• 한국수산과학회지
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• 제53권1호
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• pp.123-131
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• 2020

In this study, we investigated the protective effects of a Neutrase enzymatic hydrolysate derived from Korea pen shell Atrina pectinata (APN) against hydrogen peroxide (H₂O₂)-induced oxidative damage in hepatocytes. First, we confirmed that APN has antioxidant activities by scavenging 2,2-azino-bis (3-ethylbenzthiazoline)-6-sulfonic acid radical (ABTS⁺) and H₂O₂ and increasing oxygen radical absorbance capacity (ORAC) value. Also, the treatment of APN increased the cell viability by reducing the intracellular reactive oxygen species (ROS) production in H₂O₂-stimulated hepatocytes. In addition, APN decreased the sub-G₁ DNA contents and the apoptotic body formation increased by H₂O₂ stimulation. Moreover, APN modulated the protein expression of apoptosis related molecules (Bcl-2, Bax and p53) by suppressing the activation of nuclear factor NFkB and ERK/p38 signaling in H₂O₂-stimulated hepatocytes. Furthermore, APN led to the activation of Nrf2/HO-1signaling known as antioxidant systems. These results suggest APN protects hepatocytes against oxidative damages caused by H₂O₂ stimulation.

• Asian-Australasian Journal of Animal Sciences
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• 제32권3호
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• pp.350-356
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• 2019

Objective: To examine the regulatory effects of exercise on myokine expression in horse skeletal muscle cells, we compared the expression of several myokine genes (interleukin 6 [IL-6], IL-8, chemokine [C-X-C motif] ligand 2 [CXCL2], and chemokine [C-C motif] ligand 4 [CCL4]) after a single bout of exercise in horses. Furthermore, to establish in vitro systems for the validation of exercise effects, we cultured horse skeletal muscle cells and confirmed the expression of these genes after treatment with hydrogen peroxide. Methods: The mRNA expression of IL-6, IL-8, CXCL2, and CCL4 after exercise in skeletal muscle tissue was confirmed using quantitative-reverse transcriptase polymerase chain reactions (qRT-PCR). We then extracted horse muscle cells from the skeletal muscle tissue of a neonatal Thoroughbred. Myokine expression after hydrogen peroxide treatments was confirmed using qRT-PCR in horse skeletal muscle cells. Results: IL-6, IL-8, CXCL2, and CCL4 expression in Thoroughbred and Jeju horse skeletal muscles significantly increased after exercise. We stably maintained horse skeletal muscle cells in culture and confirmed the expression of the myogenic marker, myoblast determination protein (MyoD). Moreover, myokine expression was validated using hydrogen peroxide ($H_2O_2$)-treated horse skeletal muscle cells. The patterns of myokine expression in muscle cells were found to be similar to those observed in skeletal muscle tissue. Conclusion: We confirmed that several myokines involved in inflammation were induced by exercise in horse skeletal muscle tissue. In addition, we successfully cultured horse skeletal muscle cells and established an in vitro system to validate associated gene expression and function. This study will provide a valuable system for studying the function of exercise-related genes in the future.

• 생명과학회지
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• 제27권7호
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• pp.783-789
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• 2017

