• Macromolecular Research
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• v.8 no.2
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• pp.80-88
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• 2000

Biodegradable microspheres were prepared with poly(L-lactide-co-glycolide) (PLGA, 75 : 25 by mole ratio) by an oil/oil solvent evaporation method for the sustained release of anti-AIDS virus agent, AZT The microspheres of relatively narrow size distribution (7.6$\pm$ 3.8 ㎛) were obtained by controlling the fabrication conditions. The shape of microspheres prepared was smooth and spherical. The efficiency of AZT loading into the PLGA microsphere was over 93% compared to that below 15% for microspheres by a conventional water/oil/water method. The effects of Preparation conditions on the morphology and in vitro AZT release pattern were investigated. in vitro release studies showed that different release pattern and release rates could be achieved by simply modifying factors in the fabrication conditions such as the type and amount of surfactant, initial amount of loaded drug, the temperature of solvent evaporation, and so on. PLCA microspheres prepared by 5% of initial drug loading, 1.0% (w/w) of surfactant concentration, and 25$\^{C}$ of solvent evaporation temperature were free from initial burst effect and a near-zero order sustained release was observed. Possible mechanisms of the near-zero order sustained release for our system have been proposed.

• Korean Journal of Food Science and Technology
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• v.47 no.5
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• pp.561-566
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• 2015

Effect of the addition of egg yolk lecithin at a concentration of 350 mg/kg on iron-catalyzed autoxidation and chlorophyll-photosensitized oxidation of a water/canola oil emulsion (W/O) during storage at $25^{\circ}C$ was studied based on headspace oxygen consumption and hydroperoxide production. Changes in the phospholipid (PL) composition of the emulsion were determined by high performance liquid chromatography. Headspace oxygen consumption and hydroperoxide content of the emulsion increased with storage time, and addition of egg yolk lecithin did not have any significant effect on these parameters during iron-catalyzed autoxidation and chlorophyll-photosensitized oxidation of the emulsion. PL content of the emulsion decreased during both oxidations, and the degradation rate was higher during autoxidation than during photosensitized oxidation. Phosphatidylcholine content ratio tended to increase during autoxidation. The results suggest that egg yolk lecithin in canola oil emulsion behaves differently during iron-catalyzed autoxidation and chlorophyll-photosensitized oxidation.

• KSBB Journal
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• v.26 no.4
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• pp.333-340
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• 2011

In this study, gemcitabine-loaded methoxy poly(ethylene glycol)-b-poly(L-lactide) (MPEG-PLLA) microparticles with different PEG block lengths were prepared by a W/O/W double emulsion technique. The present study focuses on the investigation of the influence of various preparative parameters such as the ratio of internal water phase and oil phase, polymer concentration, solvent composition of organic phase and salt concentration of external water phase on the morphology and encapsulation efficiency of the microparticles. The microparticles fabricated at high volume ratios of internal water phase to oil phase and at high polymer concentrations showed a relatively high encapsulation efficiency and low porosity. When a dichloromethane/ethyl acetate mixture was used as solvent, both the encapsulation efficiency and drug loading of the microparticles decreased as the level of ethyl acetate increased. The addition of a salt (NaCl) to the external water phase significantly improved the encapsulation efficiency up to 40%, and the microparticles became more spherical with their size and porosity decreased.

• Journal of Life Science
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• v.30 no.7
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• pp.606-613
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• 2020

