• Journal of Microbiology and Biotechnology
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• 제14권4호
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• pp.673-679
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• 2004

A microbial cryoprotectant formulation using a W/O/W multiple emulsion system was developed. The psychrotolerant microorganism, B4, isolated from soil in South Korea, was observed by the drop freezing method, in which the microorganism sample inhibited ice nucleation activity. The antifreeze activity was eliminated when the microorganism sample was treated with protease, indicating that the antifreeze activity was due to the presence of antifreeze protein. The result of the l6S rDNA sequencing indicated the B4 strain was most closely related to a species of the genus Bacillus. Culture broth of B4 strain (Bacillus sp.) and rapeseed oil containing 1 % polyglycerine polyricinolate (PGPR) were used as core and wall material, respectively. The most stable W/O emulsion was prepared at a core/oil ratio of 1:2. The highest W/O/W emulsion stability was achieved when the primary emulsion to external aqueous phase containing 0.5% caster oil polyoxyethylene ether $(COG25^{TM})$ ratio was 1:1. Microcrystalline cellulose showed better W/O/W emulsion stability than other polymer types. The viability of cells in a W/O/W emulsion was higher than free cells during storage at $37^\circ{C}$. An acidic pH and UV exposure decreased the viability of free cells, but cells in W/O/W emulsion were more stable under these conditions.

• Natural Product Sciences
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• 제6권4호
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• pp.155-160
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• 2000

Testosterone deficiency increased bone resorption, giving rise to osteoporosis. Testosterone deficiency also increased lipid peroxidation and free radical formation. Free radicals have been shown to be toxic to osteoblasts as well as to activate osteoclasts. In this study, the effects of giving an antioxidant, i.e. vitamin E-rich extract from palm oil on bone mineral density and calcium content was studied. Palm vitamin E prevented the loss in bone mineral density due to orchidectomy, seen in the whole femur, proximal amd midshaft regions, as well as L4 vertebra. Similar observations were seen in bone calcium content of the L5 vertebra. Giving palm olein also prevented the loss in bone mineral density in the femoral midshaft and L4 vertebra; and bone calcium content in the L5 vertebra. In conclusion, vitamin E-rich extract from palm oil was effective in preventing the loss in bone mineral density and calcium content of orchidectomized male rats. This action is probably due to its role as an antioxidant.

• 동아시아식생활학회지
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• 제20권3호
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• pp.396-401
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• 2010

본 연구는 농산부산물인 왕겨, 보리외피, 대두외피에 적당한 열처리 및 활성화 처리를 하여 다양한 크기의 다공성 표면을 가진 회화재 및 활성탄 형태의 흡착제를 제조하여 식용유지의 불순물인 유리지방산과 색소 성분인 lutein에 대한 흡착 효과를 살펴보았다. 회화재 형태의 흡착제인 왕겨 회화재(RHA), 보리외피 회화재(BHA), 대두외피 회화재(SHA)는 처리 농도가 증가할수록 유리지방산 흡착 효과도 증가하여 대두 유의 산가가 감소하였는데 SHA와 BHA의 유리지방산 흡착효과가 컸고 RHA와 실리카의 효과는 작았다. SHA와 BHA는 5% 처리시 탈검 대두유의 산가를 82~86% 감소시킨데 비해 RHA는 29%, 실리카는 19% 감소시켰다. 회화재 형태의 흡착제 처리와 달리 활성탄 형태의 흡착제인 왕겨 활성탄(RHC), 보리외피 활성탄(BHC), 대두외피 활성탄(SHC)은 처리 농도를 증가시켜도 유리지방산 흡착 효과가 증가하지 않았다. RHC는 5% 처리시 탈검 대두유의 산가를 16%, BHC와 SHC는 8~10% 감소시켰으나, 상업용 활성탄은 거의 영향을 주지 않았다. 흡착제 종류별 lutein 제거 효과에서는 회화재 형태의 흡착제의 경우 7~8%의 미미한 감소를 보인 반면, 활성탄 형태의 흡착제의 경우 5% 처리 농도에서 RHC는 56%로 가장 큰 흡착 효과를 보였고, BHC는 41%, SHC는 52%, 상업용 활성탄은 49%의 lutein 함량 감소를 나타냈다. 따라서 lutein에 대한 흡착 효과는 회화재 형태의 흡착제보다 활성탄 형태의 흡착제가 훨씬 뛰어남을 알 수 있었다. 회화재 형태의 흡착제들은 비표면적과 전체 세공 부피는 작으나 세공의 크기가 큰 중간 세공이나 거대 세공으로 주로 이루어져 있고, 이런 특성이 유지 중에 불순물로 함유되어 있는 유리지방산 흡착과 관련이 있는 것으로 보인다. 반면에 색소 성분인 lutein은 회화재 형태의 흡착제 처리에서는 거의 감소 효과가 없고 활성탄 형태의 흡착제에서 감소 효과를 보인 것으로 보아 미세 세공에 흡착되는 특성이 있는 것으로 보인다. 따라서 흡착제를 이용하여 식용유지를 정제할 때는 회화재 형태와 활성탄 형태의 흡착제들을 혼합하여 사용하면 유리지방산과 lutein을 동시에 제거할 수 있을 것이다.

