• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.201-208
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• 2020

This study examined the anti-obesity effect of krill oil (KO) by regulating adipokines in a high-fat diet (HFD)-induced obese mouse model. The mice were fed a 60 kcal% HFD for 16 weeks, and KO was then administered at an oral dose of 100, 200, and 500 mg/kg/day for four weeks before the end of the experiment. The administration of KO at concentrations of 200 and 500 mg/kg/day decreased body weight gain significantly compared with the HFD-fed control group. In addition, the HFD-fed control group showed the abnormal release of adipokines by an increase in leptin and decrease in adiponectin, compared to the normal diet-fed normal group. On the other hand, KO (500 mg/kg/day)-administered group attenuated the abnormal release of adipokines by the down-regulation of leptin and the up-regulation of adiponectin. Therefore, KO could be a promising therapeutic agent for obesity by the regulation of adipokines.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.717-725
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• 2016

This study was designed to examine the in vitro antioxidant, antimicrobial and anti-inflammation effects of essential oils of Erigeron annuus L. Flower. Erigeron annuus L. essential oils were obtained by solvent extraction. Antioxidative ability was evaluated by bioassays using ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid diammonium salt) radical scavenging effect and 2, 2-diphenyl-1-1-picrydrazyl (DPPH) free radical scavenging activity. Erigeron annuus L. essential oil exhibited free radical scavenging activity on ABTS and DPPH 98.6%, 48.3% respectively, at a concentration of $500{\mu}g/ml$. Antimicrobial activity of essential oils of Erigeron annuus L. were tested against Staphylococcus aureus (S. aureus), Propionibacterium acnes (P. acne) and Escherichia coli (E. coli) by paper disc method, MIC and MBC. Erigeron annuus L. essential oil showed excellent antibacterial activities against S. aureus with MIC and MBC values of 0.31 mg/mL. The clear zone, indicating antimicrobial activity against P. acnes, was 14 mm, MIC and MBC values 0.31 mg/mL, 0.63 mg/mL, respectively. For the anti-inflammatory activity in RAW 264.7 cell, the Erigeron annuus L. essential oils inhibited not only NO production but also the expression of pro-inflammatory cytokines such as, TNF-${\alpha}$, IL-6 in a dose-dependent manner. These results suggested that Erigeron annuus L. essential oils has considerable potential as a cosmetic ingredient with antioxidative, antimicrobial and anti-inflammation effects.

• Economic and Environmental Geology
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• v.47 no.3
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• pp.247-254
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• 2014

The compressibility of fracture in naturally fractured reservoir is larger than the compressibility of matrix in rock, although the compressibility of a typical rock is very small. The effective compressibility including the fracture compressibility should be considered to predict oil recovery correctly. It is hard to quantify changes of fracture aperture and pore volume in reservoir without the effective compressibility. In this study, oil recovery is analyzed by commercial simulator concerning the fracture compressibility based on fracture properties. We found that the effective compressibility affects oil recovery with change of polymer flooding factors such as polymer molar weight, concentration and injection rate. The estimated cumulative oil production is smaller with the effective compressibility than without it. Also, bottomhole pressure decreases rapidly without considering effective fracture compressibility.

• Journal of Life Science
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• v.22 no.10
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• pp.1344-1351
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• 2012

We studied the physical, chemical, biological, and antimicrobial effects of eight types of essential oils used in the cosmetics industry: lavender, tea tree, rosemary, juniper berry, Chamaecyparis obtusa, cypress, cedar wood, and pine. Lavender oil had a linalyl acetate (an ester chemical compound) content of 48% and radical scavenging activity of 22.36% at 5,000 ppm. Tea tree oil had radical scavenging activity of 43.94% at 5,000 ppm and antimicrobial activity against S. aureus, S. epidermidis, S. mutans, and C. albicans in each 6, 3.5, 6.5, and 5 mm, respectively. Chamaecyparis obtusa oil had the highest acidity (pH 2.64) compared with the other oils, and sesquiterpene compounds were found to have 19.20%. Cedar wood oil had the highest specific gravity and refractive index compared to the other oils and had a sesquiterpene content of 99.73%. The radical scavenging activity of cedar wood essential oil exceeded 39.68% at 5,000 ppm. The clear zone, indicating antimicrobial activity against P. acnes, P. ovale, and C. albicans, was 3.5, 6, and 6 mm, respectively, at a concentration of 1% cedar wood oil. Results showed that with a high sesquiterpene content, the antioxidant effect was generally, but not always, high, suggesting that this is determined according to composition of the compound rather than presence of each antioxidant. The results indicate that antimicrobial activity is determined by the existence of each antimicrobial ingredient rather than terpene composition.

