• Journal of Pharmaceutical Investigation
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• v.40 no.6
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• pp.373-378
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• 2010

In order to develop a topical preparation which has a high occlusive property with skin moisturization, nano-structured lipid carrier (NLC) systems along with solid lipid nanoparticle (SLN) were designed. Various NLC dispersions were successfully formulated with Compritol 888 ATO as a solid lipid, Labrafil M 1944 CS as an oil, and Tween 80 as a surfactant. The increase of oil content (5 to 50%) led to the decrease in the occlusion factor in the order of SLN > NLC-5 > NLC-15 = NLC-30 > NLC-50. Particle size of lipid particulates was in the range of 100 to 160 nm. NLC-based carbogels were prepared by the employment of humectants such as urea, glycerin, and Tinocare GL to carbomer gel. NLC-30 gel formulations containing 4 or 8 % of lipid particles showed improved occlusive effect in vitro, compared to NLC-free gel base. Even though NLC-free gel base revealed comparable occlusion effect by itself, the occlusion factor of 4 % NLC-30 gel was about 2-fold higher than that of NLC-free gel base.

• Journal of Pharmaceutical Investigation
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• v.27 no.3
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• pp.199-205
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• 1997

In order to formulate biphenyl dimethyl dicarboxylate(DDB) aqueous solutions, the effects of various solubilizing agents such as cosolvents(PG, PEG 400, glycerin, ethanol), surfactants,$(poloxamer\;407,\;Cremophor^{\circledR}\; RH40,\;Solutol^{\circledR},\;Tween\;80,\;sodium\;lauryl\;sulfate)$, complexation agent$(CELDEX^{\circledR}\;CH-20)$ and others(urea, niacinamide, propylene carbonate, HPMC) on the solubility of DDB in water were evaluated. The solubility of DDB in water was about $0.21\;{\mu}g/ml\;at\;20^{\circ}C$, while its solubility in PEG 400 was 5,000 times higher than that in water. 60% PEG 400 aqueous solution was selected as an optimum solvent system, and surfactants or other solubilizing agents were added to prevent DDB from recrystalization. The addition of surfactants in water increased the solubility of DDB from 15- to 34-fold, however, $CELDEX^{\circledR}\;CH-20$ and other agents studied showed negligible effects on the solubility of DDB in water. The 60% PEG 400 aqueous solution containing 5% $Cremophor^{\circledR}$　RH40 was appeared as the formula of choice. It showed acceptable physical stability after stored for 7 days at $4^{\circ}C$.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.12 s.148
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• pp.1546-1553
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• 2005

The wetting behavior and liquid transport of nonionic surfactant solutions; Span 20 and Tween 20, 40, 60, 80, 21, 61, 81, 65 & 85: in polyethylene terephthalate(PET) fabrics are reported. Five different PET fabrics are used in this study. PET 1, 2 & 3 have different compactness in structure. PET 4 & 5 have similar physical properties to PET 2, however, PET 4 has heat set finish and PET 5 with rewetting agent. The wetting and water retention properties of PET fabrics are greatly improved by addition of nonionic surfactants. The aqueous liquid retention(W) vs. cosq and W vs. adhesion tension has positive linear relationship. Hydrophilic surfactants which have short hydrophobes and surfactants with unsaturated hydrophobe structures are more efffctive in improving the wetting properties of PET fabrics. PET fabric which has larger thread spacing shows greater value of water retention ratio(W/H) than PET fabric with smaller thread spacing if there are no surfactants present in the system, however, W/H values become very similar among these PET fabrics when the surfactants are added. If there are no surfactants present in the system, PET with heat set finish has smaller value and PET with rewetting agent has greater value of W/H than PET without finish even though the fabrics have the similar physical properties.

• Clean Technology
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• v.11 no.1
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• pp.1-12
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• 2005

In these studies, semibatch emulsion copolymerization of n-butyl acrylate (n-BA) as adhesive component and methyl metacrylate (MMA) as coagulant component was carried out in order to investigate the role of surfactant in aqueous phase for polymer cement. It was found that the particle size and concentration of final polymer are affected by surfactant type used. The effect of nonionic surfactants was shown in the decrease of polymer emulsion concentration and small emulsion particle in order of LE-50, NP-50 > CE-50, Tween 20 > TX-405 > Brij 35. In LE and NP (n=7-50) as nonionic surfactant, it could be obtained the stable polymer emulsion of 40% in aqueous phase with average particle size of 250-320 nm using over n=30. On the other hand, the effect of surfactant type in initial reactor charge was shown that when SDS as ionic surfactant was used, the polymer emulsion concentration was constant irrespective of the amount used, whereas CTAB as cationic surfactant and HN-100 as reactive surfactant were shown a tendency to the decrease of that. The effect surfactant type on final polymer particle size was shown in decrease by the order of SDS > CTAB > HN-100.

