• Proceedings of the KACD Conference
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• 2001.11a
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• pp.564.2-564
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• 2001

For the purpose of explaining the mechanism of tooth discoloration caused by tetracycline (TC), a study was conducted by setting up the following in vitro system. Being evaluated were the TC concentration to give an optimum reaction state when it acted on hydroxyapatite(HA) granules and the absorbing wavelength of TC that had been irradiated with ultraviolet (UV) rays.(omitted)

• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.1202-1205
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• 2000

Germicidal lamps efficiently emit a large amount of ultraviolet rays 253.7nm which have excellent germicidal effect. The lamps are primarily useful for sterilization of air, the surface of various materials and water or liquid. In this paper, analysis of the charge pump power factor correction inverter for driving a 65W UV lamp and electrical characteristics of the lamp are discussed. The operation of the inverter circuit. in which the lamp is included as a load, is analyzed. Experimental results of the inverter circuit are also presented.

• Korean Journal of Microbiology
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• v.10 no.2
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• pp.73-78
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• 1972

As the first step in the production of nucleic acid derivatives by microorganisms, adenineless mutants were derived from Brevibacterium ammoniagenes ATCC6872. A culture of Br. ammoniagenes was exposed to ultraviolet rays for 120 second and treated with diethylsulfate in phosphate buffer for 2 hours to reach the designed death rate. The yield of mutants induced was 0.28% by the ultraviolet irradiation and 0.66% by the diethylsulfate treatment. By the diethylsulfate treatment. By the treatment of penicillin G in a hypertonic minimal medium, the yield of mutants was increased from 0.28% to 0.54% and from 0.66% to 1.5%, respectively. Thus, in was demonstrated that diethylsulfate treatment was much more efficient than UV irradiation to induce adenineless mutants of the bacteria, and total strains of 120 adenineless mutants were obtained.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.299-306
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• 2016

In this study, new hydroxyapatite powder surface composites were investigated for protective effects against ultraviolet rays. Hydroxyapatite (HAp) is biocompatible and does not cause nebula phenomenon on skin. We investigated the surface modification of hydroxyapatite to improve UV block and skin usage. Dimethicone, lauroyl lysine, triethoxycaprylylsilane and silica were used as coating agents for the surface modification of HAp. To prepare the composite complex of the modified surface, the dimethicone, lauroyl lysine and triethoxycaprylylsilane were prepared by a dry process, and silica by a hydrothermal synthesis method. The HAp-silica was chosen as the best composite powder when measuring its sun protection levels. We investigated the characteristics of the surface of HAp-silica by SEM, particle size analyzer and energy dispersive spectrometry (EDS). Additionally, the stability in the formulation, UV block effect, and safety in BB creams were investigated. In conclusion, HAp-silica prepared by the modification of HAp complex surface improved the skin usage and UV block effect by enhancing the white cloudy phenomenon. These results indicate that HAp-silica may be used for UV block cosmetics.

• Journal of Periodontal and Implant Science
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• v.50 no.4
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• pp.238-250
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• 2020

Purpose: This study aimed to evaluate the biocompatibility and the mechanical properties of ultraviolet (UV) cross-linked and biphasic calcium phosphate (BCP)-added collagen membranes and to compare the clinical results of ridge preservation to those obtained using chemically cross-linked collagen membranes. Methods: The study comprised an in vitro test and a clinical trial for membrane evaluation. BCP-added collagen membranes with UV cross-linking were prepared. In the in vitro test, scanning electron microscopy, a collagenase assay, and a tensile strength test were performed. The clinical trial involved 14 patients undergoing a ridge preservation procedure. All participants were randomly divided into the test group, which received UV cross-linked membranes (n=7), and the control group, which received chemically cross-linked membranes (n=7). BCP bone substitutes were used for both the test group and the control group. Cone-beam computed tomography (CBCT) scans were performed and alginate impressions were taken 1 week and 3 months after surgery. The casts were scanned via an optical scanner to measure the volumetric changes. The results were analyzed using the nonparametric Mann-Whitney U test. Results: The fastest degradation rate was found in the collagen membranes without the addition of BCP. The highest enzyme resistance and the highest tensile strength were found when the collagen-to-BCP ratio was 1:1. There was no significant difference in dimensional changes in the 3-dimensional modeling or CBCT scans between the test and control groups in the clinical trial (P>0.05). Conclusions: The addition of BCP and UV cross-linking improved the biocompatibility and the mechanical strength of the membranes. Within the limits of the clinical trial, the sites grafted using BCP in combination with UV cross-linked and BCP-added collagen membranes (test group) did not show any statistically significant difference in terms of dimensional change compared with the control group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.6
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• pp.833-839
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• 2003

