• Fisheries and Aquatic Sciences
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• 제6권2호
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• pp.59-65
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• 2003

The critical thermal maximum (CTM) of black rockfish, Sebastes schlegeli, was evaluated. Black rockfish were acclimated at $24^{\circ}C$, and then exposed to temperatures from 24 to $33^{\circ}C$. Black rockfish were kept in constant darkness and subjected to a gradual temperature increase $(1 ^{\circ}C\;12^{-1})$. The oxygen consumption rate (OCR) was measured using an automatic intermittent­flow-respirometer (AIFR) during the exposure period (from 119.3 to 143.5 h). The OCR increased from 94.5 to 214.2mL $O_2 kg^{-1}\;ww\;h^{-1}$ as the temperature rose from 24 to $29.4-30.9^{\circ}C$. Subsequently, the OCR increased abruptly, reaching 245.8-412.7mL $O_2 kg^{-1}\;ww\;h^{-1}$ at $32^{\circ}C$. This study suggests that the CTM for black rockfish is $29.4-30.9^{\circ}C$ when temperature is increased at $1^{\circ}C\;12h^{-1}$ following acclimation at $24^{\circ}C$.

• Journal of Plant Biotechnology
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• 제50권
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• pp.169-175
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• 2023

국화 '오블랑'의 기내 배양 잎 절편체로부터 신초 기관형성을 통한 식물체 재생 시스템을 확립하는데 있어 효율적인 신초 재생 및 갈변억제를 위한 식물생장조절제와 AgNO₃의 농도를 선정하고자 실험을 수행하였다. 잎 절편체를 식물생장조절제인 BA 0.5, 1.0, 2.0 mg/L와 NAA 0.2, 0.5, 1.0, 2.0 mg/L를 조합 처리한 12가지 조성의 배지에 치상하여 암조건에서 6주간, 명조건에서 6주간 배양하였을 때, BA 1.0 mg/L, NAA 1.0 mg/L를 첨가한 배지를 사용하는 것이 가장 효과적이었다. 이 결과를 기반으로 잎 절편체로부터 갈변 감소를 위해 MS 염류와 비타민, BA 1.0 mg/L, NAA 1.0 mg/L, sucrose 30 g/L, agar 6 g/L를 포함한 신초유도배지에 AgNO₃ 0, 1, 3, 5, 7, 10 mg/L를 각각 첨가하여 실험을 실시하였다. AgNO₃ 처리는 잎 절편체로부터의 갈변을 감소시키는 효과를 보였으나, 처리 농도가 증가됨에 따라 신초로의 발달은 원활하게 이루어지지 않았다. 결과적으로 AgNO₃ 1 mg/L를 포함한 신초유도배지(MS 염류와 비타민, BA 1.0 mg/L, NAA 1.0 mg/L)에 잎 절편체를 치상하였을 때, 갈변지수 0.7, 절편체당 신초 수가 2.6개로 '오블랑' 재생에 있어 가장 적합한 농도임을 확인하였다.

• 한국식품저장유통학회지
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• 제21권1호
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• pp.40-45
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• 2014

쌀쿠키의 품질 향상을 위하여, 밀가루나 글루텐 무첨가 쌀쿠키의 품질특성에 볶음 커피분말의 첨가가 미치는 영향을 구명하였다. 쌀쿠키는 쌀가루 대비 커피분말을 0, 1.5, 3, 6, 12% 각각 첨가하여 반죽을 한 다음 원판으로 성형한 후 오븐으로 $170{\sim}180^{\circ}C$에서 10분간 구워 만들고 품질특성을 분석하였다. 커피분말 첨가량의 증가와 함께 쌀쿠키의 색도인 $L^*$, $b^*$, $C^*$, $h^{\circ}$값은 감소되었고, $a^*$값은 증가됨을 보였다. 기계적 경도와 총페놀 함량은 커피분말 첨가량에 따라 증가하는 경향을 보였으나 첨가량 1.5%와 3% 간에는 유의적인 차이를 보이지 않았다. 항산화능은 커피분말의 첨가량이 증가할수록 높아지는 경향을 나타내어서 첨가량 1.5% 첨가구보다 3% 첨가구에서 유의적으로 높은 수준을 나타내었다. 관능평가 결과로서, 쌀쿠키의 darkness, smell, bitterness, hardness 등은 커피분말의 첨가량이 증가함에 따라 강하게 평가되는 경향을 보였다. Overall acceptability는 커피분말 1.5%와 3% 첨가구가 유의적으로 가장 좋게 평가되었다. 이로써 쌀쿠키의 항산화능과 기호도의 동시 증대를 위한 커피분말의 첨가량은 3% 정도인 것으로 판단되었다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.109-109
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• 2018

