Application of Subcritical Water Hydrolysate from Thermosetting Polyester Resin to Aqueous Agents

Thermosetting polyester resin used in fiber reinforced plastic (FRP) is very difficult to be recycled since it cannot be re-molded like thermoplastic resin. In recycling thermosetting polyester resin, subcritical water with alkali was applied to hydrolyze ester bonds to obtain styrene-fumaric acid copolymer (SFC). SFC, subcritical water hydrolysate from thermosetting polyester resin, has a molecular structure of functional polymer. Alkali salt of the SFC has a same molecular structure as alkali salt of styrene-maleic anhydride copolymer (SMA) which is widely used in various kinds of high performance additives for aqueous applications. In these applications, dispersing agent, detergent builder, and surface sizing agent were selected for application of alkali salt of the SFC . The reaction product liquid contains sodium salt of SFC (SFC-Na). It was evaluated as dispersing agent and detergent builder. Ammonium salt of SFC (SFC-NH4) was evaluated as surface sizing agent for paper. The evaluation results were compared with that of commercial additives to verify the possibility to substitute them. The reaction product liquid showed superior dispersing effect to commercial dispersing agent for hydrophobic powder. It also showed superior alkali buffering capacity to commercial detergent builder. SFC-NH4 showed higher sizing effect than commercial sizing agent

Utilization of Sub and Supercritical Water Reactions in Resource Recovery of Biomass Wastes

Recently, the utilization of sub and supercritical water has been proposed to recover waste substances from biomass. This is important not only for prevention of environmental issues, but also for rational utilization of natural resources. Sub and supercritical water treatment is one of the most effective methods for this, because water at high temperature and high pressure behaves as a reaction medium with remarkable properties. This sub and supercritical water treatment process can promote various reactions such as oxidation, hydrolysis, and dehydration. Therefore, sub and supercritical water can be used for the conversion of organic wastes to useful chemical compounds, as well as for oxidizing hazardous waste into CO2 or harmless compounds. This paper presents the concepts of sub and supercritical water and their application in organic waste recycling at temperatures of 423 - 673 K for substances such as lignin and its derived compounds

Effects of Z-Isomerization on the Bioavailability and Functionality of Carotenoids: A Review

Carotenoids, the most common fat-soluble plant pigments in nature, are beneficial to human health due to their strong antioxidant activities and abilities to prevent various diseases. Carotenoids have many geometrical isomers forms caused by E/Z-isomerization at arbitrary sites within the multiple conjugated double bonds. Several studies have addressed that the bioavailability as well as the antioxidant, anticancer, and antiatherosclerotic activities of carotenoids varies among the isomers. In addition, those variations differ among carotenoids: Z-isomerization resulted in “positive” or “negative” effect for carotenoids bioavailability and functionality, for example, Z-isomers of lycopene are more bioavailable than the all-E-isomer, whereas the opposite is observed for β-carotene. Thus, to efficiently promote the beneficial effects of carotenoids by ingestion, it is important to have a good understanding of the impact of E/Z-isomerization on the corresponding functional changes. The objective of this contribution is to review the effects of carotenoid Z-isomerization on bioavailability and functionality and describe their differences among carotenoids

Supercritical Fluids Extraction of Valuable Compounds from Algae: Future Perspectives and Challenges

Algae (macro and micro) can be used to produce several high–value metabolites to supply industries as cosmetics, additives and pigments, among others. Those metabolites can have physiological and nutritional benefits for human and animal health. However, the availability of high–value metabolites from algae is still unaffordable due to traditional extraction techniques and their requirements of energy and use of pollutant solvents. Recently, green extraction technologies for the extraction of high–value metabolites have become more desirable due to their sustainability and environmental benefits. Supercritical fluids extraction, as green extraction techniques, has been widely applied for extraction of high–value metabolites from algae. Here, the highlight of supercritical CO2 and subcritical water on the extraction of bioactive compounds from macro– and microalgae was presented. The perspective and challenge for using supercritical CO2 and subcritical water on the algae extraction were also concluded

Comparison of Conventional and Ultrasound Assisted Supercritical Carbon Dioxide Extraction of Curcumin from Turmeric (Curcuma longa L.)

Recently, ultrasound assisted supercritical fluid is used for extraction the valuable compounds from a number of plant materials as an alternative to conventional method because it can enhance the extraction rate and yield. Curcumin is an important component of turmeric (Curcuma longa L.) with many useful functions to human health. The objective of this study is using ultrasonic assisted supercritical carbon dioxide (USC-CO2) to extract curcumin from turmeric and compared to conventional method. The effect of operating conditions on extraction, including temperature (40 - 60oC), pressure (15 - 25 MPa), extraction time (30 - 120 min), CO2 flow rate (2 - 4 mL/min) and percentage of cosolvent (10 - 20% v/v) were also studied. The result shows that the high extraction yield of 7.17% w/w and curcumin content of 1.69% w/w were achieved at temperature of 50oC, pressure of 25 MPa, extraction time of 90 min, CO2 flow rate of 3 mL/min with 10% cosolvent. Compared to conventional method, USC-CO2 could provide higher curcumin content in extraction yield in a shorter extraction time. Scanning electron microscopy (SEM), thermal gravity (TG), and fourier transform infrared spectroscopy (FTIR) was used to analyse turmeric undergoing USC-CO2 and conventional extraction and showed that ultrasound could break down the cell walls and remove some functional groups from plant materials, resulting an increase the selectivity of compounds in extraction yield

ケンリノウリョク ナキ シャダンロン ノ ゲンザイ ドイツミンポウテン セイテイカテイ ニ オケル ギロン ノ サイヒョウカ

多胡圭一教授國井和郎教授退官記念