직접 메탄올 연료전지(direct methanol fuel cell, DMFC)는 연료의 개질 없이 메탄올 연료를 공급하여 수소이온과 전자 생성을 통해 전류를 생산하는 에너지 변환 장치이다. 현재 DMFC에 적용되고 있는 고분자 전해질 막(polymer electrolyte membrane, PEM)은 높은 수소이온 전도도와 물리화학적 안정성을 갖는 과불소화계 이오노머를 활용한 PEM이지만, 높 은 메탄올 투과율과 분해 시 발생되는 환경 오염 물질 등의 문제로 인해 신규 소재 개발이 요구되고 있다. 최근 들어, 과불소 화계 이오노머에 비해 낮은 연료 투과율 및 우수한 물리화학적 안정성을 갖는 탄화수소계 고분자 기반 PEM을 DMFC에 적 용하는 연구들이 보고되고 있다. 본 총설에서는 탄화수소계 고분자 기반 PEM 중 1) 친수성/소수성 영역의 뚜렷한 나노 상분 리 구조를 나타내는 가지형 공중합체를 합성하여 수소이온 전도성과 메탄올의 선택도를 향상시킨 연구, 2) 제막 단계에서 가 교 구조를 도입하여 메탄올 투과율을 감소시키고 치수 안정성을 향상시킨 연구, 3) 유/무기계 첨가제 및 다공성 지지체를 도 입하여 성능을 개선한 복합 막 개발 연구에 대해 소개하고자 한다.

We evaluated the protective effects of cricket methanol extract (CME) on ultra-violet B (UVB)-induced photoaging in human skin fibroblasts. The fibroblast cells were treated with 10, 50, and 100 μg/mL of CME for 24 h, and then exposed to UVB (30 mJ/cm2). CME showed a dose-dependent cytoprotective effect without any observable cytotoxicity. CME reduced UVB-induced production of reactive oxygen species (ROS) by 34.4, 34.9, 40.6% at concentrations of 10, 50, 100 μg/mL respectively. CME inhibited the release of matrix metalloproteinase (MMP) 1 and 3. Furthermore, CME also reduced UVB-induced collagen degradation in the fibroblast cells. Taken together, our data suggests that CME has a significant protective effect on UVB-induced photoaging of the skin. This benefit occurs through multiple mechanisms. The results also suggest a potential role for CME as an ingredient in anti-photoaging cosmetic products in the future.

Evodiae Fructus is the dried unripe fruit of Evodia rutaecarpa, and has traditionally been used for treating stomachache and diarrhea. Evodiamine and rutaecarpine, the major biologically active compounds of Evodiae Fructus, are reported to have anti-oxidative and anti-inflammatory effects, as well as inhibit proliferation and metastasis of various cancer cells. The current study investigates the anti-oxidative and anti-cancer effects of the Evodiae Fructus extract, considering varying concentrations of methanol extraction (40, 80, and 95%). High contents of total phenolic compounds were determined in the order of extracts 80, 95, and 40%. Evaluating contents of the 95, 80, and 40% extracts revealed 36.77, 7.29, and 1.86 μg/mg evodiamine, respectively, and 53.02, 17.16, and 3.79 μg/mg rutaecarpine, respectively, with the highest content of both compounds obtained in the 95% extract. DPPH radical scavenging activity was observed to be inversely proportional to the contents of total phenolic compounds, with decreasing SC50 values obtained in the order 80, 95, and 40% extract. The 95 and 80% extracts exerted toxicity to AGS gastric cancer cells, but the 40% extract was non-toxic. Evodiamine is a known anti-cancer agent, and could be responsible for the observed toxicity. Cleavage of PARP, and Caspase-3, -7, -8 and -9 was observed in the 95% extract-treated AGS cells, indicating that cell toxicity exerted by the 95% extract could be attributed to apoptosis.

