• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.73-84
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• 2015

In this research, two careers connectable with the contents of the curriculum of fifth to sixth grade elementary school students were selected among other promising future careers in biotechnology and medical engineering fields. 'Design-based promising future career STEAM program' was developed and its validity and effectiveness were verified. Reflecting recent issues, and complying with the STEAM standard (frame) instructional materials were developed through group deliberations for nine months, based on the achievement standards through an analysis of subject curriculum revised in 2009. This was prepared so that students are able to experience biotechnology and medical engineering related careers in a simulational form emphasized with creative design to make them prefer natural sciences and engineering careers and draw their interests and recognition of the relevant careers under the two disciplines. As a result of such application to STEAM Leader School students at the verification stage of the program, the contents and level of the program were verified suitable, receiving favorable reviews. And as a result of applying the developed program on other elementary school students, it was discovered that significant improvements were found in their career consciousness. Through this research, it was suggested that there is a need for a simplification of the curriculum content standards, a provision of 'standard for integration,' development of teachers' ability in reconstituting or organizing the STEAM and proceeding classes, continuous long-term support to see the effects of a policy or a program, and a reinforcement of career education integrated in the curriculum.

• Food Science and Preservation
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• v.15 no.1
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• pp.49-57
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• 2008

This study was conducted to develop an optimal composite recipe for a cookie including yam powder that would be attractive to all age groups. Wheat flour was partially substituted by yam powder to reduce the content of wheat flour. This study has produced the sensory optimal composite recipe by making cookies, respectively with each 5 level of yam powder $(X_1)$, Sugar$(X_2)$, butter$(X_3)$, by C.C.D (Central Composite Design) and conducting sensory evaluation and instrumental analysis by means of RSM (Response Surface Methodology). Sensory items showed very significant values in color, softness, overall quality (p<0.01), flavor (p<0.05) and those of instrumental analysis showed significant values in lightness, redness (p<0.05), spread ratio, hardness (p<0.01). Also sensory optimal ratio of yam cookie was calculated at yam powder 37.35 g, sugar 50.75 g, butter 78.40 g and it was revealed that the factors of influencing yam cookie aptitude were in older of yam powder, butter, sugar.

• Food Science and Preservation
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• v.23 no.7
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• pp.995-1003
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• 2016

Ulmus pumila L. bark underwent distilled water extraction under three temperature condition ($4^{\circ}C$, room temperature, or $80^{\circ}C$) and two extraction times (1, or 5 min) in order to develop a functional beverage products. Changes in yield, pH, color, total phenolic (TP) content, tannin content and antioxidant activity of the aqueous extracts were evaluated for each extraction temperature and duration. Extraction conditions did not affect yield or pH value of the extracts; however CIE $b^*$ values were high in extracts prepared under high extraction temperature ($80^{\circ}C$) and long extraction duration (5 min) conditions. Both extraction temperature and duration affected the TP and tannin contents of the extracts; however, all extraction conditions resulted in ${\geq}450\;mg\;GAE/g$ TP content and ${\geq}80\;mg\;CE/g$ tannin content. All extracts exhibited ABTS and DPPH radical scavenging ability similar to that of vitamin C. Nitric oxide inhibition activity was lower in the 5 min duration sample than in the 1 min sample. The $4^{\circ}C$ extraction temperature produced an extract with the highest reducing power and hydrogen peroxide values. Extraction temperature also affected sensory evaluation results with the $80^{\circ}C$ extraction temperature producing significantly higher flavor, bitterness, and color score, than those obtained under $4^{\circ}C$ and room temperature extraction conditions.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.279-286
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• 2005

Microbial contamination origin of Kimbab was determined using nine types of ready-to-use ingredients, three each from animal, seafood, and vegetable sources. Effect of radiation on microbiological safety was also investigated. Total aerobic bacteria were not detected in seasoned beef, ham, and seasoned burdock, whereas 3.50, 5.41, 8.83, and 5.07 log CFU/g were detected in surimi gel, seasoned and blanched spinach, dried laver, and cucumber, respectively. Total aerobic bacterial and mold numbers were 8.73 and 5.08 log CFU/g in prepared Kimbab. Gamma irradiation reduced level of contaminated aerobic bacteria and mold population in Kimbab and its ingredients, Salmonella mutagenicity assay (Ames test) showed Kimbub ingredients irradiated at 10 kGy did not show any mutagenicity. These results indicate ready-to-use kimbab ingredients were mostly responsible for total aerobic bacteria and mold population of Kimbab, and low dose irradiation and low temperature storage ($10^{\circ}C$) effectively ensured microbiological safety of Kimbab and ready-to-use ingredients.

