지방산 칼륨 Cream Soaps 의 상거동 연구

노민주,여혜림,이지현,박명삼,이준배,윤명석 사단법인 대한화장품학회 2022 대한화장품학회지 Vol.48 No.1

The potassium cream soap with fatty acid called cleaning foam has a crystal gel structure, and unlike an emulsion system, it is weak to shear stress and shows characteristics that are easily separated under high temperature storage conditions. The crystal gel structure of cleansing foams is significantly influenced by the nature and proportion of fatty acids, degree of neutralization, and the nature and proportion of polyols. In order to investigate the effect of these parameters on the crystal gel structure, a ternary system consisting of water/KOH/fatty acid was investigated in this study. The investigation of differential scanning calorimeter (DSC) revealed that the eutectic point was found at the ratio of myristic acid (MA) : stearic acid (SA) = 3 : 1 and ternary systems were the most stable at the eutectic point. However, the increase in fatty acid content had little effect on stability. On the basis of viscosity and polarized optical microscopy (POM) measurements, the optimum degree of neutralization was found to be about 75%. The system was stable when the melting point (Tm) of the ternary system was higher than the storage temperature and the crystal phase was transferred to lamellar gel phase, but the increase in fatty acid content had little effect on stability. The addition of polyols to the ternary system played an important role in changing the Tm and causing phase transition. The structure of the cleansing foams were confirmed through cryogenic scanning electron microscope (Cryo-SEM), small and wide angle X-ray scattering (SAXS and WAXS) analysis. Since butylene glycol (BG), propylene glycol (PG), and dipropylene glycol (DPG) lowered the Tm and hindered the lamellar gel formation, they were unsuitable for the formation of stable cleansing foam. In contrast, glycerin, PEG-400, and sorbitol increased the Tm, and facilitated the formation of lamellar gel phase, which led to a stable ternary system. Glycerin was found to be the most optimal agent to prepare a cleansing foam with enhanced stability. Cleansing foam이라 불리는 지방산 칼륨 cream soap은 crystal gel 구조로 이루어져 있어 유화계와는달리 전단응력에 약하며 고온의 보관조건에서 쉽게 분리되는 특성을 보여준다. Crystal gel 구조는 지방산의종류 및 비율, 중화도, polyol의 종류와 사용량에 따라 크게 영향을 받는다. Crystal gel 구조에 미치는 이들의영향을 조사하기 위해 water/potassium hydroxide (KOH)/fatty acid ternary system에서 실험을 실시하였다. Differential scanning calorimeter (DSC) 측정 결과 myristic acid (MA) : stearic acid (SA) = 3 : 1 비율에서공융점(eutectic point)를 갖고 이 혼합비가 가장 안전한 삼성분계(ternary system)를 만든다는 것을 발견했다. 점도 측정과 편광현미경 (POM) 관찰 결과 중화도는 75% 부근이 최적이라고 판단된다. 삼성분계의 melting point (Tm)이 보관온도보다 높을 때, 그리고 crystal phase가 lamellar gel phase로 상 전이가 일어날 때 안정하나지방산 함량의 증가는 안정성에 거의 영향을 미치지 않는다. 삼성분계에 polyol의 첨가는 Tm을 변화시키고 상전이를 일으키는데 중요한 역할을 한다. 클렌징폼의 구조는 저온 주사전자현미경 (Cryo-SEM), 소각 및 광각X-선 산란 (SAXS, WAXS) 분석으로 규명하였다. Butylene glycol (BG), propylene glycol (PG), dipropylene glycol (DPG)은 Tm을 낮추어주며 lamellar gel phase 형성을 어렵게 하는 반면 glycerin, PEG-400, sorbitol은Tm을 상승시키고 lamellar gel phase 형성을 용이하게 하며 안정한 삼성분계를 만든다.

