• Biomolecules & Therapeutics
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• v.25 no.4
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• pp.411-416
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• 2017

Paclitaxel (PTX) is a effectively chemotherapeutic agent which is extensively able to treat the non-small cell lung, pancreatic, breast and other cancers. But it is a practically insoluble drug with water solubility less than $1{\mu}g/mL$, which restricts its therapeutic application. To overcome the problem, hyaluronic acid-complexed paclitaxel nanoemulsions (HPNs) were prepared by ionic complexation of paclitaxel (PTX) nanoemulsions and hyaluronic acid (HA) to specifically target non-small cell lung cancer. HPNs were composed of ${\small{DL}}-{\alpha}$-tocopheryl acetate, soybean oil, polysorbate 80, ferric chloride, and HA and fabricated by high-pressure homogenization. The HPNs were $85.2{\pm}7.55nm$ in diameter and had a zeta potential of $-35.7{\pm}0.25mV$. The encapsulation efficiency was almost 100%, and the PTX content was 3.0 mg/mL. We assessed the in vivo antitumor efficacy of the HPNs by measuring changes in tumor volume and body weight in nude mice transplanted with CD44-overexpressing NCI-H460 xenografts and treated with a bolus dose of saline, $Taxol^{(R)}$, PTX nanoemulsions (PNs), or HPNs at a dose of 25 mg/kg. Suppression of cancer cell growth was higher in the PN- and HPN-treated groups than in the $Taxol^{(R)}$ group. In particular, HPN treatment dramatically inhibited tumor growth, likely because of the specific tumor-targeting affinity of HA for CD44-overexpressed cancer cells. The loss of body weight and organ weight did not vary significantly between the groups. It is suggest that HPNs should be used to effective nanocarrier system for targeting delivery of non-small cell lung cancer overexpressing CD44 and high solubilization of poorly soluble drug.

• Journal of the Korean Chemical Society
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• v.31 no.1
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• pp.110-117
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• 1987

For the preparation of linear low density polyethylene (LLDPE), the copolymerization of ethylene and 1-butene was carried out with various catalysts of titanium alkoxidealkylaluminum compound in slurry phase. The effects of catalyst components, aging time, concentration of catalyst components, polymerization time and temperature on the catalytic activity and copolymer composition were examined. The properties of copolymer obtained were also considered with the correlation to the 1-butene contents. It has been found that the titanium tetra-n-butoxide-diethylaluminum chloride catalyst system was the most suitable for the production of LLDPE with higher catalytic activity, more 1-butene content and less soluble parts. The density, glass transition temperature, melting point and heat of fusion of copolymer were decreased with increasing 1-butene contents.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.2
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• pp.227-236
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• 1995

The objective of this research was to characterize fucoidans isolated from Laminaria religiosa and Undaria pinnatifida in Korea to obtain basic data for Production of soluble dietary fiber materials with biological functionality. Fucoidans were successively extracted 3 times at $65\%$ for 1hr with arid solution of pH 2.0, and cetylpyridinium chloride was used for partial purification. The yields of partially purified fucoidans were $2.71\%$ for L. religiosa, $6.65\%$ for sporophylls of U. pinnatifida and $0.40\%$ for blade of U. pinnatifida. The yield from sporophylls of U. pinnatifida was highest among the sample tested, whereas the yield from blade of U. pinnatifida was lowest. It appeared that the fuconidans content in different parts of U. pinnatifida varied. Partially purified fucoidans were separated into 3 fractions by DEAE-Sephadex A-25 ion exchange column and the maior fractions were refractionated with tractional precipitation with ethanol. $60-70\%$ ethanol precipitated fractions of 1. religiosa and sporophylls of U. pinnatifida turned out to be homogeneous by cellulose acetate electrophoresis and gel filteration chromatography. The molar ratios of fucose, galactose, and sulfate in the purified fucoidans(ethanol precipitated fractions) were 1 : 0.31 : 2.43 for L. religiosa and 1 : 0.97 : 1.99 for sporophylls of U. pinnatifida. The averaged molecular weights of the purified fucoidans from L. religiosa and sporophylls of U. pinnatifida were 31,000 and 38,000, respectively.

