• Journal of Life Science
• /
• v.31 no.3
• /
• pp.305-313
• /
• 2021

This study verified the antioxidant and whitening activities of a Pinus koraiensis extract (PK) and a Hibiscus cannabinus L. extract (HC), and further evaluated the interaction of the extract ingredients when mixed at a 1:1 ratio (PKHC). The electron-donating and ABTS+ radical scavenging activities of the PKHC extract at 1,000 ㎍/ml concentration were 93.7% and 94%, respectively, indicating a higher efficacy than achieved with either extract alone. Measurements of the tyrosinase the activities in response to PK, HC, and PKHC extracts at 1,000 ㎍/ml concentrations showed inhibitions of 40%, 27.5%, and 43%, respectively, confirming a higher efficacy of the mixture due to the synergistic action of the ingredients. The cell toxicity values in melanoma cells treated with PK, HC, and PKHC at 1,000 ㎍/ml concentration were 87.4%, 80.2%, and 98%, confirming a higher viability in cells treated with the mixture due to antagonism. The expression of microphthalmia-associated transcription factor (MITF), tyrosinase-related protein-1 (TRP-1), tyrosinase-related protein-2 (TRP-2), and tyrosinase protein expression determined by Western blotting decreased by 53.9%, 64.8%, 67.3%, and 56.1%, respectively, when PKHC was administered at a concentration of 100 ㎍/ml. Reverse transcription-polymerase chain reaction (RT- PCR) results also showed that PKHC at a concentration of 100 ㎍/ml inhibited the mRNA expression of MITF, TRP-1, TRP-2, and tyrosinase mRNA by 54.4%, 64.9%, 66.6%, and 63.1%, respectively. Taken together, the data confirmed the antioxidant and whitening effect of the PKHC extract and verified the possibility that this extract mixture has great potential as a cosmetic ingredient.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.3
• /
• pp.534-546
• /
• 2023

In this study, we investigated the antioxidant and anti-winkle activity in human fibroblast cell (CCD-986sk) of Persimmon Leaves (PL) as a cosmetic ingredient. As a result of investigating antioxidant activity through electron-donating ability and ABTS⁺ radical scavenging assay, the PL showed concentration-dependent antioxidant activity similar to ascorbic acid, a control group, at a concentration of 1,000 ㎍/ml. As a result of investigating the anti-wrinkle effect through elastase inhibition and collagenase inhibition assay, the PL showed concentration-dependent antioxidant activity similar to epigallocatechin gallate, a control group, at a concentration of 1,000 ㎍/ml. As a result of measuring the synthesis rate of pro-collagen type I and the inhibition rate of MMP-1 in UVB-induced CCD-986sk cells, the control group EGCG showed a 90.2% pro-collagen synthesis rate at 20 ㎍/ml and PL showed an 88.5% synthesis rate at 30 ㎍/ml. In addition, the inhibition rate of MMP-1 of 33.0% and 40.8% were confirmed in EGCG 20 ㎍/ml and PL 30 ㎍/ml, respectively. As a result of measuring the protein expression of pro-collagen type I and MMP-1 in the PL through western blot, it was confirmed that the protein expression of pro-collagen type I increased, and MMP-1 decreased when the PL was treated together compared to the UVB alone group. According to the above experimental results, it is expected to be used as a natural product material for cosmetics by confirming that the PL prevent photoaging caused by UVB stimulation and have antioxidant and anti-wrinkle effects.

• Korean Journal of Environmental Biology
• /
• v.30 no.3
• /
• pp.210-218
• /
• 2012

The morphological characteristics, carbon and nitrogen concentrations, stable isotope values and photosynthetic rates of Porphyra yezoensis were studied at the main purple lavers production areas on southwestern coast of Korea. The morphological characteristics of leaf length, leaf width and weight of Porphyra blades were between 11.6~16.3 (average 13.8) cm, 4.6~6.3 (average 5.4) cm, $1.1{\sim}2.6(average\;1.86)g\;DW\;m^{-2}$, respectively. Photosynthetic pigment of Chl a concentration of Porphyra blades was between $2.18{\sim}17.77(average\;9.65)mg\;DW\;Chl\;a\;m^{-2}$. Carbon and nitrogen concentrations of Porphyra blades was between $201{\sim}317(average\;240)mg\;DW\;g^{-1}$, $39.8{\sim}50.0(average\;43.5)mg\;DW\;g^{-1}$ and C/N ratio 5.0~6.7 (average 5.5). The range of average ${\delta}^{13}C$ and ${\delta}^{15}N$ values of Porphyra blades was between - 25.6 to - 24.0 (average - 24.7)‰ for ${\delta}^{13}C$, and 1.3 to 4.1 (average 2.1)‰ for ${\delta}^{15}N$. Photosynthetic characteristics of seaweeds measured by pulse amplitude modulation (PAM) fluorometry was used as an indicator of photosynthetic activity. We use Diving-PAM fluorometry to examine photosynthetic rates of the seaweeds Porphyra yezoensis at each station. Maximum quantum yield of Porphyra blades was between 0.46~0.55 (average 0.52), the variance of the effective PS II maximum quantum yield of the station was broadly similar. Maximum relative electron transport rate (rETRmax) of Porphyra blades was between $4.71{\sim}5.84(average\;5.33){\mu}mol\;electrons\;m^{-2}\;s^{-1}$, the changes of maximum relative electron transport rate (rETRmax) of Porphyra yezoensis were similar to those of PS II maximum quantum yield. Photosynthetic efficiency (${\alpha}$) was between 0.027~0.045 (average 0.036). Minimum saturating irradiance ($E_k$) range was $139{\sim}180(average\;156){\mu}mol\;photons\;m^{-2}\;s^{-1}$. Minimum saturating irradiance ($E_k$) made a difference by station within the area on southwestern coast. Carbon and nitrogen concentrations and photosynthetic rates of Porphyra blades production areas on southwestern coast were broadly similar. The photosynthetic characteristics showed low photosynthetic rates because the low maximum quantum yields and low maximum relative electron transport rate.

