• Applied Biological Chemistry
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• v.50 no.2
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• pp.87-94
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• 2007

A bacterium which has high enzymatic activities such as amylase, cellulase and protease was isolated from Korean traditional soybean food, doenjang. The isolated bacterium was identified to Bacillus subtilis HS25 by the test of morphological and biochemical properties according to Bergey's Manual of Systematic Bacteriology and API 50 CHL kit, and by the 16S rDNA sequence. The isolated B. subtilis HS25 had a potent antibacterial activity against food born causative or pathogenic bacteria. B. subtilis HS25 is endospore forming cell and contained flagella and abundant viscous material at the out layer of cell wall. It was rod type bacterium $(0.5{\sim}0.8{\times}3{\sim}5{\mu}m)$ having biochemical characteristics such as gram staining(+), catalase(+), oxidase(-) and hydrolysis of esculin(+). The optimal medium compositions for production of antibacterial substance in the B. subtilis HS25 were 1% of soluble starch, 0.5% of yeast extract, 0.5% of peptone and 0.05% of MgCl$_2{\cdot}6H_{2}O$. The optimum temperature and pH of the growth of the B. subtilis HS25 was 35$^{\circ}C$ and pH 7.5, respectively. The antibacterial activity was more high in neutral to a little alkaline pH (6.5-10.5) than in acidic pH. The optimal shaking speed to grow and to produce antibacterial substance of the B. subtilis HS25 was 160${\sim}$200 rpm. The optimal culture time for antibacterial activities of the bacterium were shown to be in the range of 12-36 hr.

• Journal of the Korean Applied Science and Technology
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• v.20 no.2
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• pp.101-109
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• 2003

Provitamin $B_5$ liquid crystal ($PVB_5$-LC) was the new emulsion system to enhance moisturizing activity on the skin. In this study, it should be mentioned that PVB5-LC could be prepared with the main compound of hydrogenated lecithin (HL) in oil-in water (O/W) emulsion. The key ingredient of humectants was contained 2% of provitamin $B_5$ ($PVB_5$) into the $PVB_5$-LC. The best suitable compositions of $PVB_5$-LC were made from 4.0 wt% of HL, 4.0 wt% of cetostearyl alcohol (CSA) as emulsifier and gelling agent, 3.0 wt% of 1,3-butylene glycol (1,3-BG) and 2.0 wt% of glycerin as moisturizers, 3.0 wt% of cyclomethicone (CMC), 3.0 wt% of isononanoate (ININ), 3.0 wt% of capric/caprylic triglyceride (CCTG), 3.0 wt% of macadamia nut oil (MNO) as emollients. As the analytical result of $PVB_5$-LC, it could know that the distribution range of particle size was 0.14 to 12.37 m level (mean size 3.24 m). It was certified the multi lamellar phase around the droplet of liquid crystal when observed the droplet particles through a polarization microscope. And it clinically was tested the effectiveness of moisturizing activity (in-vivo) compared with control sample (O/W emulsion). The effectiveness of moisturizing activity of $PVB_5$-LC with Skincon-200EX after 6 hours went up 49.0% (p<0.05, n=20) whereas the effectiveness of moisturizing activity of generally O/W emulsion cream was 25.7% (p<005, n=20). Also, in case of Comeometer CM-825, the moisturizing activity of $PVB_5$-LC after 6 hours rose 36.6% (p<0.05, n=20) whereas the effectiveness of moisturizing activity of generally O/W emulsion cream was 10.8%. Therefore, it was known that the effectiveness moisturizing activity of $PVB_5$-LC with HL was remarkably superior compared with O/W emulsion cream.

• Journal of the Korean Applied Science and Technology
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• v.31 no.1
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• pp.113-119
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• 2014

The compositions of saturated and unsaturated fatty acids in biodiesel feedstocks are important factors for biodiesel properties including low-temperature fluidity and oxidative stability. This study was conducted to improve low-temperature fluidity of biodiesel by reducing total saturated FAME (fatty acid methyl ester) in animal fat biodiesel fuels via urea-based fractionation and by mixing plant biodiesel fuels (rapeseed-FAME, waste cooking oil-FAME, soybean-FAME, and camellia-FAME) with enriched-polyunsaturated FAME derived from animal fat biodiesel. Our results showed that the reduction of total saturated FAME in animal fat biodiesel lowered CFPP (Cold Filter Plugging Point) to $-15^{\circ}C$. Mixing plant biodiesel fuels with the enriched-polyunsaturated FAME derived from animal fat biodiesel lowered CFPP of blended biodiesel fuels to $-10{\sim}-18^{\circ}C$.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.802-812
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• 2016