Malus melliana (Hand.-Mazz.) Rehder (M. melliana)는 장미과에 속하는 중국 자생 식물 중 하나로 현재까지 보고된 생리활성은 전무하다. 본 연구에서는 M. melliana 에탄올 추출물(MMEE)의 항산화 및 항염증 생리활성을 DPPH 라디칼 소거능, ROS 소거능, NO 생성 저해능 및 Western blot hybridization을 통한 연관 단백질 발현분석을 통해 평가하였다. MMEE의 항산화능을 DPPH 라디칼 소거능을 통해 분석한 결과 양성 대조군으로 사용한 대표적인 항산화제인 아스코르빈산과 유사한 정도의 높은 소거활성을 보여 MMEE가 매우 강한 항산화능을 보유함을 확인하였다. 또한 RAW 264.7 세포주에서 $H_2O_2$에 의해 유도된 ROS에 대한 MMEE의 소거능을 분석한 결과, 농도의존적인 강한 ROS 소거능을 보였다. 뿐만 아니라 대표적인 항산화 효소인 HO-1 및 그 전사 인자인 Nrf2의 단백질 발현에 미치는 영향을 분석한 결과 MMEE에 의해 HO-1 및 Nrf2의 발현이 증가됨을 보였다. 한편 MMEE가 LPS에 의해 유도된 NO 생성에 미치는 영향을 분석한 결과 농도의존적인 NO 생성 저해능을 보였으며 이는 NO 생성 단백질인 iNOS의 발현 저해에서 기인함을 확인하였다. 이러한 결과를 통해 MMEE의 높은 항산화능과 항염증 활성을 확인하였으며 향후 잠재적인 기능성 소재로서 유용하게 활용될 수 있을 것으로 판단된다. 추후 계속적인 연구를 통해 활성 물질의 규명이 필요할 것으로 판단된다.

• Journal of Microbiology and Biotechnology
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• 제31권3호
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• pp.464-474
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• 2021

Bacterial cytochrome P450 (CYP) enzymes are responsible for the hydroxylation of diverse endogenous substances with a heme molecule used as a cofactor. This study characterized two CYP154C3 proteins from Streptomyces sp. W2061 (CYP154C3-1) and Streptomyces sp. KCCM40643 (CYP154C3-2). The enzymatic activity assays of both CYPs conducted using heterologous redox partners' putidaredoxin and putidaredoxin reductase showed substrate flexibility with different steroids and exhibited interesting product formation patterns. The enzymatic characterization revealed good activity over a pH range of 7.0 to 7.8 and the optimal temperature range for activity was 30 to 37℃. The major product was the C16-hydroxylated product and the kinetic profiles and patterns of the generated hydroxylated products differed between the two enzymes. Both enzymes showed a higher affinity toward progesterone, with CYP154C3-1 demonstrating slightly higher activity than CYP154C3-2 for most of the substrates. Oxidizing agents (diacetoxyiodo) benzene (PIDA) and hydrogen peroxide (H2O2) were also utilized to actively support the redox reactions, with optimum conversion achieved at concentrations of 3 mM and 65 mM, respectively. The oxidizing agents affected the product distribution, influencing the type and selectivity of the CYP-catalyzed reaction. Additionally, CYP154C3s also catalyzed the C-C bond cleavage of steroids. Therefore, CYP154C3s may be a good candidate for the production of modified steroids for various biological uses.

• 유기물자원화
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• 제20권1호
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• pp.78-86
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• 2012

본 연구에서는 제 3세대 바이오매스 미세조류를 이용한 혐기성 암발효 수소 생산 과정에서 산 전처리의 최적화를 통계학적 실험방법인 반응표면법을 적용하여 도출 하였다. 1~3% (v/w)의 산 농도와 10~60 min 전처리 시간을 최적화 실험 범위로 설정하였으며 기질농도 76 g dcw/L와 초기 pH는 7.4로 고정하였고 수소발효 운전 중에 pH는 조절하지 않았다. 최적화 결과 HCl 1.2%와 반응시간 48 min에서 가장 높은 수소전환율인 36.8 mL $H_{2}/g$ dcw을 얻었으며 이때 가용화율은 18.9%로 나타났다. 정확도는 $R^{2}$=0.95로 매우 정확한 상관계수를 보였고 ANOVA test를 통해 예측된 수소전환율에 관련한 경험식은 a quadratic polynomial equation 으로 나타났으며 반응시간보다 산주입농도가 수소 생산에 큰 영향을 미치는 것으로 나타났다.