• Journal of Technologic Dentistry
• /
• v.20 no.1
• /
• pp.37-49
• /
• 1998

The specimens used were Ag-25 Pd-15 Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electric furnace and centrifugal casting machine in Ar atmosphere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age- hardening characteristics of the small Au-containing Ag-Pd-Cu dental alloys were investigated by means of hardness testing. X-ray diffraction and electron microscope observations, electrical resistance, ergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, i.e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the $L1_0$ type face-centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affected by the Cu concentration. In stage II, decomposition of the ${\alpha}$ solid solution to a PdCu ordered phase($L1_0$ type) and an Ag-rich ${\alpha}2$ phase occurred and a discontinuous precipitation occurred at the grain boundary. From the electron microscope study, it was conclued that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipetation procedure was ${\alpha}{\to}{\alpha}+{\alpha}_2+PdCu {\to}{\alpha}_1+{\alpha}_2+PdCu$ at Pd/Cu = 1.7 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• Korean journal of food and cookery science
• /
• v.24 no.6
• /
• pp.905-911
• /
• 2008

Dried and roasted Gugija (Lycii fructus) were extracted with water, 50% ethanol and 100% ethanol, after which the physico-chemical properties of the extracts were evaluated. The extraction yield was higher when using water for the extraction solvent than when the other solvents were used, while the water extract of roasted Gugija had the highest yield. Furthermore the pH of the extracts increased as the ethanol concentration increased, and the pH of dried Gugija was higher than that of roasted Gugija when extracted using the same extraction solvent. The sugar concentrations of the extracts from dried and roasted Gugija were $15.0{\sim}20.1\;%Brix$ and $18.0{\sim}21.2\;%Brix$, respectively. The total polyphenol contents of the extracts from the dried and roasted Gugija were $6.9{\sim}19.0\;mg/g$ and $12.4{\sim}15.8\;mg/g$, respectively. Dried Gugija extract with water had a higher the total polyphenol contents than the other extract. The total polyphenol contents of roasted Gugija extracts were higher than those of dried Gugija, when using 50% or 100% ethanol for extraction solvent. The electron donating ability and total antioxidant activity of dried Gugija were $67.6{\sim}87.7%$ and $58.6{\sim}85.0%$, respectively, whereas those of roasted Gugija were $84.7{\sim}89.8%$ and $80.6{\sim}83.7%$, respectively. Dried and roasted Gugija extracts were higher electron donating ability and total antioxidant activity, when using water, and 50% or 100% ethanol, respectively. The predominant amino acid in all extracts was threonine. The essential amino acids constituted approximately $44.9{\sim}63.6%$ and $45.4{\sim}59.0%$ of the total amino acids of extracts from the dried and roasted Gugija, respectively. Finally, the total polyphenol contents and antioxidant activities showed that optimal extraction solvent would be water, and 50% or 100% ethanol for dried and roasted Gugija, respectively.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.23 no.3
• /
• pp.640-658
• /
• 1996