This study investigated the effect of olive oil substitution ratio on physicochemical quality of pork patty. Five treatments were performed as follows: control (T0, 20% pork fat), T1 (pork fat 15% and olive oil gel 5%), T2 (pork fat 10% and olive oil gel 10%), T3 (pork fat 5% and olive oil gel 15%), and T4 (olive oil gel 20%). The moisture increased and fat amount was decreased in proportion to olive oil substitution ratio. The L^* and a^* values were highest levels in raw and cooked pork patty of T0, and the b^* value was highly enhanced in of cooked pork patty of T4. The water holding capacity, moisture and fat retention were significantly increased, and the cooking loss, diameter reduction and shrinkage ratio were decreased by olive oil substitution ratio. The hardness, springiness and chewiness showed the highest level in T4, and the cohesiveness and gumminess were highest in T0. The reduction ratio of cholesterol in T1, T2, T3 and T4 were 13.8%, 21.6%, 34.5% and 49.0%, respectively, indicating that the content was lowest level in T4. The palmitic acid was the most abundant saturated fatty acid, and the oleic acid was the most abundant unsaturated fatty acid. The unsaturated fatty acid of pork patty was increased in proportion to olive oil substitution ratio. Therefore, the olive oil gel substitution of low-fat pork patty results in a positive effect on the physicochemical qualities due to reduced cholesterol and saturated fatty acids.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.24 no.3
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• pp.96-104
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• 1998

It was possible to produce W/O/W one step multiple emulsion on the system which satisfied following conditions. 1. 1-5％ of hydrophilic liquid surfactant over HLB20 and lipophilic liquid surfactant which has HLB 3∼5 2. Non wax copolymers as oil thickener 3. More than 0.5％ of carbomer as aqueous thickener 4. The manufacturing process which neutralize the dispersed carbomer (2.0％ in water), after emulsifying. For the selective addition into inner and outer aqueous phase, we melted the glucose in water before emulsifying. Using an Anthrone analysis method, we analyzed the encapsulation yield of glucose in inner water phase. It was possible to raise the water encapsulation yield of the multiple emulsion through the following conditions. 1. Using of anionic hydrophilic surfactant(HLB 40) and lipophilic surfactant (HLB 3∼5) 2. Controlling the ratio of hydrophilic surfactant and lipophilic surfactant 3. Strengthening interface with increase of non wax oil thickener. When the separated adding process of glucose was adopted, approximately 85％ of glucose was added selectively within inner aqueous phase.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.443-450
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• 2019

We studied to find the optimal manufacturing conditions of coffee grounds sludge RDF with oil drying method. We expanded the lab scale to pilot scale to compare the efficiency of the oil-drying equipment and The selection of the ratio of coffee grounds and oil, the setting temperature, and the temperature change and water content with time were measured. In order to analyze the characteristics of the research results, characteristics of solid fuels produced(Coffee grounds of oil-dried) by calorimeter, TGA, combustion equipment, and combustion gas measuring instrument were analyzed. As a result, the ratio of oil to coffee grounds was 4: 1, and when the setting temperature was set to $300^{\circ}C$, the water content reached 10wt.% or less within 20 minutes. ln addition, it showed high calorific value of 6,273kcal/kg. However, coffee grounds had a similar composition to wood and showed high luminance and produced a lot of CO in combustion gas. As a result, it is considered to be unsuitable for thermoelectric power plant and camping fuel, but the initial ignition speed is high and the heat generation is high, so it is considered that it can replace the fuels for current use.

• KSBB Journal
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• v.23 no.6
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• pp.509-512
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• 2008

The hydrolysis reaction of soybean oil was conducted experimentally by various source enzymes. The analytical result of hydrolysate of soybean oil showed that the compositions were linoleic acid, olic acid, palmitic acid, and stearic acid in order. The enzymes CR-E and CC-E from Candida rufosa and Candida cylindracea had two hold or more hydrolysis conversions than those of Lipase 16, Novozyme 871, and Lipolase-100L under the same conditions. Therefore CR-E and CC-E were selected for further experiments. These two enzymes had similar ranges of optimun conditions as follows: pH 3-6, $35-45^{\circ}C$, and water to soybean oil ratio of 3.3 or above. They finally got conversions 95% above.

