Showing papers by "Motonobu Goto published in 2014"

Extraction of Fucoxanthin from Raw Macroalgae excluding Drying and Cell Wall Disruption by Liquefied Dimethyl Ether

Abstract: Macroalgae are one of potential sources for carotenoids, such as fucoxanthin, which are consumed by humans and animals. This carotenoid has been applied in both the pharmaceutical and food industries. In this study, extraction of fucoxanthin from wet brown seaweed Undaria pinnatifida (water content was 93.2%) was carried out with a simple method using liquefied dimethyl ether (DME) as an extractant in semi-continuous flow-type system. The extraction temperature and absolute pressure were 25 °C and 0.59 MPa, respectively. The liquefied DME was passed through the extractor that filled by U. pinnatifida at different time intervals. The time of experiment was only 43 min. The amount of fucoxanthin could approach to 390 μg/g dry of wet U. pinnatifida when the amount of DME used was 286 g. Compared with ethanol Soxhlet and supercritical CO2 extraction, which includes drying and cell disruption, the result was quite high. Thus, DME extraction process appears to be a good method for fucoxanthin recovery from U. pinnatifida with improved yields.

Formation of PVP hollow fibers by electrospinning in one-step process at sub and supercritical CO2

Abstract: It was well known that electrospinning is one of the simple technical methods for the production of polymer nanoparticles and nanofibers. Various polymers have been successfully electrospun into ultrafine particles and fibers in recent years mostly in solvent solution and some in melt form. In this work, hollow fibers with walls made of organic polymer composites have been formed by electrospinning in a single processing step under pressurized carbon dioxide (CO2). The experiments were conducted at 313 K and ∼8 MPa. The capability and feasibility of this technique was demonstrated by the production of polyvinylpyrrolidone (PVP) fibers whose size and wall thickness could be independently varied by controlling a set of experimental parameters. The PVP fibers had an average pore diameter 2–4 μm. At low pressures (

Hot compressed water extraction of polysaccharides from Ganoderma lucidum using a semibatch reactor

Abstract: Ganoderma lucidum (G. lucidum) is a mushroom-forming white rot fungus. Although not edible, it is grown commercially for use as a medicinal supplement. In this study, G. lucidum was utilized for the extraction of polysaccharides by hot compressed water at temperatures of 373–463 K and a pressure of 4.0 MPa using a semibatch system—a most effective method because water at high temperature and pressure behaves as a reaction medium with remarkable properties. Under these conditions, thermal softening of G. lucidum occurred, allowing the removal of the polysaccharides protecting other constituents in G. lucidum via hydrolysis. The main massed peaks of water-soluble products were distributed at around 688–2638 m/z with a peak-to-peak mass difference of 162 m/z, consistent with the repeating unit of the glucans. On the basis of these results, this process is proposed as applicable to the isolation of polysaccharides from other types of biomass and may lead to an advanced plant biomass components extraction technology. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.

Decomposition of methyl orange using pulsed discharge plasma at atmospheric pressure: Effect of different electrodes

Abstract: One of the new technologies for water treatment is the pulsed discharge plasma method, which utilizes high voltage pulses with a fast rise time and a very short duration. In this study, under argon atmosphere at 313 K, the decoloration of methyl orange was conducted with copper (Cu) and stainless steel #304 (SUS-304) as electrodes in the batch reactor. The performance of pulse discharge plasma generation was observed using an intensified charge coupled device (ICCD) camera. The results show that the intermediate compounds from the degradation of methyl orange consist primarily of aromatic compounds containing nitrogen functional groups. At the same number of plasma discharge times, the percentage conversion of methyl orange with Cu as the electrode is higher than that with SUS as the electrode. However, the percentage degradation of methyl orange is over 90% in both cases when the number of plasma discharge times was 20000.

Subcritical water extraction and direct formation of microparticulate polysaccharide powders from ganoderma lucidum

Abstract: Ganoderma lucidum (hereafter G. lucidum) has been known as a food and raw material used in the development of medications because of its high content of polysaccharides, or β-glucans, which support the immune function. In this work, subcritical water was applied to utilize G. lucidum for the extraction of polysaccharides at temperatures of 373–463K and a pressure level of 4.0 MPa using a semi-batch system. Furthermore, these extracts were atomized and contacted with hot air to produce microsphere particles. During extraction, thermal softening of G. lucidum occurred, allowing the removal of the polysaccharides and protecting other constituents in G. lucidum via hydrolysis. Scanning electron microscope (SEM) images showed that the microsphere particles formed were spherical and dimpled or shriveled particles with diameters varying from 1 to 6 m. Characteristics of the molecular mass revealed that main massed peaks of water soluble products were distributed at around 688–2636 m/z with a peakto-peak mass difference of 162 m/z, consistent with the repeating unit of the glucans.

