• Journal of Korean society of Dental Hygiene
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• v.15 no.2
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• pp.325-332
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• 2015

Objectives: The purpose of this study was to investigate tooth whitening maintenance efficacy of several dentifrices containing effective ingredients for tooth whitening. Methods: Hydroxyapatite specimens(HAPs) staining was done by using modified Stookey's methods. HAPs were treated with 2.9% hydrogen peroxide containing strip for whitening, and were shaken with several dentifrice slurry(dentifrice 1 : artificial saliva 2) for 30 minutes. The HAPs were finally dipped in staining solution for an hour. Shaking and dipping were repeated 4 times and lightness values were measured by colorimeter at each step. In clinical test, test 4 dentifrice and control dentifrice were evaluated by 21 subjects for 2 months after receiving institutional review board(IRB) approval. Organoleptic(vita shade guide) and instrumental(SHADEEYE-NCC) evaluation were performed for whiteness change of teeth. Statistical analysis was performed using repeated measures ANOVA, Tukey's post hoc test and ${\chi}^2$-test(p<0.05). Results: All dentifrices showed statistical significance in comparison with control dentifrice containing sodium fluoride and test 4 dentifrice containing sodium pyrophosphate, sodium metaphosphate, candelilla wax, and sodium fluoride showed statistical significance in comparison with other dentifrices by inhibiting staining in vitro(p<0.05). In clinical test, test 4 dentifrice showed better effects than control dentifrice in organoleptic and instrumental evaluation in tooth whitening maintenance efficacy(p<0.05). The awareness toward tooth whitening maintenance efficacy for 2 months use showed that test 4 dentifrice was much better than control dentifrice, but did not show statistically significant(p>0.05). Conclusions: Dentifrice containing sodium pyrophosphate, sodium metaphosphate, candelilla wax and sodium fluoride was more effective in keeping teeth white.

• The Korean Journal of Food And Nutrition
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• v.35 no.6
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• pp.417-425
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• 2022

The purpose of this study was to investigate the antioxidant activities, quality characteristics, and storage stability of perilla oil mayonnaise (PM) with different levels of onion powder (OP) from 0 to 3%. As the amount of OP increased, the L, a, and b values increased, but pH decreased (p<0.05). The addition of OP raised viscosity (p<0.05). The addition of OP to PM proportionally increased the total phenolic content, and antioxidant activities as measured by DPPH and ABTS radical scavenging activity, and FRAP assay. When compared to PM without OP, PM that contained OP had a peroxide value that was almost 1.94 times lower. The emulsion stability was between 97.62 to 94.92% in the PM without OP and PM with OP groups was 99.60% for 12 weeks. This study showed that the inclusion of OP in PM has the potential to inprove its quality, antioxidant activities, and storage stability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.3
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• pp.224-231
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• 2012

We investigated the effects of various washing methods on the quality of semi-dried Pacific saury Cololabis saira, known in Korea as Guamegi. We immersed samples for 5 min in seawater, tap water, chlorinated water (100 mg/kg), ammonia water (100 mg/kg), citric acid (0.1 M), butylated hydroxyanisole (BHA, 0.2 g/kg), or sesame oil (5 g/100 g), and then dried them in the sun for 3 days. The moisture and crude lipid contents after drying were 26.62-32.49 g/100 g and 26.40-33.01 g/100 g, respectively. The moisture content significantly decreased while the crude lipid content increased during drying. The different washing methods did not have a significant effect on the acidity, peroxide values, or levels of thiobarbituric acid or biogenic amine in Guamegi. The lightness of Guamegi during drying significantly decreased, but this decrease was not significantly different among washing methods. The degree of acceptance in a sensory evaluation was higher for Guamegi treated with sesame oil. Our results suggest that these washing methods should not be used to inhibit lipid oxidation, biogenic amine formation, or color changes in semi-dried Pacific saury, because effective components are extracted by the lipids during drying.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5229-5232
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• 2012