• Journal of Life Science
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• v.19 no.7
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• pp.994-1002
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• 2009

A bacteriocin-producing bacterium identified as Bacillus licheniformis was isolated from soybean sauce. Antibacterial activity was confirmed by paper disc diffusion method, using Micrococcus luteus as a test organism. The bacteriocin also showed antibacterial activities against Bacillus sphaericus, Lactobacillus bulgaricus, Lactobacillus planiarum, Paenibacillus polymyxa, and Pediococcus dextrinicus. Optimal culture conditions for the production of bacteriocin was attained by growing the cells in an MRS medium at a pH of 6.5~ 7.0 and a temperature of 37$^\circ$C for 36$\sim$48 hr. Solvents such as chloroform, ethanol, acetone, and acetonitrile had little effect on bacteriocin activity. However, about 50% of bacteriocin activity diminished with treatment of methanol and isopropanol at the final concentration of 50% at 25$^\circ$C for 1 hr. It was stable against a pH variation range from 3.0 and 7.0, but the activity reduced to 50% at a pH range from 9.0 to 11.0. It's activity was not affected by heat treatment at 100$^\circ$C for 30 min and 50% of activity was retained after heat treatment at 100$^\circ$C for 60 min, showing high thermostability. The bacteriocin was purified to a homogeneity through ammonium sulfate precipitation, SP-Sepharose ion-exchange chromatography, and reverse-phase high-performance liquid chromatography (HPLC). The entire purification protocol led to a 75-fold increase in specific activity and a 13.5% yield of bacteriocin activity. The molecular weight of purified bacteriocin was estimated to be about 2.5 kDa by tricine-SDS-PAGE.

• Korean Journal of Medicinal Crop Science
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• v.16 no.4
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• pp.255-260
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• 2008

This study was performed to investigate the enhancement of UV-protection activities and skin-whitening effects from Angelica gigas Nakai extracts on ultra high pressure extraction process. Extraction at $60^{\circ}C$ treated by ultra high pressure for 15 minute and associated with ultrasofication (HPE15) was showed more than double yield, compare conventional extraction, as 12.24% (w/w) from A. gigas. Extracts of HPE15 reduced expression of MMP-1 on UV-irradiated CCD-986sk cells as 122.2% and revealed high inhibitory potency on tyrosinase as 69.4% by adding samples. Extracts of HPE15 from A. gigas showed strong inhibition effect on melanin production test by Clone M-3 cells as 82.4% by adding extracts. From the preliminary observations, we considered that the extracts from A. gigas could be potent natural materials for skin-whitening agent, and could be used as a potential anti-aging agent for the photo-damaged skin.

• KSBB Journal
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• v.23 no.6
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• pp.463-469
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• 2008

During the last decade, monacolin-K biosynthesized by fermentation of red yeast rice (Monascus strains) was proved to have an efficient cholesterol lowering capability, leading to rapid increase in the market demand for the functional red yeast rice. In this study, the production medium composition and components were optimized on a shake flask scale for monacolin-K production by Monascus pilosus (KCCM 60160). The effect of three different soybean flours on the monacolin-K production were studied in order to replace the nitrogen sources of basic production medium (yeast extract, malt extract and beef extract). Among the several experiments, the production medium with dietary soybean flour to replace a half of yeast extract was very good for monacolin-K production. Plackett-Burman experimental design was used to determine the key factors which are critical to produce the biological products in the fermentation. According to the result of Plackett-Burman experimental design, a second order response surface design was applied using yeast extract, beef extract and $(NH_4)_2SO_4$ as factors. Applying this model, the optimum concentration of the three variables was obtained. The maximum monacolin-K production (369.6 mg/L) predicted by model agrees well with the experimental value (418 mg/L) obtained from the experimental verification at the optimal medium. The yield of monacolin-K was increased by 67% as compared to that obtained with basic production medium in shake flasks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1533-1543
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• 2016

