식물성 질소원의 보충이 면양에 의한 볏짚의 소화율에 미치는 영향

이희섭,강희신 ( Hee Seob Lee,Hi Shin Kang ) 한국축산학회 1980 한국축산학회지 Vol.22 No.2

Three Corridale male sheep were fed each of the three diets; Acacia leaf hay alone (AL), chopped rice st raw plus near isonitrogeneous quantity of Soybean oil meal (RS) or Acacia Leaf Hay(RA) according to a Latin square design to studs the effect of supplemental nitrogen on the digestibilities of nutrients and the voluntary intake of rice straw. The results obtained from the above trial were summarized as follows: (1) The voluntary feed intake of acacia leaf hay was found to he 935g/day and its digestibility of dry matter, crude protein and crude fibre were 51.8, 46.0 and 52.0% respectively. (2) Although the total UM intake were not affected by the supplemental nitrogen sources, the intake of chopped rice straw by the sheep at the RS was 11.7% higher thar that of RA. (3) The crude protein intake of sheep at the AL was higher (p. 05) than those of RS and RA. The crude protein digestibility of RS, however, was higher than those of AL and RA as much as 71.7% and 64.2%. (4) Despite the trend that the liber intake of sheep fed chopped rice straw, RS and RA, were higher than that of AL as much as 49.3% and 64.3% the digestibility of crude fiber showed no significant difference among the treatments. The difference between the RS and AL., however, was significant at level of 10% probability. The total digestible nutrients of chopped rice straw was calculated to be 50% in DM basis by employing the TDN value of known Soybean oil meal and Acacia leaf hay.

유산균 발효 마늘 추출물의 oleic acid로 유도된 비알코올성 지방간에 대한 개선 효과

이희섭(Hee-Seop Lee),임원철(Won-Chul Lim),최지휘(Ji-Hwi Choi),유희종(Heui-Jong Yu),김기호(Ki-Ho Kim),이승현(Seung-Hyun Lee),조홍연(Hong-Yon Cho) 한국식품과학회 2014 한국식품과학회지 Vol.46 No.6

본 연구에서는 oleic acid로 유도시킨 비알코올성 지방간 HepG2 세포 모델을 활용하여 LAFGE의 비알코올성 지방간 개선 효과를 검토하고 RT-PCR과 Western blot으로 메카니즘을 해석하였다. LAFGE는 1 mg/mL 농도에서 NFGE보다 세포 내 지방축적을 약 1.5배 저해하였다. Fig. 5에 나타낸 바와 같이 LAFGE는 FAT/CD36 mRNA 발현을 감소시켜 세포 내로 유입되는 지방산의 양을 감소시켰으며, PPARα와 CPT-1의 mRNA 발현을 증강시킴으로써 지방산의 베타-산화를 촉진시켰다. 또한 LAFGE는 지방합성을 촉진하는 전사인자인 SREBP-1c와 그의 조절을 받는 FAS의 mRNA 발현 수준을 oleic acid 처리시보다 각각 51%와 35% 까지 크게 감소시켰다. 뿐만 아니라 LAFGE는 농도의존적으로 SREBP-1c와 FAS의 단백질 발현도 감소시켰다. 이 결과들은 LAFGE가 oleic acid처리에 의해 유도된 HepG2 세포 내의 지방 축적을 개선할 수 있음을 시사하였다. In this study, the ameliorating effects of lactic acid-fermented garlic extract (LAFGE) on non-alcoholic fatty liver were investigated using oleic acid-induced steatotic HepG2 cells. The ameliorating mechanism was analyzed by RTPCR and Western blot. Treatment with 1 mg/mL LAFGE decreased intracellular lipid accumulation approximately 1.5-fold, compared to that achieved with non-fermented garlic extract. LAFGE reduced fatty acid influx into hepatocytes through down-regulation of FAT/CD36 mRNA expression in the steatotic HepG2 cells. PPARα and CPT-1 mRNA expression was significantly up-regulated by LAFGE treatment of HepG2 cells as a consequence of activation of beta oxidation. Additionally, the treatment with 1 mg/mL LAFGE highly down-regulated mRNA expression of SREBP-1c and FAS to 51% and 35%, respectively. LAFGE showed concentration-dependent down-regulation patterns in protein expression of SREBP-1c and FAS, as determined by Western blot. These results suggest that LAFGE treatment improves hepatic steatosis triggered by the imbalance of hepatic lipid metabolism owing to oleic acid treatment.

