• Journal of the Korean Applied Science and Technology
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• v.38 no.5
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• pp.1302-1313
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• 2021

In this study, Gami-Sumiwon (GS; Cynanchi wilfordii R., Angelica gigantis R., Lycium chinense M., Betula platyphylla S., Cryptotympana atrata F. and Carthamus tinctorius L.) and/or Sinomenium acutum R. (SC) was extracted with 70% ethanol or water. And We investigated the antioxidant activity effect of GS±SC. The following experimental techniques were used to evaluate the antioxidant efficacy of GS±SC. HPLC chromatogram, heavy metal content, ABTS/DPPH radical scavenging analysis, SOD-like activity assay, FACS, and NO assay. As a result of the experiment, the sinomenine content was found to be higher in DW extracts, and decursin was found to be higher in 80% ethanol extracts. And, the amount of heavy metals in all extracts was below the standard value. ABTS, and DPPH radical scavenging activity was identified that GS±SC(EtOH) was found to have a higher scavenging activity than GS±SC(DW). But, SOD showed the opposite result. No cytotoxicity of GS was observed on Raw 264.7 cells at concentration of 1~100 ㎍/㎖. The ROS production was significantly decreased that GS±SC(DW) was found to have a higher scavenging activity than GS±SC(EtOH). However, NO production showed the opposite result. Looking at the results of SOD and ROS analysis, SC does not seem to have a function of prevention. SC is thought to have an effect on the removal of free radicals generated after oxidative stress. This result objectively confirmed the antioxidant effect of GS±SCs. We will continue to conduct in-depth research. Therefore, it is believed that the possibility of using GS±SCs as a functional material can be established. The more diverse the objectives, the higher the value of GS utilization is thought to be.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.238-243
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• 2018

This study aimed to compare total phenolic, total flavonoid, and vitamin C contents, antioxidant capacities, and sensory characteristics of jangachi made from green kiwifruit (Actinidia deliciosa cv. Hayward) and golden kiwifruit (A. chinensis cv. Hort16A), which were cured with doenjang and kochujang. Golden kiwifruit had higher total phenolic, total flavonoid, and vitamin C contents, and antioxidant capacities than green kiwifruit. Jangachi of both cultivars of kiwifruit had generally higher total phenolic and flavonoid contents, and antioxidant capacities than fresh kiwifruit. Doenjang jangachi of kiwifruit had higher total phenolic contents and antioxidant capacities than kochujang jangachi. Jangachi made from golden kiwifruit cured with kochujang, following pretreatment with sugar solution, had the highest overall quality on sensory evaluation among jangachies tested herein. Together, our findings suggest that kiwifruit jangachi may serve as a good dietary source of phenolics and antioxidants.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.72-76
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• 2016

We investigated the application of functional materials by examining a variety of physiological activities of Geranium krameri extract obtained from the National Institute of Horticultural and Herbal Science. Geranium krameri extract had a low cytotoxicity against murine melanoma B16F10 cells. At concentrations with little or no cytotoxicity, Geranium krameri extract showed high DPPH radical scavenging activity ($IC_{50}$, $8.72{\mu}g/mL$) and anti-microbial activities against Bacillus subtilis, Escherichia coli, and Candida albicans. Additionally, Geranium krameri extract inhibited tyrosinase activity ($IC_{50}$, $456.86{\mu}g/mL$) and decreased melanin content ($IC_{50}$, $50.35{\mu}g/mL$). The treatment of B16F10 cells with Geranium krameri extract suppressed the protein expression of tyrosinase in a dose-dependent manner. These findings suggest that Geranium krameri extract inhibits melanin synthesis in murine melanoma B16F10 cells by suppressing intracellular tyrosinase expression, as well as directly inhibits tyrosinase activity simultaneously.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.10-17
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• 2017