• Food Science and Preservation
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• v.16 no.4
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• pp.499-505
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• 2009

Quality changes in fresh-cut potatoes during storage at $4^{\circ}C$ after treatment with low-temperature blanching and antibrowning agents were studied. Fresh-cut potatoes were treated by dipping for 1.5 min in a browning inhibitor solution containing 0.5% (w/v) ascorbic acid, 0.5% (w/v) citric acid, 0.5% (w/v) sodium chloride, 0.1% (w/v) trehalose, and 0.005% (w/v) biotin, at $60^{\circ}C$, with subsequent cooling for 1.5 min and storage at $4^{\circ}C$. The browning properties of fresh-cut potatoes were examined by measurement of polyphenol oxidase (PPO) activity and total phenolic content. Changes in quality attributes over a 14-day period were assessed in terms of titratable acidity, pH, water-soluble solid level, and gas analysis at $4^{\circ}C$. During storage, PPO activity increased, with the lowest activity seen after about 7 days of storage. Treatment with antibrowning solution at $4^{\circ}C$ increased visual sensory attributes during storage. Low-temperature blanching in distilled water more effectively inhibited browning compared with exposure to browning inhibitor solution, as assessed after 7 days of storage. Fresh-cut potatoes respired aerobically after different treatments during storage at $4^{\circ}C$.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.98-107
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• 2007

Most of plastic film house plots in Korea have salinity problems caused by salt accumulations associated with continuous cropping including the heavy applications of chemical fertilizers, and high evapotranspiration. The objective of this study was to investigate soil properties and watermelon (Citrullus lanatus Thunb.) productivity in plastic film houses as influenced by the short-term crop rotation in the continuous watermelon-cultivated soils. The short-term rotational crops selected were corn, Chinese cabbage, radish, young radish, lettuce, spinach, and onion. Soil pH increased in most plots where a short-term crop was added to the crop rotation, except where radish was added. The content of soil organic matter significantly decreased in the lettuce-cultivated plot. The available phosphorus content in the soils increased with the cultivations of spinach and onion. Exchangeable Ca and Mg tended to increase in most of plots where a short-term rotational crop was grown, whereas the exchangeable K was clearly reduced by more than 50% in the same plots. Cultivation of rotational crops during the post-harvest season significantly decreased the electrical conductivity (EC) and the concentrations of soluble anions, such as chloride ($Cl^-$), nitrate ($NO_3{^-}$), and sulfate ($SO{_4}^{2-}$) in the soils. In particular, the EC decrease was related with the decrease in soil $K^+$ to $Ca^{2+}$ and $Mg^{2+}$ ratio. In all plots cultivated with the shot-term rotational crops, the ratios of bacteria to fungi (B/F) increased. However, the improvement in soil properties after adding a rotational crop did not result in a clear improvement in watermelon quantity or quality as measured by fruit weight and sugar content. Therefore, the addition of short-term rotational crops to a continuous watermelon cropping system would be beneficial to improve target soil properties in plastic film house plots studied.

• Journal of Bio-Environment Control
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• v.18 no.4
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• pp.436-441
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• 2009

The experiment was conducted to investigate the effect of nitrogen and potassium sources on growth and yield of strawberry 'Seolhyang' and 'Maehyang' in fertigation culture. The plant fresh and dry weight were higher in urea + potassium sulfate and ammonium sulfate + potassium sulfate as nitrogen and potassium sources than others in both varieties. But there were no significant difference among nitrogen and potassium sources in other growth characteristics, such as plant height, no. of leaf, crown diameter etc. Also, the marketable yield of fruit were higher in urea + potassium sulfate and ammonium sulfate + potassium sulfate in 'Seolhyang' than other treatments. 'Maehyang' was better in both treatments but there was no significant difference. The fruit qualities, such as total soluble solid, hardness, acidity, vitamin C content were not significant difference among the treatments. The acidity of soil was tended to decrease but EC was tended to increase highly in ammonium sulfate treatments as a nitrogen source. As above results, the urea and potassium sulfate were recommended as nitrogen and potassium sources for the fertigation culture of strawberry 'Seolhyang' and 'Maehyang'.