• Journal of the Korean Wood Science and Technology
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• 제48권6호
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• pp.769-779
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• 2020

This study investigates the selective fractionation of lignin with uniform structures and lower molecular weight. Lignin solubilization was first performed using a solution of acetic acid (AA) and hydrogen peroxide (HP) (4:1, (v/v)) to form peracetic acid (PAA), which is a strong oxidant. After the PAA-induced solubilization that occurred at 80℃, totally soluble lignin was extracted by ethyl acetate (EA) and divided into organic- and water-soluble fractions. The EA fraction was then fractionated by open-column using three solutions (chloroform-ethyl acetate, methanol, and water) sequentially. With an increase in the solvent polarity during the fractionation step, the molecular weight of the lignin-derived compounds in the fraction increased. Remarkably, some lignin fractions did not have aromatic structures. These fractions were identified as carboxylic acid-containing polymers like poly-carboxylates. These results conclude that the selective production of lignin-derived polymers with specific molecular weight and structural characteristics could be possible through open-column fractionation.

• 생명과학회지
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• 제22권11호
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• pp.1507-1514
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• 2012

산수유는 다양한 생리적 기능을 가지는 것으로 보고되어 있으며 또한 최근에 관심의 증가로 산수유로부터 유효성분의 추출 방법 개발은 산업적으로 매우 중요하며, 유효성분의 존재 여부를 분석하는 것은 산업적 상품의 진위와 품질을 판정하는데 중요한 수단이 된다. 본 연구는 loganin을 지표 물질로 하여 산수유로부터 유효성분을 추출하는 여러 방법을 비교 분석하였으며, 각 방법에 따라 추출한 시료의 기능성의 차이를 항산화 작용으로 분석하였다. 산수유로부터 항산화 성분을 추출하기 위하여 네 가지 방법을 적용하였다. 추출된 유효성분 지표물질로 loganin의 함량을 HPLC로 분석하였을 때 열수를 사용한 추출 방법이 알코올 추출 또는 효소 처리 방법 보다 효율적인 결과를 보여 주었다. 각 추출 시료의 항산화 기능은 DPPH radical 소거능, hydrogen peroxide scavenging assay, reducing power 측정으로 분석하였다. 추출 방법에 따라 항산화 기능이 차이가 있었으며, 열수 추출 시료가 DPPH radical 소거능과 hydrogen peroxide scavenging 효과가 우수하였고, 효소 처리 추출 시료는 reducing power가 우수하게 나타났다. 추출 방법에 따라 시료에 함유된 성분의 차이가 항산화 기능이 차이와 연관이 있다고 생각된다. 이 연구에서 얻은 결과는 산수유는 대조군으로 사용한 vitamin C에 준하는 항산화 성분을 함유하고 있으며, 이들 성분은 열수 추출 방법으로 효율적으로 추출되었으며, 열수 추출 방법은 산업적으로 응용될 수 있음을 제시하고 있다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.107-107
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• 2010

Hydrogen is an alternative fuel for the future energy which can reduce pollutants and greenhouse gases. Synthesis gas have played an important role of synthesizing the valuable chemical compound, for example methanol, DME and GTL chemicals. Renewable biomass feedstocks can be potentially used for fuels and chemical production. Current thermal processing techniques such as fast pyrolysis, slow pyrolysis, and gasification tend to generate products with a large slate of compounds. Lignocellulose feedstocks such as forest residues are promising for the production of bio-oil and synthesis gas. Pyrolysis and gasification was investigated using thermogravimetric analyzer (TGA) and bubbling fluidized bed gasification reactor to utilize forest woody biomass. Most of the materials decomposed between $320^{\circ}C$ and $380^{\circ}C$ at heating rates of $5{\sim}20^{\circ}C/min$ in thermogravimetric analysis. Bubbling fluidized bed reactor were use to study gasification characteristics, and the effects of reaction temperature, residence time and feedstocks on gas yields and selectivities were investigated. With increasing temperature from $750^{\circ}C$ to $850^{\circ}C$, the yield of char decreased, whereas the yield of gas increased. The gaseous products consisted of mostly CO, CO2, H2 and a small fraction of C1-C4 hydrocarbons.