Silicone foam is very useful as flame resistant material for many industrial areas such as high performance gasketing, thermal shielding, vibration mounts, and press pads. A silicone foam was prepared through simultaneous crosslinking and foaming by hydrogen condensation reaction of a vinyl-containing polysiloxane (V-silicone) and a hydroxyl-containing polysiloxane (OH-silicone) with hydride containing polysiloxane (H-silicone) in the presence of platinum catalyst and imorganic filler at room temperature. This is more convenient process for silicone foam manufacturing than the conventional separated crosslinking and foaming systems. Funtionalized silicones we used in this experiment were consisted with a V-silicone containing 1,0 meq/g of vinyl groups and a viscosity of 20 Pa-s, an OH-silicone with 0.4 meq/g of hydroxyl groups and a viscosity from 50 Pa-s, and an H-silicone containing 7.5 meq/g of hydride groups and a viscosity of 0.06 Pa.s. The effects of compositions of functionalized silicones and additives, such as catalyst and filler on the structure and mechanical properties of silicone foam were studied. 0.5 wt% of Pt catalyst was enough to accelerate the foaming rate of silicone resins. The addition of OH-silicone with lower viscosity accelerates the initial foaming rate and decreases the foam density, but the addition of V-silicone with lower viscosity reduces the tensile strength as well as the elongation. The final foam density, tensile strength, and elogation of silicone foam prepared under the SF-3 condition increase maximum to $0.58g/cm^3$, $3,51kg_f/cm^2$, and 176 %, repectively. We found out the filler alumina also played an important role to improve the mechanical properties of silicone foams in our foaming system.

• Journal of the Korean Applied Science and Technology
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• v.37 no.3
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• pp.516-525
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• 2020

The densities of aqueous solutions of the amphiphile 2-(2-hexyloxyethoxy)ethanol (C₆E₂) were measured at 279.15 K and 282.15 K by vibrating-tube densitometry. Then using the density data of the binary C₆E₂ (1)/water(2) system, the excess volumes and partial molar volumes were determined at various compositions. Excess volume V^E exhibits negative deviation for the whole region of composition, which implies relatively stronger attraction between molecules. At the C₆E₂ mole fraction of around 0.45, V^E was at its minimum. Partial molar volume ${\bar{V}}_1$ increases monotonously with the mole fraction x₁(=x) and ${\bar{V}}_2$ decreases with x. Any particular point in ${\bar{V}}_1$ and ${\bar{V}}_2$, which may point to molecular association, was unobserved.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.69-82
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• 1994

In order to find out physiological effects of diets supplemented with seamustard (Undaria pinnatifida) on the growth, survival rate, body compositions and blood properties of young rockfishes (Sebastes schlegeli) in range of average total length from $2.99{\pm}0.23\;cm\;to\;18.52{\pm}1.07\;cm$ and average body weight from $1.03{\pm}0.18\;g\;to\;120.64{\pm}19.32\;g$, experiments were performed for 140 days by feeding four experimental diets supplemented with $0\%,\;3\%,\;5\%\;and\;7\%$ of seamustard powder. In addition, the tests on tolerance of the fishes against low $O_2$ saturation and starvation were carried out after the feeding experiments. The fishes fed diet supplemented with $5\%$ of seamustard powder revealed the best results in growth of total length and body weight. Crude lipid content in the whole viscera of fishes fed diets supplemented with seamustard powder was higher than that of fishes fed diet without seamustard powder, while the moisture, crude protein, crude lipid and crude ash composition in the dorsal muscle did not show any remarkable differences among diet groups with or without seamustard powder. Hematocrit and mean number of red blood cell in fishes fed diets supplemented with seamustard powder was elevated, despite of no notable changes in mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration. The resistance of the fish to low $O_2$ saturation was elevated by feeding seamustard powder. Upon the starvation of fish for 31 days after the feeding experiments, body weight loss of three groups fed diets with seamustard was smaller compared with the group fed diet without seamustard.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.393-408
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• 1996

The effect of various levels of ascidian tunic extracts and carophyll pink on the growth rate, pigmentation, lipid and total cholesterol accumulation, and fatty acid compositions were studied in kuruma prawn, Penaeus japonicus. The kuruma prawn was fed the purified diets with or without ascidian tunic extract and carophyll pink at the levels of 100, 200, and 400 ppm for 8 weeks. In the experiment diet with ascidian tunic extracts or carophyll pink, the values of daily growth rate were ranged between $1.065\;to\;1.292%$, compared with control group. The content of astaxanthin in kuruma prawn was not significantly affected by the feeding levels of tunic extracts. Feeding of the tunic extracts, on the other hand, increased the kuruma prawn lipid and total cholesterol content, and pigment deposition in concentration-dependent manners without influencing the free astaxanthin concentration of prawn flesh and heads between two feeding groups(200 and 400 ppm). And it was also demonstrated that the dietary astaxanthin was deposited in kuruma prawn body tissue mainly as astaxanthin esters. The results suggest that the best feeding strategy for pigmentation in kuruma prawns is the diets with ascidian tunic extracts at the level of 4g/kg feed (200 ppm) for 8 weeks.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.466-472
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• 1997