Bacillus subtilis B22, a chemotrophic and aerobic bacterial strain was isolated from homemade kimchi, identified by 16S rRNA gene sequencing. B22 was primarily screened by biochemical, carbon source utilization tests. B22 was used to produce pectinase and ${\beta}$-glucosidase by submerged fermentation under different light sources. B22 was incubated in pectin media and basal media (pH 7.0) under blue, green, red and white light-emitting diodes (LEDs), fluorescent white light, and in darkness at $37^{\circ}C$, orbital shaker 150 rpm for 24 hours. Fermentation under blue LEDs maximized pectinase production ($71.59{\pm}1.6U/mL$ at 24 h) and ${\beta}$-glucosidase production ($56.31{\pm}1.6U/mL$ at 24 h). Further, the production of enzyme increased to pectinase ($156{\pm}1.28U/mL$) and ${\beta}$-glucosidase ($172{\pm}1.28U/mL$) with 3% glucose as a carbon source. Activity and stability of the partially purified enzymes were higher at pH 6.0 to 8.0 and $25-55^{\circ}C$. The effect on the metal ions $Na^+$ and $K^+$ and (moderateactivity) $Mn^{2+}$ and $Ni^{2+}$ increased activity, while $Hg^{2+}$, $Cu^{2+}$, $Fe^{2+}$, and $Fe^{2+}$ inhibited activity. EDTA, phenylmethylsulfonyl fluoride and 5,5-dithiobis (2-nitrobenzoicacid) reduced activity, while tetrafluoroethylene and 1,10-phenanthroline inhibited activity. The amylase was highly tolerant of the surfactants TritonX-100, Tween-20, Tween-80 and compatible with organic solvents methanol, ethanol, isoamylalcohol, isopropanol, t-butylalcohol and the oxidizing agents hydrogen peroxide, sodium perborate and sodium hypochlorite, although potassium iodide and ammonium persulfate reduced activity. These properties suggest utility of pectinase and ${\beta}$-glucosidase produced by B. subtilis B22 under blue LED-mediated fermentation for industrial applications.

• 한국수산과학회지
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• 제46권6호
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• pp.827-834
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• 2013

The effects of environmental factors, such as irradiance, daylength, salinity, and desiccation, on the growth of Lithophyllum yessoense and Hildenbrandia rubra sporelings were examined. Sporelings of each species were cultured with 10, 50, 80, 120, $150{\mu}mol$ photon $m^{-2}s^{-1}$ for 14 days and their maximum growth occurred under $80{\mu}mol$ photon $m^{-2}s^{-1}$. Germlings of both species survived for 21 days in darkness, and even the L.yessoense germlings grew. In the salinity experiment, sporelings of each species survived for 7 days and died after 14 days under 20 and 25 psu, but the sporelings grew well under 34 psu. Physiological features of each species with respect to the evaluated daylengths (8, 12, 14 and 16 h) were slightly different, and maximal growth occurred at 16 h for L. yessoense and at 14 h for H. rubra sporelings. Mortality of the sporelings increased with the exposure period, but H. rubra was less tolerant to desiccation than L. yessoense. In conclusion, sporelings of the two species showed similar growth responses to various environmental factors with slightly different physiological features with respect to salinity, daylength, and desiccation. However, more ecological and physiological studies on slow-growing crustose algae are required to elucidate the expansion of barren ground around the coastal areas of Korea.

• Fisheries and Aquatic Sciences
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• 제5권3호
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• pp.191-199
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• 2002

Pacific oysters Crassostrea gigas (Thunberg) were collected on April, 1999 and March­September, 2000 from Goseung Bay along the southern coast of Korea. The oysters tested cp;;ected from a depth of 0.5-2 m in which they cultured by a long line hanging method. The oxygen consumption rates (OCR) of oysters held under constant temperature and darkness (CC), were determined using an automatic intermittent-flow-respirometer (AIFR). Depending on holding periods after oyster collection, the experiments were divided into two groups: Group 7-d (held to ambient temperature for ca. 7 days) and Group 2l-d (held to ambient temperature for ca. 21 days). The OCR for Group 7-d single oyster displayed two peaks every day under CC, while Group 2l-d single oyster showed one peak every day. It is likely that the rhythmic patterns 02.6-12.8 hours) of the OCR in the Group 7-d single oyster may have been influenced by tidal currents at the sampling site. The rhythmic patterns (24.3-24.7 hours) in the Group 2l-d single oyster may have been shifted from two peaks to one peak each day under CC. The present study concludes that the OCR rhythm of wild oysters in nature is governed by two lunar-day clocks (24.8 hours); one driving one peak and the other driving the second peak. When oysters are subjected to the long-term CC conditions, one of the two-clock systems is depressed or only intermittently becomes active. Jpwever. the OCR rhythms by two to three oysters occurred arrhythmic patterns during the experiments and exhibited some evidence of weak rhythmicity of compared to those of a single oyster. It could be partly due to differences group effects.

