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Edible oils with physiological functions, such as fish oil and krill oil, which contain polyunsaturated fatty acids (PUFAs), are highly unstable to heat and oxygen. One of the methods for improving the shelf life of these oils is microencapsulation of the oils through spray drying. This mini-review describes the effects of the surface–oil ratio, oil location within the microcapsules, and oil-droplet diameter on the oxidative stability of functional oils in microcapsules prepared through spray drying. The surface–oil ratio, s, can be expressed through the ratio of the average oil-droplet diameter to the average powder diameter, E, by s = 1 − (1 − 2E)3. Additionally, the effects of oil-droplet size and storage temperature on the stability of the encapsulated oil were examined using squalene as a model functional oil. The activation energy Ea of the squalene degradation rate constant of the Avrami equation can be correlated with the average oil-droplet diameter de. The release behavior of the microencapsulated flavors is also discussed because spray drying is also used for the microencapsulation of flavors. The flavor release rate constant of the Avrami equation is related to the oxygen diffusion coefficient of the wall material. [ABSTRACT FROM AUTHOR]

Anemonefish, including the false clownfish Amphiprion ocellaris, are attractive model organisms because of their unique features, such as sex change and brilliant color patterns in mutants. However, anemonefish are not widely used to study gene function using reverse genetic approaches owing to microinjection difficulties and subsequent rearing and hatching of embryos without parental care. A. ocellaris embryos are spawned on a hard substrate and cared for by their parents until hatching. However, the eggs need to be detached from the substrate and raised without their parents to perform successful microinjection. We established a method to culture and hatch A. ocellaris embryos without spawning substrates or parental care. We found that changing water and generating water flow are critical for culturing the embryos, and that water flow (as physical stimulation) and complete darkness in the dark period are necessary for successful hatching. We further investigated the effectiveness of microinjection into the yolk sac of fertilized eggs rather than into the cytoplasm, which makes microinjection easier. A reporter RNA injected into the yolk sac was transferred to the cytoplasm and translated, indicating that yolk sac microinjection is an efficient alternative as has been used for zebrafish. These findings highlight the potential of A. ocellaris as an experimental model organism for reverse genetics, and our methods could be applied to other anemonefish species. [ABSTRACT FROM AUTHOR]

Spray drying is one of the oldest, most common, and economical techniques typically employed for producing dry powders from flowable feeds which can be a solution, dispersion, or even paste. In the food industry, spray drying technology has also been employed as a means for microencapsulation of food active ingredients such as oils, fragrances, and flavors. Spray drying as a microencapsulation technique provides several beneficial functionalities such as easing handling of liquid labile active compounds, enhancing solubility, improving stability, providing protection against degradation, controlling or delaying release, and masking unpalatable tastes or smells. This article reviews the latest findings and research works on microencapsulation of food core materials by spray drying. It is aimed to give an overview of the vast variety of food active compounds studied in this particular area of interest. This article is organized by the type of food core material, i.e., oil, flavors, antioxidants and polyphenols, nutrients, pigments, vitamins, and enzymes, to facilitate comprehensive discussion on physicochemically similar compounds. [ABSTRACT FROM AUTHOR]

Abstract Chlorination is the most common method to control water qualities, in some case on-site outdoor measurements are required to measure easily-decaying residual chlorine concentration appropriately without delay. In this study sunlight-induced unexpected colour development (UCD) of N , N -diethyl- p -phenylenediamine (DPD) colorimetric measurement was studied under several sun exposure conditions. The colour development level was evaluated with reference to chlorine concentration (mg/L) and relationships between colour development rate (mg/L min) and intensities of solar were investigated. UCD was found to be related to both exposure intensity and time. By means of exposure experiment under specific wavelength of ultraviolet (UV), it was confirmed that both middle and short wavelength of UV radiation being responsible for such an unexpected measurement. Consequently, a simple device was designed using three commercially available anti-UV films, one of which could effectively prevent the UCD from direct sun exposure. Highlights • Unexpected colour development on DPD colorimetric measurement was studied. • Unexpected colour development was related to both sun exposure intensity and time. • Middle and short wavelength of UV radiation were confirmed to be responsible for UCD. • A simple device was designed to effectively shield UCD from direct sun exposure. [ABSTRACT FROM AUTHOR]

In recent years, various catastrophic disasters have increased in Japan. In coastal areas, heavy rains and tsunamis tend to cause enormous damage. Because large vessels cannot enter the port, rescue operations are delayed more than expected. Therefore, it is important to develop a reliable device for discovering shipping lanes and ensuring a safe route for prompt rescue activities. In this research, we have created an underwater robot that can be applied for this purpose at the early stage right after disasters. Disaster-relief drills were conducted in Kagoshima Bay to examine its effectiveness. Fishery high school students manufactured, operated, and repaired the robot using the knowledge they had learned in classes. [ABSTRACT FROM AUTHOR]