Simultaneous Extraction of Water and Essential Oils from Citrus Leavesand Peels Using Liquefied Dimethyl Ether

Abstract: Most of the residues after extracting juice from the citrus fruit are discarded, although they contain valuable substances such as flavonoids and essential oils. While most of the citrus flavonoids are present in the fruit peel, various valuable substances are also contained in the leaves. Moreover, the leaves and peels of citrus plants contain a large amount of moisture; hence, dewatering is essential for extracting valuable substances. Herein, we used liquefied dimethyl ether (DME) as the extractant for dewatering and extraction of valuable substances. With this process, >70% of the water from the wet samples was removed and valuable substances were isolated from the wet samples. The properties of the original and dewatered samples and the extract were evaluated using high-performance liquid chromatography. While the essential oils could be extracted, it was not possible to extract flavonoids by the liquefied DME method.

Synthesis of ZrO2 Nanoparticles by Hydrothermal Treatment

Abstract: Zirconium oxide (zirconia, ZrO2) is the most common material used for electrolyte of solid oxide fuel cells (SOFCs). Zirconia has attracted attention for applications in optical coatings, buffer layers for growing superconductors, thermal-shield, corrosion resistant coatings, ionic conductors, and oxygen sensors, and for potential applications including transparent optical devices and electrochemical capacitor electrodes, fuel cells, catalysts, and advanced ceramics. In this work, zirconia particles were synthesized from ZrCl4 precursor with hydrothermal treatment in a batch reactor. Hydrothermal treatment may allow obtaining nanoparticles and sintered materials with controlled chemical and structural characteristics. Hydrothermal treatment was carried out at temperatures of 150 – 200°C with precursor concentration of 0.1 – 0.5 M. Zirconia particles obtained from this treatment were analyzed by using SEM, PSD and XRD to characterize the morphology, particle size distribution, and crystallinity, respective...

Characteristics of optical emission intensities and bubblelike phenomena induced by laser ablation in supercritical fluids

Abstract: We investigated the characteristics of laser ablation phenomena in supercritical fluids by optical emission and shadowgraph imaging. In comparison with laser ablation in liquid H2O, the optical emission of a laser ablation plasma produced in supercritical H2O had a longer lifetime and a larger transport length. It was found in supercritical CO2 that laser ablation plasmas with bright optical emissions were produced at a mass density of approximately 300 kg/m3. A clear correlation between the optical emission intensity and the density fluctuation was not observed in our experimental results, which were obtained in a regime deviated from the critical point. Bubblelike hollows were observed by shadowgraph imaging in both supercritical H2O and CO2. The dynamics of the bubblelike hollows were different from the dynamics of a cavitation bubble induced by laser ablation in a liquid medium but relatively similar to the dynamics of ambient gas in gas-phase laser ablation.

Subcritical Water Extraction of Resveratrol from Barks of Shorea Roxburghii G. Don.

Abstract: This study investigated subcritical water extraction of trans-resveratrol and its glycosylated form, trans-piceid, from barks of Shorea roxburghii G. Don. The effects of extraction temperature (100-190°C) and water flow rate (2-4 mL/min) at the pressure of 10 MPa were determined on the amounts of compounds extracted. The amount of trans-resveratrol and trans-piceid in the extracts increased with increasing temperature and flow rate, although the increase in flow rate from 3 to 4 mL/min had no significant effect on the extraction yield. Thus the flow rate of 3 mL/min was taken to be the most suitable. At suitable condition (190°C, 3 mL/min), the amount of trans-resveratrol and trans-piceid were 23.18 and 350.28 μg/g dry weight, respectively. With equal extraction duration, the amount of trans-resveratrol and trans-piceid compound obtained from extraction using 190°C subcritical water were higher than those from extractions with ambient water and 80% ethanol.

Comparative Study on Two-Step Fatty Acid Methyl Ester (FAME) Production from High FFA Crude Palm Oil Using Microwave Technique and Conventional Technique

Abstract: The production of biodiesel from crude palm oil (CPO) using microwave technique is investigated and has been compared with conventional heating. Two-step biodiesel production process is applied to maximize the highest biodiesel yield in short reaction time using microwave method. Sulfuric acid (H2SO4) as acid catalysts is used in pre-treatment of feedstock by esterification process followed by potassium hydroxide (KOH) as base catalyst for transesterification process with low methanol to oil ratio. The main purpose of the pre-treatment process is to reduce the free fatty acids (FFA) content of CPO from higher value of FFA content (>6.8%) to a minimum level for biodiesel production (

Fabrication of micro-hollow fiber by electrospinning process in near-critical carbon dioxide

