Development of an Analytical Approach for the Utilization of Edible Tree Sprouts

Jungwon Choi,김주리,이학동,조혜진,Leo Adrianne Paje,Hanna Shin,이상현 한국생약학회 2022 Natural Product Sciences Vol.28 No.1

This study evaluated the general nutritional ingredients such as crude fats, crude ashes, crude proteins, total polyphenols, and total flavonoids in 18 kinds of edible tree sprouts. The tree sprouts of Philadelphus schrenckii, Lycium chinense, and Morus alba had the highest crude fat, crude ash, and crude protein content, respectively. The tree sprouts of Cedrela sinensis (CSS) with high ABTS+ radical scavenging activities had a high content of total polyphenols (175.65 mg/g ext.) and total flavonoids (75.18 mg/g ext.). The simultaneous determination of flavonoids such as rutin, isoquercitrin, quercitrin, afzelin, and quercetin in CSS was conducted using high-performance liquid chromatography with a wavelength of 270 nm. Among the flavonoids, the content of quercitrin in CSS was the highest at 59.28 mg/g ext. This study also aids the quality control of many edible tree sprouts by analyzing the general components, total polyphenols, and total flavonoids.

Simultaneous determination of saikosaponin derivatives in Bupleurum falcatum by HPLC-ELSD analysis using different extraction methods

( Jungwon Choi ),( Juree Kim ),( Sam Sik Kang ),( Sanghyun Lee ) 한국응용생명화학회(구 한국농화학회) 2021 Journal of Applied Biological Chemistry (J. Appl. Vol.64 No.1

Saikosaponin derivatives such as saikosaponins A, B1, B2, B3, B4, C, and D present in Bupleurum falcatum were analyzed by a high performance liquid chromatograph equipped with an evaporative light scattering detector, using different extraction solvents (water and 70% ethanol). The samples were injected into a YMC Pack Pro C₁₈ column and separated using a gradient elution system with a mobile phase composed of acetonitrile and water at a flow rate of 1.1 mL/min. The content of saikosaponin derivatives was higher in 70% ethanol extract than in water extract. This study provides an efficient analytical method for determining the optimal conditions for extraction of saikosaponin derivatives, which can be used as a basis for development of functional foods and pharmaceutical products from B. falcatum.

REP1 Modulates Autophagy and Macropinocytosis to Enhance Cancer Cell Survival

Choi, Jungwon,Kim, Hyena,Bae, Young Ki,Cheong, Heesun MDPI 2017 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.18 No.9

<P>Rab escort protein 1 (REP1), a component of the Rab geranyl-geranyltransferase 2 complex, plays a role in Rab protein recruitment in proper vesicles during vesicle trafficking. In addition to having well-known tissue degenerative phenotypes in the REP1 mutant, REP1 is tightly associated with cancer development and contributes to cell growth and survival. However, the functional mechanism of REP1 in cancer progression is largely uninvestigated. Here, we show that REP1 plays a crucial role in regulating mammalian target of rapamycin (mTOR) signaling and its downstream pathways, as well as autophagy and macropinocytosis, which are essential for cancer cell survival during metabolic stresses including starvation. REP1 small interfering RNA (siRNA) treatment downregulates mTORC1 activity in growing media, but blocks autophagosome formation under nutrient-depleted conditions. In contrast to the mild decrease of lysosomal enzyme activity seen in REP1 depletion, in REP1 knockdown the subcellular localization of lysosomes is altered, and localization of REP1 itself is modulated by intracellular nutrient levels and mTOR activity. Furthermore, REP1 depletion increases macro pinocytosis which may be a feedback mechanism to compensate autophagy inhibition. Concomitant treatment with macropinocytosis inhibitor and REP1siRNAresults in more significant cell death than autophagy blockade with REP1 knockdown. Therefore, REP1-mediated autophagy and lysosomal degradation processes act as novel regulatory mechanisms to support cancer cell survival, which can be further investigated as a potential cancer-targeting pathway.</P>

A Study on an Experience Exhibition Space for the Hearing-disabled using Ubiquitous Technology

Jungwon Choi,Hyunsuk Son,Yongseong Kim 한국콘텐츠학회 2009 ICCC International Digital Design Invitation Exhib Vol.2009 No.12

Modern Korea beings are more likely to pay attention to and spend time in leisure activities amid rapidly changing economic growth. However, unluckily, there are less cultural facilities and feasible plans for the disabled in spite of more efforts to set up environments for them. The purpose of this study is to present an exhibition space where the hearing-disabled can experience for themselves and meet their needs through applying ubiquitous technology. With ubiquitous technology applied for the disabled and to the space, auditory data could be imagined via visual means. This study presented a space where the handicapped can have more optimized experiences by applying ubiquitous technology while enhancing their limited hearing ability form visual and tactile means, in order to get information on sounds and rhythms.

