• Food Science and Preservation
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• v.31 no.2
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• pp.298-306
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• 2024

This study evaluated the differentiation and protective effects of mixed plant-extract powder in C2C12 muscle cells. Cells were differentiated into myotubes in 2% horse serum (HS)-containing medium with mixed plant-extract powder (MPEP) for 6 days. Treatment with MPEP increased the expression of myogenin and myosin heavy chain (MHC) protein in cells compared with non-treated cells. Differentiated cells were pretreated with MPEP, and hydrogen peroxide (H₂O₂). Our results revealed that treatment with MPEP before H₂O₂ treatment increased cell viability and decreased H₂O₂-induced lactate dehydrogenase (LDH) and creatine kinase (CK). In addition, MPEP attenuated H₂O₂-induced upregulation of Bax, downregulation of Bcl-2, and activation of caspase-9 and -3. These results suggest the MPEP can stimulate C2C12 muscle cell differentiation into myotubes and observe the protective effect of mixed plant-extract powder against muscle oxidative stress. In conclusion, MPEP may be useful as a prevention and treatment material for skeletal muscle disease caused by age-related diseases.

• The Korean Journal of Malacology
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• v.19 no.1
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• pp.9-17
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• 2003

The gonad index (GI), reproductive cycle with gonad developmental phases, first sexual maturity and the sex ratio of the jedo venus, Protothaca jedensis, on the coastal waters of Boryeong, Korea were investigated by histological study. Samples were collected from the subtidal zone of Boryeong, Korea from January to December, 1999. Monthly changes in the gonad index in femal and male clams gradually increased from February and reached the maximum in May, and then the values rapidly decreased from June and reached the minimum in November as seen in variations of the reproductive cycle. The spawning period of this species was once a year between May and July, there was a spawning peak between June and July when seawater temperature was over 20$^{\circ}C$. The reproductive cycle of this species in female and male clams can be classified into five successive stages: early active stage (December to March), late active stage (February to June), ripe stage (April to July), partially spawned stage (May to July) and spent/inactive stage (July to January). Percentages of first sexual maturity of female and male clams of 30.1-35.0 mm in shell length were 52.6% and 60.0%, respectively, and 100% for the clams over 45.1 mm in shell length. The sex ratio of individuals > 30.1 mm in shell length was 1:1 (X$^2$ = 0.40, p > 0.05).

• Proceedings of the Materials Research Society of Korea Conference
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• 1994.11a
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• pp.98-98
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• 1994

최근 청색반도체레이저의 실현을 위하여 ZnSe가 대표하는 II-Ⅵ족 화합물반도체와 Gan가 대표하는 III족 질화물반도체분야에서 집중적인 연구가 이루어지고 있으며, 아직까지 실용화 되지 않고 있는 청색반도체레이저의 출현에 대하여 많은관심이 모아지고 있다. III족 질화물반도체는 InM(Eg:1.9eV)부터 AIN(Eg: 6.2eV)에 이르기까지 전 조성영역에서 완전한 고용체를 이루며, 실온에서 직접천이형 에너지 대구조를 가지므로 청색 혹은 자외영역에서 동작하는 발광소자를 제작하는데 있어 유망시 되고 있는 소재이다. 특히 GaN와 InN의 3원흔정인 GaInN를 활성층으로 이용하면 그 발전파장을 370nm부터 650nm까지 즉 가시 전 영역으로부터 근 자외영역을 포함할 수 있게 된다. 이 연구에서는 AIGaN/GaInN 이중이종접합(DH) 구조의 고아여기에 의한 유도방출고아의 편광 특성을 조사하였다. 유기금속기상에피텍셜(MOVPE)법으로 성장한 AIGaN/GaInN DH 구조의 표면에 수직으로 펄스 발진 질소레이저(파장: 337.1cm, 주기 10Hz, 폭: 8nsec) 빔을 조사하고 DH구조의 단면으로부터의 유도방출광을 편광기를 통과 시킨 후 스펙트럼을 측정하였다. 입사고아 밀도가 증가함에 따라 약 402nm의 파장에서 유도발출에 의한 가도가 큰 피크가 나타났고, 그 반치폭은 약 18meV이었다. 실온에서 AIGaN/GaInN DH 구조로 부터의 유도방출에 필요한 입사광밀도의 임계치는 약 130㎾/$\textrm{cm}^2$이었다. 한편 편광각이 90$^{\circ}$일때는 발광스펙트럼의 강도가 매우 낮고 단지 자연방출에 의한 스펙트럼만이 나타났다. 편광각이 0$^{\circ}$일 때 최대의 방출광 강도를 나타내었으며, 편광각이 -90$^{\circ}$로 회전함에 따라 발고아강도의 강도가 감소하였다. 이와 같은 결과는 광여기에 의하여 AIGaN/GaInN DH 로 부터의 유도방출광이 GaInN활성층의 단면에 평행한 전기장의방향으로, 즉 TE모드로 선형적으로 편광됨을 의미한다. AIGaN/GanN DH 로 부터의 유도방출이 선형적으로 TE모드로 편광되는 것은 이 구조를 이용한 청색 및 자외선 반도체 레이저다이오드의 실현에 매우 유익한 것이다.