Abstract: Electrospinning is a simple technique that has gained much attention because of its capability and feasibility in the fabrication of large quantities of fibers from polymer with diameters ranging in nano-microscale. These fibers provided high surface area to volume ratios, and it was of considerable interest for many applications, such as nanoparticle carriers in controlled release, scaffolds in tissue engineering, wound dressings, military wear with chemical and biological toxin-resistance, nanofibrous membranes or filters, and electronic sensors. Recently there has been a great deal of progress in the potential applications of hollow fibers in microfluids, photonics, and energy storage. In this work, electrospinning was conducted under high-pressure carbon dioxide (CO{sub 2}) to reduce the viscosity of polymer solution. The experiments were conducted at 313 K and ∼8.0 MPa. Polymer solution containing 5 wt% polymers which prepared in dichloromethane (DCM) with polyvinylpyrrolidone (PVP) to poly-L-lactic acid (PLLA) ratio 80:20 was used as a feed solution. The applied voltage was 15 kV and the distance of nozzle and collector was 8 cm. The morphology and structure of the fibers produced were observed using scanning electron microscopy (SEM). Under pressurized CO{sub 2}, PVP electrospun was produced without bead formation with diameter ranges of 608.50more » - 7943.19 nm. These behaviors hold the potential to considerably improve devolatilization electrospinning processes.« less

Biopolymer Degradation in Sub- and Supercritical Water for Biomass Waste Recycling

Abstract: This chapter discusses the application of sub- and supercritical water for hydrolysis of biopolymer into useful biochemicals, taking cellulose and protein as representative compounds, for biomass waste recycling. It includes the reviews of water properties as a solvent and catalyst for hydrolysis, reactor design and techniques for high-temperature and high-pressure experiments. Several literature focusing on recovery of bioactive compounds from the degradation of the two above-mentioned natural biopolymers from various starting materials are summarized. In addition, carbonic acid enhancement and coupling with microwave, electrolysis and plasma to enhance reaction or extraction rates is also discussed.

Upgrading of Oil Palm Empty Fruit Bunch to Value-Added Products

Abstract: As the second largest producer of palm oil in the world, Malaysia generates a substantial amount of oil palm biomass as agricultural wastes in the forms of empty fruit bunches, shell and fiber, fronds, leaves, and trunks. This biomass feedstock has long been identified as a sustainable source of renewable energy which could reduce the dependency on fossil fuels as the main source of the energy supply and thus lead to reduction of greenhouse gases emission. This chapter highlights the application of oil palm biomass as value-added product and specifically demonstrates the capability of empty fruit bunch as renewable source in generating bio-oil which later could be upgraded as biofuel. Green extraction technique known as supercritical fluid extraction using supercritical CO2 (SC-CO2) was implemented in this study. Effects of two extraction conditions were investigated which includes temperature (60–80 °C) and CO2 flow rate (3–6 mL/min). The extraction was conducted for 2 h using 10 g of OPEFB within particle size 0.15 mm. The crude bio-oil obtained in this study was diluted in 10 mL dichloromethane (DCM) for analysis using gas chromatography-mass spectrometry (GC-MS). Hexadecanoic acid (palmitic acid, C16), dodecanoic acid 1, 2, 3-propanetriyl ester (glycerol trilaurate, C39), and 6 octadecanoic acid (stearic acid, C18:0) were identified as the major compounds.

Effect of Temperature on The Extraction of Bio-oil from Oil Palm Mesocarp Fiber using Supercritical CO2

Abstract: This paper highlights the conversion of oil palm mesocarp fiber into bio-oil via SFE. Effects of extraction temperature which are temperature within 60-90°C are investigated for two hours of extraction time. The yield is diluted in 10ml dichloromethane (DCM) for analysis of gas chromatography-mass spectrometry (GC-MS). The extracted bio-oil is found to contain fatty acid, esters and other long chain hydrocarbon. The concentration of these compounds is determined based on chromatogram peak area. The analysis indicates that fatty acid such as 6-octadecanoic acid (stearic acid), n-hexadecanoic acid (palmitic acid) and dodecanoic acid, 1,2, 3-propanetryl ester (glycerol trilaurate), are the major compounds of the extracted bio-oil. The extraction yield increased from 16.7% to 19.8% once the temperature was increased from 60 to 90°C. Concentration of palmitic acid constantly decreased with temperature. Inversely, myristic acid concentration constantly increased with temperature. However, concentration of glycerol trylaurate, stearic acid and lauric acid was not significantly affected by temperature. Concentration of stearic acid and lauric acid was first reduced once temperature increased from 60 to 70°C yet increased at 90°C and vice versa observation for glycerol trilaurate.

Production method of novel sensation liqueur applying deacidification raw material processing art

Abstract: PROBLEM TO BE SOLVED: To provide a liqueur in which citrus fruit juice including fruit juice (aroma acid citrus fruit juice) of aroma acid citrus and plum fruit juice are included, and drinking feeling is favorable, and aroma is excellent; and a production method of the same that is simple and efficient.SOLUTION: Aroma acid citrus fruit juice, plum fruit juice and the like are treated by a weak basic ion exchange resin to obtain deacidification fruit juice in which an organic acid included in the fruit juice is removed, the same is added to distilled alcoholic liquor and/or brewage, thereby liqueur in which drinking feeling is favorable and aroma is excellent while largely including fruit juice of aroma acid citrus or the like, can be provided by a simple and efficient manner.