• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.72-81
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• 2008

The effect of genistein on melanin synthesis was studied using in vitro and in vivo model. Genistein inhibited melanin synthesis in cultured melan-a cells dose dependently. Tyrosinase activity was decreased by genistein treatment in melan-a cells, but genistein did not inhibit tyrosinase directly. Genistein did not affect the expression of tyrosinase in melan-a cells. Genistein inhibited the activity of ${\alpha}$-glucosidase in virtro and the glycosylation of tyrosinase in melan-a cells. The resulting unsaturated glycosylation of tyrosinase makes it unstable and disturb correct transportation. To further clarify the effect of genistein on the melanogenesis, we established UVB-induced hyperpigmentation on the shaved backs of brown guinea pigs. The animals were exposed to UVB radiation once a week for three consecutive weeks. Genistein (1 and 2%) or vehicle alone as a control were then topically applied to the hyperpigmented areas daily. Genistein showed significant lightening effect on the UVB-induced hyperpigmentation in five weeks. Depigmenting effect was prominent in 2% genistein treatment with Fontana-Masson staining. In conclusion, genistein may be a useful agent for skin whitening.

• Journal of Astronomy and Space Sciences
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• v.10 no.2
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• pp.123-145
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• 1993

UBVRi photometry of Algol was carried out from December of 1988 to March of 1991 at Chungbuk National University Observatory and a total of 3465 observations in U, B, V, R, I were obtained. Three times of primary minimum light of JDH el 2447898.0938, JEH el 2448265.1205 and JDH el 2448288.0598, and two secondary minimum light of JDH el 2447808.1014 and JDH el 2448275.146 were determined from our observations. We analyzed simultaneously the UBVRI light curves of the Algol system with the Wilson-Devinney method for the determination of the photometric parameters. Indivisual masses for the 3 components of Algol are derived as $m_1$=3.36, $m_2$=0.76, $m_3$=1.6 in solar mass and radii as $R_1$=2.97, $R_2$=0.76 in solar radinus using i=$82.{\circ}47$, q=0.227, $r_1$=0.2102, $r_2$=0.2512 of our solution and some parameters of the spectroscopic solution of Hill et al. (1971). Our results is simiar to those reported by Kim (1989). The temperature of Algol C, $T_3$=8800 was obtained by means of fitting $l_1$, $l_2$, and $l_3$ of five colors to Planckian curve, and $R_3$=$1.6R_\odot$ is derived from its result. It is believed that its semidetached configuration of Algol A and B is the consequence of case B mass transfer. According to its location in a mass-radius diagram. Algol b may have evolved significantly in its Hburnning phase.

• Food Science and Preservation
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• v.13 no.3
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• pp.322-328
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• 2006

This study was designed to investigate the Quality of salted eggplants with mixed rice bran and salt during 7 days at $4^{\circ}\C$ for the quality improvement and arrangement of eggplants exported to Japan. It was carried out to analyze the changes of the color, organic acids, amino acids and minerals during salting. L and b values of eggplants were decreased, and a value of eggplants was increased during salting. Organic acids such as acetic, citric, lactic, malic, and succinic acids were analyzed from eggplants. The content of acetic and malic acid were decreased during salting, but citric and succinic acid contents were increased The major amino acids were alanine, glycine, valine and leucine. Total amino acid content of Chukyang was decreased but that of Shikibu was not changed during salting. The major free amino acid was $\gamma$-aminobutyric acid and contents of $\alpha$-aminoadipic acid and $\gamma$-aminobutyric acid were increased during salting. Sodium and potassium were major minerals of eggplants. Sodium, potassium and magnesium were increased during salting.

