Self-cleaning and photocatalytic TiO2 thin films were prepared by a facile sol-gel method followed by spin coating using peroxo titanic acid as a precursor. The as-prepared thin films were heated at low temperature(110 °C) and high temperature (400 °C). Thin films were characterized by X-ray diffraction(XRD), Field-emission scanning electron microscopy(FESEM), UVVisible spectroscopy and water contact angle measurement. XRD analysis confirms the low crystallinity of thin films prepared at low temperature, while crystalline anatase phase was found the for high temperature thin film. The photocatalytic activity of thin films was studied by the photocatalytic degradation of methylene blue dye solution. Self-cleaning and photocatalytic performance of both low and high temperature thin films were compared.
HIV/AIDS is an important global issue in human rights and health. The United Nations Refugee Convention clearly addresses to guarantee healthcare rights to refugees at the same level as those provided to citizens. In Korea, the number of refugee applicants has surged since the enactment of the Refugee Act in 2012. Regarding human dignity and human rights, however, there are serious concerns that Korea’s healthcare laws and policies would not fully protect the right of foreigners who are suffering from financial hardship. This paper proposes the ways to improve healthcare equity by comparing the UNAIDS Guidelines to Korean policies on HIV-positive refugee applicants.
The tension of warp from trawler and sea-floor contact can generate tilt and wake turbulence around otter boards. Preliminary measurements of otter board tilt and 3-D flow velocity during bottom trawl operations were taken using a vector instrument to investigate the effects of wake turbulence at the trailing edge of the otter board. Tilt data (i.e., yaw, pitch, and roll) at 1 Hz and flow data (velocities in the towing, lateral, and vertical directions) at 16 Hz were analyzed to determine their periods and amplitudes using global wavelet and peak event analyses. The mean period (±standard deviation) of the tilt from the peak event analysis (5±2 s) was longer or double than that of flow velocity (3±2 s). The two periods also had a significant linear relationship. The turbulence rate of flow was 30-50% at the trailing edge and was closely related to roll deviation. The frequency of phase difference ratios (i.e., peak time differences between tilts and flow periods) was significantly different from random occurrence in two trials, possibly due to side tidal effects. However, in the other trials, flow peaks were random, as shown by the even peak times between tilts and flows. Future studies should focus on reducing tilt variation, wake turbulence, and bottom contact to stabilize otter board motion.
Starch is an abundant, renewable, and low cost material that has been extensively studied for its role in crystallization. Herein, we developed a facile and green approach to produce the starch-based microparticles (SMPs) that could encapsulate curcumin during the self-association of short glucan chain obtained from waxy maize starch. Scanning electron microscopy (SEM) analysis indicated that the diameters of curcumin-loaded SMPs were ranged from 1.5 μm to 3 μm. The characteristics of the curcumin-loaded SMPs were evaluated via Raman spectroscopy, confocal microscopy, UV spectrophotometer, and X-ray diffraction (XRD). The results showed that the suspended curcumin was encapsulated in SMPs in amorphous form with a encapsulating efficiency of about 96.36%. Photostability test confirmed that curcumin that is loaded inside SMPs was effectively protected against the photodegradation. Curcumin-loaded SMPs can be used not only in food industry for extending the shelf life of curcumin, but also in pharmaceutical industry to design effective carrier for oral delivery.
Previous studies demonstrated that rice bran oil has an anti-inflammatory effect. The current study investigated if the immune responses and energy metabolism phenotypes were affected by rice bran oil. Rice bran oil and palm oil, which served as an experimental control, were treated to RAW 264.7 macrophages respectively, followed by LPS stimulation so as to quantify the production of pro-inflammatory cytokines such as IL-6 and TNF-α. The expression of surface markers i.e. CD 80, CD 86 and MHC-classⅡ and mitochondrial metabolism phenotypes were also tested.
The data exhibited rice bran oil suppressed inflammatory responses and mitochondrial metabolism were modulated by rice bran oil. These results warrant the necessity for the compositional and/or mechanistic studies to elucidate the details.
