• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1114-1123
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• 2015

Bushing is the key link to connect outer and inner insulating systems and also the essential electric accessory in electric power system, especially in the high voltage engineering (AC 1000kV, DC 800kV). This paper presented the experimental research of thermal aging characteristic of oil-paper insulation used in bushing. A thermally accelerated aging experiment at 90℃ was performed. The bushing models containing five layers of paper were sealed into the aging vessels and further aged for 250 days. Then several important parameters associated with the aging were observed and evaluated. The results showed that the degree of polymerization (DP) of papers gradually decreased. The DP values of outermost layer and middle layer fit well into the second-order kinematic model and first-order kinematic model, respectively. Less deterioration speed of the inter-layer paper than outer layer was confirmed by the variation of DP. Hydrolysis was considered as the main cause to this phenomenon. In addition, the logarithm of the furfural concentrations in insulation oil was found to have good linear relationship with DP of papers. Interestingly, when the aging time is about 250 days and DP is 419, the aging process reaches an inflection point at which the DP approaches the leveling off degree of polymerization (LODP) value. Both tanδ and acid number of oils increased, while surface and volume resistivity of papers decreased. The obtained results demonstrated that thermal aging and moisture absorbed in papers brought great influence to the degradation of insulating paper, leading to rapid decrease of DP and increase of the tanδ. Thus, the bushing should be avoided from damp and real-time monitoring to the variation of tanδ and DP values of paper is an effective way to evaluate the insulation status of bushing.

• Preventive Nutrition and Food Science
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• 제15권2호
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• pp.98-104
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• 2010

The seeds from two mulberry fruits [Morus alba (MA) and Cudrania tricuspidata (CT)] were examined for their oil content, and fatty acid, phytosterol and tocopherol compositions and contents. Moreover, polyphenolic compounds and biological activity of the two defatted seed residue extracts were also evaluated. Oil contents of MA and CT seeds were 29.36% and 16.69%, respectively, while MeOH extracts of the defatted MA and CT seed residues were 5.10% and 6.22%, respectively. The two seed oils were composed of 81.4 and 74.37% linoleic, 5.75 and 11.39% oleic, 8.40 and 10.18% palmitic acid, and 3.52 and 3.0% stearic acids, and two other minor fatty acids, such as linolenic and arachidic acids. MA seed had higher contents of phytosterols (507.59 mg/100 g of oil), tocopherols (99.64 mg/100 g of oil), and total flavonoid (106.50 mg/100 g of seed) than CT seed, whereas CT seed had higher levels of total polyphenol than MA seed. The MeOH extract of MA seed residue showed higher antioxidant, anti-diabetic, and anti-melanogenic activity than that of CT seed residue. trans-Resveratrol (9.62 mg/100 g), quercetin (54.83 mg/100 g), and 4-prenylmoracin (48.70 mg/100 g), were found to be the main polyphenolic components in the MeOH extract of MA seed residue. These results indicate that MA seeds are good sources of essential dietary phytochemicals with antioxidant, anti-diabetic and anti-melanogenic activity.

• Journal of Dairy Science and Biotechnology
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• 제30권2호
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• pp.75-81
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• 2012

Molds cause severe cheese deterioration, even though some white and blue molds are used for the manufacture of Camembert and Blue cheese, respectively. The species of Geotrichum, Moniliella, Aspergillus, Penicillium, Mucor, Fusarium, Phoma, and Cladosporium are the main fungi that affect contamination during cheese ripening. Once deteriorated by fungal spoilage, cheese becomes toxic and inedible. Fungal deterioration of cheese decreases the nutritional value, flavor profiles, physicochemical and organoleptic properties, and increases toxicity and infectious disease. Fungal contamination during cheese ripening is highly damaging to cheese production in Korean farmstead milk processing companies. Therefore, these companies hesitate to develop natural and ripened cheese varieties. This article discusses the recent and ongoing developments in the removal techniques of fungal contamination during cheese ripening. There are 2 categories of antifungal agents: chemical and natural. Major chemical agents are preservatives (propionic acid, sodium propionate, and calcium propionate) and ethanol. Among the natural agents, grapefruit seed extract, phytoncide, essential oils, and garlic have been investigated as natural antifungal agents. Additionally, some studies have shown that antibiotics such as natamycin and Delvocid$^{(R)}$, have antifungal activities for cheese contaminated with fungi. Microbial resources such as probiotic lactic acid bacteria, Propionibacterium, lactic acid bacteria from Kimchi, and bacteriocin are well known as antifungal agents. In addition, ozonization treatment has been reported to inhibit the growth activity of cheese-contaminating fungi.