• Korean Journal of Medicinal Crop Science
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• v.17 no.4
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• pp.233-237
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• 2009

Astragalus membranaceus has a long history of medicinal use in Chinese herbal medicine. It has been shown to have immunostimulant, tonic, antioxidant, antiperspirant, diuretic, anti-diabetic, expectorant properties, and a supplementary medicine during cancer therapy. In this study, we investigated the effect of anti-oxidation of Astragalus membranaceus root extract. The anti-oxidative activities of water, 80% methanol, and 100% methanol extracts from Astragalus membranaceus were analyzed by DPPH free radical scavenging activity, Superoxide dismutase-like activity, reducing power, and crude ash. The water extract demonstrated to be more effective than methanol extract for a DPPH radicals scavenging activities and reducing power. Superoxide dismutase-like activity showed higher efficiency in 80% methanol extract. Our results indicate that Astragalus membranaceus extracts could be used as a source of antioxidant ingredients in the food industry.

• KSBB Journal
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• v.19 no.2
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• pp.148-153
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• 2004

Lipase catalyzes the hydrolysis of glycerides into fatty acids and glycerol. The study of microbial lipases has been stimulated in resent years. It is due to the potential uses of lipases in esterification of oils to glycerol, alcohols and carbohydrates. Development of lipase producing yeast has been focused concerning to the utilization of yeast culture for animal feed. In this study, yeast like cells was isolated from a waste oil and sludge. A strain having higher lipase activity was selected by random mutagenesis using UV-radiation. The optimal cultivation conditions in submerged culture were examined in terms of lipase production. 2.0％ of high fructose syrup, 1,0％ of CSL, and 1.0％ of olive oil were selected as the nutritional media for the production of lipase. The maximum lipase activity of 1.12 U/ml and viable cell number of 8.8${\times}$10$\^$7/ cells/mL were obtained at 27$^{\circ}C$ with an initial pH of 5.0.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.61-61
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• 2022

섬괴불나무(Lonicera insularis Nakai)는 인동과(Caprifoliaceae) 인동속(Lonicera) 식물로 우리나라 울릉도에 제한적으로 분포한다. 인동과 식물 중 인동(L. japonica Thunb.), 괴불나무[L. maackii (Rupr.) Maxim] 등 다수의 분류군이 약리효능이 입증되었으며, 맛이 뛰어나 차, 술, 음료 등으로 다양하게 활용되고 있다. 그 중 섬괴불나무는 최근 면역자극 및 항비만 활성 등 다양한 약효가 확인되어 약용자원으로서의 잠재적 가치가 큰 것으로 보고된 바 있다. 따라서 본 연구를 통해 특산식물인 섬괴불나무의 적정 자생지를 명확하게 구명하여 보전생물학적 연구, 재배 및 산업화와 같은 현지 외 보전연구를 위한 기초자료로 활용하고자 한다. 연구 결과, 울릉도에서 확인된 섬괴불나무의 주요 분포지는 4개소로 해안도로 일대에 자생하고 있었다. 입지환경은 해발고도 8-20 m, 사면 방위는 남사면, 경사는 15-30°로 완경사지에서 주로 자생하고 있었다. 방형구(10×10 m) 내 개체수는 5-25 개체로 대부분 군락을 이루고 있는 것으로 확인되었다. 4개 조사구에 대한 군집분석을 실시한 결과, 조사구는 곰솔 군집(Pinus thunbergii Parl.)으로 상층의 발달이 거의 없는 전형적인 해안 식생의 구조로 확인되었다. 관목층은 보리장나무(Elaeagnus glabra Thunb.), 송악[Hedera rhombea (Miq.) Bean], 머루(Vitis coignetiae Pulliat ex Planch.) 등이 경쟁관계에 있었으며, 초본층은 왕호장근[Reynoutria sachalinensis (F.Schmidt) Nakai], 갯메꽃[Calystegia soldanella (L.) R.Br], 해국(Aster spathulifolius Maxim.) 등으로 인하여 섬괴불나무는 피압된 것으로 판단된다. 군집의 안전성, 다양성을 나타내는 척도인 종다양성지수는 1.259, 최대종다양성지수는 1.286, 균재도는 0.979, 우점도는 0.021로 확인되었다.

