• KSBB Journal
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• v.6 no.3
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• pp.271-279
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• 1991

Phosphatidylglycerol(PG) and two unnatural phospholipids, phosphatidylethyleneglycol (PEG) and phosphatidylpropyleneglycol(PPG), were synthesized from ovolecithin using cabbage phospholipase D(PLD) in a emulsion system. Optimum pH and temperature for the enzymatic synthesis of PG, PEG and PPG in the emulsion system was 5.0-5.6 and 37$^{\circ}C$, respectively. The maximum activity for transphosphatidylation was obtained with 30-80 mM Ca++. Addition of 25% glycerol was required to convert completely ovolecithin to PG, whereas 16% glycerol was sufficient to attain the highest rate of conversion for both PEG and PPG syntheses, the highest conversion rate was obtained with addition of either 10% ethyleneglycol or propyleneglycol. However, the concentration of alcoholic acceptor should be increased up to 20% to improve selectivity up to 100% for PEG or PPG synthesis. Identification of PEG and PPG was made by analyzing the polyvalent alcohols released after their hydrolysis by HCl or PLD.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.258-261
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• 1997

For the efficient production of lysophospholipid the hydrolysis of phospholipid using phospholipase $A_1$ from Serratia sp. MK1 was studied in an aqueous-solvent, a two-phase and an emulsion system. Judged on the basis of productivity and the degree of hydrolysis, the yield of lysophospholipid in a two-phase system was found to be better than that obtained in an emulsion system. Among the 13 organic solvents tested phospholipase $A_1$ showed the most efficient catalytic activity and stability in butyl acetate. When 20% phospholipid was used it was completely hydrolyzed in this two-phase system.

• Food Science of Animal Resources
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• v.37 no.2
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• pp.274-287
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• 2017

This study was performed to investigate the effect of Gleditsia sinensis Lam. extract on the physicochemical properties of emulsion-type pork sausages during storage at $10^{\circ}C$ for 4 wk. Treatments were as follows: (C, control; T1, sodium ascorbate 0.05%; T2, Gleditsia sinensis Lam. 0.05%; T3, Gleditsia sinensis Lam. 0.1%; T4, Gleditsia sinensis Lam. 0.2%; T5, Gleditsia sinensis Lam. 0.1% + sodium ascorbate 0.05%). The values of pH, moisture content, lightness, redness, and sensory attributes were all significantly decreased, while the yellowness, chroma, hue angle, and texture properties were increased during storage with increase of the Gleditsia sinensis Lam. extract added. In addition, the antioxidant activity and antimicrobial activity in the sausages displayed significant increases (p<0.05). Therefore, although it was concluded that the addition of Gleditsia sinensis Lam. extract is not effective for improvement of the physical properties compared to chemical additives in sausages, it could be applied to meat products as a natural preservatives.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.566-569
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• 2005

The extracellular polysaccharide...(EPS) has been used in a wide variety of industrial applications because of gel formation, emulsion stability, control of the surface tension, water absorption and film formation etc. In this study, inhibitory activity on tyrosinase and inhibitory activity on angiotensin converting enzyme...(ACE) are determined. UV adsorption wavelength, beads formation of EPS were investigated. In the result, in 1%(w/v) EPS concentration, EPS had inhibitory activity of 71.8% on tyrosinase and inhibitory activity of 61.5% on angiotensin converting enzyme in 1.5% EPS concentration. Adsorption wavelength of EPS was UV-B,C . Beads based on EPS were prepared by w/o emulsion method and the shape of EPS beads observed by SEM was spherical and uniform.

• Journal of the Korean Ceramic Society
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• v.55 no.5
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• pp.446-451
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• 2018

In this study, different formulations of magnesium oxide and various modifiers (phosphoric acid, ferrous sulfate, pure acrylic emulsion, silicone acrylic emulsion, glass fiber, and polypropylene fiber) were used to prepare magnesium oxychloride cement composites. The compressive strength of the magnesium oxychloride cement was tested, and the softening coefficients of the composites after soaking in water were also calculated. The results showed that a magnesium oxychloride cement sample could not be coagulated when the MgO activity was 24.3%, but the coagulation effect of the magnesium oxide cement sample was excellent when the MgO activity was 69.5%. While pure acrylic emulsion, silicon-acrylic emulsion, and glass fiber showed insignificant modification effects on the magnesium oxychloride cement, ferrous sulfate heptahydrate, phosphoric acid, and polypropylene fiber could effectively improve its water resistance and compressive strength. When the phosphoric acid, ferrous sulfate heptahydrate, and polypropylene fiber contents were 0.47%, 0.73%, and 0.25%, respectively, the softening coefficient of a composite soaked in water reached 0.93 after 7 days, and the compressive strength reached 64.3 MPa.

• Food Science and Preservation
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• v.17 no.4
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• pp.435-443
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• 2010

Physicochemical and functional properties of collage from skate skin (Raja Kenojei) are examined depending on pH and NaCl concentration in the medium. The solubility decreased as NaCl concentration increased but, turbidity increased as concentration of collagen increased. Oil-holding capacity and water-holding capacity were similar to other fish skin collagens. Emulsion activity, creaming stability, and viscosity were lowest at where pH levels were isoelectric point regions of collagens. However, the higher pH values at 7.0-9.0 caused increasing foam expansion, foam viscosity, and gel strength. These results indicated that collagen from skate skin could be used as a functional ingredient for food and industrial applications.

