rice bran, anthocyanins, gamma-oryzanol, and arabinoxylan have notably shown to enhance natural killer cell activity and reduce pro-inflammatory cytokines. Especially, pigmented rice has higher amounts of anthocyanins and gamma-oryzanol than white rice. In this review, to provide further insight into the immune effects of the pigmented rice, we have focused on the immune benefits of bioactive substances (e.g., anthocyanins, gamma-oryzanol, and arabinoxylan) from pigmented rice compared to white rice. The pigmented rice has potential effects on immunity, and it can be used as a functional food.

• Proceedings of the KSEEG Conference
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• 2002.06a
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• pp.81-100
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• 2002

While most of regulatory communities in abroad recognize ' 'natural attenuation " to include degradation, dispersion, dilution, sorption (including precipitation and transformation), and volatilization as governing Processes, regulators prefer "degradation" because this mechanism destroys the contaminant of concern. Unfortunately, true degradation only applies to organic contaminants and short- lived radionuclides, and leaves most metals and long-lived radionuclides. The natural attenuation Processes may reduce the potential risk Posed by site contaminants in three ways: (i)contaminants could be converted to a less toxic form througy destructive processes such as biodegradation or abiotic transformations; (ii) potential exposure levels may be reduced by lowering concentrations (dilution and dispersion); and (iii) contaminant mobility and bioavailability may be reduced by sorption to geomedia. In this review, authors will focus will focul on "sorption" among the natural attenuation processes of hazardous inorganic contaminants including radionuclides. Note though that sorption and transformation processes of inorganic contaminants in the natural setting could be influenced by biotic activities but our discussion would limit only to geochemical reactions involved in the natural attenuation. All of the geochemical reactions have been studied in-depth by numerous researchers for many years to understand "retardation" process of contaminants in the geomedia. The most common approach for estimating retardation is the determination of distrubution coefficiendts ($K_{d}$) of contaminants using parametric or mechanistic models. As typocally used in fate and contaminant transport calculations such as predictive models of the natural attenuation, the $K_{d}$ is defined as the ratio of the contaminant concentration in the surrounding aqueous solution when the system is at equilibrium. Unfortunately, generic or default $K_{d}$ values can result in significant error when used to predict contaminant migration rate and to select a site remediation alternative. Thus, to input the best $K_{d}$ value in the contaminant transport model, it is essential that important geochemical processes affecting the transport should be identified and understood. Precipitation/dissolution and adsorption/desorption are considered the most important geochemical processes affecting the interaction of inorganic and radionuclide contaminants with geomedia at the near and far field, respectively. Most of contaminants to be discussed in this presentation are relatively immobile, i.e., have very high $K_{d}$ values under natural geochemical environments. Unfortunately, the obvious containment in a source area may not be good enough to qualify as monitored natural attenuation site unless owner demonstrate the efficacy if institutional controls that were put in place to protect potential receptors. In this view, natural attenuation as a remedial alternative for some of sites contaminated by hazardous-inorganic components is regulatory and public acceptance issues rather than scientific issue.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.5
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• pp.589-601
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• 2014

Natural gas hydrate (NGH) is emerging as a new eco-friendly source of energy to replace fossil fuels in the 21st century. It is well known that the Natural Gas Hydrate contains large amount of natural gas about 170 times as much as its volume and it is easy to be stored and transported safely at about $-20^{\circ}C$ under atmospheric pressure due to so called "self-preservation effect". The option of gas transport by gas hydrate pellets carrier has been investigated and developed in various industry and academy. The natural gas hydrate pellet carrier is on major link in a potential gas hydrate process chain, starting with the extraction of natural gas from the reservoir, followed by the production of hydrate pellets and the transportation to an onshore terminal for further processing or marketing. In recent years, Korean project team supported by Korean Government has been working on the development of NGH total systems including novel NGH carrier since 2011. In order to increase the knowledge on the NGH pellet carrier developed and to understand the major hazards that could have significant impact on the safety of the vessel, this paper presents and evaluates the pros and cons of cargo holds, loading and unloading systems through the analysis of current patent technology. Based on the proven and well-known technologies as well as potential measures to mitigate sintering and minimize mechanical stress on the hydrate pellet in the self-preservation state, this study presents the conceptual and basic design for NGH carrier.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.50-57
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• 2012

Phospholipase C-${\gamma}l$ (PLC-${\gamma}l$) expression is associated with cellular transformation. Notably, PLC-${\gamma}$ is up-regulated in colorectal cancer tissue and breast carcinoma. Because exotoxins released by Clostridium botulinum have been shown to induce apoptosis and promote growth arrest in various cancer cell lines, we examined here the potential of Clostridium difficile toxin A to selectively induce apoptosis in cells transformed by PLC-${\gamma}l$ overexpression. We found that PLC-${\gamma}l$-transformed cells, but not vector-transformed (control) cells, were highly sensitive to C. difficile toxin A-induced apoptosis and mitotic inhibition. Moreover, expression of the proapoptotic Bcl2 family member, Bim, and activation of caspase-3 were significantly up-regulated by toxin A in PLC-${\gamma}l$-transformed cells. Toxin A-induced cell rounding and paxillin dephosphorylation were also significantly higher in PLC-${\gamma}l$-transformed cells than in control cells. These findings suggest that C. difficile toxin A may have potential as an anticancer agent against colorectal cancers and breast carcinomas in which PLC-${\gamma}l$ is highly up-regulated.

• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.647-650
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• 2014