조수리소설창작적예술특색

민혜정 대한중국학회 1995 중국학 Vol.10 No.-

LC-MS/MS를 이용한 담배 중 Amadori Compounds의 분석

민혜정,김영회,이정민,장기철,Min, Hye-Jeong,Kim, Young-Hoi,Lee, Jeong-Min,Jang, Gi-Chul 한국연초학회 2011 한국연초학회지 Vol.33 No.1

Amadori compounds(1-deoxy-1-amino-2-ketoses) are important precursors of color, flavor and aroma produced in foods. Amadori compounds occur naturally in tobacco. The contribution of amadori compounds to smoke quality has been (of) interest because of their roles of the Maillard reaction in the leaf chemistry. The amounts of these compound in tobacco are affected by the processes of aging, drying and storage conditions. In this study, eight compounds were chemically synthesized because amadori compounds (have not been sold commercially these days.) were not available for obtaining commercially. The aim of this study was to develop the analytical method of amadori compounds in tobacco leaf by the liquid chromatography mass spectrometry using triple quadrupole analyzer(LC-MS/MS). This method was simple, rapid, selective and sensitive, and eight amadori compounds were simultaneously and quantitatively analyzed within 20 minutes. This method showed excellent accuracy and precision. Recovery rates of amadori compounds ranged from 86% to 102%, with relative standard deviation(RSD) ranged from 2.6% to 5.9%. This method was applied to analysis of amadori compounds contents of tobacco leaves in different varieties. Furthermore, it was expected that the method could be extended to the analysis of other amadori compounds.

한국의 학교에 다니고 있는 친구들에게

민혜정 한국국어교육학회 1997 세계가 한동네 Vol.1997 No.-

HPLC를 이용한 잎담배 중 유기산 함량 분석

민혜정,장석수,김익중,신준원,김용하,민영근,Min, Hye-Jeong,Jang, Seok-Su,Kim, Ick-Joong,Shin, Jun-Won,Kim, Yong-Ha,Min, Young-Keun 한국연초학회 2006 한국연초학회지 Vol.28 No.2

This study was carried out to improve the analytical methods for determination of organic acids in tobacco leaf by HPLC. The samples for HPLC analysis were pre-treated by means of SPE. The calibration curve for each acid was linear and $R^2$ values ranged from 0.9990 to 1.0000. The limit of detection were obtained from the calibration curves and their values were between 1.39 to $4.87{\mu}g/mL$. Recovery rates of organic acids were between 88.6 % to 98.5 %. The concentrations of organic acids among the various tobacco leaves were compared to the concentration of organic acids, were in the order oriental, burley, flue-cured tobacco. In the case of flue-cured and oriental tobacco leaves, the order of concentration of organic acids was malic acid, oxalic acid, citric acid. But in the case of burley tobacco leaves, the order of concentration of organic acids was citric acid, oxalic acid, malic acid.

인공후두 제어원으로서의 흉골설골근 사용의 타당성 검증

민혜정,봉정표 대한의용생체공학회 1996 의공학회지 Vol.17 No.2

We have been studying an implant type EMG-controlled electrolarynx. First of all, we propose the sternohyoid muscle(SH) as a control source of the electrolarynx. The purpose of this study is to investigate the possibility that subjects control voluntarily the constriction of their SH, and produce the control signals of electrolarynx. For this pwnan, we carried out four experiments regarding the control of the electrolarynx. At the results, we found that subjects can control the start/stop of constriction and the amplitude of EMG of their SH. Also, we ascertained the possibility that the start/stop of contraction of SH controls OW/OFF of sound source of the electrolarynx and the amplitude of UG of SH controls the pitch frequency of the electrolarynx.

바실러스 아밀로리퀘페이션스 대사산물을 이용한펩타이드 천연 화장품방부제에 관한 연구

민혜정 한국미용학회 2018 한국미용학회지 Vol.24 No.3

In this study, we investigated a peptide natural cosmetic preservative that is safe to human and can replace chemical preservatives. The peptide mixture was extracted from a culture broth of Bacillus amyloliquefaciens which is used for various applications such as food fermentation, production of bioactive materials, and environment-friendly biocontrol agents, and was examined for its applicability as a natural cosmetic preservative. The LC-MS analysis of the bacillus culture extract revealed that it contains various cyclic lipopeptides (iturin, fengycin and surfactin) exhibiting antimicrobial activities. The antimicrobial activity of the extract was tested against three Grampositive, three Gram-negative bacteria, and one fungus using paper disc diffusion and minimum inhibitory concentration experiments. The extract showed a broad spectrum of antimicrobial activity with MIC values of less than 750 mg/mL for both bacteria and fungus. In particular, the extract showed very strong antimicrobial activity with MIC of 31.3 mg/mL against Staphylococcus aureus strain which is directly related to a skin atopic dermatitis. To examine the extract as a natural preservative for cosmetics, the toner formulation including the bacillus culture extract was prepared and tested for bacterial killing effects against Escherichia coli and Staphylococcus aureus. This test showed much stronger bactericidal activity than a conventional plant-derived natural preservative at the same concentration. Thus, this study suggested that the bacillus culture extract containing antimicrobial cyclic lipopeptides could be a peptide-based natural preservative for cosmetic applications.