In this study, we investigated the protective effects of Ulva lactuca methanol extracts against ultraviolet B (UVB)-induced DNA damage in HaCaT cells. First, the contents of general and antioxidative nutrient contents of Ulva lactuca were measured. The moisture, carbohydrate, crude protein, crude fat and ash were 14.01%, 44.80%, 23.19%, 3.10% and 14.90%, respectively. Magnesium that acts as DNA repair enzyme cofactor was the most abundant mineral followed by Ca, P and Fe. The total phenolic and anthocyanoside contents of Ulva lactuca were 2.69 mg/g and 0.13 mg/g, respectively. Cells treated with Ulva lactuca methanol extracts for 24 hours post UVB exposure increased cell viability in a concentration-dependent manner compared to the non-treated control. Also, Ulva lactuca methanol extracts decreased the levels of UVB-induced DNA damage such as cyclobutane pyrimidine dimer and DNA damage response (DDR) proteins such as p-p53 and p21. These results suggest that Ulva lactuca methanol extracts comprising physiological active substances such as Mg, polyphenols and anthocyanosides promote DNA repair by regulating genes related with DDR.

Carbon supports for dispersed platinum (Pt) electrocatalysts in direct methanol fuel cells (DMFCs) are being continuously developed to improve electrochemical performance and catalyst stability. However, carbon supports still require solutions to reduce costs and improve catalyst efficiency. In this study, we prepare well-dispersed Pt electrocatalysts by introducing titanium dioxide (TiO2) into biomass based nitrogen-doped carbon supports. In order to obtain optimized electrochemical performance, different amounts of TiO2 component are controlled by three types (Pt/TNC-2 wt%, Pt/TNC-4 wt%, and Pt/TNC-6 wt%). Especially, the anodic current density of Pt/TNC-4 wt% is 707.0 mA g−1 pt, which is about 1.65 times higher than that of commercial Pt/C (429.1 mA g−1 pt); Pt/TNC-4wt% also exhibits excellent catalytic stability, with a retention rate of 91 %. This novel support provides electrochemical performance improvement including several advantages of improved anodic current density and catalyst stability due to the well-dispersed Pt nanoparticles on the support by the introduction of TiO2 component and nitrogen doping in carbon. Therefore, Pt/TNC-4 wt% may be electrocatalyst a promising catalyst as an anode for high-performance DMFCs.

메탄올은 부동액, 세제, 살균제, 소독제 및 공업용매 등 다양한 분야에서 사용되는 독성 알코올이며, 섭취, 경피흡 수 및 흡입을 통해 인체에 노출된다. 체내에서 메탄올은 포름알데히드와 포름산으로 산화되며, 이러한 생성물을 대사산증, 시신경장애를 일으키고, 심한 경우 사망에 이르기도 한다. 본 연구에서는 국내에서 유통되는 세척제 및 헹 굼보조제 중 메탄올의 함량을 모니터링하고자 하였으며, 기존의 식약처에서 고시한 방법보다 더 간단하고 빠른 GCHS- MS방법으로 진행하였다. 본 분석법은SIM 모드로 진행하였고(메탄올 31 m/z 및 이소프로판올 45 m/z), LOD는 1.09 mg/kg으로 계산되었으며, 정확도와 정밀도는 각각 91.1-97.9%와 10%이하로 나타나 정량분석에 적합한 수준 임을 확인하였다. 본 연구는 세척제 중 메탄올 함량을 모니터링한 최초의 연구로써 가치가 있다고 판단된다.

In this study, a membrane electrode assembly(MEA) composed of three electrodes(anode, cathode, and reference electrode) is designed to investigate the effects of methanol concentration on the overpotentials of anode and cathode in direct methanol fuel cells(DMFCs). Using the three-electrode cell, in-situ analyses of the overpotentials are carried out during direct methanol fuel cell operation. It is demonstrated that the three-electrode cell can work effectively in transient state operating condition as well as in steady-state condition, and the anode and cathode exhibit different overpotential curves depending on the concentration of methanol used as fuel. Therefore, from the real-time separation of the anode and cathode overpotentials, it is possible to more clearly prove the methanol crossover effect, and it is expected that in-situ analysis using the three-electrode cell will provide an opportunity to obtain more diverse results in the area of fuel cell research.

