• International Journal of Air-Conditioning and Refrigeration
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• v.8 no.2
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• pp.80-88
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• 2000

In order to predict thermodynamic performance of refrigeration system, it is required to know the oil concentration of the refrigerant/oil mixture. The current method is to extract the working mixture and then to measure the oil weight. In this study, oil concentration is measured in si.tu way without any extraction of the working fluid. Based on the measurement, a working equation is presented as follows, C=a +b x t +c x $t^2$ +(d + e x t +f x $t^2$) x SG. C is oil concentration, t is temperature($^{\circ}C). SG Is specific gravity of mixture and a~f is coefficients The oil concentration ranges over 0~l2 wt% and the temperature ranges over 20~50$^{\circ}C. The specific gravity and temperature are measured using the on-line densimeter and thermometer. This working equation enables to predict the oil concentration without any extraction of the mixture. This equation can be applied for R-12/Naphthenic oil and R-134a/P0E oil liquid mixtures.

• Journal of Life Science
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• v.20 no.5
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• pp.662-669
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• 2010

Lipolytic enzyme-producing bacteria were isolated from edible oil mill effluents on tributyrin agar medium. The shake-flask-scale studies yielded a promising isolate and it was identified as Pseudomonas sp. An OME using various microbiological observations such as cultural, microscopic, and biochemical tests was undertaken and confirmed using PIBWIN bacterial identification software. Lipolytic enzyme production was screened with oils such as sunflower, caster, coconut, tributyrin, and olive. Amongst these, olive oil showed an increased lipase production 6.1 U/ml. In view of the highest lipolytic enzyme production with olive oil, further optimizations were carried out using olive oil as a carbon source. Lipolytic enzyme production was optimized by a conventional 'one variable at a time' approach and the significant factors were further analyzed statistically using response surface methodology (RSM). The effect of physical factors such as incubation time, temperature, initial medium pH, and nutritional factors such as concentration of olive oil and yeast extract were examined for lipase production. Lipolytic enzyme secretion was strongly affected by three variables (incubation time, concentration of yeast extract and olive oil). Therefore, the interaction of these three factors was further optimized using response surface methodology. The optimized conditions of lipase production using response surface methodology yielded a maximum of 9.62 U/ml with optimum conditions for incubation, yeast extract and olive oil concentrations were found to be 48 hr, 0.3 g. and 0.9 ml. respectively.

• KSBB Journal
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• v.14 no.6
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• pp.655-660
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• 1999

Supercritical fractional extraction of DHA and EPA from the mixture of fatty acids composing the fish oil was performed. The compositions, extracted quantities, and cumulative extracted quantities of fatty acids in the extract and the raffinate were investigated according to the fractional steps. The temperature and pressure for the miximum concentration of DHA and EPA in the extract or the raffinate were 60$^{\circ}C$ and 101 bar respectively among the extraction conditions considered in this study. In this case, the weight percent of EPA in the extract was 50% and that of DHA in the raffinate was 40%. These values were two times higher than those in fish oil. THe same temperature and pressure were used to extract DHA and EPA from the mixture of fatty acids whose the initial weight percent of DHA was 34%. The weight percent of DHA in the raffinate after the fourth fractionation was 7-%. And the remaining weight of DHA in the raffinate was 80% of DHA initially loaded in the extraction vessel.

• The Korea Journal of Herbology
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• v.32 no.1
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• pp.75-81
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• 2017

Objectives : The present study was designed to investigate effects of mixed extracts (9:1, v/v) of Hwangryunhaedoktang, Chamaecyparis obtusa essential oil. We evaluated the antimicrobial and antioxidant activity by manufacturing mixed extracts as the materials for functional medicinal herb cosmetics. Methods : We performed antimicrobial were tested microbes (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Candida albicans, Propionibacterium acnes) by disc diffusion method and measure clear zone. Antioxidant activities were measured by DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity. Results : Antimicrobial activities of mixed extracts against S. epidermideis, P. acnes, S. aureus, E. coli, and Candida. A were $10.9{\pm}3.0mm$, $16.9{\pm}2.0mm$, $9.2{\pm}2.0mm$, $10.3{\pm}1.0mm$, $11.8{\pm}3.0mm$ respectively. The Chamaecyparis obtusa essential oil had the highest antimicrobial activities against S. epidermideis, P. acnes, S. aureus, E. coli, and Candia. A and clear zone of microbes ware $16.7{\pm}3.0mm$, $28.8{\pm}0.2mm$, $15.9{\pm}2.0mm$, $11.5{\pm}1.0mm$, $16.3{\pm}3.0mm$. Hwangryunhaedoktang extract showed antimicrobial activity but only P. acnes and S. aureus The antioxidant activities of the mixed extracts were tested through the evaluation of DPPH radical scavenging activity. The 100 % mixed extracts were found to have 90 % DPPH radical scavenging activity. The mixed extracts was presented similar antioxidant activities compared with that of ascorbic acid. As a result, A mixture extract is expected to have antimicrobial effects and free radical scavenging activity was found. Conclusions : Accordingly, It can be concluded that mixed extracts has the potential to cosmetic material.

