• Food Science and Biotechnology
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• 제15권2호
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• pp.317-320
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• 2006

Octadeca-9,12-dienyl-3,4,5-hydroxybenzoate (GA-LA) was chemically synthesized from gallic acid and linoleic acid ester, and its biological functions were tested. Radical-scavenging activity of GA-LA was comparable to those of gallic and ascorbic acids at 0.24 mM, and tyrosinase inhibition effect was higher than that of ascorbic acid. Gallic and linoleic acids did not show any tyrosinase activity. Results of cyclooxygenase (COX) inhibition effect indicate GA-LA has higher selectivity in COX-1 inhibition. GA-LA from gallic and linoleic acids could be used as functional reagent for antioxidative, skin-whitening, and anti-inflammatory effects in food, pharmaceutrical, and cosmetic industries.

• Natural Product Sciences
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• 제20권2호
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• pp.126-129
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• 2014

Bioactivity-guided investigation on whole plant of Euphorbia supina, using LPS-induced Raw264.7 cells, led to the identificaiton of a tannin which was not reported from this plant along with four known constituents (quercetin, astragalin, juglanin and methyl gallate). The structure of the tannin was determined as corilagin by the interpretation of NMR (1D and 2D) and MS spectroscopic data. All the isolates were tested for the inhibitory activity against NO production in LPS-induced Raw264.7 cells. Among the tested isolates, corilagin was found to be the most active compound.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제18권3호
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• pp.175-190
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• 2015

연구에서는 게임개발을 위한 팀 프로젝트 활동이 수학영재의 공동체배려와 조직관리능력 기술에 미치는 효과를 확인하고 영재를 위한 리더십교육의 방향을 제시하고자 하였다. G교육지원청 영재교육원 초등수학반 4학년 학생을 대상으로 연구를 수행한 결과, 영재학생들은 15차시의 팀 프로젝트 활동을 통해 공동체배려와 조직관리능력 요인의 기술점수가 유의미하게 향상되었으며, 이는 동료들과 함께 수학이론 학습, 게임규칙 확인, 게임 개발 아이디어 회의, 게임 자료 제작, 산출물발표 준비 등의 과정을 경험하며 성장한 것으로 나타났다. 이러한 결과는 전공과목과 분리된 리더십교육이 아닌 수업주제의 특성과 융합된 리더십교육으로도 영재학생들에게 리더로서의 역량을 길러줄 수 있음을 시사한다.

• Food Science and Biotechnology
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• 제17권6호
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• pp.1197-1202
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• 2008

Present study investigated the effects of the 70% ethanol extracts of tissue-cultured mountain ginseng (TCMG), Korean red ginseng (KRG), and Panax ginseng (PG) on agonist-induced platelet aggregation and activation in human whole blood. The $IC_{50}$ values for TCMG, KRG, and PG were 1.159, 3.695, and 4.978mg/mL for collagen-induced aggregation, 0.820, 2.030, and 4.743mg/mL for arachidonic acid-induced aggregation, and 1.070, 2.617, and 2.954 mg/mL for ADP-induced aggregation, respectively. Also, this study assessed the effects of the most active extract, TCMG, on markers of platelet activation by determining receptor expression on platelet membranes in healthy subjects, including expression of GPIIb/IIIa-like (PAC-1) and P-selectin (CD62), by flow cytometry. A significant decrease in PAC-l expression (p=0.018) was observed in the presence of TCMG. These results show that TCMG has potent anti-platelet activity.

• 공학교육연구
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• 제25권1호
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• pp.55-64
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• 2022

In this paper, the characteristics of peer-evaluation and self-evaluation of team activity participation in project-based learning and their usability were investigated. The characteristics of peer-evaluation and self-evaluation are as follows. First, in peer-evaluation and self-evaluation of project-based learning, the correlation between the two evaluation scores was very high. When students' scores from their peers correlate very well with the scores they give themselves, it means that they apply the same criteria to their peers and to themselves when evaluating team activity. Second, there was no difference in peer-evaluation and self-evaluation scores between groups with different written test scores. The fact that peer-evaluation and self-evaluation scores do not change according to academic ability shows that the two evaluation areas are independent. Third, the self-evaluation score in project-based learning is statistically significantly higher than the score received from peers. This raises doubts about the fairness of self-evaluation. Therefore, in this paper, it is suggested that self-evaluation of team activities in project-based learning is carried out together with peer-evaluation, but only peer-evaluation is reflected in credits.

• 한국축산식품학회지
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• 제40권1호
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• pp.87-95
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• 2020

In this study, we separated and purified lipase inhibitory peptide from fermented milk by Lactobacillus plantarum Q180 with the aim of developing a new functional anti-lipase activity yogurt product. L. plantarum 180 was inoculated into 10% reconstituted skimmed milk and incubated at 37℃ until the pH of the culture reached pH 4.4. The lipase activity was measured using porcine pancreatic lipase. The lipase inhibitory peptides were gradually isolated by ultrafiltration, reversed phase column chromatography (RPC), reversed phase high-performance liquid chromatography (RP-HPLC), and gel permeation high-performance liquid chromatography (GP-HPLC) from the fermented milk by L. plantarum Q180. An ODS-AQ column was used for the RPC, a Vydac C18 column for the RP-HPLC, and a Superdex Peptide HR column for the GP-HPLC. The peptide was composed of Asp, Thr, Ile, Ser, Ala, and Gln, and the anti-lipase activity (IC₅₀) was 2,817 ㎍/mL.

