• Journal of The Korean Association For Science Education
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• v.20 no.4
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• pp.582-598
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• 2000

There are many bioethical issues in line with the rapid advance of biology. In this situation, it is important for students to make a rational decision on value problem. In this study 'value inquiry in biology education' is defined as 'the process of rational value judgement and wise decision-making in the biology-related value problem' and the model was developed. To develop the model, value inquiry models were reviewed. Value clarification model is helpful for the formation of the personal value as the process of individual value inquiry, but it isn't helpful for clarifying the value conflicts. Value analysis model focuses on the rational solution of value problem through the logical procedure. But it has the limitations that overemphasizing the logical and systematic aspects results in devaluating students' affective aspects. So it is necessary to coordinate psychological and logical aspects of value inquiry. In this regard, the model was developed, including identifying and clarifying value problem, understanding biological knowledge related to conflict situation, considering on the related persons, searching for alternatives, predicting the consequences of each alternative, selecting the alternative, evaluating the alternative, and final value judgement and affirming it. The educational objectives of value inquiry were selected in consideration of the ability to carry out the steps of the developed model. And the selected contents were animal duplication, test-tube baby, genetic engineering, growth hormone injection problem, brain death, organ transplant, animal to be experimented and were organized on the basis of the 6th and the 7th science curriculum. And the suitable instructional models for the value inquiry education were selected: bioethical value clarification decision-making model, group presentation according to the value analysis model, role play and debate, and discussion through web forum. And the interview was considered to be suitable to evaluate the students' value inquiry ability and the rubric was made to evaluate the attainment of the educational objectives for value inquiry.

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.4
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• pp.243-252
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• 2006

Influence of the increasing carbon dioxide concentration in seawater on various marine organisms is assessed in this article with regard to the impacts of anthropogenic $CO_2$ introduced into surface or deep oceans. Recent proposals to sequester $CO_2$ in deep oceans arouse the concerns of adverse effects of increased $CO_2$ concentration on deep-sea organisms. Atmospheric introduction of $CO_2$ into the ocean can also acidify the surface water, thereby the population of some sensitive organisms including coral reefs, cocolithophorids and sea urchins will be reduced considerably in near future (e.g. in 2100 unless the increasing trend of $CO_2$ emission is actively regulated). We exposed bioluminescent bacteria and benthic amphipods to varying concentrations of $CO_2$ and also pH for a short period. The ${\sim}l.5$ unit decrease of pH adversely affected test organisms. However, amphipods were not influenced by decreasing pH when HCl was used for the seawater acidification. In this article, we reviewed the biological adverse effects of $CO_2$ on various marine organisms studied so for. Theses results will be useful to predict the potential risks of the increase of $CO_2$ concentrations in seawater due to the increase of atmospheric $CO_2$ emission and/or sequestration of $CO_2$ in deep oceans.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.533-538
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• 2013

Potatoes were first introduced outside the Andes region four centuries ago, and have become an integral part of much of the world's food. Potatoes were first introduced into Europe in the 16th century and Korea in the early 19th century. In the nutritional aspects, potatoes contain abundant vitamins and minerals, as well as an assortment of phytochemicals such as carotenoids and natural phenols. Chlorogenic acid constitutes up to 90% of potato natural phenols. Due to the high content of potato functional compounds, it has known that potatoes are effective in the prevention of various human diseases. Recently, color-fleshed potatoes 'Hongyoung' and 'Jayoung' were developed by RDA, and it has reported that they have high content of anthocyanin. Additionally they show higher radical scavenging activity compared to white or yellow fleshed potatoes. So it will be expected that the consumption of color-fleshed potatoes grandually increase by pre-peeled potatoes and color potato chips. This study was conducted to enhance the peel of color-fleshed potatoes utilization and to determine the biological activity of peel of color-fleshed potatoes extract. The anti-inflammatory effects on ethanol extract and its solvent fraction were also evaluated. The anti-inflammatory activities of $CHCl_3$ fraction was evaluated for inhibitory activities against lipopolysacchride(LPS) induced nitric oxide(NO) and prostaglandin $E_2(PGE_2)$ production as well as inducible nitric oxide synthase(iNOS) and cyclo oxygenase-2(COX-2) protein expressions in RAW264.7 cell lines. The fraction inhibitory activity for both tests with $IC_{50}$ values showed in the ranges of $25{\sim}50{\mu}g/ml$. This result revealed that $CHCl_3$ fraction of Jayoung's peel is expected to be good candidate for development into source of anti-inflammatory agent.