참치 자숙액의 항산화 활성에 감마선 조사가 미치는 영향

이희섭(Hee-Sub Lee),김현주(Hyun-Joo Kim),최종일(Jong-il Choi),김재훈(Jae-Hun Kim),김진규(Jin-Gyu Kim),전병수(Byung-Soo Chun),안동현(Dong-Hyun Ahn),정영진(Young-Jin Chung),김영지(Yeung-Ji Kim),변명우(Myung-Woo Byun),이주운(Ju-Woon Lee 한국식품영양과학회 2008 한국식품영양과학회지 Vol.37 No.6

수산 가공 폐기물중 하나인 참치 자숙액을 이용하여 천연기능성 소재 개발을 하기 위해 참치 자숙액 에탄올 추출물에 감마선 조사(0, 50 kGy)를 하여 전자공여능을 확인하고, FRAP, UWLA, Rancimat 등을 사용하여 항산화 활성 변화에 관하여 알아보았다. 감마선 조사한 참치 자숙액의 전자공여능 및 hydroxyl 라디칼 소거능 측정 결과 감마선 조사에 의해 각각 16.17% 및 10.38% 증가하였고, 산화안정지수 및 FRAP value 또한 각각 23% 및 26% 증가하였다. β-carotene bleaching assay를 이용하여 항산화지수를 측정한 결과 감마선 조사에 의해 항산화지수가 증가하는 경향을 보였다. 이러한 결과로 미루어 볼 때 참치 자숙액 자체가 가지고 있는 항산화 활성 및 산화안정성을 감마선 조사 기술을 사용하여 증진시켜 식품 및 공중보건산물의 첨가제로서의 이용이 가능할 것이라 사료된다. This study was conducted to examine the effect of a gamma irradiation on the antioxidant activity of ethanol extract from cooking drips of Thunnus thynnus (ECT). The electron donating ability against 1,1-diphenyl-2-picryl-hydrazyl (DPPH), authentic hydroxyl radical scavenging activity by Ultra Weak Luminescence Analyzer, oxidative protection factors by Racimat method, ferric reducing antioxidant power (FRAP), and β -carotene bleaching activity were measured as indices of antioxidant activity. All of the results shown that irradiation increased the antioxidant activity of ECT. These results suggested that ECT could be used as an antioxidative component in food and gamma irradiation could enhance these antioxidative properties.

논문편 : 침채류와 과실의 연화현상에 관한 고찰

이희섭 ( Hee Seoup Rhee ) 대한가정학회 1996 Family and Environment Research Vol.34 No.4

침채류의 조직감 측정방법

이희섭 ( Hee Seoup Rhee ) 한국식품조리과학회 1995 한국식품조리과학회지 Vol.11 No.1

For the accurate interpretation and objective measurement of textural characteristics of fermented vegetables, first of all, the studies on the microstructure and chemical compositions of vegetable cell, and the changes in the textural properties of vegetables during salting, blanching and fermentation should be carried out. And the mechanical textural parameters were needed to compare with and analyze in relation to the sensory parameters. In this review, the thypical force-distance curves of fermented vegetables were obtained from the compression, cutting and puncture tests. And it was showed that the compression force was a more effective textural parameter to express the hardness of fermented vegetables, and the sensory chewiness and toughness were related to the changes in cutting force. In the puncture test, the puncture force was related to the hardness and varied with the size and form of puncture probe; the changes in puncture force by small probe could express the decrease in hardness and crispness, whereas those by large probe could represent the changes in toughness. And the brittleness and crispness could be measured by the break point and the numbers of peak obtained from the force-distance curves.

천연보존료 복합 황금추출물이 유산균발효 마늘추출물의 저장성 및 기능성에 미치는 영향

이희섭(Hee-Seop Lee),이성진(Sun-Jin Lee),손요한(Johann Sohn),유희종(Heui-Jong Yu),조홍연(Hong-Yon Cho) 한국식품영양과학회 2017 한국식품영양과학회지 Vol.46 No.1

본 연구는 유산균발효 마늘추출물의 간 보호 효능에 대해 천연보존료인 복합 황금추출물이 유산균발효 마늘추출물의 간 보호 효능에 미치는 영향 여부를 확인하기 위해 수행되었다. 복합 황금추출물은 H2O2에 의한 산화적 손상에 대한 유산균발효 마늘추출물의 간 보호 효능에 있어서 유의적인 영향을 미치지 않았으며, acetaminophen에 의한 급성 간 손상 동물 모델에서 시료에 첨가된 복합 황금추출물은 유산균 발효 마늘추출물의 간 손상 억제 효능에 있어 유의적인 영향을 미치지 않았다. 이상의 결과들을 종합 고찰할 때 복합 황금추출물은 기능성 원료의 유효성에 영향을 미치지 않으면서 액상제형 건강기능성식품의 안전성을 확보할 수 있는 천연보존제로 판단되었다. 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. H2O2-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.