• Journal of dental hygiene science
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• v.10 no.2
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• pp.95-100
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• 2010

The purposes of this study were to examine the effect of different fluoridated bleaching solution on the changes in physical and chemical characteristics of tooth. Forty-eight bovine incisors were divided into four groups to receive bleaching treatments, over a 14days period, as follows: no treatment; 10% carbamide peroxide (CP) bleaching; 10% CP containing 0.05% fluoride; and 10% CP containing 0.1% fluoride. All the specimens were highly polished and discolored with commercial COCK.Color and enamel changes were determined with colorimeter, microhardness tester, scanning electron microscope, atomic force microscopy. All the collected data were analyzed with one-way ANOVA. After the bleaching, bleached groups showed the color change(E*). Microhardness of 10% CP group decreased after tooth bleaching. But microhardness of containing fluoride bleached groups increased after tooth bleaching. Enamel surface of 10% CP bleached group showed any apparent morphology and roughness changes compared to the enamel which was stored in distilled water only. These results demonstrated that Fluoridated 10% Carbamide Peroxide have appreciable bleaching effect on bovine teeth and were not adversely affects enamel. Supporting influence of fluoride-containing bleaching solution on remineralization could be observed and further research must be carried out in various active environments to confirm these results clinically.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.640-646
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• 2008

This study was conducted to evaluate the breadmaking characteristics of white bread when rice bran (RB), fermented rice bran (FRB) and rice bran oil (RBO) were added to the dough. Addition of RB to dough generally showed a decrease of the bread volume and increase of the bread weight which is related to the comparative decrease of gluten in the dough. Addition of RB also showed a decrease of lightness with yellowish color of RB and showed some rheological changes in dough. However, up to 5% RB addition, the dough showed a similar property of breadmaking with giving functional benefits compared to the control. Moreover 5% FRB addition to the dough improved the taste, flavor, and texture important to quality of bread. Substitutional use of RBO for shortening in dough result in comparative decrease of volume of dough. Addition of yellowish RBO influenced the increasing yellowness score, hardness, gumminess and brittleness, which is disadvantageous for the quality of white bread. However up to 50% RBO substitution for shortening made little rheological differences compared to the control. The 50% RBO substitution for shortening increased the score of flavor in sensory test even if there was an unfavorable quality point of white bread caused by a decreased volume and an increased hardness. From these results it could be suggested that the proper use of RB, FRB and RBO in breadmaking could improve the taste and flavor, giving beneficial function originated from rice bran to white bread.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.359-366
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• 2005

Effects of neutron beam irradiation on seed germination, growth and RAPD pattern of tobacco (Nicotiana tabacum L. cv.; N. plumbaginifolia) and rice (Orya sativa L. cv.) plants were estimated. Seed germination rate was not significantly changed by the neutron beam treatment in both tobacco and rice seeds. And there was no significant differance in growth of the plants by the neutron beam treatment. Interestingly, however, some of morphological changes, including leaf shape (about $36\%$), stem color and leaf color were observed in neutron beam treated tobacco plants. In addition, abnormal flower in petal was observed in the neutron beam treated plant. This results indicate that neutron beam is able to use as an effective mutagen in plant mutations. Scorable products from 20 primers were obtained by RAPD analysis in the leaves of the beam irradiated tobacco plants and most of the plants showed the similar band patterns.

• Journal of Energy Engineering
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• v.7 no.1
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• pp.146-156
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• 1998

Fly ash produced in coal combustion is a fine-grained material consisting mostly of spherical, glassy, and porous particles. A physical, morphological, and chemical characteristic of fly ash has been analyzed. This study may contribute to the data base of domestic fly ash, the improvement of combustion efficiency, ash recycling and ash collection in the electrostatic precipitator. The physical property of fly ash is determined using a particle counter for the measurement of ash size distribution and gravimeter. Morphological characteristic of fly ash is performed using a scanning electron micrograph and an optical microscope. The chemical components of fly ash are determined using an inductively coupled plasma emission spectrometry (ICP). The distribution of fly ash size was ranged from 15 to 25 $\mu$m in mass median diameter. Exposure conditions of flue gas temperature and duration within the combustion zone of the boiler played an important role on the morphological properties of the fly ash such as shape, relative opacity, coloration, cenosphere and plerosphere. The spherical fly ash might be generated at the condition of complete combustion. The size of fly ash was found to be increased the with particle-particle interaction of agglomeration and coagulation. Fly ash consisted of $SiO_2\;Al_2O_3\;and\;Fe_2O_3$ with 85% and carbon with 3~10% of total mass.