• Applied Biological Chemistry
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• v.35 no.4
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• pp.237-241
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• 1992

The protease from Halomonas sp. ES 10 was purified by methanol precipitation, gel filtration on Sephadex G-150 and G-200, and ion exchange chromatography on DEAE-Sephadex A-50. The purified enzyme was found to be homogeneous by polyacrylamide gel electrophoresis. The specific activity of purified enzyme was 1,014 units/mg protein, and the yield of the total activity from the culture filtrate was 7%. The optimal temperature and pH for the enzyme activity were $35^{\circ}C$, and pH 11.0, respectively. And the enzyme was stable in the range of $pH\;7.5{\sim}11.0$. The residual activity of the enzyme was 70%, when the enzyme was incubated at $50^{\circ}C$ for 40 min. The Km value of the enzyme was 7.4 mg/ml to milk casein. $Li^+$, $Ca^{2+}$, SDS and Tween 80 were appeared to activators, whereas $Hg^{2+}$ and EDTA to inhibitors. The addition of DFP and PMSF showed the relative enzyme activities of 63% and 107%, respectively, suggesting that the enzyme may not belong to serine type protease. When the alkaline protease was treated with 0.5 M and 1 M NaCl, the relative enzyme activities were 95% and 65%, respectively. This enzyme showed 20% and 15% higher enzyme activity than that of Aspergillus oryzae (Sigma Chemical Company product, P4755) in the presence of 0.5 M and 1 M NaCl.

• KSBB Journal
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• v.14 no.4
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• pp.445-451
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• 1999

Glutathione production was carried out using mixed cells of E. coli TG1/pDG7 $\alpha$ and bakers yeast in an Aerated Slurry Bioreactor. Glutathione-producing enzymes were stable for 34 hours, yielding 4.6 mM glutathione in suspension reaction. Glutahione production with high density mixed cells was studied as a function of flow rate in an Aereated Slurry Bioreactor. Glutathione concentration was higher than that in suspension reaction for 32 hours at the substrate feeding rate of 5.2 mL/hr with cell recycle in continuous Aerated Slurry Bioreactor. It was for 42 hours at 2.6 mL/hr and 22 hours at 5.2 mL/hr without cell recycle. Glutahione productivity was 25.7 mg/g wet $cell{\cdot}hr$ at the substrate feeding rate of 10.4 mL/hr with cell recycle, but 5.28 mg/g wet $cell{\cdot}hr$ at 5.2 mL/hr and 1.65 mg/g wet $cell{\cdot}hr$ at 2.6 mL/hr without cell recycle. Effective production time increased from 25 to 45 hours, by using a surfactant, tween 80. As a purfing gas, nitrogen was tested instead of air to avoid a possible oxidizing effect on glutathione-producing enzymes, resulting in the increase of effective production time to 40 hours.

• BMB Reports
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• v.40 no.1
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• pp.100-106
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• 2007

The wound-inducible lipoxygenase obtained from maize is one of the nontraditional lipoxygenases that possess dual positional specificity. In this paper, we provide our results on the determination and comparison of the kinetic constants of the maize lipoxygenase, with or without detergents in the steady state, and characterization of the dependence of the kinetic lag phase or initial burst, on pH, substrate, and detergent in the pre-steady state of the lipoxygenase reaction. The oxidation of linoleic acid showed a typical lag phase in the pre-steady state of the lipoxygenase reaction at pH 7.5 in the presence of 0.25% Tween-20 detergent. The reciprocal correlation between the induction period and the enzyme level indicated that this lag phenomenon was attributable to the slow oxidative activation of Fe (II) to Fe (III) at the active site of the enzyme as observed in other lipoxygenase reactions. Contrary to the lagging phenomenon observed at pH 7.5 in the presence of Tween-20, a unique initial burst was observed at pH 6.2 in the absence of detergents. To our knowledge, the initial burst in the oxidation of linoleic acid at pH 6.2 is the first observation in the lipoxygenase reaction. Kinetic constants (Km and kcat values) were largely dependent on the presence of detergent. An inverse correlation of the initial burst period with enzyme levels and interpretations on kinetic constants suggested that the observed initial burst in the oxidation of linoleic acid could be due to the availability of free fatty acids as substrates for binding with the lipoxygenase enzyme.