고분자전해질 연료전지 분리판용 복합재의 전기적/기계적 특성

이희섭(Hee-Sub Lee),김성근(Sung-Geun Kim),안성훈(Sung-Hoon Ahn),전의식(Ui-Sik Jeon),안상열(Sang-Yeoul Ahn),안병기(Byung-Ki Ahn) 대한기계학회 2005 대한기계학회 춘추학술대회 Vol.2005 No.11

Fuel cell is one of promising environment-friendly energy sources for the next generation. The bipolar plate is a major component of the PEM fuel cell stack, which takes a large portion of the stack cost. In this study, as the alternative materials of bipolar plate of PEM fuel cells, graphite composites were fabricated by compression molding. P-15 particles were mixed with epoxy resin to provide electric conductivity and structural properties. To find out the most suitable electric properties, graphite composites were fabricated with different mixing ratio, processing pressure and temperature. By increasing mixing ratio and fabricated pressure, electric conductivity was improved due to the smaller gap between the particles. In addition, by increasing process temperature, the electric conductivity was also improved probably by the excited molecular activities and resulting low viscosity of the epoxy resin for better fill of the gaps. The results of mechanical test showed that the tensile strength of graphite composite was about 5㎫.

양수 및 신생아 첫소변의 트립신 저해능

이희섭 ( Hee Sub Lee ),홍기연 ( Gi Youn Hong ),이희민 ( Hee Min Lee ),이승준 ( Seung Jun Lee ),김원신 ( Won Shin Kim ) 대한주산의학회 1995 大韓周産醫學會雜誌 Vol.6 No.2

PEM 연료전지용 섬유강화 분리판의 특성 평가

이희섭(Lee, Hee-Sub),김성근(Kim, Sung-Geun),안성훈(Ahn, Sung-Hoon),전의식(Jeon, Ui-Sik),안상열(Ahn, Sang-Yeoul),안병기(Ahn, Byung-Ki) 한국신재생에너지학회 2005 한국신재생에너지학회 학술대회논문집 Vol.2005 No.11

The bipolar plate is a major component of the PEM fuel cell stack, which takes a large portion of stack cost. In this study, as alternative materials for bipolar plate of PEM fuel cells, graphite composites were fabricated by compression molding. Graphite particles mixed with epoxy resin were used as the main substance to provide electric conductivity. To achieve desired electric properties, specimens made with different mixing ratio, processing pressure and temperature were tested. To increase mechanical strength, one or two layer of woven carbon fabric were added to the original graphite and resin composite. Thus, the composite material is consisted of the three phases: graphite particles, epoxy resin, and carbon fabric. By increasing mixing ratio, fabricated pressure and process temperature, electric conductivity was improved. The results of tensile test showed that the tensile strength of two-phase graphite composite was about 5MPa, and that of three-phase composite was increased to 54MPa.

PEM 연료전지용 복합재 분리판의 제작비용 비교: 압축성형과 기계식 가공

이희섭(Lee, Hee-Sub),추원식(Chu, Won-Shik),강윤철(Kang, Yun-Cheol),강혁진(Kang, Hyuk-Jin),안성훈(Ahn, Sung-Hoon) 한국신재생에너지학회 2006 한국신재생에너지학회 학술대회논문집 Vol.2006 No.11

The fuel cell is one of the promising environment-friendly energy sources for the next generation. The fuel cell provides good energy efficiency above 40% without pollution or noise. Different fuel cell types are usually distinguished by the kind of electrolyte. Among these, the proton exchange membrane fuel cell (PEMFC) has advantages of high power density. low operating temperature, relatively quick start-up, and rapid response to varying loads. The bipolar plate is a major component of the PEM fuel cell stack, and it takes a large portion of stack volume, weight and cost. In this study, as alternative materials for bipolar plate of PEM fuel cells, graphite composites were fabricated by compression molding and by machining. Graphite particles mixed with epoxy resin were used as the main substance to provide electric conductivity. Flow channels were fabricated by compression molding with design of experiments (DOE) to evaluate moldability. The cost for compression molding of graphite-composite bipolar plate was compared with machining cost to make the same bipolar plate.