• Journal of the Institute of Convergence Signal Processing
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• v.22 no.1
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• pp.14-19
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• 2021

This study has attempted to use ozone for the treatment of skin diseases as research results that ozonated olive oil has an excellent therapeutic effect on skin diseases are known. However, there is hardly any accurate data in Korea. Usually, animal tests related to cosmetics are not performed, but toxicity tests were conducted because they were absolutely necessary. In general, there are not many cases of measuring actual data through animal tests for the purpose of confirming the performance of cosmetics, but in the case of toxicity tests, it is recommended to accurately measure skin reactions, so this experiment was conducted. In this experiment, in order to evaluate the skin irritation of ozonated oil (high concentration) on the rabbit, the test substance was applied to the back of the rabbit for 24 hours, and then mortality, general symptoms and skin irritation were evaluated. Experimental Results As a result of evaluating the treatment site of the test substance after a certain period of time, no skin irritation was observed in all animals.

• Journal of Energy Engineering
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• v.18 no.3
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• pp.203-211
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• 2009

Vapor pressure of HFC-404a and polyol ester system were measured at 56 points from 263.15 to 323.15 K and from 0 to 90 mass %polyol ester. It was found that below 273.15 K, the effect of the polyol ester on the vapor pressure was negligible up to 30 mass % polyol ester. The vapor pressure of the system significantly decreased as the mass fraction of polyol ester increased over 50 percent. Raoult's model and Flory-Huggins model were tested for data reduction. Empirical vapor pressure equations were obtained in terms of temperature and mass fraction of polyol ester.

• Korean Chemical Engineering Research
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• v.43 no.4
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• pp.511-516
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• 2005

In this work, the crosslinked-chitosan microcapsules containing fragrant oil were prepared by oil-in-water-in-oil (O/W/O) multi-emulsion method. The effects of concentration of fragrant oil and stirring rates on the preparing of the microcapsules were investigated. The diameter and form of the microcapsules were observed by scanning electron microscope (SEM). As a result, the average particle size of microcapsules was decreased with increasing the stirring rate. The formation of chitosan microcapsules was comfirmed by FT-IR. The inclusion of fragrant oil into chitosan microcapsules was determined in the presence of specific peak of fragrant oil, i.e., $1,460cm^{-1}$, $2,960cm^{-1}$. Also, the release behavior or profile of fragrant oil from chitosan microcapsules was examined with UV/vis spectra. Released amounts of fragrant oil were increased with increasing as the content of fragrant oil and decreasing the pH.

• Applied Chemistry for Engineering
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• v.33 no.1
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• pp.44-49
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• 2022

Essential oil was separated from Dendropanax morbiferus (DM) by means of hot water extraction and supercritical extraction, respectively, and the separated essential oil was analyzed qualitatively and quantitatively, and the antioxidant effect of essential oil was investigated. In addition, yields of essential oil and Caryophyllene according to the drying and extraction methods for each part of DM were obtained and compared, respectively. The yield of essential oil was found to be high in the order of bark > leaves > twigs > limb. When the freeze-dried DM leaves were supercritically extracted, the yields of essential oil and Caryophyllene were 23.2 g/kg DM and 429.6 mg Caryophyllene/kg DM, respectively. The essential oil of DM showed an antioxidant effect even at a low concentration, and the concentration of the essential oil of SC₅₀, which means 50% of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, was about 0.34%.

• Journal of Convergence for Information Technology
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• v.12 no.2
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• pp.192-197
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• 2022

Although various studies have focused on the relationship between essential oils (EOs) and skin flora, there are only few comparative studies on the antibacterial properties of EOs and their efficacy against common microorganisms. In this study, we tested the antibacterial activity of 10 different EOs against Staphylococcus epidermidis(S. epidermidis) with oxacillin as control. Optical density was used to measure the activity of solutions containing the EOs and S. epidermidis at two different concentrations. Three EOs (palmarosa, lemongrass, and Mellissa True) had higher antibacterial activity than oxacillin, but their concentrations had negligible effect on antibacterial activity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.3
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• pp.384-390
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• 1999

A vibrating U-Tube decimeter has been evaluated as a sensor for measuring the concentration of oil in the liquid line of a refrigeration system. Calibration and performance tests were conducted under simulated liquid-line conditions for R-407C/POE oil and R-410A/POE oil mixtures in oil concentration from 0 to 15 weight percent. Test temperatures ranged from 20 to 5$0^{\circ}C$. As a result of test, oil concentration correlations are presented in terms of specific gravity at each constant temperature. These equations enable to predict the oil concentration without any extraction of the mixture, and can be applied for R-407C/POE oil and R-410A/POE oil mixtures.