치자 씨의 에틸 아세테이트, 증류수 및 70% 메탄올(v/v)의 3가지 용매를 사용한 추출물의 용매 별 플라보노이드 함량 및 항산화 활성, 금속 킬레이트 능력 측정을 통하여 치자의 기능성 식품 재료로서의 가치를 검토하기 위하여 본 실험을 수행하였다. 치자 씨의 탄닌 함량은 1.517±0.003 mg CE/g (mg of catechin equivalents) 건조 중량으로 나타났으며, 치자 씨 용매 별 추출 수율은 증류수 (36.61%), 70% 메탄올(30.10%), 에틸아세테이트(20.40%) 순으로 나타났다. 추출 용매 별 항산화 활성은 농도(0.2, 0.4, 0.6 mg/mL)가 증가할수록 유의적으로 증가하였으며(p<0.05), 양성대조구로 사용된 ascorbic acid, BHA, EDTA 보다 낮은 활성이 관찰되었다. 플라보노이드 함량(mg QE/g, mg of quercetin equivalents)은 70% 메탄올(0.799), 증류수(0.565), 에틸아세테이트(0.117) 순으로 관찰되었으며, 항산화 활성은 대부분의 분석에서 용매 별 플라보노이드 함량 순과 비슷한 양상으로 나타났지만 ABTS 라디칼 소거능과 SOD 유사활성은 증류수 추출물이 70% 메탄올 추출물의 항산화 활성 보다 높은 것으로 나타났다. 치자 씨의 각 용매별 수율과 항산화 활성을 비교하였을 때, 증류수와 70% 메탄올 용매를 사용하여 추출 이용하는 것이 바람직하다고 생각된다. 본 실험 결과 치자 씨는 플라보노이드 화합물을 다량 함유하고 있으며 그로 인한 높은 수준의 항산화 활성과 생리활성을 가지고 있어 기능성 식품 및 천연 항산화제로서의 가치가 매우 기대된다.

본 연구에서는 (주)파인텍에서 제조한 제올라이트 4A 분리막을 이용하여 물/메탄올, 물/부탄올 혼합물의 투과증발 실험을 수행하였다. 분리막을 투과한 기체분자들은 액체질소트랩을 이용하여 포집하였으며, 기체크로마토그래피(TCD)를 이 용하여 혼합물의 조성을 분석하였다. 실험을 통해 물과 메탄올(분리계수 최대 250 이상), 물과 부탄올(분리계수 최대 1,500 이상)의 혼합물에서 선택적으로 물을 분리하는 것을 확인하였다. GMS (generalized Maxwell Stefan) 이론을 적용하여 2성분 계의 투과증발 거동을 모사하였으며, 상수추정을 통하여 제올라이트 비지지체의 흡착상수 및 확산상수를 구하였다. 제올라이 트 4A 분리막의 경우 기공의 크기가 물보다는 크고, 메탄올, 부탄올 보다는 작기 때문에, 알코올로부터 물을 분리시키는 공정 에 적용시킬 수 있다. 바이오 에탄올 분리, 부탄올 분리, 막반응기, 하이브리드 반응-탈수 공정 등에 적용할 수 있을 것으로 사료된다.

이산화탄소를 이용한 메탄올 합성반응과정에서 생성되는 물, 메탄올, 부탄올로 이루어진 혼합용액에서 제올라이트 분리막을 이용하여 물을 분리시키기 위해 투과증발실험을 진행하였다. 투과증발실험에서 사용된 분리막은 ㈜파인텍에서 합성된 제올라이트 분리막을 공급받아 사용하였다. 투과증발실험에서는 물을 분리하는 성능을 확인하기 위해 가스크로마토그래피 등의 실험장비와 성능지표 를 나타내는 계산식들을 사용하였다. 실험을 통해 물과 메탄올(분리계수 최대 250 이상), 물과 부탄올(분리계수 최대 1500 이상)의 혼합물에서 선택적으로 물 을 분리하는 것을 확인하였다. GMS (Generalized Maxwell Stefan) 이론을 적용 하여 2성분계의 투과증발 거동을 모사하였으며, 상수추정(parameter estimation) 을 통하여 제올라이트 비지지체의 흡착상수 및 확산상수를 구하였다.