• 한국균학회지
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• 제48권1호
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• pp.15-27
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• 2020

본 연구에서는 methicillin resistant Staphylococcus aureus subsp. aureus (MRSA) KCCM 40510 및 Bacillus cereus KCTC 3624 균주에 대한 항균활성을 보유한 균류 Penicillium rubefaciens NNIBRFG5039를 경북 상주시 도남동 공기 중으로부터 분리·동정하였고, 배양조건에 따른 균사체 생육 및 항균활성을 비교하였다. 그 결과, P. rubefaciens NNIBRFG5039는 PDB 배지, 배양온도 30℃, 초기 pH 6.5로 배양하였을 때 항균활성이 가장 높게 나타나는 것을 확인하였다. 최적조건하에서 5L fermenter를 이용하여 배양시간에 따른 균사체 건조중량 및 항균활성을 비교한 결과, 배양 5일째에 생장 및 항균활성이 가장 높았다. P. rubefaciens NNIBRFG5039의 배양여액의 항균활성 스펙트럼을 조사한 결과, methicillin-resistant Staphylococcus aureus subsp. aureus CCARM 3089·3090·3091·3095와 KCCM 40510, Bacillus cereus KCTC 3624, B.subtilis KACC 10111, Filobasidium neoformans KCTC 7902, Enterococcus faecalis KCCM 11814에 대해서도 항균활성을 가지는 것을 확인하였다. 또한, P. rubefaciens NNIBRFG5039의 배양여액으로부터 항균활성 후보물질을 각종 크로마토그라피법으로 순수분리하고, NMR과 ESI-MS 등의 기기분석을 실시하여 구조를 (S)-6-hydroxymellein (1)으로 동정하였다.

• 한국축산식품학회지
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• 제38권1호
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• pp.135-142
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• 2018

Recently, research on the processing of raw functional materials with the aim of improving various physiological activities has been conducted. In this study, we investigated the antioxidant activity of royal jelly (RJ) hydrolysates obtained from three commercial proteases. Enzyme-treated royal jelly (ERJ), in which the RJ hydrolysates were converted into easy-to-absorb shorter chain monomers through the removal of two known allergen proteins, showed no difference in the content of (E)-10-hydroxydec-2-enoicacid (10-HDA) or the freshness parameter and showed a significant increase in total free amino acid content. The antioxidant activity of ERJ was determined by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and chemical assays. The ERJ showed about 80% DPPH-radical scavenging activity at same concentration of ascorbic acid. The antioxidant effect of ERJ was confirmed to be due to reduction of intracellular reactive oxidative species (ROS) and nitric oxide (NO) production in LPS-treated macrophages. Moreover, ERJ significantly increased the activity of the antioxidant enzyme superoxide dismutase (SOD) and the level of the antioxidant glutathione (GSH) in a dose-dependent manner. Interestingly, these antioxidant activities of ERJ were stronger than those of non-treated RJ. These findings indicate that ERJ has high potential as an antioxidant agent for use in human and animal diets.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.359-366
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• 2013

Although many research efforts have been conducted to address the effect of crew members' work skills (e.g., technical and planning skills) on work performance (e.g., work duration and quality) in construction projects, the relationship between skill and performance has generated a great deal of controversy in the field of management (Inkpen and Crossan 1995). This controversy can lead to under- or over-estimations of the overall project schedule, and can make it difficult for project managers to implement appropriate managerial policies for enhancing project performance. To address this issue, the following aspects need to be considered: (a) work performances are determined not only by individual-level work skill but also by the group-level work skill affected by work team members, each member's role, and any working behavior pattern; (b) work planning has significant effects on to what extent work skill enhances performance; and (c) different types of activities in construction require different types of work, skill, and team composition. This research, therefore, develops a system dynamics (SD) model to analyze the effects of both individual-and group-level (i.e., multi-level) skill on performances by utilizing the advantages of SD in capturing a feedback process and state changes, especially in human factors (e.g., attitude, ability, and behavior). The model incorporates: (a) a multi-level skill evolution and relevant behavior development mechanism within a work group; (b) the interaction among work planning, a crew's skill-learning, skill manifestation, and performances; and (c) the different work characteristics of each activity. This model can be utilized to implement appropriate work planning (e.g., work scope and work schedule) and crew management policies (e.g., work team composition and decision of each worker's role) with an awareness of crew's skill and work performance. Understanding the different characteristics of each activity can also support project managers in applying strategic work planning and crew management for a corresponding activity, which may enhance each activity's performance, as well as the overall project performance.

• 지식경영연구
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• 제14권5호
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• pp.101-120
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• 2013

The effective management of knowledge has become one of the critical success factors in current organizations. In spite of the extensive use of Knowledge Management System (KMS), useful information and knowledge resources are still transmitted through personal networks among people in organizations. Thus, social network theory which focuses on social relationships in organization can be a fruitful theoretical resource for enhancing Knowledge Management (KM) performances. In this study, we investigate the effects of intra-team network characteristics (i.e., group density and degree of centralization) and external boundary spanning activities on knowledge management performances of a team. We also acknowledge that all group members do not necessarily agree on the team goal and actively disseminate useful information and knowledge. Drawing on the political perspective on KM which emphasizes the role of trust among group members, we examine the mediating effects of team trust between internal/external network characteristics and KM performances. From the data of 220 teams in financial companies in Korea, we found that: (1) group density had positive effects on KM performances (i.e., knowledge creation, sharing, and use). (2) However, centralization was not significantly associated with KM performances. (3) Team trust was found to be an important factor mediating the relationship between intra-team network characteristics, boundary spanning activities, and KM performances. Based on these results, we discuss and suggest possible implications of the findings when designing and implementing KM practices.