Quantitative analysis of cordycepin in Cordyceps militaris under different extraction methods

( Jungwon Choi ),( Leo Adrianne Paje ),( Baekjun Kwon ),( Jaekyu Noh ),( Sanghyun Lee ) 한국응용생명화학회(구 한국농화학회) 2021 Journal of Applied Biological Chemistry (J. Appl. Vol.64 No.2

Cordyceps militaris (CM) is one of the most important medicinal mushrooms known to possess various biological activities. Cordycepin (CP) is a bioactive compound present in the fruiting bodies of CM and is known to have anti-tumor, anti-metastatic immunomodulatory and anti-inflammatory activities. In this study, we aim to analyze CP quantitatively under various CM extraction conditions. CP was measured using high-performance liquid chromatography, quantified using a reversed phase column using a gradient elution system of water and acetonitrile, and detected with a UV absorbance wavelength of 260 nm. The CP content of CM was the highest in 100% ethanol extract of the fruiting bodies and 60% ethanol extract of the mycelium. This study provides an efficient analysis method to determine the optimal extraction conditions for CP that can be used as a basis for developing functional foods and pharmaceutical products derived from CM.

Antioxidative phenolic compounds from the aerial parts of Cyperus exaltatus var. iwasakii and their HPLC analysis

Choi Jungwon,Lee Hak-Dong,Cho Hyejin,Lee Chang-Dae,Tran Gia Han,Kim Hoon,Moon Sung-Kwon,Lee Sanghyun 한국응용생명화학회 2023 Applied Biological Chemistry (Appl Biol Chem) Vol.66 No.-

The constituents and antioxidant activities of Cyperus exaltatus var. iwasakii (CE) have not been studied to date. In this study, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6 sulfonic acid) (ABTS) assays were used to evaluate the radical-scavenging activities of the ethanol extract, four fractions, and isolated compounds of CE. In addition, phenolic acids and flavonoids were isolated from the ethanol extract of CE using column chromatography. The compounds identified by spectroscopy were gallic acid, protocatechuic acid, vanillic acid, p-coumaric acid, rutin, ferulic acid, isoquercitrin, astragalin, quercetin, luteolin, apigenin, tricin, and kaempferol. Quantitative analysis using high-performance liquid chromatography (HPLC) revealed that the major flavonoids of CE were astragalin and tricin and that the major phenolic acid was p-coumaric acid. In addition, comparative analysis of CE from Ganghwa and Hampyeong habitats using HPLC showed that the Hampyeong CE had a higher phytochemical content. Comparative analyses of the isolated compounds were also conducted among five Cyperus species. The highest antioxidant activities were found in the ethyl acetate (EtOAc) fraction, and among the compounds isolated from CE, vanillic acid and quercetin showed remarkable antioxidant activity even when compared with ascorbic acid. The results demonstrate the usefulness of CE, which has not been sufficiently studied previously, and will facilitate the evaluation of its potential effectiveness as antioxidant functional plant material.

Resource Allocation for H-FDD OFDMA Systems

Choi, Jihwan P.,Jaesub Shin,Jungwon Lee,Hui-Ling Lou,Ji-Woong Choi IEEE 2014 IEEE communications letters Vol.18 No.7

<P>Half-frequency-division duplexing (H-FDD) has recently attracted attention since it can serve as a cost-effective solution for machine-to-machine (M2M) communication networks. This letter proposes a method to jointly optimize resource allocation, mobile station grouping, and frame partitioning for H-FDD orthogonal frequency-division multiplexing access systems. We develop a near-optimal and low-complexity algorithm that is also applicable to frequency-division duplexing and time-division duplexing as special cases. Simulation results demonstrate that our algorithm with reduced computation can provide performance close to that of the optimal but time-consuming exhaustive search.</P>

Crystal structure of the C107S/C112S mutant of yeast nuclear 2-Cys peroxiredoxin

Choi, Jongkeun,Choi, Soonwoong,Chon, Jae Kyung,Choi, Jungwon,Cha, Mee-Kyung,Kim, Il-Han,Shin, Whanchul Wiley Subscription Services, Inc., A Wiley Company 2005 Proteins Vol.61 No.4