The anti-stress effects of Punica granatum L. (family Lythraceae, PG) on $H_2O_2$/corticosterone (CORT)-induced stress in cells and sleep-deprived rats were investigated. The PG extract showed neuroprotective effects in SH-SY5Y cells against $H_2O_2$/CORT-induced stress. Sleep deprivation led to behavioral, hormonal, and biochemical alterations in the animal model. The effects of P. granatum on physiological, behavioral, and biochemical parameters aggravated by sleep deprivation were investigated. Sleep deprivation impaired physiological (survival, body weight, and drowsiness scores) and behavioral (rotarod, passive avoidance, hot hyperalgesia, and Y maze) parameters as well as biochemical factors (cortisol, serotonin, dopamine, testosterone, and growth factor I contents in serum). These parameters were significantly recovered by PG extract in a concentration-dependent manner. The PG extract also enhanced catalase, superoxide dismutase, and non-enzymatic antioxidative activities such as glutathione compared to sleep-deprived rats. On the basis of these results, our findings suggest that Punica granatum prevents impairment of body functions induced by sleep deprivation and related oxidative damage.

• Korean Journal of Food Science and Technology
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• v.46 no.4
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• pp.456-464
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• 2014

Kimchi was prepared with three types of salt (4-year-aged solar salt, FS; 1-year-aged solar salt, OS; and purified salt, PS), using Leuconostoc citreum GJ7 as the starter culture. The prepared kimchi was fermented (up to 0.5-0.6% of acidity) and stored for 5 months at $-1^{\circ}C$. During the storage period, the acidity of FS kimchi increased gradually, whereas that of PS kimchi increased sharply. The yellowness (b) color value of PS kimchi (63.4) was higher than that of other kimchis with solar salts (55.6-60.3). Hardness of FS kimchi (1,912.6 gf) was greater than that of the other kimchis (1,554.4-1,650.2 gf) during the storage period. Moreover, sensory evaluation showed higher scores for FS kimchi than for other kimchis. These results suggest that FS is more suitable salt than PS for long-term storage of kimchi.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.4
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• pp.293-303
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• 2017

To elucidate the physiological responses of rice plants to the essential mineral silicon (Si), we assessed the effects of treatments with Si, nitrogen ($NH_4NO_3$; ammonium nitrate), and calcium ($CaCl_2$; calcium chloride), independently or in combination on mineral uptake rates and levels of the hormones abscisic acid (ABA), gibberellin ($GA_1$) and jasmonic acid (JA). We found that nitrogen and calcium uptake was inhibited by Si application. However, solo application of nitrogen or calcium did not affect Si uptake. Compared to the untreated plants, the application of Si, $NH_4NO_3$ or $CaCl_2$ increased the endogenous hormone levels in treated plants. In particular, the concentrations of $GA_1$ and JA increased significantly after the application of Si or $NH_4NO_3$. The level of $GA_1$ observed after a treatment (solo or combine) with Si, and $NH_4NO_3$ was higher than that of the control. By contrast, independent application of $CaCl_2$ or a combined treatment with Si and $CaCl_2$ did not alter $GA_1$ levels. The highest level of $GA_1$ was present in plants given a combination treatment of Si and $NH_4NO_3$. This effect was observed at all time points (6 h, 12 h and 24 h). Endogenous JA contents were higher in all treatments than the control. In particular, a combination treatment with Si and $NH_4NO_3$ significantly increased the JA levels in plants compared to other treatments at all time points. A small increase in JA levels was observed after 6 h in plants given the $CaCl_2$ treatment. However, JA levels did not differ between plants given a $CaCl_2$ treatment and controls after 12 h or 24 h of exposure. We conclude that treatment with $CaCl_2$ alone does not affect endogenous JA levels in the short term. Endogenous ABA contents did not show any differences among the various treatments.