Peptides separated from fish paste washing liquid of an Alaska pollak (Theragria chalcogramma) were purified and characterized. The fish paste washing liquid (supernatant) was separated by centrifugation of fish paste homogenate. The fish paste washing liquid of $0.5\%$ concentration was hydrolyzed for 24 hour at $50^{\circ}C$ by immobilized protease in bioreactor and decomposing liquid of protein having $50\%$ decomposing rate (OPA method) was obtained. The crude peptide fractions were obtained from this liquid by Dowex 50w $(H^+)$ column chromatograpy. Purified peptides (SP-fraction peptides) were fractionated by using SP-Sepadex C-25 $(H^+)$ column chromatography. Molecular weights and amino acid compositions of these peptides were estimated by Sephadex G-50 column chromatography and HPLC, respectively. when the washed peptides was eluated with $0.6\~0.9\%\;and\;1.2\~2.0\%$ of NaCl, peptides composed of weakly basic amino acids and strongly basic amino acid were respectively eluted. Molecular weights of each peptide fractions showed the broad distribution from 1,000 Da to 3,000 Da in the order of SP-4>SP-3>SP-2>SP-1. Peptides contained a large quantity of glycine, arginine, glutamic acid, and alanine in the washed peptide and its SP-tractions, respectively.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.1
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• pp.1-8
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• 2006

For the effective utilization of tuna processing byproducts such as roes of skipjack tuna (Katsuwonus pelamis) and yellowfin tuna (Thunnus albacores) as a food resource, the roes of skipjack and yellowfin tuna were examined on food component characteristics and also compared to those of Alaska pollack (Theragra chalcogramma). The concentrations of heavy metal in both roe of the skipjack and yellowfin tuna were below the reported safety limits, therefore, these roes appeared to be safe as a raw material for food resource. The contents of crude protein were 21.4% in the skipjack tuna roe and 21.5% in the yellow fin tuna roe, which showed to be the major component in tuna roes. The prominent amino acids of total amino acids were aspartic acid, glutamic acid, leucine and lysine, and these amino acids were comprise to be 38.4-41.2% of total amino acid in both tuna roes. The total lipid content were 2.1 % in the skipjack tuna roe and 2.0% in the yellofin tuna roe. The major component of total lipid was found to be triglyceride in both tuna roes (skipjack tuna roe, 93.3%; yellow fin tuna roe, 92.0%), which was high in the compositions of 16:0, l8:1n-9, and 22:6n-3. The content of DHA in total lipid of the tuna roes (skipjack tuna roe, 29.9%; yellowfin tuna roe, 36.3%) were higher than that of Alaska pollack roe (18.1%). Based on the results of the proximate composition, mineral, amino acid and lipid characteristic, roes of skipjack tuna and yellowfin tuna showed potential as a raw material for food.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.3
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• pp.185-193
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• 1976

The sterol compositions of the Pelecypoda, M. sultataria, S. sachalinensis, and the Gastropoda, H. discus hannai Inc, T. cornutus were investigated. The results areas follows: 1. The contents of the unsaponifiables and sterols of the Pelecypoda, M. sulcataria, S. sathalinensis, and the Gastropoda, H. discus hannai Ino, T. cornutus, are $12.0\%,\;11.8\%,\;and\;16.2\%,\;15.3\%$, respectively. 2. The complex sterols from the Pelecypoda and Gastropoda are well separated on Silica Gel HF 254 TLC impregnated with $15\%$ silver nitrate. 3. The prominent sterols of the Pelecypoda, M. sulcateria and S. sachalinensis, are 22-trans-24-norcholesta-5, $22-dien-3\beta-ol$ $3.0\%\;3.9\%$ 22-dehydrocholesterol $6.7\%,\;10.2\%$, cholesterol $39.0\%,\;48.6\%$ brassicasterol $14.1\%,\;13.8\%$ 24-methylenecholesterol $19.4\%,\;11.5\%$, stigmasterol $2.4\%,\;0\%$ $\beta-sitosterol\;10.5\%,\;11.9\%$, and fucosterol $4.3\%,\;0\%$. 4. Abalone, H. discus hannai Ino, and T. cornutus contain cholesterol $98.0\%,=97.5\% as main component with small amounts of 22-dehydrocholesterol, brassicasterol and desmosterol. In H. discus hannai rno, 24-methylenecholesterot and fucosterol are also found.