• Journal of Applied Biological Chemistry
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• v.59 no.2
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• pp.165-169
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• 2016

The quantitative analytical method for the bioactive substance, 3-cyano-4-methoxy-N-methyl-2-pyridone (ricinine) and an index compound, ricinoleic acid in castor plant (Ricinus communis) extract or oil was developed. For the determination of a pyridone alkaloid compound, ricinine, successive cartridge cleanup method combined with ultra-performance liquid chromatography was set up with $ENVI-Carb^{TM}$ (0.5 g) and $C_{18}$ SPE cartridges. Accuracy and precision were evaluated through fortification studies of one biopesticide (PE) at 10 and $100mg\;kg^{-1}$. Mean recoveries of ricinine were 98.7 and 96.0 % associated with less than 10 % RSD, respectively. For the determination of ricinoleic acid in castor extract and oil, saponification and methylation were optimized using gas chromatography-time of flight mass spectrometry. Recovery was more than 84.8 % associated with 6.2 % RSD after derivatization procedure. Both methodologies developed were applied to analyze real samples including three castor oil products and six commercially available biopesticides containing R. communis, collected at Korean market. The contents of ricinine and ricinoleic acid in most commercial biopesticides were less than the oil or extract contents indicated by label.

• Journal of the Korean Society of Food Culture
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• v.27 no.4
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• pp.407-413
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• 2012

In previous studies, we performed joint animal studies and clinical trials between Yonsei University and Oryza Oil & Fat Chemical Co. Ltd. We have shown that coffee bean extract has potent anti-obesity and hypotriglyceridemic activities as well as beneficial effects on body fat reduction.In this study, the effects of coffee bean extract (100 mg/capsule) on body fat reduction were evaluated in overweight/obese women (body mass index of 25~30 $kg/m^2$ or body fat > 30%) not diagnosed with any type of disease. Subjects were randomly assigned to a coffee bean extract group (n=10) or placebo group (n=10). We measured anthropometric parameters, abdominal fat distribution by computed tomography and blood components before and after the 8week intervention period. After supplementation, the coffee bean extract group showed body weight (p=0.08), body mass index (p=0.06), hip circumference (p<0.05), and upper waist circumference (p< 0.01). In addition, after 8 weeks, the coffee bean extract group showed a significant decrease in abdominal internal fat area compared to 0 weeks (0 weeks : $155.8cm^2$; 8 weeks : $145.9cm^2$, ${\Delta}$ change : $-9.9cm^2$, respectively). However, there were no significant differences in lipid profiles or serological measurements between the coffee bean extract group and placebo group. The results of our human study demonstrated that coffee bean extract supplementation for 8 weeks has beneficial effects on reducing abdominal internal fat area as well as hip and waist circumferences.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.647-652
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• 2018

Extracts from bay leaves, Chongbaek (Allium fistulosum L.), Hutgae (Hovenia dulcis Thunb.) fruit, and green tea, using Soju (Korean alcohol, $30^{\circ}$) as a solvent were analyzed for their antioxidative properties. The eels were evenly coated with the extract concentration equivalent to 2% of their total weight and dried for 15 hours at $35^{\circ}C$ using an air blower. The DPPH radical scavenging effect, acid value and peroxide value of semi-dried eel, and linoleic acid peroxidation of eel oil were investigated. The highest level of DPPH radical scavenging was found in green tea extracts, followed by Hutgae fruit extract and bay leaves extract (p<0.05). The acid value and peroxide value of Hutgae fruit extracts coated eels refrigerated for 21 days were the lowest followed by the green tea extract coated eels. During the 20 days reaction period, all four kinds of extracts analyzed were found to effectively decrease linoleic acid peroxidation. Among them, Hutgae fruit and green tea extracts decreased the peroxide content of eel oil steadily and for a longer period when compared to other extracts. In conclusion, pre-application of Hutgae fruit and green tea extracts on eels before drying was found to be effective in delaying peroxidation in eels during the drying process and refrigeration.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.343-349
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• 2013