• 한국식품영양과학회지
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• 제10권1호
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• pp.77-84
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• 1981

The effect of sesame of L-lysine HCI and sesame supplementing a wheat flour diet on growth, liver lilpid content, and on the free amino acid levels in the plasma and liver was studied in young male rats with an initial body weight of $75{\pm}3g$. The free amino acids were analyzed by amino acid auto analyzer (JLC - 6HA, NO. 310). The results were as follows. The body weitht gain on L-lysine HCI and sesame supplemented diet was more than weight in the sesame added diet or wheat flour diet groups. Also the liver lipid contents of rats on a wheat flour diet supplemented with L-lysine HCI and sesame showed greater increases than the levels in rats on the wheat flour diets. The rate of liver lipid accumulation was depressed in rats fed L-lysine HCI supplemented wheat flour containing sesame than in rats fed soybean oil or shortening oil instead of sesame. The free phe. Tyr. Leu. Ileu. Val. Lys. levels in the plasma of rats administered the wheat flour diets supplemented with 0.25% L-lysine HCI were higher than those of rats without L-lysine HCI. The free phe. Tyr. Asp. His. Lys. contained in the liver were increased, but other free amino acids were decreased according to the L-lysine HCI amount.

• 한국식품위생안전성학회지
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• 제7권2호
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• pp.107.1-112
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• 1992

Free-, soluble- and insoluble phenolic acids were extracted from defatted Galla Rhois. The extracts were then dissolved in equal amounts of an soybean oil, and POV (peroxide value) of the resulting substrates, portion of the soybean oil (control) and 0.02% BHT were measured by AOM (active oxygen method) test at 97.8$^{\circ}C$ for 40 hours through Rancimat method. Induction period of control, BHT, free phenolic acids, soluble phenolic acids and insoluble phenolic acids by the Rancimat method were 4.8, 10.5, 23.9 and 30.5hr. The phenolic acids separated and tentati-vely identified by gas chromatography were catechol, gallic acid, vanillin, protocatechuic acid, syri-ngic acid, ferulic acid.

• 한국유체기계학회 논문집
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• 제5권1호
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• pp.55-61
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• 2002

The feasibility of an oil-free, motor-driven, two-stage centrifugal compressor supported by air bump bearings is investigated. This centrifugal compressor is driven by a 75 kW motor at an operating speed of 39,000 RPM, and a pressure ratio of the compressor is set up to 4. The analysis is performed by using bearing equilibrium position, heaving stillness, Campbell diagram, unbalance response, and stability. It is demonstrated in this paper that air bump bearings can be adopted well to an oil-free, motor-driven, centrifugal compressor. Specially, Cu-coated bump bearings have enough damping force to reduce a synchronous unbalance for rigid modes of the two-stage compressor. Futhermore, this concept may be applied to the flexible rotor system such as high speed turbomachinery with a super critical speed.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.469-474
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• 2001

The feasibility of a oil-free motor-driven two-stage centrifugal compressor supported by air bump bearings is investigated. This centrifugal compressor is driven by 75kW motor at an operating speed of 39,000RPM md a pressure ratio of the compressor is up to 4. The analysis is performed, based upon bearing equilibrium position, bearing stiffness, Campbell diagram, unbalance response and stability. It is demonstrated in this paper that air bump bearings can be adopted well to a oil-free motor-driven centrifugal compressor.

• 대한가정학회지
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• 제36권1호
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• pp.1-11
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• 1998

The purpose of this study is to find troubles in producing and using the reclaimed soaps to get the solutions of their troubles. Five kinds of reclaimed soaps were taken from religious or civic organizations and nine kinds of soaps were made by adding sodium hydroxide of different concentrations to the used vegetable oil in our laboratory. Washing efficiency, pH test, BOD, and skin irritability of the reclaimed of manufactured soaps were examined. The washing efficiency of the manufactured soaps were ±80%. The percent of free-alkali tended to increase as the amount of NaOH increased. The skinirritability was proportional to the amount of NaOH added. To make the reclaimed soap, the best percent of NaHO to used oil is 17% or 18% and this ratio(17%∼18%) should be kept. Manufactured soaps by this ratio have good apperance condition and washing efficiency. And also they have low skin irritability and free-alkali. This study has the limitations that the skin irritability test can have individual and the collected soaps couldn't represent all kinds of recaimed soap.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.572-577
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• 2006

Numerical simulation has been made on the performance of an oil free air compressor for automotive electronic air suspension system. Calculation results on the flow rate at various air supply pressures were reasonably well compared to the experimental data. With the aid of the computer simulation program, parametric study on the compressor design parameters has also been carried out for the compressor performance improvement: Increase in the discharge port diameter or discharge valve stiffness was found to be effective to increase the flow rate per unit compressor input for the present compressor model.

• Applied Biological Chemistry
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• 제37권3호
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• pp.168-174
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• 1994

여과 및 원심 분리가 $70^{\circ}C$ 저장 중 참기름의 산화 안정성에 미치는 영향을 headspace gas chromatography법에 의한 헥산알 생성과 기름의 과산화물가 및 공액 이중 결합 측정에 의해 살펴보았다. 볶은 참깨로부터 얻은 조참기름은 유리지방산, 공액 이중결합과 금속(철, 구리, 마그네슘 및 아연)을 더욱 많이 함유한 반면 수분과 ${\gamma}-tochopherol$은 여과 참기름 또는 원심분리 참기름에 더 많이 함유되었다. 여과 참기름은 세 종류의 기름 중 가장 큰 L과 b값의 우수한 색도에도 불구하고 조참기름보다 많은 과산화물을 함유하였다. 모든 참기름이 $70^{\circ}C$ 저장 중 색차가 증가하는 경향을 보였으며 여과 참기름에서의 리놀렌산 감소 경향을 제외하고는 비교적 일정한 지방산 조성을 보였다. 산화 안정성에 있어서 원심분리 참기름과 조참기름은 a=1%에서 유의적인 차이를 보이지 않았으며 여과 참기름은 이들보다 산화안정성이 떨어졌다. 원심분리 참기름이 산화안정성과 유지의 색도 측면에서 가장 좋은 것으로 나타났다.