The natural preservative "complex Scutellaria baicalensis extract (BHC)" contains Scutellaria baicalensis, Glycyrrhiza uralensis (liquorice), Zizyphus jujube (jujube), and Astragalus propinquus (milk vetch root). BHC has been used as a natural preservative for more than 10 years to increase storage duration and quality of food with strong antibacterial activity. BHC has been added into functional foods as a subsidiary ingredient. However, no studies have been performed to test whether or not BHC affects the activity of main functional ingredients. In this study, we tested whether or not BHC has any effect on the hepatoprotective activity of lactic acid-fermented garlic extract (LAFGE) when formulated in a clinical test supplement. $H_2O_2-induced$ oxidative damage in HepG2 cells was not attenuated by BHC, indicating that BHC had no influence on the protective effect of LAFGE against oxidative damage. Furthermore, BHC had no effect on the hepatoprotective effect of LAFGE against acetaminophen-induced acute liver injury in rats, as indicated by no changes in alanine transaminase and aspartate transaminase levels. In conclusion, BHC, formulated in the clinical test supplement with LAFGE, had no effect on hepatoprotective activity, indicating BHC could be considered as a suitable natural preservative for liquefied functional food materials.

• The Korean Journal of Mycology
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• v.40 no.2
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• pp.114-117
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• 2012

For development of new bioactive compounds from main edible mushrooms, we determined some physiological functionalities of water extracts from mushrooms. Among water extracts from some mushroom fruiting bodies, water extracts from Pleurotus ostreatus showed 73.2% of anti-hypertensive angiotensin I-converting enzyme inhibitory activity and 73.3% of anti-gout xanthine oxidase inhibitory activity, respectively. Fibrinolytic activity was also showed 21.5 mm of clear zone in water extract of Lyophyllum cinerascens. However, the other physiological functionalities were very weaked except 40.3% of antioxidant activity in Lentinus lepideus. Furthermore, the water extracts of Pleurotus eryngii and Lyophyllum cinerascens showed high anti-osteoporosis osteoclast differentiation inhibitory activity. However, the water extract from Lentinus lepideus and Pleurotus ostreatus were not detected any osteoclast differentiation inhibitory activity.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.209-215
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• 2018

To evaluate the radical scavenging activity of phenolic-rich fractions of Gardenia jasminoides, we first measured the levels of total polyphenols in hexane, ethyl acetate, and butanol fractions from the extract of G. jasminoides. The ethyl acetate fraction of G. jasminoides extract (GJ-EA) showed high level of phenolics, potent reducing power, and 2,2-diphenyl-1-picrylhydrazyl/2,2'-azino-bis 3-ethylbenzothiazoline-6-sulfonic acid radical scavenging effect. In addition, GJ-EA inhibited the overproduction of nitric oxide in lipopolysaccharide-activated BV-2 microglia. Furthermore, we found that GJ-EA suppressed $H_2O_2$-induced PANC-1 pancreatic cancer cell proliferation in a concentration-dependent manner and also reduced their migratory ability. These results suggest that GJ-EA may be a good source for functional foods with antioxidant and chemo-preventive activities.

• Journal of the Korean Geosynthetics Society
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• v.20 no.4
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• pp.1-7
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• 2021

In response to the carbon emission reduction trends and the depletion of natural sand caused by the use of cement in construction works, graphene oxide and porous feldspar were applied as countermeasures in this study. By using (3-aminopropyl)trimethoxysilane-functionalized graphene oxide with enhanced bond characteristics, a concrete specimen was prepared with 5% less cement content than that in a standard mortar mix, and the compressive strengths of the specimens were examined. The compressive strengths of the specimen with (3-aminopropyl)trimethoxysilane-functionalized graphene oxide and porous feldspar and the specimen with standard mixing were 26MPa and 28MPa, respectively, showing only a small difference. In addition, both specimens met the compressive strength of cement mortar required for geotechnical structures. It is believed that a reasonable level of compressive strength was maintained in spite of the lower cement content because the high content of pozzolans, namely SiO₂ and Al₂O₃, in the porous feldspar enhanced the reactions with Ca(OH)₂ during hydration, the nano-sized graphene surface acted as a reactive surface for the hydration products to react actively, and the strong covalent bonding of the carboxyl functional group increased the bonding strength of the hydration products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.1
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• pp.60-66
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• 2014