Vitamin A is essential for growth and differentiation of a number of cells and tissues, as result the precursor, a carotenoid β-carotene remains their essential source of vitamin A. However, the major problem this carotenoid face, is its susceptible to photodegradation and chemical oxidation, those properties make it difficult to use as an ingredient as functional food product and reduce its bioavailability. This study presents a novel approach to prepare a one-step inclusion complex using amylose microparticles as host molecule using amylosucrase from Deinococcus geothermalis (DGAS) and β-carotene nanoparticles, which were added into the DGAS enzyme reaction solution to entrap them during the synthesis of amylose chains. HRFE-SEM showing a spherical shape and average diameter of 4-8 μm; XRD and DSC showed an amorphous structure as well as less energy required to start the gelatinization process, due to the complexation of amylose chains with the β-carotene nano dispersion. Last but not least Raman spectroscopy was performed in order to confirmed the complex formation between β-carotene and amylose microparticles, showing the characteristic peaks of both compound. The stability test in this study showed the high stability of the complexed microparticles against environmental stresses such as, photodegradation and chemical oxidation. We expect this study contributes to the development of functional food materials to enhance the stability and bioavailability of active compounds.
Ionic liquid (IL), asymmetric chemical consist of bulky cations and tiny-mobile anions, has been known as promising DNA extraction, separation and preservation agent due to its strong interaction with DNA. However, the interaction underlying DNA-IL complex forming mechanism remains to be elucidated. Herein, we employed three types of ILs (EMIM-Cl, BMIM-Cl, and OMIM-Cl) to investigate the changes of DNA morphology upon the alkyl chain length of ILs by using solid-state nanopore technology combining with atomic force microscopy (AFM). The results of AFM show the different forms of DNA, including aggregate, stretching, and bundling shapes in terms of EMIM-Cl, BMIM-Cl, and OMIM-Cl, respectively, assuming that the shape of DNA-IL complexes is responding to the alkyl chain length of ILs. In DNA translocation experiment. From the alteration of blockade current signals during the DNA pass through the nanopore, we estimate that the shapes of DNA are changed due to the treatment with BMIM-Cl, and OMIM-Cl, which not only increased the blockade current signals about 2-4 times in the case of OMIM, but also decrease the event showing translocation of DNA folding, implying that the alkyl chain affect to DNA stretching and bundling. The results indicate the length of hydrophobic alkyl group of IL plays an important role in determination of DNA morphology, providing their further application in nanopore technique for slowing DNA translocation speed toward discovering protein-DNA interaction or DNA sequencing.
Due to the globalization of food supply have been growing, there have been a great demands for food safety and quality assuarance for on-site detection. On-site detetction isuue is the process should be fast, simple, user-friendly and require minimal equipments. Herein, we developed a Radial chromatography (RC) biosensor integrated with the immuno-gold nanoparticles-coated magnetic nanoparticle (AuNPs@Fe3O4) for specific separation and detection of the target bacteria, E. coli O157:H7, in sample. The immuno-AuNPs@Fe3O4 specifically binds to E.coli O157:H7 creating AuNP@Fe3O4-E.coli complexes and captured bacteria were concentrated by magnet. The complex can be identified with inner ring derived from the difference of mobility of free AuNPs@Fe3O4 on the RC sensor. Our results show that AuNPs@Fe3O4 based RC sensor has high sensitivity to the target bacteria over non-target bacteria with a detection limit of 103 CFU/ml. Our system offers a rapid and sensitive means of detecting E.coli O157:H7 with naked eyes, which can be applied to the field diagnosis.