• Proceedings of the Membrane Society of Korea Conference
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• 2003.07a
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• pp.65-68
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• 2003

The paper discusses the use of stable emulsion, prepared by membrane emulsification technology, to improve the enantiocatalytic performance of immobilised lipase in multiphasic membrane reactors. The production of optical pure (S)-naproxen from racemic naproxen methyl ester has been used as model reaction system. The enzyme was immobilised in the sponge layer (shell side) of capillary polyamide membrane with 50 kDa cut-off, The O/W emulsion, containing the substrate in the organic dispersed phase, was fed to the enzyme membrane reactor from shell-to-lumen. The results evidenced that lipase maintained stable activity during all the operation time (more than 250 hours), showing an enantiomeric excess (96 $\pm$2%) comparable to the free enzyme (98 $\pm$ 1%) and much higher compared to similar lipase-loaded membrane reactors used in two-separate phase systems (90%). The study showed that immobilised enzymes can achieve high stability as well as high catalytic activity and enantioselectivity.

• Food Science of Animal Resources
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• v.41 no.6
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• pp.1060-1077
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• 2021

Food additives are required to maintain the freshness and quality of foods, particularly meats. However, chemical additives may not be preferred by consumers, and natural materials with antimicrobial and antioxidant effects may be used as replacements for common chemical additives. Accordingly, in this study, we compared the antimicrobial and antioxidant activities of natural compounds extracted with ethanol and hot water, and emulsion sausage prepared with natural ethanol extracts was analyzed for pH, color, thiobarbituric acid reactive substances (TBARS), and Clostridium perfringens growth during storage. The antimicrobial activities of 49 natural extract candidates against Listeria monocytogenes, C. perfringens, Salmonella spp., and Escherichia coli were analyzed, and six natural materials with excellent antibacterial activities, i.e., Elaeagnus umbellata Thunb. f. nakaiana (Araki) H. Ohba, Punica granatum L., Ecklonia cava, Nelumbo nucifera Gaertner, and Schisandra chinensis (Turcz.) Baill., and Rubus coreanus Miq. were evaluated to determine their total polyphenol contents and DPPH radical scavenging activities. The total polyphenol contents of ethanol extracts were higher than those of hot water extracts, whereas DPPH radical scavenging activity was found to be higher in hot water extracts. The TBARS values of emulsion sausages were significantly increased as storage time increased, and the TBARS values of emulsion sausages prepared with natural extracts were lower than those of control sausages. Natural extract-treated emulsion sausages showed a 99% reduction in bacterial contents compared with untreated sausages on day 2, with greater than 99.9% reduction after day 3. Thus, these results demonstrated that natural extracts could have applications as natural preservatives in meat products.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.361-367
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• 1996

As a part of investigation for quality improvement of surimi gel from fish with a red muscle by addition of emulsion curd, we investigated the processing conditions of emulsion curd contained succinylated gelatin from conger eel skin as an emulsifier and emulsion curd-added surimi gel. Activity and stability of emulsion curd on standing at room temperature, chilled temperature and vibration were remarkably improved by the addition of 15 tunes of soybean oil and 5 times of water to succinylated gelatin from conger eel skin. The proximate composition of the emulsion curd was moisture 18%, protein 5%, lipid 76% and ash 0.5% and its appearance was white. Peroxide value and fatty acid composition of emulsion curd contained succinylated gelatin as an emulsifier were similar to these of soybean oil. By the addition of 6% of emulsion curd to mackerel surimi, gel strength, appearance and texture of the resulting surimi gel were improved, while its peroxide value and brown pigment revealed minor change. From the results of volatile basic nitrogen, viable cell counts and histamine content, the emulsion curd-added mackerel surimi gel can be safe In the sense of food sanitation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.696-700
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• 2008

The objective of this study was to investigate the genotoxicological safety and biological functions of octadeca-9,12-dienyl-3,4,5-trihydroxybenzoate (GA-LA) in cream-based emulsion for future application as a functional cosmetic material as well as food. GA-LA was synthesized chemically from gallic acid and linoleic acid. The Ames test showed that GA-LA did not have mutagenical toxicity. The control cream-based emulsion containing GA-LA was prepared by commercial method and tested for 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Ferric reducing antioxidant power (FRAP) and inhibition effect against tyrosinase of the emulsions were tested for the evaluation of antioxidative and skin-whitening activities. The results showed that DPPH radical scavenging activity in the cream-based emulsion containing GA-LA was higher (52.65%) than that of the control (4.30%). The FRAP value of the sample was 12.85%, however, no activity was found in control. The inhibition effect of tyrosinase showed also a higher value (26.29%) when compared to the control. The results indicate that GA-LA, which showed superior antioxidative and skin-whitening activities in cream-based emulsion, is a useful functional material applicable in cosmetic products as well as food.