• Clean Technology
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• v.24 no.3
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• pp.198-205
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• 2018

This study investigated the influence of catalyst preparation on the activity of $Co-CeO_2$ catalyst for $N_2O$ decomposition. $Co-CeO_2$ catalysts were synthesized by co-precipitation and incipient wetness impregnation. In order to estimate the performance of the as prepared catalysts, direct catalytic $N_2O$ decomposition test was carried out under $250{\sim}375^{\circ}C$. As a result, the catalyst prepared by co-precipitation (CoCe-CP) showed an enhanced performance on $N_2O$ decomposition reaction even in the presence of $O_2$ and/or $H_2O$, whereas the impregnation catalyst (CoCe-IM) did not. In order to investigate the difference in catalytic activity, characterization such as XRD, BET, TEM, $H_2-TPR$, $O_2-TPD$, and XPS was conducted. It is confirmed that the particle size and specific surface area were changed depending on the catalyst preparation method and the synthesis process influenced the physical properties of the catalysts. In addition, the improvement in the activity of the catalyst prepared by co-precipitation is due to the enhanced reduction from $Co^{3+}$ to $Co^{2+}$ and the improved oxygen desorption rate. However, it has been confirmed that the surface electron state and binding energy, which are related to $N_2O$ decomposition, do not change depending on the preparation method.

• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.403-411
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• 2009

This study was conducted to gather the basic data on the increase of utilization for the Japanese staunton vine (Stauntonia hexaphylla), native plants which were grown in the southern districts in Korea. We have also determined their partial physical and chemical compositions and their physiological activities. Vitamin C contents in fruit skin was 85.23 mg/100 g, and that in flesh was 61.67 mg/100 g. Total amino acids contents in fruit skin increased much more by 762.72 mg/100 g DW compared to that in flesh by 434.05 mg/100 g DW. Inorganic matter contents were more increased in the fruit skin (108.48 mg/$\ell$) and its main components were K (76.53 mg/$\ell$), Ca (20.20 mg/$\ell$) and Mg (6.22 mg/$\ell$). Total phenol compound and flavonoid contents in 1,000 mg/$\ell$ methanol extracts were 7.3-9.6 mg/$\ell$ and 5.1-6.7 mg/$\ell$. Nitrite radical scavenging activity in 4,000 mg/$\ell$ methanol extracts of fruit skin and flesh for Stauntonia hexaphylla were 79.5% and 77.8%, however, that in seeds was 17.1%. Overall mushroom tyrosinase inhibition activity (% of control) was less than 10.8%. Anti-microbial activities of methanol extracts from the fruit skin against the gram negative and positive microbial strains were not significant in the lower concentration of extracting solution, however, that from flesh and seeds in terms of the inhibition diameter were $8.91{\sim}12.25\;mm$.

• Clean Technology
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• v.18 no.1
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• pp.102-110
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• 2012

In this study, the production of bio-diesel from animal oil by esterification and trans-esterification was investigated. There were three different extraction methods for oil extraction from raw animal fat. Heterogeneous catalysts such as Amberlyst-15 and Amberlyst BD-20 and a homogeneous catalyst such as sulfuric acid were used for esterification. Among three catalysts, the removal efficiency of Free Fatty Acid (FFA) was the highest in sulfuric acid. Response surface method was carried out to find the optimal esterification condition of sulfuric acid and methanol. After the esterification under the optimal condition, this animal fat was used for the trans-esterification. Animal oil used for trans-esterification was below 1% of FFA content and 0.09% of water content. The catalysts for trans-esterification were KOH, NaOH and $NaOCH_3$. To investigate the effects of catalyst type and amount on trans-esterification, The amount of catalyst were changed with 0.3, 0.6 and 0.9 wt%. The molar ratio of methanol/oil was changed with 4, 6, 9 and 12. The amount of catalyst was fixed to 0.8 wt%. The KOH catalyst showed the highest FAME conversion for trans- esterification, and the optimal methanol/oil weight ratio was 6. In the experiments of various catalysts and methanol molar ratios, the highest content of FAME is 96%. However, this FAME content was below Korean bio-diesel standard which is 96.5% of FAME content. After distillation, FAME content increased to 98%.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.393-397
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• 2004