Rapid, simple, and sensitive detection of pathogen bacteria is a highly topical research area due to increasingly concerning of food safety and public health. Surface-enhanced Raman spectroscopy (SERS) is a promising and attractive technique offering fast, sensitive, comparatively low-cost, and in-suit detection of pathogenic bacteria. However, this technique requires the preparation step for reducing the noise derived from heterogeneous matrixes of food sample. Immunomagnetic separation (IMS) is widely used technique enabling separation and concentration of the target analyte. It can be used not only laboratory scale but also field diagnosis easily. Here, we synthesized gold-shelled starch magnetic microparticles (GS@SMMPs) for effective separation and concentration of Escherichia coli O157:H7, which were subsequently subjected to SERS integrated with gold-coated 3D-well substrate for bacterial detection in aqueous solution. GS@SMMPs were labelled by Anti-E. coli O157 monoclonal antibody through gold binding protein and staphylococcal protein G (GBP-SPG) fusion protein. In IMS experiment, the immuno-GS@SMMPs showed high capture efficiency over 90% to E. coli O157:H7, which resulted in 10 times decrease in detection limit in PCR assay. Through SERS assay, E. coli O157:H7 concentrated by immuno-GS@SMMPs were successfully detected even at an extremely low concentration of 101 CFU/ml the subjected to SERS. Moreover, by using sandwich method using SERS reporter consisting of GBP-SPG, we found that E. coli O157:H7 were able to be detected by SERS quantitatively through measuring the SERS intensity of GBP-SPG. This novel strategy combining SERS and IMS could be meaningful for extending the application in SERS for in-suit sensitive detection of pathogenic bacteria.
The objective of this study was to determine the effect of moisture contents (40, 50, 60%) and CO2 gas injection (0 and 800 mL/min) on physicochemical properties of extruded soy protein isolate (SPI). The expansion ratio and specific length at 40 and 50% moisture contents with CO2 gas injection increased while piece density decreased. On the contrary, the expansion ratio and specific length of extruded SPI at 60% moisture content with CO₂ gas injection decreased while piece density increased. Extruded SPI with CO2 gas injection had small cell size and higher amount of cell than extruded SPI without CO2 gas injection. The water holding capacity and nitrogen solubility index increased with CO2 gas injection increased while the integrity index and the springiness and cohesiveness decreased. In conclusion, extruded SPI with CO2 gas injection showed better expansion properties and cell formation than extruded SPI without CO2 gas injection.
The purpose of this study was to utilize the stem of Opuntia ficus-indica and to optimize the extraction conditions and standardize extract process for water soluble dietary fiber and solid. Extraction process was optimized by applying various conditions such as pH, ethanol concentration, extracting temperature and time. Maximum extraction yield for water soluble dietary fiber and solid were obtained using 100% water, indicating that ethanol hampered extraction. Also, extraction was unstable with higher heat, longer extraction time, and low acidic conditions. Maximum extraction of water soluble dietary fiber (27.92%) and solid (5.6 g) were obtained at 50°C, pH7, and 7 hr extraction time. Extract had antioxidant capacity at 1105.98 mg vitamin C equivalents (VCE) on ABTS assay and 118.10 mg VCE on DPPH assay.
Physicochemical characteristics of vinegar pickled cabbages during storage were examined. 3x3 cm cube-shaped stems and leaves of cabbages examined in different pickling condition (salt 2, 4, 6, 8% and sugar 5, 10, 15, 20% brix) for 12 hours, and salt and sugar penetration rate were measured at every 2 hours. The vinegar pickled cabbages were stored for 4 weeks at 3 different temperature conditions (5, 15, and 25℃), and sensory test and TPA test were performed at intervals of every week. The rates of salt and sugar penetration were faster on the leaves than on the stem of cabbage. Also, increase in salt and sugar concentration of solutions led to increase in salt and sugar permeation rate. As a result of sensory test, both leaves and stems of cabbages stored at 5℃ did not show any significant difference with storage time. However, preference degree of cabbages stored at 15 and 25℃ decreased significantly as increasing the storage time. Hardness and cohesiveness of pickled cabbage were increased significantly as the storage time increased, but storage temperature did not give any effect on them.