• Research in Plant Disease
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• v.15 no.3
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• pp.259-261
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• 2009

Sclerotinia shoot rot of Grapevine(Vitis labruscana) occurred at Gapyeong and Yeongwol area from 2003 to 2005. Infected plants showed shoot blight at the one-year-old fruit bearing branches. The first visible symptom noticed was wilting and blighting of the branches. The obvious and typical initial symptom is the presence of a cottony, white, dense mat of mycelial growth on the surface of the diseased lesions. The base or stem of the infected young shoots develop a pale brown rotted area, which girdled and killed shoots. In advanced stages of the disease, stems and branches became bleached and eventually died. The isolates collected from diseased grapevine stem were identified as Sclerotinia sclerotiorum based on the morphological and cultural characteristics. The pathogenicity test revealed that Vitis vinifera(cultivar: Kyoho) was stronger than V. labruscana(cultivar: Campbell early) to the pathogen. This is the first report on sclerotinia shoot rot of grapevine in Korea.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.995-1000
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• 2004

Nutritional composition and antioxidative capacity of mulberry fruit (Ficus-4x) were investigated for evaluation as new red-colored fruit. Contents of moisture, crude fat, crude protein, and vitamin C were similar, whereas that of crude ash was higher, to those of other berry fruits. Contents of minerals (Ca, 14.33 mg/100 g; P, 39.98 mg/100 g; Fe, 6.01 mg/100 g; Zn, 4.04 mg/100 g; Mn, 2.26 mg/100 g), particularly Fe, were higher than those of other berry fruits. Hardness, springness, cohesiveness, gumminess, and chewiness of mulberry fruit were higher, and color values (L, 36.03; a, 1.80; b, 1.54) were lower than those of strawberry. Relative scavenging activities of mulberry fruit methanol extract and its cyanidine 3-glucoside on 1, 1-diphenyl-2-picrylhydrazy radical (DPPH) were 35.7 and 78.2%, respectively, using butylated hydroxyanisole (BHA) as standard. Antioxidant activities in corn oil (peroxide values and conjugated dienoic acid) were tertiary butylhydroquinone (TBHQ) > mulberry fruit ethanol extract > mulberry fruit water extract > butylated hydroxytoluene (BHT) > tocopherol. Results show mulberry fruit can be very useful red-colored fruit for development of functional foods with beneficial effects on radical scavenging and antioxidative capacities.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.588-596
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• 1996

The optimum conditions of the 1st and 2nd distillation had been investigated to obtaine a high quality monomeric MDI and fire reactive polymeric MDI by purification of crude MDI. Effect of additives on the monomeric MDI's color change, dimerization and the reactivity of polymeric MDI with standard polyol system has been tested. When the monomeric MDI yield is approximately 32%, 4,4'-MDI content is above 98% in the monomeric MDI at the 1st distillation. When the separation ratio of initial portion and residue percentage, reflux ratio are set at respectively, approximately 20wt%, 9wt%, above 2 in order to minimize the content of 2,4'-MDI in monomeric MDI, the freezing point of final distilled monomeric MDI is above $38.4^{\circ}C$. Since the monomeric MDI is inherently unstable in the room condition, monomeric MDI easily changes it's color and conducts self-polymerization reaction. To increase the stability of monomeric MDI, the composition of antioxidant, which is composed of phenolic 1st antioxidant, phosphorus 2nd antioxidant, UV absorbent and Hindered amine light stabilizer are used, and benzoyl chloride as antipolymerization agent test are that APHA color is less than 20, dimer content is remained less than 0.36wt% after 45 days storage of monomeric MDI.