L-Carnitine $({\beta}-hydroxy-{\gamma}-trimethyl-ammoniumbutyric{\;}acid)$ is a small water-soluble molecule important in mammalian fat metabolism. It is essential for the normal oxidation of fatty acids by the mitochondria, and is involved in the trans-esterification and excretion of acyl-CoA esters. In this paper, to investigate the relationship between aging and L-carnitine, we investigated the effects of in vitro matrix-metalloproteinase (MMP) inhibition and activity and expression of UYA-induced MMPs in human skin fibroblasts. Also, we studied to develop as anti-aging cosmetics with L-carnitine. Fluorometric assays of the proteolytic activities of MMP-1 (collagenase) were performed using fluorescent collagen substrates. ELISA (enzyme linked immune sorbent assay), gelatin-substrate zymography, RT-PCR ELISA techniques were used for the effects of L-carnitine on MMP expression, activity, and MMP mRNA expression in UVA irradiated fibroblast $(5\;J/cm^2)$, respectively. In addition, we performed clinical study with L-carnitine cream. L-carnitine inhibited the activities of MMP-1 in a dose-dependent manner and the $IC_{50}$ values calculated from semi-log plots were 2.45 mM, and L-carnitine showed strong inhibition on MMP-2 (gelatinase) activity in UVA irradiated fibroblast by zymography. Also, UVA induced MMP-1, 2 expression was reduced $43\%,\;53\%$ by treated with L-carnitine at 1.25 mM, and MMP-1 mRNA expression was reduced dose-dependent manner. Therefore L-carnitine was able to significantly inhibit the MMP activity, and regulate MMP expression in protein and mRNA level. The results of clinical study showed that $1.0\%$ L-carnitine treated group reduced wrinkle significantly compared with placebo treated group (P<0.05). All these results suggest that L-carnitine may be useful as new anti-aging cosmetics for protection against UVA induced Mm expression and activity.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• Journal of Life Science
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• v.22 no.12
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• pp.1658-1664
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• 2012

Conjugated linoleic acid (CLA) exhibits several beneficial biological activities including anticarcinogenesis and body-fat reduction. Now, we report that CLA ameliorated the oxidative stress in rat cardiomyoblast cells, H9c2, treated with hydrogen peroxide ($H_2O_2$). Cells were cultured in DMEM/F-12 media at $37^{\circ}C$ with humidified atmosphere of 5% $CO_2$. The cells, cultured for 48 hrs, were seeded at a density $3.5{\times}10^3$ cell/well in a 24 well-plate and incubated for 24 hr. Using these cells, two experiments were performed: the cytotoxicity test of CLA (10, 20, 30, 40, and $50{\mu}Ms$), and the oxidative stress amelioration test of CLA (20 and $50{\mu}Ms$) against cells treated with $H_2O_2$ (10 and 50 ${\mu}Ms$) for 1 and 2 hrs. CLA enhanced the growth of H9c2 cells at any concentrations of CLA and at any incubation times (up to 6 days), indicating that CLA acts as a growth stimulant. No protective effect of CLA (20 and $50{\mu}Ms$) was seen in cells treated $50{\mu}M$ $H_2O_2$ for 1 and 2 hr, but these CLA concentrations ameliorated (p<0.05) the adverse effect of $10{\mu}M$ $H_2O_2$ in cells treated for 1 hr. These CLA concentrations significantly (p<0.05) reduced the proportion of apoptotic cells, relative to control cells. These results suggest that CLA protected H9c2 cells from the oxidative stress of $H_2O_2$ through the suppression of cell apoptosis and could be a useful compound for the prevention of cardiac diseases caused by oxidative stress.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.2
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• pp.153-165
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• 2014

Carbon dioxide capture and storage (CCS) technology is recognizing one of method responding the climate change with reduction of carbon dioxide in atmosphere. In Korea, due to its geological characteristics, sub-seabed geological $CO_2$ storage is regarded as more practical approach than on-land storage under the goal of its deployment. However, concerns on potential $CO_2$ leakage and relevant acidification issue in the marine environment can be an important subject in recently increasing sub-seabed geological $CO_2$ storage sites. In the present study effect data from literatures were collected in order to conduct an effect assessment of elevated $CO_2$ levels in marine environments using a species sensitivity distribution (SSD) various marine organisms such as microbe, crustacean, echinoderm, mollusc and fish. Results from literatures using domestic species were compared to those from foreign literatures to evaluate the reliability of the effect levels of each biological group and end-point. Ecological effect guidelines through estimating level of pH variation (${\delta}pH$) to adversely affect 5 and 50% of tested organisms, HC5 and HC50, were determined using SSD of marine organisms exposed to the $CO_2$-induced acidification. Estimated HC5 as ${\delta}pH$ of 0.137 can be used as only interim quality guideline possibly with adequate assessment factor. In the future, the current interim guideline as HC5 of ${\delta}pH$ in this study will look forward to compensate with supplement of ecotoxicological data reflecting various trophic levels and indigenous species.