Curcumin is an active polyphenolic compound with antioxidant, anti-inflammatory and antitumor properties. Curcumin, however, is highly unstable under physiological conditions due to its low stability in acidic and alkaline conditions. Therefore, the objective of this study was to investigate the effects of enzyme-treated rice starch as a wall material on the stability of curcumin in oil-in-water emulsion under different pH conditions. The rice starch was treated using 4-a-glucanotransferase for different time periods and their molecular weight distribution was measured by HPSEC. Curcumin was encapsulated within lipid droplets of O/W emulsion prepared with Tween 20 and the modified rice starch in the aqueous phase at different concentrations (0, 2.5, 7.5 and 10 wt%). The temperature and pH stability of the system were determined respectively by measuring particle size, zeta potential and retention of the curcumin loaded in the emulsion after one-week storage in the solutions with different pH and temperature conditions. The average molecular weight of the modified starch decreased with treatment time. The 96h treated rice starch had the lowest molecular weight while the 1h treated starch mainly consisted of high molecular weight components. The storage temperature did not significantly influence the stability of curcumin emulsion. However, the particle size of the emulsion with modified starch slightly increased when stored at acidic pH condition, which might be attributed to starch aggregation. The curcumin retention was higher for the samples with the modified starch than the control at all concentrations. The pH stability of the curcumin was also higher than the control at all pH conditions. Specifically, the 1h treated starch showed the best performance regarding curcumin protection in emulsion, which might be attributed to the high viscosity that retarded the curcumin release. Further research needs to be conducted on the mechanism.
Licorice and rosemary contain a number of natural phenolic compounds which have a strong antibacterial and antioxidant activity. Ulleungdo stonecrop (US, scientific name: Sedum takesimense Nakai), indigenous island, is also known as a good antibiotic agent and skin whitening agent and is regarded as a promising materials in cosmetics field. Although the antibacterial activity of each material have been reported, little is known about the effect of using them together. Therefore, the purpose of this study was to investigate the synergistic effect on antibacterial activity when licorice and rosemary extract and US were used together. Since licorice and rosemary are lipid soluble materials and US is water soluble material, oil in water (O/W) emulsion system was used for this study. To manufacture O/W emulsions containing three kinds materials, first licorice and rosemary extracts and US was dispersed in soy bean oil and phosphate buffer (pH7) respectively. Decaglyceryl laurate was used as an emulsifier. There was slight decrease (-0.09~-0.46 Δlog) in the number of bacteria when O/W emulsion containing 300ppm of each licorice and rosemary extracts was mixed into B.subtilis. However, adding US (2,700ppm) into aqueous phase caused the rapid decrease in the amount of bacteria to -1.71 ~ -2.96 Δlog which were much higher decrement than US only in normal emulsion (-1.64 Δlog). In particular, there was a noticeable synergistic effect when rosemary extract and US was used together. The results obtained from this study could provide useful information for utilizing licorice and rosemary extracts and US as functional materials in the food and cosmetic areas.
Response Surface Methodology (RSM) is a widely used statistical analysis for finding an optimal point of a response variable (dependent variable) in accordance with multiple explanatory variables (independent variable). We have previously used RSM to identify optimal temperature and humidity (represented by the amount of water spray) of the fresh forage system for maximizing the growth of barley after 6 days of seeding. Consequently, RSM demonstrated that the optimal growth condition of barley was 19.70 and 1.38 l/h. However, it was not proved by empirical result, we aimed to verify the RSM result through comparative experiments. Experiments were designed four trials with different conditions. The first trial represented optimal conditions obtained from RSM, i.e., 20 and 1.4(l/h), while the rest of trials represented; 1) 20 and 1.8(l/h), 2) 18 and 1.4(l/h), and 3) 23 and 1.4(l/h). After 6 days of seeding, the average barley weight of the first trial was 11,094 g which was the highest yield compared to other trials (10,101 g, 9,757 g, and 10,233 g). This result supports that the RSM successfully predicted the optimal growth condition to be applied for the fresh forage system.