The purpose of this study was to examine the mechanism of improving acid resistance of Nd-YAG laser irradiated tooth enamel and determine the most effective energy density for improving acid resistance. The bovine tooth enamel were lased with a pulsed Nd-YAG laser. The energy densities of exposed laser beam were varied from 10 to $70\;J/cm^2$. To investigate the degree of improving acid resistance by irradiation, all the samples were submerged to demineralize in 0.5 N $HClO_4$ solution for 1 minute. After 1 minute, 0.05 % $LaCl_3$ was added to the solution for interrupting the demineralization reaction. The amounts of dissolved calcium and phosphate in the solution were measured by using an atomic absorption spectrophotometer and the UV/VIS spectrophotometer, respectively. To examine the mechanism of improving acid resistance, X-ray diffraction analysis, infrared spectroscopy, and scanning electron microscopy were taken. The X-ray diffraction pattern of the samples were obtained in the $10^{\circ}{\sim}80^{\circ}2{\theta}$ range with $Cu-K{\alpha}$ radiation using M18HF(Mac Science Co.) with X-ray diffractometer operating at 40 KV and 300 mA. The infra-red spectra of the ground samples in 300 mg KBr pellets 10 mm diameter were obtained in the $4000cm^{-1}\;to\;400cm^{-1}$ range using JASCO 300E spectrophotometer. The scanning electron microscopy was carried out using JSM6400(JEOL Co.) with $500{\sim}2000$ times magnification. The results were as follow 1. The concentration of calcium dissolved from laser irradiated enamel with $50J/cm^2$ was significantly lesser than that of unlased control group (p<0.05) 2. From the result of the X-ray diffraction analysis, $\beta$-TCP, which increases acid solubility, was identified in lased enamel but the diffraction peaks of (002) and (004) became sharp with increasing energy density of laser irradiation. This means that the crystals in lased samples were grown through the c-axis and subsequently, the acid solubility of enamel decreased. 3. The a-axis parameter was slightly increased by laser irradiation, whereas the c-axis parameter was almost constant except for a little decrease at $50J/cm^2$. 4. In the infra-red spectra of lased enamels, phosphate bands ($600{\sim}500cm^{-1}$), B-carbonate bands (870, $1415{\sim}1455cm^{-1}$), and A-carbonate band ($1545cm^{-1}$) were observed. The amounts of phosphate bands and the B-carbonate bands were reduced, on the other hand, the amount of the A-carbonate band was increased by increase the energy density. 5. The SEM experiments reveal that the surface melting and recrystallization were appeared at $30J/cm^2$ and the cracks were observed at $70J/cm^2$. From above results, It may be suggested that the most effective energy density for improving acid resistance of tooth enamel with the irradiation of Nd-YAG laser was $50J/cm^2$. The mechanism of improving acid resistance were reduction of permeability due to surface melting and recrystallization of lased enamel and reduction of acid solubility of enamel due to decrease of carbonate content and growth of crystal.

• Journal of Technologic Dentistry
• /
• v.19 no.1
• /
• pp.21-35
• /
• 1997

The Ag-Pd-Cu alloys containing a small amount of Au is commonly used for dental purposes, because this alloy is cheaper than Au-base alloys for clinical use. However, the most important characteristic of this alloy is age-hardenability, which is not exhibited by other Ag-base dental alloys. The specimens used were Ag-20Pd-20Cu ternary alloy and Au addition alloy. These alloys were melted and casted by induction electic furace and centrifugal casting machine in Ar atmoshpere. These specimens were solution treated for 2hr at $800^{\circ}C$ and were then quenched into iced water, and aged at $350{\sim}550^{\circ}C$ Age-hardening characteristics of the small Au-containing Ag-pPd-Cu dental alloys were investigated by means of hardness testing, X-ray diffraction and electron microscope observations, electrical resistance, differential scanning calorimetric, emergy dispersed spectra and electron probe microanalysis. Principal results are as follows : Hardening occured in two stages, I. e., stage I in low temperature and stage II in high temperature regions, during continuous aging. The case of hardening in stage I was due to the formation of the Llo type face centered tetragonal PdCu-ordered phase in the grain interior and hardening in stage I was affedted by the Cu concentration. In stage II, decomposition of the $\alpha$ solid solution to a PdCu ordered phase(L1o type) and an Agrich ${\alpha}2$ phase occurred and a discontiunous precipitation occurred at the grain boundary. Form the electron microscope study, it was concluded that the cause of age-hardening in this alloy is the precipitation of the PdCu ordered phase, which has AuCu I type face-centered tetragonal structure. Precipitation procedure was ${\alpha}\to{\alpha}+{\alpha}2+PdCu\to{\alpha}1+{\alpha}2+PdCu$ at Pd/Cu = 1 Ag-Pd-Cu alloy is more effective dental alloy as ageing treatment and is suitable to isothermal ageing at $450^{\circ}C$.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.11
• /
• pp.1485-1491
• /
• 2009

