The physiological activities of solvent fractions derived from the celtus methanol extract were measured. Following the extraction of celtus with methanol, the yields of the resulting fractions—methanol, hexane, chloroform, ethyl acetate, butanol, and water—were found to be 19.57%, 3.24%, 26.02%, 8.15%, 8.72%, and 63.57%, respectively. The total flavonoid contents of the celtus methanol extract were 13.76, 4.96, 8.20, 31.99, 28.33, and 5.02 mg CE/g, respectively. The DPPH radical scavenging activity (IC50%) was measured at 22.48, 6.14, 11.15, 24.20, 19.18, and 20.71 μg/mL, with the highest activity observed in the ethyl acetate layer. The hydroxyl radical scavenging activity (IC50%) results were 14.27, 2.97, 9.19, 13.93, 3.90, and 3.10 μg/mL, also showing the highest activity in the ethyl acetate layer. The SOD-like activity measurements for the solvent fractions yielded values of 22.07, 9.65, 16.24, 32.63, 39.64, and 32.76 units/mL, with the highest activity in the butanol layer. The α-glucosidase inhibitory activity results were 16.42%, 11.29%, 16.60%, 27.40%, 2.86%, and 36.19%. Correlation analysis of antioxidant components and antioxidant activity indicated a very high correlation between total flavonoid content and both DPPH and SOD-like activities, suggesting that the celtus methanol extract positively influences antioxidant activity.
In the pursuit of achieving in-situ real-time detection of methanol production rate during the photocatalytic reduction of CO2, we developed a methanol sensor using a copolymer-coated fiber Bragg gratings. The theoretical model of methanol measurement by sensor was established. The effect of methanol-selective sensitive material and its thickness on the performance of the sensor were investigated. Humidity and temperature interference to sensor measurements was compensated. Furthermore, TiO2 photocatalyst was prepared and the photocatalytic reactor was constructed. The methanol production rate in the photocatalytic CO2 reduction process was monitored by the prepared sensor in-situ. The results highlight that the fiber Bragg grating methanol sensor with 600 nm-thick poly(N-isopropylacrylamide)/polymethyl-methacrylate coating showed a high sensitivity, lower limit of detection, fast response and recovery speed, and high selectivity. The methanol generation rate of TiO2 photocatalytic reduction of CO2 measured by gas chromatograph and prepared fiber Bragg grating methanol sensor was 1.42 and 1.53 μmol/g-cat·h, respectively, the error of the two detection methods was 7.86%. This highlights the efficacy of the developed fiber Bragg grating methanol sensor for real-time in-situ detection of the methanol production rate during the photocatalytic reduction of CO2.
본 연구에서는 ALOHA와 Bow-tie를 활용하여 메탄올 추진 선박의 저장 탱크가 울산항에서의 누출 시나리오를 가정하여 위험도 평가하였다. ALOHA를 이용하여 대안 및 최악의 시나리오를 산정하여 피해 범위를 예측하였다. 독성 영향 범위의 결과(ERPG-2 기준)로는 대안(629m), 최악(817m)로 육상 탱크 터미널의 부두 시설 및 거주 지역까지 포함되는 것으로 확인되었다. 인화성 영향 범위(LEL 10% 기준) 는 대안(126m), 최악(218m) 선박에서만 발생하였으며, 열복사 영향 범위(5.0kW/m2 기준)는 대안(56m), 최악(56m)로 선박에서만 영향을 미쳤 다. 또한, 전문가 집단을 구성하여 Bow-tie 기법을 통하여 예방 대책과 완화 대책을 평가하였다. 대책 유형 분류에서는 Hardware와 Human 으로 구분되었으며, 안전 유효성과 위험 심각성의 결과에서는 “Gas Freeing System”, “Ventilation System”, “Fire-Fighting System이 가장 높은 평가를 받았다. 위의 평가를 토대로 위험도 평가를 도식화하였다.