Environment-friendly agro-materials tend to be preferred to chemical insecticides recently. For this reason, many studies are conducted to develop environment-friendly insecticides containing natural materials. The purpose of this study was to assess ecotoxicity for pepper extract and cassia oil (11.5+46%, A), pepper extract and cassia oil (23+34%, B), and pepper extract and lavender oil (40+10%, C). They are expected to prevent from pests especially diamondback moth, and can be used for agro-materials. Their formulation was emusifiable concentration (EC). Target species used to assess acute toxicity were aquatic invertebrate (Daphina magna), fish (Cyprinus carpio), honeybee (Apis mellifera L.) and earthworm (Eisenia fetida). The $EC_{50}$ value of A, B, and C to aquatic invertebrate were 0.46, 1.9, 0.25 mg $L^{-1}$ respectively and these values were moderately toxic according to standard of USEPA. In case of acute toxicity test to fish, the $LC_{50}$ of A, B, and C were 1.9, 2.9, 3.8 mg $L^{-1}$ respectively. A was category II in acute toxicity of fish and not acceptable to evaluation criteria of environment-friendly agro-materials. B and C were category III and acceptable. Acute contact and oral toxicity test to honeybee were conducted and the $LD_{50}$ of A, B, and C were > 100 ${\mu}g$ a.i. $bee^{-1}$ in both of tests. It indicated they were low toxic to honeybee. In case of acute toxicity test to earthworm, $LC_{50}$ of A, B, and C were 695, 988, and 564 mg $kg^{-1}$. In conclusion, pepper extract+cassia oil 57% EC and pepper extract+lavender oil 50% EC were expected to be used for environment-friendly insecticide materials with low risk against ecosystem and contribute to developing environment-friendly agro-materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1767-1775
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• 2013

The purpose of this study is to investigate the total polyphenol and antioxidant activities of radish buds (Raphanus sativus L.) based on sprouting periods and extraction solvents in order to present basic data that are needed for using the radish buds as functional food material. The antioxidant activities were assessed by using various antioxidant models (DPPH, TBARS, Rancimat method, POV). The total polyphenol contents according to the extraction solvents were 84.11 and 296.51 mg/g, and the ethanol extract on day 4 of showed the highest value as 296.51 mg/g. As for DPPH radical-scavenging activity, on the day 4 of sprouting, water extracts indicated the highest scavenging activity by 86.67%, and the acetone extracts indicated a rather low scavenging activity as 77.23%. As for TBARS measurement of the radish bud extracts on day 4 of sprouting the extract of 70% ethanol was highest (71.48%). On day 8 of sprouting the TBARS value was increased and the methanol extract was highest (78.99%). As for the oxidative induction period on day 4 of sprouting in Rancimat measurement, the methanol extract was highest (6.07 hours) on day 4 and the antioxidant index was 1.16. On day 12 of sprouting, the general oxidative induction period tended to be reduced to 5.25 to 5.91 hours. In the peroxide value measurement on day 4 of sprouting and beginning of the storage, the extracts showed no difference between 3.02 meq/kg oil and 4.12 meq/kg oil, and on the day 60 of storage, the water extract (43.83 meq/kg oil) and the methanol extract (45.42 meq/kg oil) were lowest with higher antioxidant effect. In conclusion, the radish bud extract with higher total polyphenol contents and antioxidant activities may serve as functional material for food additives, such as natural antioxidants and food preserving agents.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1880-1886
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• 2007

This study was conducted to examine the effects of different soy-oil and soy-lecithin levels on growth performance, nutrient utilization and serum parameters in broiler chickens. Two hundred and forty 1-day-old Arbor Acres chicks were randomly divided into 4 groups and treated as follows: basal diet with 2% soy-oil (SO); soy-oil and soy-lecithin mixture in proportion of 75/25 (SOL1), 50/50 (SOL2) and 2% lecithin (SL). At the end of the trial (42 d), birds in SOL1 group grew faster (p<0.05) and had better feed conversion efficiency (p<0.05) than other groups while SL group had the lowest performance (p<0.05). The utilization of ether extract was improved in SOL1 group (p<0.05) but apparent metabolizable energy (AME) and utilization of other nutrients decreased in SOL2 and SL group from 19 to 21 d. No significant effects were observed in apparent metabolizable energy, dry matter, crude protein and ether extract but the utilization of calcium and phosphorus was significantly improved in SL group (p<0.05) during 39 to 42 d. The birds fed with lecithin had lower serum total cholesterol and triglyceride than the control group (SO). Broilers fed with 2% lecithin (SL) had the highest insulin level (p<0.05). The results implied that soy-lecithin and soy-oil in a proportion of 25:75 had the highest growth performance and that soy-lecithin had cholesterol lowering capacity.