The biological compounds such as vitamin C, carotenoids, hesperidin and naringin were determined in Yuza grown in Geoje, Goseong, Gohung and Namhae. Also, activities of electron donating, nitrite scavenging and tyrosinase were detected by concentration of water extracts made from Yuza peel. Vitamin C contents of flesh sample were 6.34${\Pm}$0.12-10.74${\Pm}$1.25 mg/100 g and its contents of peel were 2.17-3.57 times higher than flesh. The carotenoid contents of peel were higher than flesh, and its contents were abundant (over 6.0 mg/100 g) in peel of Yuza grown in Goseong and Namhae-native, while Goheung-native and improved samples were detected below 3.6 mg/100 g. The contents of total phenols were the highest in flesh (11.11${\Pm}$0.10 mg/100 g) and peel (31.76 mg/100 g) of Namhae-improve Yuza. The contents of hesperidin and naringin were about 4.81-7.80, 3.07-4.62 times higher in peel than flesh. Electron donating ability of water extracts made from Yuza peel was 52.78${\Pm}$1.13-66.88${\Pm}$0.53%, in over 5 mg/mL; especially, its ability in Namhae sample was significantly high in reaction system added over 5 mg/mL of water extracts. Nitrite scavenging ability in all samples was below 30% in reaction system added 1 mg/mL of water extracts. Inhibition activity of tyrosinase in reaction system added 2.5 mg/mL of water extracts was only observed in Namhae samples, but the other samples were increased in reaction system added over 5 mg/mL of water extracts.

• Korean Journal of Food Science and Technology
• /
• v.45 no.1
• /
• pp.20-24
• /
• 2013

Food irradiation has recently become one of the most successful techniques to preserve food with increased shelf life. This study aims to analyze hydrocarbons in almonds (Prunus amygosalus L.) and peanuts (Arachis hypogaea) induced by electron beam irradiation. The samples were irradiated at 0, 1, 3, 5 and 10 kGy by e-beam and using florisil column chromatography fat, and content was extracted. The induced hydrocarbons were identified using gas chromatography-mass spectrometry (GC/MS). The major hydrocarbons in both irradiated samples were 1,7-hexadecadiene ($C_{16:2}$) and 8-heptadecene ($C_{17:1}$) from oleic acid, 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$) from linoleic acid and 1-tetradecene ($C_{14:1}$) and pentadecane ($C_{15:0}$) from palmitic acid. Concentrations of the hydrocarbons produced by e-beam were found to be depended upon the composition of fatty acid in both almonds and peanuts. The $C_{n-2}$ compound was found to be higher than $C_{n-1}$ compound in oleic acid and palmitic acid, while in case of linoleic acid, $C_{n-1}$compound was higher than $C_{n-2}$ compound. The radiation induced hydrocarbons were detected only in irradiated samples, with 1 kGy or above, and not in the non-irradiated ones. The production of 1,7-hexadecadiene ($C_{16:2}$), 8-heptadecene ($C_{17:1}$), 1,7,10-hexadecatriene ($C_{16:3}$) and 6,9-heptadecadiene ($C_{17:2}$), in high concentration gave enough information to suggest that these may be the possible marker compounds of electron beam irradiation in almonds and peanuts.

• Journal of Life Science
• /
• v.18 no.9
• /
• pp.1194-1201
• /
• 2008

Water temperature-dependent fluctuations of biochemical and molecular activities in the harmful dinoflagellate, Cochlodinium polykrikoides were studied. In terms of genomic DNA concentration, a similar value of 0.6 was observed at $12^{\circ}C$ and $15^{\circ}C$. However, DNA significantly increased beyond $18^{\circ}C$ (p<0.05), to a maximum of 1.8 at $24^{\circ}C$. DNA concentration significantly decreased to 0.6. The concentrations of RNA and total protein were likely at their highest values of 1.7 and 0.07 ${\mu}g$ $ml^{-1}$ at $24^{\circ}C$, respectively. RNA and total protein concentrations began to increase at $15^{\circ}C$. Oxygen availability between lower and higher temperatures was significantly different and increased from $18^{\circ}C$ according to light intensity, regardless of wavelengths (p<0.05). At $24^{\circ}C$, the highest value of the maximum electron transport rate ($ETR_{max}$), ranging from 537.9 (Ch 1) to 602.5 ${\mu}mol$ electrons $g^{-1}$ Chl ${\alpha}s^{-1}$ (Ch 4), was also apparent. Nitrate reductase (NR) and ATPase activities were at their highest values of 0.11 ${\mu}mol$ $NO_{2}^{-}$ ${\mu}g^{-1}$ Chl ${\alpha}h^{-1}$ and 0.78 pmol 100 $mg^{-1}$ at $24^{\circ}C$, respectively. In an analysis of CHN, the concentration of C and N also significantly increased (p<0.05). Most of the measurements for the cellular activities at $27^{\circ}C$, however, were less than at $24^{\circ}C$. These results suggest that the sub-cellular activities of C. polykrikoides are sensitive to changes in water temperature. It may be desirable to estimate at $18^{\circ}C$ the initiation of the massive blooming development of C. polykrikoides. In nature, it will be very difficult to maintain the massive blooms beyond $24^{\circ}C$ because of a possibly significant decrease in molecular activity of C. polykrikoides.