• Bulletin of Korea Environmental Preservation Association
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• v.6 no.1
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• pp.46-48
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• 1984

• Bulletin of Korea Environmental Preservation Association
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• v.6 no.4
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• pp.32-35
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• 1984

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.4
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• pp.319-326
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• 2011

In order to investigate the potential of Nigella sativa (N. sativa) oil as an active ingredient for whitening cosmetics, we prepared N. sativa oil. We measured its inhibitory effects on mushroom tyrosinase activity, cellular tyrosinase activity, and melanin synthesis inhibitory activity in B16 melanoma cells. N. sativa oil and its components showed inhibitory activity against mushroom tyrosinase and melanin synthesis. In a melanin synthesis inhibition assay using mouse B16-F10 melanoma cell, it reduced melanin production up to 86 % at a concentration of 10 mg/mL without cytotoxicity. In the study on the melanogenic protein expressions by using RT-PCR and Western blot, N. sativa oil and its components inhibited expression of tyrosinase protein, which is a well-known key protein on melanogenesis, and tyrosinase expression was gradually decreased in a dose-dependent manner. Therefore, this result suggests that N. sativa oil could be used as an active ingredient for whitening cosmetics.

• Korean Chemical Engineering Research
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• v.45 no.3
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• pp.219-225
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• 2007

The equilibrium solubilization capacity of pure hydrocarbon oils by 2.5 wt% $C_{12}E_8$ nonionic surfactant solution was measured at $30^{\circ}C$ by gas chromatography (GC) analysis. Experimental results indicated that the molar solubilization ratio (MSR) for pure alkanes was found to decrease almost linearly with the alkane carbon number (ACN) of the hydrocarbon oil. For the binary mixture systems of the hydrocarbon oils both selective and nonselective solubilization behaviors were observed depending on the difference in carbon number of the two hydrocarbon oils. Equilibrium solubilization tests for the two n-octane/n-nonane and n-nonane/n-decane mixture systems in $C_{12}E_8$ surfactant solutions suggest slightly selective solubilization in favor of n-octane, but the small difference in solubilization rates between two hydrocarbon oils does not allow ruling out non-selective solubilization for these particular systems. This is certainly not the case for the n-octane/n-decane mixture, for which selective solubilization was conclusively demonstrated by GC analysis data.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.25 no.1
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• pp.137-155
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• 1999

The o/w emulsions were prepared by lysolecithin as a biosurfactantsto to emulsify oils with squalane(SQ), liquid paraffin(LP), octylpalmitate(OP), octylstearate(OS), alkyl benzoate(AB), isostearyl benzoate(ISB). The droplets size and shape of o/w emulsions were investigated by laser light scattering, With dynamic light scattering hydrodynamic radius(Rh) of emulsion droplets was varied from 150m to 250m and critical concentration of oil In which the hydrodynamic radius(Rh) of emulsion droplets decreased and increased was found in the point of 0.5wt% oil concentration, and it was found increasing the polarity of oil deccreased the droplets, the droplets size of SQ(polar oil) were lower than SQ(nonpolar oil) With static light scattering radius of gyration(R$_{g}$) of emulusion droplets was to be calculated. From measurements of the ratio of R$_{g}$R$_{h}$ it was found that the shape of droplet of ISB, AB(polar oils) were sphere, for OP, OS(apolar oil) were oblate, for LP, SQ(nonpolar oil) were rod. The viscosity of emulsion in the form of rod was higher than that of emulsion in the form of sphere.e.e.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.9
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• pp.791-801
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• 2000

An experimental study was conducted to analyze the effects of oil on refrigerant flow through adiabatic capillary tubes, and to develop a model for mass flow rates of refrigerant/oil mixture at various capillary tubes and flow conditions. Mass flow rates and the profiles of the pressures and temperatures along the capillary tubes was obtained with the oil concentration of R-22/SUNISO 4GS oil mixture at various test conditions. The flow trends as a function of geometry and flow conditions for pure refrigerant and refrigerant/oil mixture were similar in adiabatic capillary tubes. Mass flow rate of the refrigerant/oil mixture was less than that of pure refrigerant at the same test conditions.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.5
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• pp.81-88
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• 1999

In order to understand the relationship between the phase angle of piston ring and oil consumption was measured by analyzing $CO_2$concentration in exhaust gas. The use of hydrogen fuel not gasoline makes this possible because all of the carbon component in exhaust gas can be assumed to be produced from oil. As a result of experiment, it is known that the oil consumption varies periodically and a specific location of ring end gap was found at each peak of oil consumption. Therefore, it was found that the oil consumption was not constant even at the same operating conditions and this is because the relative locations of top and 2'nd ring end gap change arbitrarily.