The incidence of malignant melanoma increases with age. One significiant effect of aging processes is an accumulation of oxidative damage in the genetical material. In this study, the relationship between malignant melanoma and damage in chromosomes and proliferative effectiveness of human peripheral lymphocytes were investigated by the micronucleus (MN) technique. A total of 15 malignant melanoma patients and appropriately matching 15 healthy controls were involved in the study. MN frequencies and proliferative indexes (PI) after non toxic levels of hydrogen peroxide treatment were also measured to determine damaging effect of oxidative stress in genome in addition to measuring the spontenous levels of micronuclei and PI. The patient group had a significantly higher rate of spontaneous MN than the control group (p<0.01). After treatment with $H_2O_2$, MN frequencies in the patient group was significantly decreased (p<0.01) although there was no difference between the treated and untreated results of control group (p=0.29). There was also difference (p<0.01) between the MN frequencies of the patient and the control group either in the spontaneous levels or in the $H_2O_2$ treated groups. The same significant difference persisted when the PI values were compared between patient and control groups. Increase in the MN frequency in patients could mean the alterations in the chromosomal structure which may lead to the chromosome instability and therefore genetic susceptibility to cancer. This increased number of micronuclei can also be used for cytological marker in identifying high risk cases for malignant melanoma.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.48 no.5
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• pp.614-620
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• 2015

The objective of this study was to investigate sensory and lipid characterizations of boiled-dried Pacific herring Clupea pallasii (PH) as a substitute for boiled-dried anchovies (A). The crude lipid content of commercial boiled-dried PH ranged from 1.3 to 5.1%, which was similar to that of commercial boiled-dried A (2.2-5.1%). The peroxide values (POVs) of commercial boiled-dried PH ranged from 20.5 to 129.1 meq/kg. The POVs of commercial boiled-dried PH suggest that boiled-dried PA of high quality should be controlled by a POV standard similar to that of boiled-dried A. The trichloroacetic acid soluble-nitrogen (TCA soluble-N) content of commercial boiled-dried PH ranged from 495.7 to 998.6 mg/100 g, which was high compared to that of commercial boiled-dried A (372.6-690.0 mg/100 g). Volatile basic nitrogen (VBN) content of commercial boiled-dried PH ranged from 8.4 to 28.1 mg/100 g, which was low compared to that of commercial boiled-dried A (16.8-33.0 mg/100 g). Results from the lipid, POV, TCA-soluble-N, and VBN content analyses suggest that boiled-dried PH could be used as a substitute for boiled-dried A.

• Korean Journal of Pharmacognosy
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• v.37 no.3
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• pp.190-195
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• 2006

Obesity is associated with a number of pathological disorders such as non-insulin-dependent diabetes, hypertension, hyperlipidemia, and cardiovascular diseases. Bangpoongtongsungsankamibang (BTSK) has been widely used in the oriental medicine for the treatment of several diseases associated with inflammatory abnormalities in cardiovascular and nervous system. The BTSK is the modified prescription of Bangpoongtongsungsankamibang in which sea tangle (Laminaria japonica) were added. This study was carried out to detemine the anti-obestic effects of BTSK. Pretreatment with the BTSK at daily dose of 100 or 200 mg/kg (p.o.) far 4 weeks reduced serum triglyceride, total cholesterol contents in rat induced by Poloxamer-407 or Triton WR-1339, respectively. Furthermore, post-treatment with BTSK far four weeks also inhibited body weight gain, adipose tissue mass and hyperlipidemia induced by the high fat diet for six weeks. The BTSK shifted serum total-, HDL- and LDL-cholesterol levels toward the values of normal group, suggesting that BTSK has hypolipldemlc effects. The rats fed BTSK reduced lipid peroxide and hydroxy radical in the rat blood and increased superoxide dismutase (SOD) activity compared to the control group. Taken together, these results superoxide that BTSK improve hyperlidemia and obesity via the upregulation of anti-oxidative mechanism.

• International Journal of Automotive Technology
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• v.7 no.1
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• pp.1-7
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• 2006

