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.

Chitosan powder is synthesized by a deasetylation process of chitin, obtained from processing of dried shrimp shell powder. Subsequently, chitosan (CS) membranes filled by montmorillonite (MMT) particles and phosphotungstic acid are prepared, and characterized by FT-IR and SEM. The morphology, obtained by SEM for the composite membrane, showed that MMT filler is successfully incorporated and relatively well dispersed in the chitosan polymer matrix. Water and methanol uptake for the CS/MMT composite membranes decrease with increasing MMT loadings, but IEC value increases. In all prepared CS/ MMT composite membranes, the CS membrane filled by 5 wt% MMT particles exhibits the best proton conductivity, while that with 10 wt% MMT loading exhibits the lowest methanol permeability; these values are 2.67 mS·cm−1 and 3.40 × 10−7 cm2·s−1, respectively. The best membrane selectivity is shown in the CS/MMT10 composite membrane; this shows that 10 wt% filled MMT is the optimum loading to improve the performance of the chitosan composite membrane. These characteristics make the developed chitosan composite membranes a promising electrolyte for direct methanol fuel cell (DMFC) application.

Asarum sieboldii Miq. (Aristolochiaceae) is a perennial herbaceous plant and has been used as traditional medicine for treating diseases, cold, fever, phlegm, allergies, chronic gastritis, and acute toothaches. Also, it has various biological activities, such as antiallergic, antiinflammatory, antinociceptive, and antifungal. However, the anticancer effect of A. sieboldii have been rarely reported, except anticancer effect on lung cancer cell (A549) of water extracts of A. sieboldii . This study investigated the anticancer activity of methanol extracts of A. sieboldii (MeAS) and the underlying mechanism in human FaDu hypopharyngeal squamous carcinoma cells. MeAS inhibited FaDu cells grown dose-dependently without affecting normal cells (L929), as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyl tetrazolium bromide and live and dead assay. In addition, concentration of MeAS without cytotoxicity (0.05 and 0.1 mg/mL) inhibited migration and colony formation. Moreover, MeAS treatment significantly induced apoptosis through the proteolytic cleavage of caspase-3, -7, -9, poly (ADP-ribose) polymerase, and downregulation of Bcl-2 and upregulation of Bax in FaDu cells, as determined by fluorescence-activated cell sorting analysis, 4`6-diamidino- 2-phenylindole stain, and western blotting. Altogether, these results suggest that MeAS exhibits strong anticancer effects by suppressing the growth of oral cancer cells and the migration and colony formation via caspase- and mitochondrial-dependent apoptotic pathways in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, MeAS can serve as a natural chemotherapeutic for human oral cancer.

In this study, graphene was rapidly grown by chemical vapor deposition using a liquid cell for supplying methanol as a carbon source of graphene. To realize the rapid growth, methanol which is carbon-contained organic solvent was used instead of methane gas, a widely used carbon source for graphene growth. The graphene grown with the growth time as a variable was transferred to a SiO2/ Si substrate with an oxide thickness of 300 nm to confirm whether it was grown with full coverage with an optical microscope. The results confirmed a full coverage in 0.5 min of growth. The Raman spectra also confirmed the G-peak position at 1585.0 cm−1 and an intensity ratio of 2D/G at 2.3 or higher. Concerning electrical transport characteristics, at an induced carrier density of 1 × 1012 cm−2, the hole (μh) and electron (μe) mobilities were 1524 cm2 V−1 s−1 and 1528 cm2 V−1 s−1, respectively. Thus, our study confirmed that high-quality, large-area graphene can be grown within 0.5 min.

In the current work, we have developed a new composite catalyst for methanol oxidation based on Ni and/or NiO incorporated in activated carbon (AC) derived from agricultural wastes (Rice straw). The new electrocatalysts based on nickel-activated carbon (Ni/AC) and nickel oxide-activated carbon (NiO/AC) composites were prepared by electroless plating technique. Physico-chemical characteristics of the composites such as structure, composition and morphology were studied by X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and particle size analyzer. The electrochemical activity of the prepared composites towards methanol electrooxidation reaction (MOR) has been evaluated under alkaline conditions by cyclic voltammetry, linear sweep voltammetry, and chronoamperometry. Among the examined electrodes, the electrochemical performance of NiO/AC preceded either Ni/ AC or Ni free AC and showed better stability. The dispersion of different forms of Ni in activated carbon in case of NiO/AC electrode is predicted to give rise to the increase in electrocatalytic activity in the potential range under study and makes it more resistant to poisoning by the byproduct of methanol oxidation. The effect of changing methanol concentrations and scan rates on the electrochemical characteristics of the modified electrode was studied and it was found that the diffusion process is controlled by methanol rather than OH− ions.

Deionized water, methanol, and ethanol were investigated for their effectiveness at dissolving LiCl-KCl-UCl3 at 25, 35, and 50℃ using inductively coupled plasma mass spectrometry (ICP-MS) to study the concentration evolution of uranium and mass ratio evolutions of lithium and potassium in these solvents. A visualization experiment of the dissolution of the ternary salt in solvents was performed at 25℃ for 2 min to gain further understanding of the reactions. Aforementioned solvents were evaluated for their performance on removing the adhered ternary salt from uranium dendrites that were electrochemically separated in a molten LiCl-KCl-UCl3 electrolyte (500℃) using scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Findings indicate that deionized water is best suited for dissolving the ternary salt and removing adhered salt from electrodeposits. The maximum uranium concentrations detected in deionized water, methanol, and ethanol for the different temperature conditions were 8.33, 5.67, 2.79 μg·L-1 for 25℃, 10.62, 5.73, 2.50 μg·L-1 for 35℃, and 11.55, 6.75, and 4.73 μg·L-1 for 50℃. ICP-MS analysis indicates that ethanol did not take up any KCl during dissolutions investigated. SEM-EDS analysis of ethanol washed uranium dendrites confirmed that KCl was still adhered to the surface. Saturation criteria is also proposed and utilized to approximate the state of saturation of the solvents used in the dissolution trials.

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.

Ficus carica L. (fig ) is one of the first cultivated crops and is as old as humans. This plant has been extensively used as a traditional medicine for treating diseases, such as cough, indigestion, nutritional anemia, and tuberculosis. However, the physiological activity of fig leaves on oral cancer is as yet unknown. In this study, we investigated the anticancer effect of methanol extracts of Ficus carica (MeFC) and the mechanism of cell death in human FaDu hypopharyngeal squamous carcinoma cells. MeFC decreased the viability of oral cancer (FaDu) cells but did not affect the viability of normal (L929) cells, as determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay and Live and Dead assay. In addition, MeFC induced apoptosis through the proteolytic cleavage of procaspase-3, -9, poly (ADP-ribose) polymerase (PARP), downregulation of Bcl-2, and upregulation of Bax, as determined by 4′,6-diamidino-2-phenylindole dihydrochloride staining and western blot analysis. Moreover, a concentration of MeFC without cytotoxicity (0.25 mg/mL) significantly suppressed colony formation, a hallmark of cancer development, and completely inhibited the colony formation at 1 mg/mL. Collectively, these results suggest that MeFC exhibits a potent anticancer effect by suppressing the growth of oral cancer cells and colony formation via caspase- and mitochondrial-dependent apoptotic pathways in FaDu human hypopharyngeal squamous carcinoma cells. Therefore, the methanol extract of Ficus carcica leaves provide a natural chemotherapeutic drug for human oral cancer.

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.