Quantitaties of flavonoids were determined by HPLC in three different ethanol extract (50, 70 and 95%, v/v) from Korean cherry. Antimicrobial activity of the ethanol extract and its solvent fraction (ethyl acetate and n-butanol fractions) against Staphylococcus aureus (ATCC 6538) and Staphylococcus epidermidis (ATCC 12228) was evaluated using MIC and disk test. Additionally, UV protective effect was also determined. The highest flavonoid quantity was found in 70% ethanol extract of Korean cherry. The quantities of quercitrin were 12.7 mg% and 2.1 mg% in ethyl acetate fraction and in buthanol fraction, respectively. In addition, the flavonoid in 70% (v/v) ethanol extract of Korean cherry included 14.9 mg% of quercitrin, 6.0 mg% of tannic acid and 5.2 mg% of catechin. Therefore, it was confirmed that main flavonoid of Korean cherry was quercitrin. For antimicrobial activity of ethanol extract of Korean cherry against Staphylococcus aureus (ATCC 6538) and Staphylococcus epidemidis (ATCC 12228), MIC and disk test using ethyl acetate fraction and butanol fraction were carried out. As a result, ethyl acetate fraction with higher quantity of flavonoid showed higher antimicrobial activity. Therefore, it was confirmed that the higher antimicrobial activity was brought about by flavonoid in Korean cherry. For UV protective effect of Korean cherry, ethanol extract showed the absorption zone of ultraviolet rays in 210∼380 nm including 290∼320 nm that is the wave length of UV-B harmful to the skin of human body. The pattern is the same as the absorption zone of 220∼300 nm in catechin and 210∼400 nm in quercitrin. Then, the functionalities of catechin and quercitrin were anticipated. It is expected that quercitrin in Korean cherry has the antimicrobial effect and UV protective effect related to the skin.

• Journal of the Korea Convergence Society
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• v.12 no.1
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• pp.251-257
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• 2021

ln this study, natural extracts extracted from cypress sapiens, a natural material, were investigated as materials that could protect skin aging caused by ultraviolet rays, and experiments were conducted on the synthesis of filaggrins that make up the natural moisturizing factor of the skin, the synthesis of pro-colagen, a fibrous protein, which plays an important role in moisturizing the dermis, and elastin, which is an enzyme that decomposes collagen. As a result, cypress ethanol extract (COE) was a dependent inhibitor to collagenase and elastase, inhibiting the synthesis of filaggrin and the expression of MMP-1 for exfoliated cells damaged by ultraviolet rays. Therefore, it is estimated that ethanol extract will have the effect of delaying wrinkles and as a functional cosmetic material that inhibits skin aging convergence. Based on this study, we would like to further study the mechanism of the synthesis of filaggrin on the suppression of expression of MMP, which is the anti-wrinkle effect.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.32 no.4 s.59
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• pp.227-231
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• 2006