• Applied Biological Chemistry
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• v.47 no.2
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• pp.170-175
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• 2004

In this paper we studied about Bacillus sp. TBM40-3 producing biosurfactants. The strains were isolated from Taeback Mountain soil and identified as Bacillus sp. by l6S rDNA nucleotides sequence analysis. The TBM40-3 was gram-positive and rod-shaped as observed by field emission scanning microscopy. After the cultivation TBM40-3 in LB broth for 90 h and the surface tension of supernatant was decreased to 29 mN/m. Emulsification activity and stability of crude biosurfactant was measured by using water-immiscible hydrocarbons and oil as substrate. Maximum emulsification activity and stability was obtained from soybean oil. Also, we confirmed that the TBM40-3 producing biosurfactant had an effect on crude oil while showing a superior effect as compared to chemically synthesized surfactants (SDS, Span85, Tween40, Triton X-100). As a result, the Bacillus sp. TBM40-3 producing biosurfactant had potent properties as an emulsifying agent and an emulsion stabilizing agent.

• Journal of Animal Science and Technology
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• v.48 no.6
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• pp.839-846
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• 2006

This study was conducted to evaluate the effects of dietary addition of sucrose, propylene glycol and Tween 80 (Polysorbate 80 : Non-ionic Surfactants) on pre-partum (21 d) and post-partum (21 d) nutrients intake, blood metabolites, occurrence of metabolic disorders, milk yield and its composition in Holstein cows. Two basal diets were formulated each for pre- and post-partum period. The diets were mixed daily and fed at ad libitum to transitional cows. Forty cows of similar parity and milk yield were randomly divided into four groups (ten animals in each). The cows in three groups were supplemented either with 280g of sucrose/day (SU), SU+64g propylene glycol/day (SUP) or SUP+50g Tween80/day (SUPT). The feed for the fourth group was not supplemented and this group served as control (C). Pre-partum DM, total digestible nutrients (TDN), and crude protein (CP) intake was similar in cows fed C, SU, SUP, and SUPT diets. Post-partum DM, TDN, and CP intakes were the highest with SUPT diet followed by SU, SUP and control diets. Pre-partum blood non-esterified fatty acids (NEFA) concentration was noticed significantly higher in cows fed control diet compared to those fed SU, SUP and SUPT diets. The concentration of NEFA was similar at calving and during post-partum period across cows fed different experimental diets. Blood glucose and Ca concentration during pre- and post-partum periods were not significantly different in cows fed C, SU, SUP and SUPT diets. Milk yield (kg/day) was similar in cows fed different experimental diets. However, milk fat percent and 4% fat corrected milk yield were higher in cows fed SU diet (p<0.05) followed by SUP, SUPT and C diets. One case of ketosis was recorded in cows fed control diet however its occurrence was not observed in cows fed other diets. Occurrence of retained placenta and mastitis was numerically higher in cows fed control diet compared with those fed SU, SUP and SUPT diets. In conclusion, the NIS and propylene glycol feeding along with sucrose could improve the 4% fat corrected milk and fat yield in early lactating cows with significant reduction in NEFA and metabolic disorders during transitional period.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.255-262
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• 2002

This experiment was performed to improve the stability of Lactobacillus fermentum YL-3 as a poultry probiotics. The culture conditions that improve acid tolerance of L. fermentum YL-3 were investigated by changing several factors such as medium composition, temperature, anaerobic incubation and culture time. Also, L. fermentum YL-3 was encapsulated with alginate, calcium chloride and chitosan. The stable culture conditions of L. fermentum YL-3 were obtained in anaerobic incubation using MRS media without tween 80 for 20 hour at $42^{\circ}C$. The capsule after treatment with 1% chitosan was formed close membrane by a bridge bond. Immobilization of L. fermentum YL-3 in capsule was observed by confocal laser scanning microscopy, and cell viability was $2.0{\times}10^9\;CFU/g$ above the average. L. fermentum YL-3 capsule after acid treated at pH 2.0 for 3 hour survived about 40%, but those encapsulated with 1% chitosan survived about 65%. Survival rate of capsule stored at room temperature decreased about $2{\sim}3$ log cycle during 3 weeks, but viability of capsule stored at $4^{\circ}C$ during 3 weeks maintained almost $10^8\;CFU/g$ levels.