• Korean Chemical Engineering Research
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• v.47 no.1
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• pp.24-30
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• 2009

In this study, solubilization experiments of n-decane, n-undecane and n-dodecane oil were performed by micellar solutions of polymeric nonionic surfactant Pluronic L64($EO_{13}PO_{30}EO_{13}$) at room temperature. A single spherical drop of hydrocarbon oil was injected into aqueous surfactant solution using an oil drop contacting technique and solubilization rate of hydrocarbon oil was measured by observing the size of oil drop with time. It was shown that solubilization rate decreased with the alkane carbon number(ACN) of the hydrocarbon oil. The solubilization rate was also found to be independent of initial oil dorp size and almost linearly proportional to the initial surfactant concentration. These results revealed that solubilization of n-decane, n-undecane and n-dodecane oils by L64 micellar solution is controlled by interface-controlled mechanism but not by diffusion-controlled mechanism. The equilibrium solubilization capacity(ESC) was measured by a turbidimeter and the result showed that EAC decreased with an increase in ACN but increased with both increases in surfactant concentration and solubilization rate. Dynamic interfacial tension measurements showed that interfacial tension and equilibrium time increased with an increase in ACN of hydrocarbon oil but decreased with an increase in surfactant concentration.

• Journal of Nutrition and Health
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• v.56 no.4
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• pp.361-376
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• 2023

Purpose: This study evaluates the potential protective effects of hemp (Cannabis sativa L.) seed oil supplementation in rats fed a high-cholesterol diet. Methods: Rats were fed a 1.25% cholesterol diet for 8 weeks, followed by oral administration of either of the two doses of hemp seed oil (HO) (0.5 mL/kg (HOL group) or 1 mL/kg (HOH group) body weight/day) or simvastatin at 10 mg/kg body weight/day. Oxidative stress, lipids, liver enzymes, and renal markers were measured in the serum. Western blot analysis was applied for evaluating the expressions of inflammatory makers. Results: Except for HDL-cholesterol, the altered levels of lipoproteins, aminotransferases, urea, and creatine kinases in hypercholesterolemic rats were significantly corrected by HO administration. Especially, compared to the HOH group, HOL treatment further reduced AST, ALT, creatinine, TC, and LDL-cholesterol levels. Moreover, both the atherogenic index and cardiac risk factor (CRF) in the HOL group were more restrained compared to the HOH group. Increased levels of p-AMPK coincided with the inhibition of SREBP-2 activation which subsequently suppressed the expression of HMGCR. Nuclear factor (NF)-κB activation coincided with the PI3K/Akt pathway activation and the increased phosphorylation of p38; these levels were significantly suppressed by HO treatment. In addition, HO treatment markedly reversed the changes in chemokines such as ICAM-1, VCAM-1, and MCP-1. Histological alterations induced by cholesterol overload in cardiac and hepatic tissues were ameliorated by HO supplementation. Conclusion: Taken together, our results indicate a low concentration of HO demonstrates improved dysfunctions caused by a high-cholesterol diet via inhibition of the PI3K/Akt/NF-κB signaling pathway.

• Analytical Science and Technology
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• v.33 no.6
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• pp.262-273
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• 2020

A fluorine content analysis method for krill oils, which is a representative oil formulation in foods, was developed in compliance with the Korea Food and Drug Ministry's "Guidelines for Validation of Testing Methods Related to Food". Using this method for krill oils, the presence of impurities was evaluated via combustion-ion chromatography (C-IC). A review of published technical data on fluorine in krill oils showed that while the traditional wet potentiometric method was typically used, it was not reliable. Moreover, there was no food testing/analysis laboratory in Korea to perform a fluorine test analysis on such an oil matrix. Therefore, we identified halogen (fluorine) tests, developed to national and international standards, and developed a test method suitable for krill oils by selecting a C-IC method that is sufficiently applicable to the oil matrix. Based on the characteristics of the oil matrix, the optimal test method was established through various experiments by reviewing the concerns related to loss and interference in the preparation and introduction of samples. The fluorine content test was carried out on 11 krill oil products that were purchased online. Most products (with the exception of only one) were found to contain less than the reporting limit obtained by the test method. Furthermore, after additional testing, a high fluorine content of approximately 2,000 ~ 3,000 mg/kg was detected on the krill surface, although the concentration varied depending on the area of the krill. A comparison with samples from two ISO/IEC 17025 testing laboratories confirmed that there was no significant difference in the statistical analysis results obtained by ANOVA among the three laboratories. A testing guide for fluorine content analysis was completed.