쉘락/젤라틴을 함유한 저자극 · 친환경 매니큐어의 개발

심하은,노대영,김지민,김도연,남명석,김동욱 한국화학공학회 2019 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.57 No.7

Nail polish is used to decorate nail beautifully however, it contains lots of toxic materials. Generally, Nail polish consists of film-forming agent, colorant, solvent, surfactant and stabilizer. In this study, to replace toxic chemicals to low irritative, eco-friendly ingredients, we prepared 4 kinds of nail polish and tested safety, stability and performance. Nail polish including shellac/gelatin showed best performance in water-resistance, friability and drying time. When cell toxicity test is done by MTT assay, shellac-gelatin nail polish showed over 70% cell viability at 1,000 μg/mL whereas control nail polish in market showed 50% cell viability. At 4 weeks temperature stability test, color was stable at low temperature however it needs formulation improvement at higher temperature. 매니큐어는 손톱을 아름답게 꾸미기 위해 사용하는 색조화장품이지만 그 구성성분은 유해성분이 상당히 포함되어있다. 매니큐어는 일반적으로 피막형성제, 색소, 용제, 계면활성제 및 침전방지제 등으로 구성되어 있다. 본 연구에서는유해성 성분을 저자극, 친환경적인 성분으로 대체하여 4종의 매니큐어를 제조하고, 매니큐어로서 효력 비교실험과 안전성 및 안정성 시험을 실시하였다. 효력비교실험에서 쉘락/젤라틴 매니큐어 조성물(No. 4)이 내수성 및 적당한 강도를 지니면서 건조시간이 2분 내외로 대조군(4분 내외)보다 우수하고 악취도 개선되어, 피막형성제로서 가장 우수한 특성을 보여주었다. 또한 쉘락/젤라틴 매니큐어 조성물의 세포독성시험 결과, 1,000 μg/mL 농도에서 70% 이상의 세포생존율로 시판되고 있는 매니큐어(50% 세포생존율)보다 독성이 낮았다. 4주간 온도 안정성 시험에서 저온에서는 색상의변화가 없었으나, 상온과 고온에서 외관상변화 및 점도변화가 관찰되어 추후 제형의 개선이 필요한 것으로 생각된다.

Recent Trends in Integrative Insect Nutrition:A Nutritional Geometry Perspective

이광범,장태환,노명석 한국응용곤충학회 2022 한국응용곤충학회지 Vol.61 No.1

Nutrition dictates nearly all biological processes and determines Darwinian fitness in all living organisms, including insects. Research on insect nutrition has a long history in the field of insect physiology and the importance of understanding insect nutrition has become increasingly apparent with the growing need for producing insects as food and feed. Nevertheless, it is only in recent years that we have witnessed a major breathrough in our knowledge of insect nutrition. The multivariate, interactive, and dynamic nature of nutrition has long hampered our complete understanding of insect nutrition. However, the challenge posed by such nutritional complexity has been overcome with the advent of the Nutritional Geometry, which is an integrative and multidimensional framework that enabled us to model complex interactions between multiple nutrients. In this review, we introduce the basic concepts and principles of the Nutritional Geometry and describe how this innovative framework has revolutionized the field of insect nutrition and has placed nutrition in the centre of the interface between physiology, ecology, and evolution. We close this review by discussing potentially fertile research areas that can benefit tremendously from the application of this powerful nutritional paradigm in the future.

퍼지논리 기반 실시간 전류, 전압 특성을 활용한 과전류 계전기 정정 방법에 관한 연구

신동엽(Dongyob Shin),윤명석(Myungseok Yoon),유재현(Jaehyun Yoo),노주안(Juan Noh),최승연(Sungyun Choi) 한국조명·전기설비학회 2022 한국조명·전기설비학회 학술대회논문집 Vol.2022 No.11

쉘락/젤라틴을 함유한 저자극 · 친환경 매니큐어의 개발

심하은 ( Haeun Shim ),노대영 ( Daeyoung Noh ),김지민 ( Jimin Kim ),김도연 ( Doyeon Kim ),남명석 ( Myungsuk Nam ),김동욱 ( Donguk Kim ) 한국화학공학회 2019 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.57 No.1

Nail polish is used to decorate nail beautifully however, it contains lots of toxic materials. Generally, Nail polish consists of film-forming agent, colorant, solvent, surfactant and stabilizer. In this study, to replace toxic chemicals to low irritative, eco-friendly ingredients, we prepared 4 kinds of nail polish and tested safety, stability and performance. Nail polish including shellac/gelatin showed best performance in water-resistance, friability and drying time. When cell toxicity test is done by MTT assay, shellac-gelatin nail polish showed over 70% cell viability at 1,000 μg/mL whereas control nail polish in market showed 50% cell viability. At 4 weeks temperature stability test, color was stable at low temperature however it needs formulation improvement at higher temperature.