• Natural Product Sciences
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• 제24권1호
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• pp.28-35
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• 2018

Pulegone is a naturally occurring organic compound obtained from essential oils from a variety of plants. The aim of this study was to investigate the anti-inflammatory effects through the inhibitory mechanism of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), nuclear factor kappa B ($NF-{\kappa}B$), mitogen-activated protein kinases (MAPK) pathways and the activation of nuclear factor erythroid 2-related factor 2 (Nrf2)/ heme oxygenase (HO)-1 pathways in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Results revealed that pulegone significantly inhibited NO production as well as iNOS and COX-2 expressions. Meanwhile, western blot analysis showed that pulegone down-regulated LPS-induced $NF-{\kappa}B$ and MAPKs activation in RAW 264.7 cells. Furthermore, the selected compound suppressed LPS-induced intracellular ROS production in RAW 264.7 cells, while the expression of stress response gene, HO-1, and its transcriptional activator, Nrf-2 was upregulated upon pulegone treatment. Taking together, these findings provided that pulegone inhibited the LPS-induced expression of inflammatory mediators via the down-regulation iNOS, COX-2, $NF-{\kappa}B$, and MAPKs signaling pathways as well as up-regulation of Nrf-2/HO-1 indicating that pulegone has a potential therapeutic and preventive application in various inflammatory diseases.

• 한국유기농업학회지
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• 제17권4호
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• pp.557-566
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• 2009

시판 마요네즈를 이용하여 오이 흰가루병에 대한 방제효과를 시험하였다. 마요네즈를 0.5~2% 농도로 물에 희석하여 흰가루병이 발병된 오이에 6일 간격 3회 처리했을 때 8.3~99.2% 방제효과를 나타내었다. 90% 이상의 방제효과를 보인 마요네즈 희석액 중 2-3엽의 어린모에서 약해가 없었던 농도는 0.5%이었다. 마요네즈 중 기름함량이 78~80% 수준인 일반 마요네즈와 기름함량을 38~70%로 줄인 저지방 마요네즈의 흰가루병 방제력을 비교했을때 저지방 마요네즈는 방제율은 39.3~59.8% 수준으로 일반마요네즈에 비해 방제율이 떨어졌다. 마요네즈가 처리된 잎의 엽록소 함량은 발병구에 비해 엽록소 함량이 약 3배 정도 높게 조사되어 처리된 마요네즈가 오이 잎의 광합성을 저해하지 않으면서 흰가루병을 효과적으로 방제함을 확인하였다.

• 한국식품과학회지
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• 제25권5호
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• pp.426-429
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• 1993

미분쇄와 배전처리가 숙성카레분의 향기성분 변화에 미치는 영향을 검토하기 위하여 각각을 6개월간 숙성시킨 후 GC 및 GC-MS를 사용하여 향기성분을 분리, 동정하였다. 숙성카레분의 주요 휘발성 향기성분은 terpene계 탄화수소, terpene계 alcohle 화합물, 방향족 ether 화합물로서 숙성전과 커다란 차이는 없었으나 미 분쇄시간 15분까지는 처리시간이 증가할수록 peak의 면적이 증가하다가 20분 이후에는 급격히 감소하는 경향을 보였고, 배전처리의 경우는 $70^{\circ}C$까지는 peak의 면적이 증가하다가 그 이후에는 감소하는 경향을 보여 $70^{\circ}C$에서 20분간 배전처리 한 후 숙성시키는 것이 가장 효과적인 것으로 나타났다.

• 한국식품과학회지
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• 제18권4호
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• pp.294-300
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• 1986

향신료에 오염된 미생물의 효과적인 살균 방법 개발을 목적으로 고추 및 후추가루를 시료로 하여 현행 방법인 ethylene oxide 훈증 처리와 감마선 조사에 따른 미생물의 살균 효과 및 이화학적 품질에 미치는 영향을 비교 검토하였다. 시료에 오염된 일반 세균, 내열성 포자균, 산저항성 세균, 곰팡이 및 내삼투압성 곰팡이와 대장균군은 7-10 kGy 의 감마선 조사로서 사멸이 가능하였으나 훈증 처리구는 살균 효과가 다소 불충분하였다. 살균 처리는 시료의 이화학적 특성 즉, 향신성분, 색소, 정유 성분, 색도 등에 어느 정도 변화를 초래하였지만 훈증 처리는 감균 및 살균선량의 감마선 조사보다 영향이 큰 것으로 확인되었다.