Wrinkle formation is mainly attributed to the environmental factors such as UV rays, air pollution, smoking and stress etc. Especially, UV rays induce premature skin aging which is characterized by deep wrinkle, leathery dryness etc. Recently, researches on the wrinkle formation and its prevention have been the main theme in cosmetics fields. We have studied the various plant extracts having anti-wrinkle effects and finally showed that Noni (Morinda citrifolia) extracts have the efficacy of promoting the type I collagen synthesis in normal human fibroblast, using PICP assay. We purified one active compound from Noni extracts and identified its structure. It was identified as 6,7-Dimethoxy-2H-1-Benzopyran-2-one; scopoletin by $^1H-NMR,\;^{13}C-NMR,$ IR, Mass analysis. Scopoletin increased collagen synthesis in a dose dependent manner (89.5% at $0.2{\mu}g/mL$). In order to verify the anti-aging effectiveness of the cream containing 3% noni extracsts, we performed the in vivo test with some female volunteers for 12 weeks. It reduced the signs of aging, especially face wrinkles. From these results, we conclude that the noni extracts could be used as an useful anti-wrinkle agent.

• Journal of Acupuncture Research
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• v.32 no.2
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• pp.1-9
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• 2015

Objectives : The present study was an evaluation and standardization of herbal components in order to establish the efficacy and safety of Shinbaro pharmacopuncture. Methods : Among the raw materials of Shinbaro pharmacopuncture, the components Cibotii Rhizoma, Eucommiae Cortex, and Ledebouriellae Radix were assessed through ingredient verification experiments using thin-layer chromatography(TLC) and ultraviolet rays(UV) lamps. In addition, we standardized Acanthopanacis Cortex and Achyranthis Radix through validation using high performance liquid chromatograph-diode array detector(HPLC-DAD). Results : As result appeared a blue-white fluorescence under ultraviolet rays; changed to dark green after adding 1 % ferric chloride solution(due to Cibotii Rhizoma), and presented a yellow-green fluorescence when mixed with an ethyl ether under UV lamps by way of the ethyl ether layer, confirming Eucommiae Cortex. Ledebouriellae Radix was confirmed as dark brown spots at Rf values of 0.56 and 0.71 using TLC. Additionally, Acanthopanacis Cortex and Achyranthis Radix HPLC test results showed that linearity was $R^2{\geq}0.99$, and detection limit and quantitation limit were 0.23 to $1.29{\mu}g/mL$, and 0.71 to $3.90{\mu}g/mL$, respectively. Furthermore, precision and accuracy were confirmed to have relative standard deviation(RSD) values of 0.10 to 1.89 % and 96.19 to 103.72 %, respectively. Shinbaro pharmacopuncture did not have any overlapping or interference from other peaks in detection under the abovementioned analysis conditions. Conclusions : In conclusion, we confirmed that maintenance of Shinbaro pharmacopuncture validity was possible by means of quality control of Cibotii Rhizoma, Eucommiae Cortex, and Ledebouriellae Radix through ingredient identification and Acanthopanacis Cortex and Achyranthis Radix through high performance liquid chromatograph(HPLC) analysis. Further, we hope to contribute to the development strategy of herbal industry acupuncture.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.41-46
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• 2014

The property improvement of polycarbonate coated with a multilayer film composed of an inorganic $SiO_2$ film and a photocatalytic $TiO_2$ film was studied. The $SiO_2$ film as a binder had an excellent light transmission characteristic. After the treatment with atmospheric pressure plasma, the surface of $SiO_2$ film showed the hydrophilicity, which increased the film coating uniformity with a $TiO_2$-containing aqueous solution. When $TiO_2$ film was over 200 nm thick, the absorption effect of UV rays in the range of 180~400 nm suppressed the yellowing phenomena of polycarbonate substrate. The inorganic film improved the heat resistance of polycarbonate substrates. $TiO_2$ film in the outmost under the exposure of UV rays promotes the catalytic oxidation characteristics and yields the capability to the decomposition of organic contaminants, and also increases the self-cleaning properties due to the increase of hydrophilicity. Structural stability of the polycarbonate substrate coated with inorganic $TiO_2$ and $SiO_2$ film was shown. The role of $SiO_2$ film between $TiO_2$ and polycarbonate substrate suppressed the peeling of $TiO_2$ film by inhibiting the photocatalytic oxidation effect of $TiO_2$ film on the polycarbonate substrate.