• Korean journal of food and cookery science
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• v.15 no.1
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• pp.55-60
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• 1999

Free phenolic acid, soluble phenolic acid ester and insoluble bound phenolic acid were extracted from defatted perilla flour. Their antioxidative effects were compared with those of BHA, AE and TBHQ for soybean oils by measuring acid and peroxide values at 60$^{\circ}C$ for 25 days. The patterns of these extracts were compared by using gas chromatography. Free phenolic acid and soluble phenolic acid ester extracts showed a higher antioxidative effects than BHA and AP. Among phenolic extracts, free phenolic acid showed the most effective antioxidant activity in soybean oil. Six types of free phenolic acid, 3 types of soluble phenolic acid ester, and 2 types of insoluble phenolic acid were found in the extract.

• YAKHAK HOEJI
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• v.39 no.5
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• pp.487-494
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• 1995

Solid lipid microspheres (SLMs) were prepared using various lipids and solidifying agents, in order to enhance the gastrointestinal absorption of Cyclosporine A (Cs A) which is a practically water-insoluble drug with low systemic bioavailability. Egg lecithin and HCO-60 (polyoxyethylated 60 mol, hydrogenated castor oil) were used as lipids. Stearic acid and stearyl alcohol were used as solidifying agents. Emulsion concentrates containing Cs A were prepared by mixing the melted lipid and solidifying agent with water, employing bile salts as a cosurfactant. SLMs were obtained by dispersing the warm emulsion concentrate in cold distilled water under mechanical stirring, followed by freeze drying. Physical characteristics of each SLM were investigated by particle size analysis, optical microscopy and scanning electron microscopy. Mean particle size of SLMs was in the range of 30 to 40.mu.m. The SLMs were in good appearance with spherical shape before freeze drying, but were deformed partially after freeze drying. Drug loading efficiencies of SLMs were observed as high as 80 to 90% in average. The systemic bioavailability of Cs A from different SLM formula was investigated in rats following oral administration. Cs A in whole blood was extracted and assayed by HPLC. SLMs revealed the higher bioavailabilities than the standard formula based on the marketed product. SLMs might have several advantages over standard formula for enhanced gastrointestinal absorption, controlled release properties, high loading capacity of the water-insoluble drug, and feasibility of solid dosage forms with better stability in storage.

• Journal of Dairy Science and Biotechnology
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• v.23 no.2
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• pp.115-123
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• 2005

Microcapsules consisting of natural, biodegradable polymers for controlled and/or sustained core release applications are needed. Physicochemical properties of whey proteins suggest that they may be suitable wall materials in developing such microcapsules. The objectives of the research were to develop water-insoluble, whey protein-based microcapsules containing a model water-soluble drug using a chemical cross-linking agent, glutaraldehyde, and to investigate core release from these capsules at simulated physiological conditions. A model water soluble drug, theophylline, was suspended in whey protein isolate (WPI) solution. The suspension was dispersed in a mixture of dichloromethane and hexane containing 1% biomedical polyurethane. Protein matrices were cross-linked with 7.5-30 ml of glutaraldehyde-saturated toluene (GAST) for 1-3 hr. Microcapsules were harvested, washed, dried and analyzed for core retention, microstructure, and core release in enzyme-free simulated gastric fluid (SGF) and simulated intestinal fluid(SIF) at $37^{\circ}C$. A method consisting of double emulsification and heat gelation was also developed to prepare water-insoluble, whey protein-based microcapsules containing anhydrous milkfat (AMF) as a model apolar core. AMF was emulsified into WPI solution (15${\sim}$30%, pH 4.5-7.2) at a proportion of 25${\sim}$50%(w/w, on dry basis). The oil-in-water emulsion was then added and dispersed into corn oil ($50^{\circ}C$) to form an O/W/O double emulsion and then heated at $85^{\circ}C$ for 20 min for gelation of whey protein wall matrix. Effects of emulsion composition and pH on core retention, microstructure, and water-solubility of microcapsules were determined. Overall results suggest that whey proteins can be used in developing microcapsules for controlled and sustained core release applications.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.134-134
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• 2001

Cutting oils are complex mixtures of hydrocarbons, comprising of certain fractions of mineral oil, which are being frequently used as lubricating and heat transferring agents in various machine and tool industries. We investigated an acute and 2 weeks repeated irritation studies of two cutting oils (Cimperial 1010 as water-soluble cutting oil, and MSN 120 as insoluble cutting oil) using guinea pigs.(omitted)

• The Korean Journal of Food And Nutrition
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• v.9 no.2
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• pp.137-142
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• 1996

To develop antioxidant substances in plant, phenolic compounds in Bangah (Igodon japonicus, Hara) and antioxidative effects of cell extracts were investigated. Defatted samples of Bangah were extracted with acetone/methanol and the extracts were fractionated Into the free and bound types of phenolics. The equal amounts of fractions were dissolved In soybean oil and autoxidized at 45$^{\circ}C$ for 25 days. Peroxide value and TBA values were determined every 5 days during oxidation. Changes of peroxide and TBA values showed antioxidant effects, which were lower than control during the oxidation periods. The effects of cell extracts were evaluated as high as BHT, 0.02 ppm. The antioxidative effect of insoluble-bound phenolic extract was higher than that of free. The contents of phenolic compounds in insoluble-bound fraction were also higher than free fraction.

• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.402-406
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• 2013

In this study, a pitch for melt-electrospinning was prepared from naphtha cracking bottom (NCB) oil by the modification with heat treatment. The softening point and property of the modified pitch was influenced by modification conditions such as nitrogen flow rate, heat treatment temperature, and reaction time. Among these, the heat treatment temperature had a very strong influence on the distribution of molecular weight and softening point of the pitch. The C/H mole ratio and average molecular weight increased with increasing the heat treatment temperature due the decomposition and cyclization reaction of surface-functional groups. In addition, the values of benzene insoluble and quinoline insoluble also tends to decrease, and the width of molecular weight distribution seems to get more narrow. The carbon fiber with a diameter of $4.8{\mu}m$ was prepared from a modified pitch at the softening point of $155^{\circ}C$ by melt-electrospinning. It is believed that the melt-electro spinning method is much more convenient to get the thinner fiber than the conventional melt spinning method.

• Tribology and Lubricants
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• v.32 no.3
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• pp.82-87
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• 2016

We performed an experimental research on lubricant oil in dual fuel medium-speed engines. It is important to select the appropriate lubricant oil because it could significantly affect engine lifetime and performance. We generally recommend the selection of the lubricant oil according to the fuel grades as contents in the project guide. However, it is a considerable challenge for shipyards to implement this concept because of the lack of space to install the complicated lubricating oil system for dual fuel engines. Therefore, we determine the adaptability of one-common lubricant oil for HiMSEN dual fuel engine through this experimental research. To check abnormality in gas mode operation and durability of engine components when a lubricating oil with high BN (base number) is used, overhaul inspections and lubricant oil analysis are carried out two times, and four times, respectively, during an operation of approximately 300 h. We investigated the variations in kinematic viscosity, base number, element quantity, pentane insoluble and sulfated ash in lubricant oil analysis. Moreover, we also investigated whether the deposit formation or wear occurred in various bearings, injectors, exhaust valves, intake valves, piston rings and so on through the overhaul inspections. There are no problems in the lubricant analysis and the overhaul inspections. Through the experimental research, we confirm that one-common lubricant oil should be selected according to the higher sulfur content of fuel oil in dual fuel engines.

• Current Research on Agriculture and Life Sciences
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• v.10
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• pp.11-17
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• 1992

In this study, antioxidative effectiveness of BHA, BHT at 0.02%(w/w) was compared with those of separated free phenolic acid, ester form and insoluble bound phenolic acid which were extracted from 50 g of Terminalia chebula Retz by MeOH/aceton solvents. Antioxidative effectiveness was measured by peroxide values and TBA values for 7 days, storaging respective substrates and contrast tube at $45{\pm}1^{\circ}C$ for 35days. Laboratory tubes was added by BHA, BHT, separated free, soluble and insoluble phenolic acid extracts and peroxide value of contrast tube after 21 day storage were 60, 30, 14, 11, 100. On the other hand, at the same conditions, TBA values of each antioxidants were 0.150, 0.108, 0.105, 0.073, 0.078, 0.185. This results remarkably appeared antioxidative effectiveness in meal soybean oil substrates. Phenolic acid separated and identificated were p-coumaric acid, Ferulic acid, Phloroglucinol, Pyrogallol, Vanillic acid and Caffeic acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.17-22
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• 1992

Water extract, and free-, ester- and insoluble phenolic acids were extracted from wormwoods. The extracts were then dissolved in equal amounts of an edible soybean oil, and the resulting substrates, portion of the soybean oil (control), 0.02% BHA and 0.02% BHT were stored in incubator at $45^{\circ}C{\pm}1.0^{\circ}C$ for 32days. Peroxide values (POV) and thiobarbituric acid (TBA) values of control and the substrates were determined during th9 storage period. The POV of control, BHA, BHT and six substrates which were contained water extracts 0.5%, 1% and 1.5%, and free-, ester- and insoluble phenolic acids after 24days of storage were 77, 43, 17, 38, 26, 34, 45, 28 and 16m mole/kg oil respectively, The TBA values after 32days of storage were 0.278, 0.170, 0.070, 0.200, 0.178, 0.235, 0.167, 0.136, 0.062, respectively, It was found that the antioxidant activity in water extracts was highest in water 1 (the substrates containing water extracts 1%). It was also found that antioxidant activities in the phenolic acids were decreased in the following order ; insoluble phenolic acids>ester form>free phenolic acids. The phenolic acids separated and tentatively identified by Gas chromatography were catechol, vanillin, umbelliferone, p-coumaric acid, ferulic acid caffeic acid, protocatechuic acid, p-hydroxy benzoic acid and syringic acid.

• YAKHAK HOEJI
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• v.10 no.2_3
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• pp.29-32
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• 1966

The seed of Torreya nucifera, which has been widely used as folk medicine in the treatment of tapeworm infestation, was pharmacologically examined to isolate the biologically active component. It was found that the water insoluble part of the methanol extract of the seed, which was previously pressed to remove inactive oil fraction, showed remarkable anthelmintic effects on the rat infected with Hymenolepis diminuta (rat tapeworm).