• Biomolecules & Therapeutics
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• 제23권5호
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• pp.471-478
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• 2015

Colon cancer is considered as the precarious forms of cancer in many developed countries, with few to no symptoms; the tumor is often diagnosed in the later stages of cancer. Monoterpenes are a major part of plant essential oils found largely in fruits, vegetables and herbs. The cellular and molecular activities show therapeutic progression that may reduce the risk of developing cancer by modulating the factors responsible for colon carcinogenesis. Colon cancer was induced with DMH with a dose of (20 mg/Kg/body weight) for 15 weeks by subcutaneous injection once in a week. Myrtenal treatment was started with (230 mg/Kg/body weight) by intragastric administration, one week prior to DMH induction and continued till the experimental period of 30 weeks. The Invivo results exhibit the elevated antioxidant and lipid peroxidation levels in DMH treated animals. The Histopathological analysis of colon tissues well supported the biochemical alterations and inevitably proves the protective role of Myrtenal. Treatment with myrtenal to cancer bearing animals resulted in a remarkable increase in the inherent antioxidants and excellent modulation in the morphological and physiological nature of the colon tissue. It is thus concluded that myrtenal exhibits excellent free radical scavenging activity and anticancer activity through the suppression of colon carcinoma in Wistar albino rats.

• Journal of Ginseng Research
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• 제44권4호
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• pp.527-537
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• 2020

Panax ginseng, a medicinal plant, has been used as a blood-nourishing tonic for thousands of years in Asia, including Korea and China. P. ginseng exhibits adaptogen activity that maintains homeostasis by restoring general biological functions and non-specifically enhancing the body's resistance to external stress. Several P. ginseng effects have been reported. Korean Red Ginseng, in particular, has been reported in both basic and clinical studies to possess diverse effects such as enhanced immunity, fatigue relief, memory, blood circulation, and anti-oxidation. Moreover, it also protects against menopausal symptoms, cancer, cardiac diseases, and neurological disorders. The active components found in most Korean Red Ginseng varieties are known to include ginsenosides, polysaccharides, peptides, alkaloids, polyacetylene, and phenolic compounds. In this review, the identity and bioactivity of the non-saponin components of Korean Red Ginseng discovered to date are evaluated and the components are classified into polysaccharide and nitrogen compounds (protein, peptide, amino acid, nucleic acid, and alkaloid), as well as fat-soluble components such as polyacetylene, phenols, essential oils, and phytosterols. The distinct bioactivity of Korean Red Ginseng was found to originate from both saponin and non-saponin components rather than from only one or two specific components. Therefore, it is important to consider saponin and non-saponin elements together.

• 한국식품과학회지
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• 제26권4호
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• pp.359-364
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• 1994

야생식용식물인 메꽃의 식용부위에 따른 휘발성 풍미성분을 분석하기 위하여 SDE방법으로 정유성분을 분리한 다음 GC 및 GC-MS를 이용하여 성분을 확인하였다. 잎에서는 탄화수소류 21종, 알데히드류 1종, 케톤류 4종, 알콜류 7종, 에스테르류 4종, 유기산류 1종 및 기타 1종이 확인되었다. 줄기에서는 탄화수소류 16종, 알데히드류 2종, 케톤류 3종 및 알콜류 5종이 확인되었으며, 뿌리에서는 탄화수소류 26종, 알데히드류 2종, 케톤류 5종, 알콜류 13종, 에스테르류 1종, 유기산류 1종 및 기타 4종이 확인되었다. 잎과 중기에서보다 뿌리에서 확인된 휘발성 풍미성분의 종류가 더 다양하였고 잎과 줄기는 탄화수소류가 다량 함유된 반면 뿌리에는 신선한 풀내음과 달콤한 향을 부여하는 알데히드류, 케톤류 및 알콜류가 다른 부위보다 수(數)적으로나 양(量)적으로 다량 함유되어 있었다.