The aim of this study was to evaluate the antioxidant activity and protective effect of extracts from the stems and leaves of Chrysanthemum boreale (CBSL) on t-BHP induced oxidative stress in human liver cells (Chang cells). Antioxidant activities in the extracts were determined for various radical scavenging activities including ferric reducing antioxidant power, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity, and oxygen radical absorbance capacity (ORAC). CBSL showed a very good scavenging effect of DPPH radical ($IC_{50}$ $0.009{\pm}0.002$ mg/mL), alkyl radical ($IC_{50}$ $0.004{\pm}0.001$ mg/mL), and hydroxyl radical ($IC_{50}$ $6.742{\pm}0.152$ mg/mL). CBSL also showed a strong antioxidant effect in the ORAC assay. In the MTT assay on human liver cells (Chang cells), the extracts showed protective effects by increasing cell viability, decreasing ROS, and restoring mitochondria membrane potential upon t-BHP induced oxidative stress. Our findings suggest that CBSL extracts are a potential therapeutic with protective antioxidant effects upon oxidative stress.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.68.2-68.2
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• 2017

인체접촉시 니켈도금의 알러지 반응을 억제하기 위한 대체 도금기술인 비 시안계 Cu-Sn 합금도금을 개발함에 있어서, 황산구리5수화물과 황산제일주석을 금속염으로 하여 황산 및 계면활성제, 유화제 등을 포함한 각종 유기첨가제를 포함하였고 특히 은백색조의 외관 색상과 안정적인 Cu-Sn 합금전착을 위해 2종의 착화제인 EDTP (Ethylenediaminetetrapropanol, $C_{14}H_{32}N_2O_4$)와 TEA (Triethanolamine)를 첨가한 비 시안계 Cu-Sn 합금 도금액을 도출하였다. Cu-Sn 합금도금 피막 조성의 균일화를 도모하기 위해서는 합금 도금액중의 Cu와 Sn 금속이온 농도를 일정하게 유지하는 것이 필요하다. 그러나 합금 도금액 중 2가 주석이온($Sn^{2+}$)은 수용액 중에서 4가 주석이온($Sn^{4+}$)으로 산화됨으로써 도금액 색상이 백탁이 되고 Stannic Hydroxide($Sn(OH)_4$, $SnO_2{\cdot}2H_2O$)이 생성되어 대량의 침전물이 침강하는 문제점이 발생되는 등시간 경과에 따른 도금액의 경시 변화가 발생되었다. 상기 침전물은 연속여과에 의해 제거 가능하나 합금 도금액 중 $Sn^{2+}$ 농도가 지속적으로 감소하게 된다. 이는 합금 도금액 중 금속이온 비율이 변동함으로써 합금도금 피막의 조성비를 일정하게 유지하는 것이 곤란해진다. 이에 $Sn^{4+}$ 침전물 생성을 방지하기 위한 산화방지제를 개발하고 또한 산화방지제의 첨가에 따른 도금 피막 외관에 미치는 영향을 평가하여 외관 개선을 위한 광택제를 개발하고자 한다. 본 연구의 결과를 토대로 니켈도금과 동등 이상의 기능 특성을 갖는 비 시안계 Cu-Sn 합금도금액을 개발하여 실용화하는 것을 목적으로 하였다.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.37-37
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• 2003

탄소-탄소 복합체는 가벼우면서 고온에서도 강도의 저하가 적은 특성을 가지고 있어 터빈 블레이드 소재, 우주왕복선의 내열타일 등 광범위 한 고온재료로 응용이 이루어지고 있거나 기대되는 소재이다. 그러나 고온 산화분위기에서 쉽게 산화되는 단점이 있어 이러 한 산화특성을 향상시키는 방법으로 SiC, Si$_3$N$_4$ 등 내산화 저항성이 우수한 재료를 탄소-탄소 복합체 위에 코팅하는 연구가 행해지고 있다. 하지만 이들 코팅층과 탄소-탄소 복합체간의 열팽창계수 차이에 의한 열응력 발생으로 코팅층에 균열이 발생한다. 따라서 탄소-탄소 복합체와 코팅층간의 열응력을 최소화하여 균열 발생을 억제하기 위해 기능경사재료 (Functionally Graded Material, FGM)를 중간층으로 도입하는 방법이 최근 활발히 연구되고 있다. FGM 중간충의 형성방법 중 화학기상증착법 (CVD)은 증착물의 조성이나 미세구조 조절이 용이한 방법으로 알려져 있어 최근 CVD법에 의한 FGM층의 형성에 많은 연구가 진행되고 있지만, 지금까지 CVD법을 이용한C/SiC FGM 중간충의 형성 연구결과에서는 모든 조성비의 C/SiC층의 증착과 치밀한 구조를 지닌 증착층을 얻기가 어려워 체계적인 연구의 진행이 어려웠다.