라멜라 액정상 메이크업 클렌징 제형

여혜림 ( Hye Lim Yeo ),이지현 ( Ji Hyun Lee ),김수지 ( Su Ji Kim ),노민주 ( Minjoo Noh ),장지희 ( Ji Hui Jang ),김연준 ( Youn Joon Kim ),윤명석 ( Moung Seok Yoon ),유권종 ( Kweon Jong Yoo ),이준배 ( Jun Bae Lee ) 대한화장품학회 2017 대한화장품학회지 Vol.43 No.1

본 연구는 두 개의 편광판 사이에서 홀로그램과 같은 독특한 외관을 갖는 라멜라 액정상 메이크업 클렌징 제형에 관한 것이다. 라멜라 액정상을 갖는 메이크업 클렌징 제형 연구는 오래전부터 많이 시도되어 왔지만, 탁도 증가 및 점도 상승 등의 문제로 실제 상용화에는 한계가 있었다. 본 연구에서는 이러한 문제를 해결하기 위해 계면활성제의 알킬 체인에 의한 액정상의 유동성 증가와 음이온 계면활성제 도입에 따른 정전기적 반발력 증가를 이용하였다. 이를 통해 액정상의 결정화를 억제하여 안정한 액정상 제형을 확보할 수 있었다. 또한, 본 연구에서는 객관적이고 정량적인 클렌징력 평가를 위해 형광물질과 in vivo imaging system (IVIS) 장비를 이용하여 in vitro 클렌징력 평가법을 새롭게 도입하였다. 이렇게 개발된 클렌징력 평가법을 이용하여 라멜라 액정상 메이크업 클렌징 제형의 우수한 메이크업 클렌징력을 확인할 수 있었다. 한편, 본 연구에서 개발된 라멜라 액정상 메이크업 클렌징 제형을 직교 배열된 두 편광판 사이에 두면 홀로그램과 유사한 특이적인 무늬를 관측할 수 있다. 이러한 현상은 액정상 제형을 통과하는 가시광선과 라멜라 구조 사이의 간섭현상에 의한 것으로 추정된다. 클렌징 제형에서의 라멜라 구조는 소각 X선 산란분석(SAXS)을 이용하여 Bragg spacing ratio가 1 : 2의 정수 비로 관찰되는 것을 통해 확인하였다. 본 연구를 통해 개발된 라멜라 액정상 메이크업 클렌징 제형은 우수한 경시 안정성과 클렌징력, 그리고 편광판 사이에서 관찰되는 홀로그램과 유사한 독특한 외관으로 인해 향후 새로운 메이크업 클렌징 제품 개발에 도움이 될 것으로 기대된다. This study is related to a lamellar liquid crystal make-up cleansing formulation with a hologram-like unique appearance between two polarizing plates. Make-up cleansing formulations with a lamellar liquid crystal phase have been extensively studied for a long time, but there have been limitations in practical commercialization because of increasing turbidity and viscosity. In this study, to solve this problem, alkyl chains of surfactants were modified to increase the fluidity of the liquid crystal phase, and electrostatic repulsion force was increased by introducing anionic surfactant. The lamellar liquid crystal make-up cleansing formulation which introduced anionic surfactants can easily inhibit crystallization through electrostatic repulsion force, thereby showing excellent stability overtime, maintaining transparent appearance and viscosity. In addition, we have newly introduced an in vitro cleansing evaluation method using fluorescent material and in vivo imaging system (IVIS) for objective and quantitative cleansing ability evaluation. The excellent cleansing ability of lamellar liquid crystal cleansing formulation has been confirmed by newly developed evaluation method. On the other hand, when lamellar liquid crystal make-up cleansing formulation was placed between orthogonally arranged two polarizing plates, a specific pattern like a hologram can be observed. This phenomenon is presumably interpreted as the interference between the visible light passing through the liquid crystal formulation and the lamellar structure. The lamellar structure of cleansing formulation was confirmed by SAXS analysis, exhibiting Bragg spacing ratio of 1 : 2. The lamellar liquid crystal make-up cleansing formulation prepared in this study would be useful for future application in make-up cleansing due to its excellent stability, cleansing ability, and unique hologram-like pattern placed between two polarizing plates.