• Applied Chemistry for Engineering
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• v.5 no.2
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• pp.274-284
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• 1994

Phase Inversion Temperature (PIT) measurements showed that the addition of polar components such as oleyl alcohol and oleic acid to the system comprising n-dodecylpentaoxyethylene monoether ($C_{12}E_5$), nonpolar oil (n-hexadecane) and water produced large reductions in the PIT. The PIT was lowered as the additive-to-surfactant ratio in the surfactant films in the microemulsion phase was increased. Another dramatic effect of additive was the manner in which it affects the volume of the microemulsion phase at the PIT of the oil and water solubilization characteristics. Microemulsion phase volume was increased rapidly with decreasing PIT, i.e., with increasing amounts of additive in the system. Also with a decrease in PIT, the solubilization parameters of both oil and water in the microemulsion phase were strikingly increased. Even though soil removal data were not available for the conditions where our results obtained, PIT measurement seems a useful starting point for estimating conditions when middle-phase microemulsion formation and its associated high solubilization of oil can be expected.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.121-125
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• 2002

Rhodococcus rhodochrous IGTSS (ATCC 5396S) can break organo sulfur compounds such as dibenzothiophene. Since the environment for biodesulfurization process is invariably hydrophobic, parameters in hydrophobic systems should be examined. For the model oil, hexadecane-containing 5.43mM dibenzothiophene, the volumetric desulfurization rate was decreased with the oil-to-aqueous phase ratio up to 50%. The rate declined sharply after 48h because the cell activity, which is refreshed by medium exchange, was lost. To supply the exhausted nutrients, medium exchange was performed. At 30% oil phase, most of DBT was removed by medium exchange on 48h, and the rate was 2.03mg $DBT_{removed}/L_{dispersion}-hr.$ At 50% oil phase, medium exchange on 60h was performed and the rate was 1.79mg $DBT_{removed}/L_{dispersion}-hr.$ The 300mL flask system was scaled up to a 5-L bioreactor system. On 60 h, a medium exchange was performed and the rate was 5.28mg $DBT_{removed}/L_{dispersion}-hr.$ and all of DBT was removed. It means that we can use the biodesulfurization process even 10 the high oil-to-water phase by some appropriate methods such as controlled feeding of key nutrients and the dilution or removal of some toxic metabolites by continuous reactor.

• Journal of the Korean Applied Science and Technology
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• v.7 no.1
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• pp.63-70
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• 1990

Influence of mixing ratio of blending oil (rice bran oil : RBD palm olein = 1 : 1, 1 : 4 mixture: w/w) and natural tocopherol, citric acid, and sodium polyphosphate on enhancement of oxidation stability of blending oil under the condition of tap water infulx(1 ml/min/200g oil) were compared by AOM test after heating these system at l80$^{\circ}C$. In addition, the effects of tocopherol, and synergist on oxidition stability were also tested with potato chips fried with blending oil(1 : 4 mixture). The result obtained were as followes; 1. The test of RBD palm olein addition of 50% and 80% against rice bran oil on oxidation stability showed that the higher the palm olein contents in blending oil, the higher the oxidation stability. 2. The test of oxidation stability, adding l00ppm, 200ppm and 400ppm of natural tocopherol in two different types of blending oils, A(1 : 1 mixture) and B(1 : 4 mixture), disclosed that blending oil B was more positively effective, and this trend was superior at 200ppm level particularly, Furthermore, oxidation stability was enhanced remarkably upon addition of 100ppm of natural tocopherol, and 50ppm of citric acid together with 50ppm, 100ppm and 200ppm of sodium polyphosphate in general. Especially, 200ppm of sodium polyphosphate addition induced the most synergetic effect on oxidation stability showing as much as 3 times compare to control. 3. The results of oxidation stability obtained by peroxide value on potato chips fried with blending oil (1:4 mixture} added tocopherol, citric acid and sodium polyphosphate and preserved at $60^{\circ}C$ revealed that addition of tocopherol and 50ppm of citric acid together with 200ppm of sodium polyphosphate treatment was the most synergistic coinciding with AOM test results.