• Journal of Microbiology and Biotechnology
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• 제30권10호
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• pp.1500-1509
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• 2020

Drought is a major abiotic factor and has drastically reduced crop yield globally, thus damaging the agricultural industry. Drought stress decreases crop productivity by negatively affecting crop morphological, physiological, and biochemical factors. The use of drought tolerant bacteria improves agricultural productivity by counteracting the negative effects of drought stress on crops. In this study, we isolated bacteria from the rhizosphere of broccoli field located in Daehaw-myeon, Republic of Korea. Sixty bacterial isolates were screened for their growth-promoting capacity, in vitro abscisic acid (ABA), and sugar production activities. Among these, bacterial isolates YNA59 was selected based on their plant growth-promoting bacteria traits, ABA, and sugar production activities. Isolate YNA59 highly tolerated oxidative stress, including hydrogen peroxide (H₂O₂) and produces superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) activities in the culture broth. YNA59 treatment on broccoli significantly enhanced plant growth attributes, chlorophyll content, and moisture content under drought stress conditions. Under drought stress, the endogenous levels of ABA, jasmonic acid (JA), and salicylic acid (SA) increased; however, inoculation of YNA59 markedly reduced ABA (877 ± 22 ng/g) and JA (169.36 ± 20.74 ng/g) content, while it enhanced SA levels (176.55 ± 9.58 ng/g). Antioxidant analysis showed that the bacterial isolate YNA59 inoculated into broccoli plants contained significantly higher levels of SOD, CAT, and APX, with a decrease in GPX levels. The bacterial isolate YNA59 was therefore identified as Variovorax sp. YNA59. Our current findings suggest that newly isolated drought tolerant rhizospheric Variovorax sp. YNA59 is a useful stress-evading rhizobacterium that improved drought-stress tolerance of broccoli and could be used as a bio-fertilizer under drought conditions.

• Mycobiology
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• 제35권3호
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• pp.135-144
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• 2007

The removal efficiency of the heavy metals Zn, Pb and Cd by the zoosporic fungal species Saprolegnia delica and the terrestrial fungus Trichoderma viride, isolated from polluted water drainages in the Delta of Nile in Egypt, as affected by various ranges of pH values and different temperature degrees, was extensively investigated. The maximum removal efficiency of S. delica for Zn(II) and Cd(II) was obtained at pH 8 and for Pb(II) was at pH 6 whilst the removal efficiency of T. viride was found to be optimum at pH 6 for the three applied heavy metals. Regardless the median lethal doses of the three heavy metals, Zn recorded the highest bioaccumulation potency by S. delica at all pH values except at pH 4, followed by Pb whereas Cd showed the lowest removal potency by the fungal species and vice versa in case of T. viride. The optimum bio-mass dry weight production by S. delica was found when the fungus was grown in the medium treated with the heavy metal Pb at pH 6, followed by Zn at pH 8 and Cd at pH 8. The optimum biomass dry weight yield by T. viride amended with Zn, Pb and Cd was obtained at pH 6 for the three heavy metals with the maximum value at Zn. The highest yield of biomass dry weight was found when T. viride treated with Cd at all different pH values followed by Pb whilst Zn output was the lowest and this result was reversed in case of S. delica. The maximum removal efficiency and the biomass dry weight production for the three tested heavy metals was obtained at the incubation temperature $20^{\circ}C$ in case of S. delica while it was $25^{\circ}C$ for T. viride. Incubation of T. viride at higher temperatures ($30^{\circ}C\;and\;35^{\circ}C$) enhanced the removal efficiency of Pb and Cd than low temperatures ($15^{\circ}C\;and\;20^{\circ}C$) and vice versa in case of Zn removal. At all tested incubation temperatures, the maximum yield of biomass dry weight was attained at Zn treatment by the two tested fungal species. The bioaccumulation potency of S. delica for Zn was higher than that for Pb at all temperature degrees of incubation and Cd bioaccumulation was the lowest whereas T. viride showed the highest removal efficiency for Pb followed by Cd and Zn was the minor of the heavy metals.