Natural antifouling products have been the subject of considerable attention. We screened marine algae for antifouling activity and discovered omaezallenes, the new bromoallene-containing natural products isolated from the red alga Laurencia sp. Described is the isolation, structure elucidation, and total syntheses of omaezallenes. The relative and absolute configurations of natural omaezallenes were unambiguously established through total synthesis. The antifouling activities and ecotoxicity of omaezallenes were also evaluated. [ABSTRACT FROM AUTHOR]

The polymer-coated inclusion complex powder formation of D-limonene and β-cyclodextrin obtained by spray drying was investigated with respect to the effects of various types of polymer coating agents on the powder particle size and morphology. The addition of the polymer coating agent affected the average particle size, morphology, and internal structures of the spray-dried powders. The average particle diameter of the uncoated spray-dried powders was approximately 5 µm. The powder particle size increased upon the addition of a polymer coating reagent. With the addition of 9 wt% of the polymer coating agent, an average diameter of approximately 80 µm was obtained for the spray-dried powder particles. However, further addition showed a negligible effect on the particle size. Inclusion complex crystals were observed on the surface and inside of the powder particles. [ABSTRACT FROM PUBLISHER]

A linearly ramped humidity system coupled with automatic sampling gas chromatography has been developed. The apparatus was adopted to measure the dynamic release flux of D-limonene included in spray-dried β-cyclodextrin (β-CD) and the polymer-coated counterparts under linearly ramped humidity (0.375%/min) at constant temperature (50°C). The release flux profiles of D-limonene were analyzed using a mathematical model based on an extended Arrhenius equation. The activation energy of D-limonene release flux from β-CD was 278 (kJ/mol), which was the highest among the powders and around twice as high as our previous results obtained by the conventional static method. [ABSTRACT FROM AUTHOR]

The ramping method for humidity at constant temperature was used to evaluate the release of D-limonene from spray-dried powder using a handmade dynamic vapor sorption (DVS) instrument. The release fluxes of D-limonene from spray-dried powder at two different liquid feed temperatures, 40 and 80°C, were used to evaluate the flavor release properties of spray-dried powder. The flavor fluxes for 40°C of liquid feed temperature were faster than those for 80°C over the whole humidity range. [ABSTRACT FROM AUTHOR]

Oil mixtures of medium-chain triglycerides (MCT) and d-limonene in mixing ratios from 10 to 100 wt% were encapsulated in modified starch (wall material) by spray drying to produce oil-rich powders. The oil load (mass ratio of oil mixture to wall material) of the infeed emulsion markedly influenced the properties of the infeed liquid and the characteristics of the resulting powder. The viscosity of the infeed liquid and the particle size of the powder exponentially decreased with increasing oil load, while the emulsion droplet size in the infeed liquid increased. In addition, retention of d-limonene during spray drying also decreased markedly with increasing oil load. Irrespective of the different oil loads and concentrations of the wall material, d-limonene retention was well correlated with the emulsion droplet diameter of the infeed liquid. The encapsulation efficiency of the oil mixture exhibited a maximum value (almost 100%) at an oil load between 0.5 and 1.0, before decreasing at higher oil loads. At an oil load of 2.0, the encapsulation efficiency of d-limonene was reduced to almost zero, while around 40% of the initial MCT was encapsulated in the powder. The increase in oil load also led to increased amounts of surface oil of MCT and d-limonene in the resulting powder due to the increasing emulsion droplet diameter of the infeed liquids. Practical Application: This study proposes the microencapsulation of medium-chain triglycerides under high-oil-load conditions by spray drying. The powders prepared by this process provide significant benefits in terms of rapid energy conversion after consumption without accumulation in the body. Important quality factors of the powder products such as the encapsulation efficiency and the amount of surface oil were examined to understand the optimum process conditions for spray drying. [ABSTRACT FROM AUTHOR]

S-Adenosyl-L-methionine (SAM) production from Saccharomyces cerevisiae K-9 was comparatively stable under slightly acidic conditions (pH 3.0-5.0) and at low temperature (20-25°C). The kinetics of SAM degradation and 5'-methylthioadenosine (MTA) formation in yeast solution at high temperature (40-60°C) were described by zero-order reactions and the activation energy levels were 104 and 102 kJ/mol, respectively. The optimum retention of SAM after spray drying was obtained at 120°C inlet air temperature. The water content of the powder has a significant effect on the stability of SAM. The SAM yeast powder with trehalose and maltodextrin (dextrose equivalent, DE = 25), used as carrier solids, exhibited higher stability. [ABSTRACT FROM AUTHOR]