• Korean Journal of Microbiology
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• v.53 no.3
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• pp.200-207
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• 2017

A new approach to the solubilization of waste activated sludge (WAS) using alginate-quaternary ammonium complex beads was investigated under controlled mild alkaline conditions. The complex beads were prepared by the reaction of sodium alginate (SA) with 3-(trimethoxysilyl)propyl-octadecyldimethylammonium chloride (TSA) in acid solution, followed by crosslinking with $CaCl_2$. Treatment of WAS with SA-TSA complex beads was effective for enhancing the efficacy of WAS solubilization. The highest value of soluble chemical oxygen demand (SCOD) concentration (3,900 mg/L) was achieved after 10 days of treatment with 30% (v/v) SA-TSA complex beads. The WAS solubilization efficacy of the complex beads was also evaluated by estimating the concentrations of volatile fatty acids (VFAs). The maximum value of VFAs was 2,961 mg/L, and the overall proportions of VFAs were more than 75% of SCOD. The main components of VFAs were acetic, propionic, iso-butyric, and butyric acids. These results suggest that SA-TSA complex beads might be useful for enhancing the solubilization of WAS. The potential use of VFAs as the external carbon substrate for the production of polyhydroxyalkanoate (PHA) by a mixed microbial culture (MMC) was also examined. The enrichment of PHA-accumulating MMC could be achieved by periodic feeding of VFAs generated from WAS in a sequencing batch reactor. The composition of PHA synthesized from VFAs mainly consisted of 3-hydroxybutyrate. The maximum PHA content accounted for 25.9% of dry cell weight. PHA production by this process is considered to be promising since it has a doubly beneficial effect on the environment by reducing the amount of WAS and concomitantly producing an eco-friendly biopolymer.

• Journal of the Korea Concrete Institute
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• v.17 no.3 s.87
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• pp.411-418
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• 2005

Polymer-modified mortar and concrete are prepared by mixing either a polymer or monomer in a dispersed, or liquid form with fresh cement mortar and concrete mixtures, and subsequently curing, and if necessary, the monomer contained in the mortar or concrete is polymerized in situ. Although polymers and monomers in any form such as latexes, water-soluble polymers, liquid resins, and monomers are used in cement composites such as mortar and concrete, it is very important that both cement hydration and polymer phase formation proceed well the yield a monolithic matrix phase with a network structure in which the hydrated cement phase and polymer phase interpenetrate. In the polymer-modified mortar and concrete structures, aggregates are bound by such a co-matrix phase, resulting in the superior properties of polymer-modified mortar and concrete compared to conventional mortar and concrete. The purpose of this study is to obtain the necessary basic data to develope appropriate latexes as cement modifiers, and to clarify the effects of the monomer ratios and amount of emulsifier on the properties of the polymer-modified mortars using methyl methacrylate-butyl acrylate(MMA/BA) and methyl methacrylate-ethyl acrylate(MMA/EA) latexes. The results of this study are as follows, the water absorption, chloride ion penetration depth and carbonation depth of MMA/BA-modified mortar are lowest. However, they are greatly affected by the polymer-cement ratio rather than the bound MMA content and type of polymer.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.319-327
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• 1981

In order to reproduce and improve the Korean traditional Kochujang(fermented hot pepper-soybean paste), traditional and improved Kochujang Koji were prepared according to the standard method investigated in Chunrabookdo area and combined the raw materials of Kochujang by the traditional habit. Amino nitrogen contents were higher in improved Kochujang than in traditional one, those were in the range from 83 to 106 mg% immediately after brewing and 191 to 313 mg% at the end stage of brewing. Water soluble and ammonia nitrogen contents were most high in the improved Kochujang which was mixed with sodium chloride and brewed soysauce as seasoning. The content of reducing sugar of traditional Kochujang was higher than that of improved one during the brewing. Ethyl alcohol contents of all Kochujang samples were 0.04% at the early stage of brewing and that reached above 2.5% after $40{\sim}50$ days brewing.

• Applied Biological Chemistry
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• v.20 no.2
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• pp.221-227
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• 1977

Contents of proline and chloride in halophytes were $80-1700\;{\mu}g/gfw$ and 0.13-0.45 mM/gfw respectively. The content of proline was inversely proportional to that of chloride. Rhizomes of Phargmites communis Trin, a halophyte, were grown in non-saline medium and then taken to saline treatment for one or two weeks. Growth of P. communis was inhibited when salinized with 0.25M NaCl. Total nitrogen decreased and alcohol soluble nitrogen and proline increased when growth was retarded. The quantity of Fraction 1 protein decreased at 0.25M NaCl treatment. The accumulation of proline at high concentration in P. communis suggested that it might play a role in osmotic adjustment.