Acute and chronic toxicities of methyl ethyl ketone and methanol were investigated on Paronychiurus kimi (Collembola), for evaluating the potential effects of accidental exposures of these chemical substances on the terrestrial environments. This study was undertaken to establish a toxicity database for these chemical substances, which was required for the preparation of the response compensation and liability act for agricultural production and environmental damage. The 7-d acute toxicity and 28-d chronic toxicity were conducted using the OECD artificial soil spiked with varying, serially diluted concentrations of methyl ethyl ketone and methanol. Mortality was recorded after 7-d and 28-d of exposures, and the number of juveniles were determined after 28-d of exposure in the chronic toxicity test. In both assessments, methanol was more toxic than methyl ethyl ketone in terms of mortality (LC50) and reproduction (EC50). The 7-d LC50 of methyl ethyl ketone and methanol were 762 and 2378 mg kg-1 soil dry wt., respectively, and the 28-d LC50s were 6063 and 1857 mg kg-1 soil dry wt., respectively. The 28-d EC50 of methyl ethyl ketone and methanol were 265 and 602 mg kg-1 soil dry wt., respectively. Comparison of results obtained in this study with literature data revealed that P. kimi was more sensitive to methanol than other soil invertebrates. However, given the high volatility of the chemicals tested in this study, further studies are necessary to improve the current test guideline, or to develop new test guidelines for an accurate assessment of chemicals that require toxicity databases for chemical accidents.

In the present study, we investigated the protective effect of various grain methanolic extracts against UVB-induced photo-aging in human skin fibroblasts. Various grain methanolic extracts were evaluated for their antioxidant compounds and activities. 2,2-Ddiphenyl-1-picryhydrazyl radical (DPPH) and ABTS 2,2-azino-bris-(3-ethylbenzoth iazoline-6-sulphonic acid) radical cation scavenging activities have been used to measure the relative antioxidant activities of extracts from grains. The content of total polyphenolics in the extracts were evaluated using spectrophotometric methods. Human skin fibroblast (Hs68) cells were pretreated with various grain methanolic extracts (25 μg/mL). Skin toxicity was simulated by exposing the cells to UVB (30 mJ/cm2) irradiation. In response to the UVB-irradiation, an increased amount of matrix metalloproteinases (MMPs) release was observed, whereas pretreatment of various grain methanolic extracts significantly inhibited the production of MMP-1 in Hs68 cells. We also found that pretreatment of the extracts significantly decreased UVB-induced reactive oxygen species and significantly increased total collagen content in Hs68 cells. These results provide that grains could be regarded as a potential ingredient in natural cosmetics, used for UVB protection.

컴퓨터 시스템의 발전과 더불어 과학적 이론의 수식화와 체계화를 통해 고분자 소재의 물성을 예측할 수 있는 다양한 종류의 시스템이 개발되어 왔으며 실제 분자동력학 시뮬레이션을 이용한 고분자 소재의 물성예측은 다양한 분야에 적용되어 왔다. 본 연구에서는 탄화수소계 고분자인 술폰화폴리아릴렌이서술폰 계　고분자와 상용화된 폴리이서술폰, 폴리비닐리덴플로라이드 고분자 소재를 이용한 블렌드 막을 제조하였으며, 제조된 분리막의 함량변화에 따른 이온과 메 탄올 투과물성 변화 예측에 대한 연구를 진행하였으며, 실제 실험결과와 비교분 석을 진행하였다.