The ignition delay of a dual fuel system has been numerically investigated by adopting a constant volume chamber as a model problem simulating diesel engine relevant conditions. A detailed chemical kinetic mechanism, consisting of 28 species and 135 elementary reactions, of dimethyl ether (DME) with methane ($CH_{4}$) sub-mechanism has been used in conjunction with the multi-dimensional reactive flow KIVA-3V code to simulate the autoignition process. The start of ignition was defined as the moment when the maximum temperature in the combustion vessel reached to 1900 K with which a best agreement with existing experiment was achieved. Ignition delays of liquid DME injected into air at various high pressures and temperatures compared well with the existing experimental results in a combustion bomb. When a small quantity of liquid DME was injected into premixtures of $CH_{4}$/air, the ignition delay times of the dual fuel system are longer than that observed with DME only, especially at higher initial temperatures. The variation in the ignition delay between DME only and dual fuel case tend to be constant for lower initial temperatures. It was also found that the predicted values of the ignition delay in dual fuel operation are dependent on the concentration of the gaseous $CH_{4}$ in the chamber charge and less dependent on the injected mass of DME. Temperature and equivalence ratio contours of the combustion process showed that the ignition commonly starts in the boundary at which near stoichiometric mixtures could exists. Parametric studies are also conducted to show the effect of additive such as hydrogen peroxide in the ignition delay. Apart from accurate predictions of ignition delay, the coupling between multi-dimensional flow and multi-step chemistry is essential to reveal detailed features of the ignition process.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.4
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• pp.470-476
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• 2013

The property of deep frying oil is one of the important factors in fried food quality. The purpose of this study is to identify the quality of deep frying oil in continuous usages for 4 days by two types of fryers: traditional deep-fat fryer and modified oil-water fryer. After frying pork cutlets, the frying oil was kept not only for several physical analyses such as color, viscosity, and water content but also for the quality analyses of frying oil, such as free fatty acid, double bond changes and oxidative rancidity formation. The oil fried in a traditional deep-fat fryer was significantly increased in terms of physical values including moisture content, viscosity, and color, compared to those of the modified fryer, continuously for 4 days. The oil fried by a traditional deep-fat fryer exhibited a significant increase in its free fatty acid content compared to that fried by a modified oil-water fryer, while the iodine value was significantly decreased in the oil fried by a traditional deep-fat fryer when compared to control oil and oil fried by the modified oil-water fryer. In the peroxide value as an indicator of primary oxidation products, the oil fried by both fryers was significantly increased till the second day but decreased in value after the third day because of unstable hydroperoxide decomposition. The p-anicidine value is used as an indicator of secondary oxidation products, the oil fried in a traditional deep-fat fryer was significantly increased in value compared to that of a modified oil-water fryer.

• Journal of the Korean Chemical Society
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• v.26 no.6
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• pp.421-426
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• 1982

Free radical-initiated copolymerization of diethyl isopropenyl phosphate (DEIPA) with vinyl acetate (VAc) and acrylonitrile (AN) was studied. The monomer reactivity ratios for the monomer pairs, determined at $60^{\cric}C$ using benzoyl peroxide as an initiator, are: ${\gamma}_1$(VAc) = 1.56, ${\gamma}_2$(DEIPA) = 0.44: ${\gamma}_1$(AN) = 15.2, ${\gamma}_2$(DEIPA) = 0.031. The values of the Alfrey-Price constants, Q and e, for DEIPA were calculated to be 0.015 and 0.39, respectively, from the VAc system, and 0.014 and 0.34, respectively, from AN/DEIPA pair. These results indicate that ${\alpha}$-methyl substituent of vinyl phosphate monomer decreases the general reactivity in free radical copolymerization. The intrinsic viscosity and number-average molecular weight of copolymers decreased as their content of DEIPA units increased, indicating a high degree of chain transfer caused by DEIPA, as previously learned in DEVPA system.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1420-1425
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• 1998

Rice wines, Yakju-type, were brewed with typical raw materials plus powdered acorns, and storage qualities of the fermented wines were examined. Initial optical densities of the acorn added-rice wines were shown around 0.116 at 660 nm and then decreased to $0.06{\sim}0.075$ after 10 days storage at $4^{\circ}C$. Organic acid contents in the acorn added-rice wines were lower than that of the control: the contents were lactic, succinic, citric, malic, oxalic and fumaric acid in order; and gallic acid, a kind of tannic substances was 0.39 mg%. Peroxide values of the acorn added-rice wines were not markedly changed for 9 days, remaining as low as $2{\sim}3\;meq\;kg^{-1}$ lard of lard, but that of the control was increased to $265\;meq\;kg^{-1}$ lard. As the results of clarity, acidity and antioxidation, the acorn added-rice wines appeared to be preservable, owing to tannic substances extracted from acorn powder.