A feeding experiment was conducted to examine the potential use of defatted soybean meal (SBM) and freeze-dried meat of blue mussel (BM) as partial replacement of fish meal in the diet of tiger puffer. Eight experimental diets were formulated, in which 0, 20, 40 and 60% fish meal protein were replaced with SBM (S0B0, S20B0, S40B0, and S60B0), and 40 and 60% with a combination of SBM and BM (S30B10, S20B20, and S45B15, S30B30). Fish of 11 g initial body weight were fed the diets to satiation twice daily, 6 d/wk for 8 wk at 20 C. Specific growth rate, feed efficiency, and protein efficiency ratio (PER) of fish fed diets containing SBM as an alternative protein source for fish meal decreased with increasing level of SBM, and these parameters of fish fed S40B0 and S60B0 diets were significantly lower than those of the control. Growth of fish in dietary groups containing BM were statistically identical to those in the control, and tended to increase with increasing level of dietary BM both at 40 and 60% substitution levels. Growth and feed utilization of fish fed S20B20 were almost the same to those in the control. [ABSTRACT FROM AUTHOR]

The acute toxicities of copper were examined for Japanese flounder, Paralichthys olivaceus, and red sea bream, Pagrus major, in terms of fish size and water temperature. Artificial seawater of low pH of 5.4–6.7 was used as testing water to keep dissolved copper concentration at 0.04–41 mg Cu/L. Japanese flounder of 0.3–17 g and red sea bream of 0.5–13 g were exposed to different concentrations of copper for 96 h at 20 C under semistatic condition. Median-lethal concentration for 96 h of Japanese flounder and red sea bream were 8.7–12.2 and 2.0–5.2 mg Cu/L, respectively. No significant relationships were observed between median-lethal concentrations for 96 h and fish size for Japanese flounder, while the value decreased significantly with increasing fish size for red sea bream. Effect of water temperature on the acute toxicity was examined for Japanese flounder of 0.3 and 0.4 g at 10, 15, 20, and 25 C and red sea bream of 0.5 and 1.0 g at 12, 15, 20, and 25 C. Ninety-six-hour median-lethal concentrations for Japanese flounder and red sea bream were 5.1–11.2 and 1.0–5.3 mg Cu/L, respectively. No significant relationships were observed between median-lethal concentrations for 96 h and water temperature for both fish species. [ABSTRACT FROM AUTHOR]

Spray drying is commonly used as a dehydration technique in the pharmaceutical industry for making powdery products directly from liquid. It is also an attractive alternative for obtaining solid pharmaceutical molecules that are traditionally produced by freeze drying. Spray drying is often regarded as a harsh drying method, due to the high temperature of the drying gas. Therefore, some excipients were added to improve the stability in manufacturing process and storage. Emphasis was placed on the encapsulation of proteins by spray drying and crystal transformation method. [ABSTRACT FROM AUTHOR]

Two 12-wk rearing experiments were conducted to examine the effect of rearing salinities of 10–35 ppt on the growth of 3- and 170-g-size tiger puffer, Takifugu rubripes. Fish were reared in a closed recirculation system without introducing fresh culture water at 23 C and were fed commercial pellet diet for tiger puffer twice or three times daily to apparent satiation each, almost everyday. Growth of 3-g-size fish seemed to increase with decreasing salinity; however, there were no significant differences in the specific growth rate and weight gain among treatments because of differences in initial body weight. Final body weight and length of fish reared at 10 ppt were significantly higher than those for fish reared at 30 ppt although initial sizes were similar. Differences were not found for the feed efficiency (FE) and daily feed consumption. Apparent relationships were not observed between salinity and blood characteristics or proximate compositions of muscle of the cultured fish. Differing from smaller fish, growth of 170-g-size fish tended to decrease with decreasing salinity from 30 to 10 ppt and with increasing salinity from 30 to 35 ppt. Similar trends for FE were observed. [ABSTRACT FROM AUTHOR]

The retentions of alcohol dehydrogenase (ADH) activity during drying and storage were investigated at various temperatures and relative humidities for various carbohydrate solutions. The highest retention of ADH activity after drying was obtained for the mixture of trehalose and methyl-ß-cyclodextrin. For a single dried droplet, the effects of humidity on the storage stability of ADH were reversed between the trehalose solution and the blend of trehalose and methyl-ß-cyclodextrin. However, the addition of methyl-ß-cyclodextrin decreased the residual activity of ADH during storage. The carbohydrate matrix structure after drying might influence mainly the storage stability of ADH encapsulated in the mixed carbohydrate of trehalose and methyl-ß-cyclodextrin. [ABSTRACT FROM AUTHOR]