부모 학대와 또래 애착이 지역아동센터 이용 아동의 공격성 변화에 미치는 영향: 잠재성장모형을 중심으로

최정원(Choi, Jungwon),조은영(Jo, Eunyoung) 한국청소년정책연구원 2020 한국청소년연구 Vol.31 No.1

본 연구의 목적은 지역아동센터를 이용하고 있는 아동을 대상으로 초등학교 5학년부터 중학교 2학년까지 공격성의 변화양상을 파악하고, 부모 학대 및 또래 애착이 공격성의 변화에 어떠한 영향을 미치는지 알아보는 것에 있다. 본 연구는 보건복지부와 지역아동센터중앙지원단의 위탁을 받아 한국청소년정책연구원에서 수집한 지역아동센터아동패널조사 2기 데이터 중 2차년도(630명)에서 5차년도(346명)까지의 자료를 사용하였다. 자료의 일반적 경향을 살펴본 후, 공격성의 변화양상과 공격성의 변화궤적에 영향을 미치는 요인을 탐색하기 위해 잠재성장모형을 적용하여 분석하였다. 본 연구의 주요 결과는 다음과 같다. 첫째, 공격성은 초등학교 5학년부터 중학교 1학년까지 감소하다가 중학교 1학년 이후로는 그 수준이 유지되는 것으로 나타났으며, 이러한 변화율에 개인차가 있는 것으로 나타났다. 둘째, 부모 학대 및 또래 애착은 같은 시점의 공격성에 영향을 미치는 것으로 나타났다. 즉, 부모가 방임하거나 학대를 많이 할수록 아동의 공격성이 높아지는 반면, 또래와의 관계에서 긍정적인 유대감을 느낄수록 공격성은 낮아졌다. 또한, 부모 학대와 또래 애착은 공격성의 변화양상에도 영향을 미치는 것으로 나타났다. 즉, 부모 학대 수준이 높을수록 공격성의 감소폭이 줄어들고, 또래 애착 수준이 높을수록 공격성의 감소폭은 큰 것으로 나타났다. 이러한 연구결과는 지역아동센터 이용 아동을 대상으로 공격성의 변화양상과 선행요인에 대한 정보를 제공하였으며, 향후 이들의 공격성 감소를 위한 상담 및 교육 프로그램을 위한 기초자료로 활용될 수 있을 것으로 기대된다. The purpose of this study was to examine the trajectories of the aggression of children using community child centers and to identify the effects of parental abuse and peer attachment on the aggression of children from a longitudinal perspective. The 2<SUP>nd </SUP>panel data from the 2<SUP>nd</SUP> year(n =630) to 5th year(n =346) of the community child center children panel survey was used. We conducted a descriptive statistical analysis and utilized the multivariate latent growth model. The results were as follows. First, it was found that levels of aggression decreased from the 5<SUP>th</SUP> to the 7<SUP>th</SUP> grade. Second, parental abuse and peer attachment predicted children’s initial level of aggression (intercepts) and their rate of increase of aggression (slope). This study confirmed the longitudinal impact of parental abuse and peer attachment on the aggression levels of children using community child centers. Based on these results, the implications of this study and future research tasks were also discussed.

청소년의 민감성과 우울 간의 관계: 부모 양육행동의 조절효과를 중심으로

최정원(Choi, Jungwon),김주현(Kim, Joohyun),강현지(Kang, Hyunjee) 한국청소년정책연구원 2020 한국청소년연구 Vol.31 No.2

민감성 연구의 대표적인 학자인 Aron은 민감성과 부정적 정서 간의 관계에 있어 양육환경의 역할을 강조하였다. 본 연구는 국내 청소년들을 대상으로 민감성과 우울 및 부모 양육행동 간의 관계를 살펴보고, 민감성과 우울 간의 관계에서 부모 양육행동의 조절효과를 알아보고자 수행되었다. 이를 위해 서울 및 경기 지역에 소재한 중고등학교에 재학 중인 283명을 대상으로 민감성 척도, 부모 양육행동 척도, 우울 척도를 사용한 자기보고식 설문조사를 실시하였다. 수집된 자료는 기술통계 및 Pearson의 적률상관분석과 Process macro의 조절효과모형을 이용하여 분석하였다. 주요 연구결과는 다음과 같다. 첫째, 청소년의 심미성 지각이 높을수록 우울을 적게 경험하는 반면, 자극 불편감이 높을수록 우울을 많이 경험하는 것으로 나타났다. 그리고 자녀가 부모의 부정적 양육행동을 높게 지각할수록, 긍정적 양육행동을 낮게 지각할수록, 청소년들은 우울을 더 많이 경험하였다. 둘째, 자극 불편감과 부정적 양육행동의 상호작용 효과가 유의했다. 구체적으로, 자극 불편감이 우울에 미치는 영향은 부정적 양육행동이 높을수록 심화되는 것으로 나타났다. 그리고 정서적 전이와 긍정적 양육행동의 상호작용 효과가 유의했다. 구체적으로, 정서적 전이가 우울에 미치는 영향은 긍정적 양육행동이 높을수록 완화되는 것으로 나타났다. 이러한 결과를 통하여 부모의 양육행동이 청소년의 민감성과 우울 간의 관계에서 조절역할을 하는 것을 확인하였으며, 이는 청소년의 민감성이 발현되는 데 있어 부모의 역할이 매우 중요함을 시사한다. The purpose of this study was to investigate the moderating effects of parenting behaviors in the relationship between sensitivity and depression of adolescents. A total of 283 students were recruited from middle and high school in the Seoul and Gyeong-gi areas. The data were analyzed by means of Pearson’s correlations and moderation model using PROCESS macro. The major findings of the study were as follows. First, depression showed negative associations with aesthetic awareness and positive parenting behaviors. In contrast, depression exhibited positive associations with discomfort from external stimuli and negative parenting behaviors. Second, negative parenting behaviors moderated the influence of discomfort from external stimuli on depression, whereas positive parenting behaviors moderated the influence of emotional transference on depression. These results suggest that adolescents’ sensitivity can serve as either a risk or a protective factor when it comes to depression, with this being dependent upon the quality of the parenting adolescents receive.