• The Journal of Advanced Prosthodontics
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• 제5권2호
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• pp.75-83
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• 2013

PURPOSE. Maxillofacial silicone elastomer is usually colored intrinsically with color pigments to match skin colors. The purpose of this study was to investigate the color stability of a maxillofacial silicone elastomer, colored with a thermochromic, color changing pigment. MATERIALS AND METHODS. Disc-shaped maxillofacial silicone specimens were prepared and divided into 3 groups: a conventionally colored control group, one group additionally colored with 0.2 wt% thermochromic pigment, and one group with 0.6 wt% thermochromic pigment. Half of the surface of each specimen was covered with an aluminium foil. All of the specimens were exposed to UV radiation in 6 hour cycles over 46 days. In between the UV exposures, half of the specimens were stored in darkness, at room temperature, and the other half was stored in an incubator, at a humidity of 97% and a temperature of $+37^{\circ}C$. Color measurements were made with a spectrophotometer and registered according to the CIELAB $L^*a^*b^*$ color model system. The changes in $L^*$, $a^*$ and $b^*$ values during artificial aging were statistically analyzed by using paired samples t-test and repeated measures ANOVA. P-values <.05 were considered as statistically significant. RESULTS. The UV exposure resulted in visually noticeable and statistically significant color changes in the $L^*$, $a^*$ and $b^*$ values in both of the test groups containing thermochromic pigment. Storage in the incubator lead to statistically significant color changes in the $a^*$ and $b^*$ values of the specimens containing thermochromic pigment, compared to those stored at room temperature. CONCLUSION. The specimens containing thermochromic pigment were very sensitive to UV radiation, and the thermochromic pigment is not suitable, as such, to be used in maxillofacial prostheses.

• Fisheries and Aquatic Sciences
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• 제4권3호
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• pp.130-137
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• 2001

In the present study, the locomotor and feeding activities of single red sea bream, Pagrus major were simultaneously investigated to examine the existence of such dual behaviour. Seven red sea bream of 13cm body length on average were placed individually in 35L tanks equipped with an infrared sensor and a newly developed demand-feeding device. Fish were exposed to a light: dark 12: 12h cycle and constant darkness (DD) to study endogenous rhythmicity. Under LD 12: 12 h, the daily pattern of behaviour differed between individual fish; some red sea bream were diurnal and others were nocturnal. Futhermore, some of them displayed an extraordinary flexibility in phasing because they were dark active but light feeding, and vice versa. Under DD, red sea bream showed free-running rhythms for locomotor activity and feeding. These results indicate that the type of phasing of locomotor activity did not necessarily decide the feeding phase; much of this is explained by the fact that red sea bream were demand-fed. Flexibility in phasing and a certain degree of independence between locomotor and feeding activities could be seen as an adaptative response of the highly adaptable circadian rhythms of fish.

• 수산해양교육연구
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• 제28권4호
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• pp.1098-1106
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• 2016

To study the influence of light intensity on blind-side hypermelanosis of starry flounder, Platichthys stellatus, we compared growth, glucose, cortisol, ratio of malpigmented blind-side area, ambicolored fish ratio and expression of mch mRNA for 60 days in 0 lux(darkness) and 20 lux(low light density). The test was done in duplicate at 50 fish/tank with the selected ordinary juvenile flounder. The rearing was performed in FRP aquarium tanks ($H100cm{\times}L100cm{\times}W100cm$). Growth was higher in the 0 lux. The ratio of malpigmented blind-side area and ambicolored fish ratio were significantly higher at the 0 lux than at the 20 lux. The result suggests that 20 lux could inhibit the hypermelanosis. The expression level of MCH 1, 2 mRNA was significantly lower in 0 lux, indicating that MCH 1, 2 and light intensity are related to blind-side hypermelanosis of starry flounder.

• 한국식생활문화학회지
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• 제37권6호
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• pp.529-539
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• 2022

This study investigated the quality characteristics of madeleines prepared using varying amounts of roasted black soybean flour (RBF). The RBF was used to substitute 0% (control group), 20% (RBF-20 group), 40% (RBF-40 group) and 60% (RBF-60 group) of weak flour (WF) in the manufacture of madeleine. The substitution of WF with RBF showed decreased the pH but increased the sugar concentration of the batter (p<0.01). Low lightness (L) and low yellowness (b) were observed in the experimental groups at high ratios of RBF substitution (p<0.05). The experimental groups of madeleines showed higher hardness and chewiness than the control group (p<0.001). The principal component analysis of the RBF-60 experimental group, which had the highest proportion of RBF, showed that it had relatively strong characteristics with respect to "darkness", "soybean odor", "sesame odor", "grains odor", "savory flavor", "sweetness", "black soybean taste", and "moistness". The acceptance test results, showed that the RBF-20 experimental group was similar to the control group with respect to "odor acceptance", "taste acceptance", and "texture acceptance". Thus, this study confirmed the possibility of using RBF for the preparation of madeleines.