The effects of antioxidant measured by DPPH radical scavenger activity, the extract of harvestry in July shown highest activity(91.8±0.01%). The all extracts of 4 parts(leaf, f1ower, root, branch) of harvestry in July were shown better radical scavenger activity than BHT(89.2±0.01%). The antibacteria activity of Agrimonia pilosa extracts was determined by using a paper disc method against bacteria, the methanol extracts(70%) showed the most active antibacteria activity against 12 kinds of harmful microorganisms. The methanol extracts(70%) showed the highest antibacterial activity against S. aureus and B. subtilis. In addition, the minimum inhibitory concentration(MIC) of methanol extracts(70%) against S. aureus, B. subtilis, C. diphtheriae, S. mutans, and S. epidermidis were revealed 0.625~10mg/mL. As a result, antibacteria activity in methanol(70%) extract of Agrimonia pilosa shown higher gram positive bacteria than gram negative bacteria.

본 연구에서는 sol-gel 법을 이용하여 montorillorite가 가진 단점을 보완하기 위해 각기 다른 관능기를 가진 무기입자를 제조하였으며, sulfonated poly(arylene ether sulfone)에 입자를 첨가해 복합막을 제막하였다. 제조한 무기 입자의 관능기에 따라 복합막의 물성, 전기적 성능 등의 변화를 관찰하였으며, 이에 따라 최적화된 관능기를 찾는 연구를 진행하였다.

This study aimed to evaluate the efficacy of the antioxidative and antidiabetic activities of the flowers, leaves, and roots of the Jerusalem artichoke (Helianthus tuberosus L.). The total polyphenol and flavonoid contents of the leaves were higher than those of the flowers and roots. However, the DPPH radical-scavenging and hydroxyl radical-scavenging activities of the flowers were higher than those of the leaves and roots. The nitrite-scavenging ability under acidic conditions was high in Jerusalem artichoke flower extracts. The α-glucosidase inhibitory activity and α-amylase inhibitory activity of a methanol extract of Jerusalem artichoke roots were about 60% (5 mg/mL concentration). Based on these experiments, it can be concluded that the flowers leaves, and roots of the Jerusalem artichoke can be used as natural preservatives. Therefore, they can be developed as functional foods, to take advantage of their antioxidant activity and abundant polyphenols. This study suggests that the whole Jerusalem artichoke, including roots, leaves, and flowers, is useful as a functional, nutritious food product.

This research is to investigate the performance analysis of methanol fuel cell for flow channel with four different types of the channel (Serpentine I, II, Inter-digitated, Parallel) in the fuel cell stack. Velocity, pressure, temperature and density distributions of fluid over the flow domain of the flow channel are numerically calculated for the optimum design of flow channel with uniform inlet velocity. According to better water discharge and mutual gas reaction with low pressure drop and high density difference between inlet and outlet in the flow channel, Serpentine I type is of highest performance of the flow channel shapes in the present methanol fuel cell models.

This study was conducted to evaluate the neuroprotective effects of Cheonggukjang extract in in-vitro and in-vivo models. T98G-human glioblastoma cells were pretreated with various concentrations (1~10 mg/mL) of Cheonggukjang extract for 24 h and then exposed to H2O2 (1 mM) for 3 h. The neuroprotective effects of Cheonggukjang extract were measured using a CCK-8 kit assay, total antioxidant capacity (TAC) assay, reactive oxygen species (ROS) assay, and lactate dehydrogenase (LDH) release assay. The early stage focal ischemia rodent model was used as the in-vivo neurotoxicity model. Various concentrations (10~200 mg) of Cheonggukjang extract were administered to the animal models for 1 week. Peripheral blood was analyzed for glutathione peroxidase (GPx) expression by ELISA, and infarct volume reduction was analyzed by TTC staining. Cheonggukjang extract significantly (p<0.05) increased cell viability in T98G cells against H2O2 as well as against the induced neurotoxicity. Indeed, treatment with the Cheonggukjang extract induced a decrease in ROS and LDH expression and increased TAC significantly (p<0.05). However, Cheonggukjang extract did not induce a decrease in infarct volume or an increase in GPx expression in the in-vivo model. Despite the limitation in neuroprotection, Cheonggukjang extract may be useful for treating ROS injury.