근전위 제어형 인공후두의 설계

민혜정,최홍식,윤형로,봉정표 대한후두음성언어의학회 1997 대한후두음성언어의학회지 Vol.8 No.1

In this Paper, we developed an electrolarynx controlled by the EMG(electromyography) of the sternohyoid muscle, and rested the property of the new electrolarynx while normal persons with his own larynx use it. for the examination of property of the developed electrolarynx, our researchers performed three different experiments. The first experiment was tested whether that on/off control of the vibrator of the electrolarynx is synchronized with the activity of the sternohyoid EMG. In the second experiment, it was tested when the lower amplitude of the sternohyoid EMG is produced, whether the higher pitch of the electrolarynx is produced, and vice versa. The third experiment was tested the probability that the electrolarynx can produce the voiceless sound. As the results, we found that the developed electrolarynx had the good produce of the on/off vibrator control and the pitch control of the electrolarynx. Also, we ascertained the possibility that it can produce the voiceless sound.

안개꽃

민혜정 중앙대학교 1987 無影燈 Vol.12 No.1

고효율 컬럼과 RRLC를 이용한 담배 주류연 중 페놀 화합물의 분석 효율화

민혜정,강영희,이정민,장기철,Min, Hye-Jeong,Kang, Young-Hee,Lee, Jeong-Min,Jang, Gi-Chul 한국연초학회 2010 한국연초학회지 Vol.32 No.1

This study was carried out to enhance the analytical methods of phenolic compounds in mainstream cigarette smoke using high efficiency column and RRLC(Rapid Resolution Liquid Chromatography) system, and to compare these methods. RRLC system offers significantly faster results with higher data quality of phenolic compounds than conventional HPLC, but it is disadvantage that it is expensive. On the other hand, the method using monolithic column offers faster results by the use of conventional HPLC system without new equipment introduction. In this study, we used the linear type smoking machine and Health Canada method for pre-treatment process of phenolic compounds. The analysis time of phenolic compounds using RRLC and monolithic column was individually 8 and 15 minutes, whereas in the conventional HPLC it was 45 minutes. These new methods were accompanied with the minimal solvent consumption and had lower analysis costs. Also, we proved that there were no difference between new methods and conventional method in accuracy by statistic.

펩타이드 천연 화장품 방부제 개발

민혜정 한국유화학회 2017 한국유화학회 학술대회 논문집 Vol.2017 No.3

최근 화장품은 남녀노소를 불문하고 선택이 아닌 필수품으로 사용되고 있어 화장품시장과 산업규모는 계속해서 확대되고 있다. 또한 다양한 기능을 가지는 화장품 소재들의 개발은 화장품이 외적 아름다움을 위한 역할과 피부 건강을 유지하고 향상시키는 적극적인 기능을 기대할 수 있게 한다. 그러나 미생물에 취약한 화장품들의 안정성 확보를 위해 필수적으로 사용되어 왔던 기존 합성방부제들의 문제점과 천연유래성분들을 선호하는 소비자들의 욕구는 천연 화장품 방부제를 함유한 안전한 화장품들을 요구하고 있다. 현재까지 알려진 천연방부제들은 색상, 냄새, 안정성, 좁은 항균스펙트럼, 지속성, 제형개발의 어려움, 비용적인 한계성을 보이고 있어 널리 상용화 되지 못하고 있다. 최초의 항생제인 페니실린을 포함하여 많은 항균물질들이 천연에서 분리되어 사용되어 왔으며 특히 미생물로부터 분리된 천연 항생물질은 기존의 항생제에 내성을 갖는 내성 균주에도 효과를 보인다는 점에서 착안하여 본 연구를 시작하였다. 특히 바실러스균은 발효 식품등에 존재하는 인체에 유용한 균의 하나로써 iturin, fengycin, surfactin 등 다양한 펩타이드성 항생물질을 만들어 냄으로써 세균이나 곰팡이 등 유해한 균의 생장을 억제하거나 사멸함으로써 항균작용을 나타낸다. 본 연구에서는 국내에서 분리된 바실러스균을 이용하여 배양액으로부터 주요 활성물질들을 추출하였다. 그 중에서 펩타이드성 항생 물질들을 동정 후 항균활성을 검정하였으며, 항균활성 배양액 추출물 속의 펩타이드성 항생물질들을 기반으로 한 천연화장품 방부제 개발을 진행 중에 있다. 배양액 추출물은 다양한 세균과 곰팡이에 대해 강한 항균작용을 나타내었고 몇 가지 화장품 제형에 적용하였을 때도 우수한 항균능력을 보였다. 본 연구에서 개발 중인 펩타이드 천연 화장품 방부제의 또 다른 장점은 펩타이드라는 특성상 물질 자체가 인체에 비교적 무해하며 무색, 무취이므로 제형적용에 용이하다는 것이다. 따라서 바실러스균의 배양액에서 추출한 다양한 항균활성을 나타내는 펩타이드를 기반으로 한 천연소재는 기존의 합성방부제들을 대체 할 새로운 천연 화장품 방부제로의 개발 가능성을 보여주고 있다.