• Journal of Life Science
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• v.29 no.11
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• pp.1173-1178
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• 2019

The purpose of this study was to isolate an agar-degrading marine bacterium and characterize its agarase. Bacterium BK-1, from Gwanganri Beach at Busan, Korea, was isolated on Marine 2216 agar medium and identified as Agarivorans sp. BK-1 by 16S rRNA gene sequencing. The extracellular agarase, characterized after dialysis of culture broth, showed maximum activity at pH 6.0 and $50^{\circ}C$ in 20 mM Tris-HCl buffer. Relative activities at 20, 30, 40, 50, 60, and $70^{\circ}C$ were 67, 93, 97, 100, 58, and 52%, respectively. Relative activities at pH 5, 6, 7, and 8 were 59, 100, 95, and 91%, respectively. More than 90% of the activity remained after a 2 hr exposure to 20, 30, or $40^{\circ}C$; about 60% of the activity remained after a 2 hr exposure to $50^{\circ}C$. Almost all activity was lost after exposure to 60 or $70^{\circ}C$ for 30 min. Zymography revealed three agarases with molecular weights of 110, 90, and 55 kDa. Agarose was degraded to neoagarobiose (46.8%), neoagarotetraose (39.7%), and neoagarohexaose (13.5%), confirming the agarase of Agarivorans sp. BK-1 as a ${\beta}$-agarase. The neoagarooligosaccharides generated by this agarase could be used for moisturizing, bacterial growth inhibition, skin whitening, food treatments, cosmetics, and delaying starch degradation.

• Journal of Life Science
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• v.33 no.4
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• pp.357-362
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• 2023

This report looks at an agar-degrading marine bacterium and characterization of its agarase. Agar-degrading marine bacterium JS-1 was isolated with Marine agar 2216 media from seawater from the seashore of Sojuk-do, Changwon in Gyeongnam Province, Korea. The agar-degrading bacterium was named as Agarivorans sp. JS-1 by phylogenetic analysis based on 16S rRNA gene sequencing. The extracellular agarase was prepared from the culture media of Agarivorans sp. JS-1 and used for characterization. Relative activities at 20℃, 30℃, 35℃, 40℃, 45℃, 50℃, 55℃, and 60℃ were 70%, 74%, 78%, 83%, 87%, 100%, 74%, and 66%, respectively. Relative activities at pH 5, 6, 7, and 8 were 91%, 100%, 90%, and 89%, respectively. Its extracellular agarase showed maximum activity (207 units/l) at pH 6.0 and 50℃ in 20 mM Tris-HCl buffer. The residual activity after heat treatment at 20℃, 30℃, and 50℃ for 30 minutes was 90%, 70%, and 50% or more, respectively. After a 2-hour heat treatment at 20℃, 30℃, 35℃, 40℃, and 45℃, the residual activity was 80%, 68%, 65%, 63%, and 57%, respectively. At 50℃ and above, after heat treatment for 30 minutes, the residual activity was below 60%. Thin layer chromatography analysis suggested that Agarivorans sp. JS-1 produces extracellular β-agarases as they hydrolyze agarose to produce neoagarooligosaccharides such as neoagarohexaose (20.6%), neoagarotetraose (58.5%), and neoagarobiose (20.9%). Agarivorans sp. JS-1 and its thermotolerant β-agarase would be useful in the production of neoagarooligosaccharides, showing functional activity such as inhibition of bacterial growth and delay of starch degradation.

• Journal of Nutrition and Health
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• v.14 no.2
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• pp.97-104
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• 1981

In order to study the changes of components and enzyme activities during Chungkookjang-Koji preparation, the Kojies were prepared with Bacillus Natto, Bacillus subtilis and traditional method. The temperature of Koji materials during Koji preparation was very different according to the experimental group. The content of ethyl alcohol, reducing sugar, amino nitrogen and water soluble nitrogen were changed by the Koji preparing stage and experimental group. Amylase and protease activities showed on irregular change on standing and their activities were not remarkably different among the groups and appeared weakly.

• Journal of Oral Medicine and Pain
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• v.31 no.3
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• pp.265-274
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• 2006

Temporomandibular joint (TMJ) internal derangement, especially disc displacement with reduction (DDwR) is the most common TMJ arthropathy and has been thought to do some effects on masticatory performance. Measuring of maximal bite force has been widely used as objective and quantitative method of evaluating masticatory performance, but previous studies showed various results due to various characteristics of subjects and different measuring devices and techniques. In a few studies about the correlation of bite force and temporomandibular disorders (TMD), some authors reported that bite force and masticatory performance would be reduced in patients with TMD because of pain. But the correlation of changes in structure of articular disc and masticatory performance has not been well investigated yet. In this study, to investigate the influences of non-painful disc change on the masticatory performance, we measured the value of maximal bite force, occlusal contact area and occlusal pressure of 39 patients with non-painful DDwR of the TMJ using pressure sensitive film, and compared it with that of 59 controls. The results are summarized as follows: 1. The maximal bite force (P<0.01) and the occlusal contact area (P < 0.05) of the DDwR patients were greater than the controls. 2. There was no significant difference in occlusal pressure between the DDwR patients and the controls (P > 0.05). 3. The maximal bite force of the male group was greater than that of the female group (P < 0.05). However, the occlusal contact area and the occlusal pressure between the male and the female group didn't show significant difference (P > 0.05). From the results above, we can suggest that DDwR could be a factor of changing bite force, but more controlled, large scaled and EMG related further study is needed.