Powdery encapsulation of shiitake flavor was investigated by spray drying with the mixture of cyclodextrin (CD) and maltodextrin (MD). Solubilities of cyclic sulfur compounds except hexathiepane increased with a-CD concentration. Stability constant of lenthionine to a-CD was 5.30 mmol -1 L. The retentions of lenthionine and hexathiepane depended on a type of cyclodextrin. When the encapsulant was a-CD, the addition of MD had a remarkable effect on increasing the flavor retention. This might be due to the high stability constants of shiitake flavors in a-CD. The encapsulant in 3 wt% of a-CD and 27 wt% of MD resulted in the highest retention for lenthionine and other shiitake flavors except hexathiepane. This result suggests that shiitake flavors except hexathiepane have almost same stability constants to a-CD. [ABSTRACT FROM AUTHOR]

Investigates powdery encapsulation of shiitake flavors, extracted from dried shiitake, by spray drying. Increase in flavor retention with an increase in drying air temperature and solid content; Decrease in flavor retention with an increase in dextrose equivalents of maltodextrin; Markedly increased flavor retention due to the use of α-cyclodextrin and maltodextrin in combination as an encapsulant.

Although the π/4 phase shift modulation schemes used in quadrature phase shift keying (QPSK) are important approaches to ensuring efficient frequency usage in digital portable telephone systems, they also require linearity of the power amplifiers, they also require linearity of the power amplifiers, which is an undesirable constraint from the standpoint of efficiency. In this work, we describe a unified approach to this problem based on the idea that distortion can be effectively decreased by creating dips or “bumps” in the intermod characteristics, due to the dependence of the adjacent channel power (ACP) leakage on input power. For the special case of an impedance Zes connected to the gate of a FET, we use Volterra series to quantitatively demonstrate how the appearance of such dips or bumps is related both to Zes and to the fifth intermod (IM5). We then show analytically that when these dips or bumps are generated effectively, they can suppress IM5. Finally, we show that the resulting decrease in intermodulation distortion and improved efficiency make this method useful in the design of MMIC power amplifiers used in Personal Handy Phone (PHS) service. © 2002 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 85(4): 10–21, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.1100 [ABSTRACT FROM AUTHOR]

The flavor inclusion powder was prepared by spray drying, using the combined encapsulation method of inclusion by β-cyclodextrin (β-CD) and emulsified by gum arabic (GA). d-Limonene and ethyl n-hexanoate were used as model flavors. The application of high pressure by Microfluidizer to the mixture of flavors and β-CD slurry was an effective means of forming inclusion complex. Flavor retention during spray drying under various compositions of the encapsulants was investigated. The flavor retention using the blended encapsulant was increased by adding GA in the encapsulant. The characteristics of release of encapsulated flavor during storage were evaluated at 50°C and 75% of relative humidity. The release rate of flavor in spray-dried powder depended on kinds of the flavors and composition of the encapsulant. The blending MD and β-CD in the feed liquid decreased the release rate of flavors. The rate of release of flavor was analyzed by Avrami's Equation. [ABSTRACT FROM AUTHOR]

The retention of emulsified flavor during spray drying was investigated under various compositions of feed liquid. Drying of the emulsion solution was carried out in a spray dryer, equipped with a centrifugal atomizer. The retention of d-limonene during spray dying was nearly hundred percent independent of the composition of the feed liquid, whereas the retention of ethyl butyrate emulsified by gum arabic (GA) was much lower (0–20%). The retention of ethyl butyrate was markedly dependent on the concentration of maltodextrin and the type of emulsifier, indicating that the stability of emulsion is a controlling factor for flavor retention. The use of mixing emulsifiers, adjusting of density of ethyl butyrate, and the addition of 1% gelatin were quite effective procedures to improve the retention of ethyl butyrate, particularly when emulsified by GA. [ABSTRACT FROM AUTHOR]

Desorption isotherms of Japanese noodle (udon) were obtained at 20, 30 and 40°C, and analyzed by several isotherm models. The desorption isotherm data satisfactorily correlated with the GAB equation and the Oswin and Smith equations. The binding energy of moisture was calculated by Clausius–Clapeyron equation and found to be negligibly small above the moisture content of 0.163 kg water/kg solid. The sorption enthalpy calculated from the Arrhenius plot of GAB parameter was similar to the binding energy from Clausius–Clapeyron equation at GAB monolayer moisture content. [ABSTRACT FROM AUTHOR]