본 연구에서는 온실가스 배출을 감축하기 위해 메탄올을 추진 연료로 사용하는 선박에 수소 연료전지 시스템이 추가된 하 이브리드 시스템 공정을 설계하였다. Case1에서는 메탄올 연료 엔진 시스템을 설계하여, 엔진에 가솔린 대신 메탄올을 연료로 공급했 을 때의 배기가스 배출량을 알아보았다. Case2에서는 Case1에 메탄올 개질 시스템을 추가해, 수소연료전지 시스템을 설계하였다. 이 하 이브리드 시스템에서는 그레이 수소를 생산하며, 엔진과 연료전지의 출력을 조합하여 선박을 구동한다. 하지만 그레이 수소는 수소를 생산하는 과정에서 탄소를 배출한다는 단점이 있다. 이 점을 보안하기 위해 Case3에서는 CCU시스템을 추가하였다. Case2에서 배출한 Flue gas의 이산화탄소를 포집한 후, 그레이 수소와 합성해 블루 메탄올을 생산하였다. 본 연구에서는 Case study를 통해 개질 온도22 0℃, 개질 압력500kPa, SCR은 1.0, flow ratio가 0.7일 때 최적의 운전조건임을 알 수 있었다. Case3의 시스템은 Case1에 비해 탄소 배출량 을 42% 감소시켰다. 결과적으로, Case3의 하이브리드 시스템을 통해 선박의 이산화탄소 배출을 유의미하게 저감할 수 있을 것으로 예 상한다.
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.
Taxillus yadoriki (Siebold) Dancer is a parasitic plant that grows on camellia trees and is common on Jeju Island. The branches of T. yadoriki have long been used to treat various diseases, including hypertension, diabetes mellitus, viral infections, and arthritis. Although recent studies reported that T. yadoriki has anticancer effects in various human cancer cell lines, including lung cancer, the exact molecular mechanisms supporting its anticancer effects are not well understood. This study aims to assess the anticancer effect of the methanol extract of T. yadoriki branches (METY) on mucoepidermoid carcinoma (MEC) cell lines (MC3 cells and YD15 cells) and explore its mechanism of action. Inhibitory activity of MEC cell proliferation was assessed using the CCK-8 assay. The mechanism of the anticancer effect on METY-treated MC3 cells and YD15 cells was evaluated with Hoechst 33342 stain and Western blot. After treating MC3 cells and YD15 cells with METY for 48 hours, the cytotoxicity of MC3 and YD15 cells increased, and nuclear fragmentation increased in both METY-treated MEC cells. Caspase-3 and cleaved PARP activation demonstrated apoptosis of METY-treated MEC cells. Cell proliferation inhibition with METY was alleviated in METY-treated MEC cells pretreated with zVAD-FMK, supporting the cell proliferation inhibition effect by apoptosis. METY-induced apoptosis in MEC cells occurs through MAP kinase pathways such as p38 and pAkt. MEC cell. METY-induced apoptosis of MEC cells occurs via the p38 and pAkt MAPK pathways. Therefore, METY may be a promising anticancer candidate for the MEC therapeutic strategy.
Humulus japonicus (HJ) is a widely used herbal medicine for pulmonary tuberculosis, hypertension, leprosy, and venomous wounds in Asia, particularly in China. Although HJ has certain physiological activities, such as longitudinal bone growth, antioxidation and alleviation of rheumatism, its anticancer activities, other than in colorectal and ovarian cancer, are yet to be studied. In this study, we investigated the anti-cancer activity and mechanism of methanol extracts of HJ (MeHJ) against human FaDu hypopharyngeal squamous carcinoma cells. MeHJ suppressed FaDu cell viability without affecting normal cells (L929), which was demonstrated using the MTT and Live & Dead assays. Furthermore, MeHJ effectively inhibited colony formation of FaDu cells, even at non-cytotoxic concentrations, and significantly induced apoptosis through the proteolytic cleavage of caspase-9, -3, -7, poly (ADP-ribose) polymerase and through the downregulation of BCL-2 and upregulation of BAX in FaDu cells, as determined by DAPI staining, flow cytometry, and western blot analyses. Collectively, these findings suggest that the inhibitory effects of MeHJ on the growth and colony formation of oral cancer cells may be mediated by caspase- and mitochondrial-dependent apoptotic pathways in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, MeHJ has the potential to be used as a natural chemotherapeutic drug against human oral cancer.