• YAKHAK HOEJI
• /
• v.41 no.3
• /
• pp.305-311
• /
• 1997

Sustained release-microspheres and immediate release-pellets were prepared to develop a controlled release multiparticulate system containing both water soluble and insoluble dr ug. Pseudoephedrin.HCl (EPD) and terfenadine (TRF) were used as model drugs, respectively. Sustained release-EPD microspheres were prepared by solvent evaporation method using Eudragit RL or RS as a matrix combined with pH-insensitive film coating. Smaller EPD microspheres were obtained when smaller amount of Eudragit as a matrix material or larger amount of magnesium stearate as a dispersing agent was used. However the obtained microspheres did not show syfficient sustained release characteristics. About 97% of EPD was released after 1 hr irrespective of matrix material used. Subsequent coating of the microspheres with pH-insensitive polymer such as Eudragit RS or ethylcelulose (EC) resulted good sustained in 37.5, 73.3 and 92.0% release of encapsulated EPD in distilled water after 1, 3 abd 7 hr, respectively. It corresponds to mean dissolution time (MDT) of 2.3 hr, which is much larger than that of un-coated EPD microspheres (0.0048 hr). Immediate release TRF pellets were prepared by spherically agglomerated crystallization using Eudragit E as an inert matrix and methylene chloride as a liquid binder. Using Eudragit E alone as a matrix resulted in satisfactory physical properties of the pellets such as sphericity, surface texture and flowability, but led to slower release of TRF from pellets than un-modified TRF powder (MDT of 1.70 vs 1.43 hr in pH 1.2 dissolution medium). Introducing propylene glycol or sodium lauryl sulfate as an emulsifier brought about faster release of TRF from pellets (MDT of 1.14 and 0.95 hr, respectively). In conclusion, microencapsulation by solvent evaporation combined with film coating and spherically agglomerated crystallization were successfully utilized to prepare controlled release multiparticulate system composed of sustained release EPD-microspheres and immediate release TRF pellets.

• Food Science and Preservation
• /
• v.13 no.3
• /
• pp.285-291
• /
• 2006

The effects of sorbitol mixture as plasticizers on moisture sorption property (MSP), water vapor permeability (WVP), color, tensile strength (TS), elongation at break (E), and total soluble matter (TSM) of soy protein isolate (SPI) films were investigated. Two different types of sorbitols, aqueous and crystalline, were added to film-forming solutions in various ratios of crystalline to aqueous (0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25, or 1:0, based on weight). In addition, the characteristics of the SPI films plasticized by sorbitol mixtures and glycerin were compared with moisture sorption rate against time. Sorbitol-plasticized films had higher in TS, but lower in WVP and E than the glycerin-plasticized films. However the properties of SPI films did not differ appreciably by the type of sorbitol added to film-forming solutions. To explain the high solubility and low WVP of sorbitol-plasticized films, cumulative amounts of moisture content gained during adsorption and lost during desorption of films were compared between sorbitol and glycerin-plasticized films. The result suggest that use of sorbitol as a plasticizer for preparing SPI films improves moisture barrier properties of the films. However the high solubility of sorbitol-plasticized films needs to be reduced for improving the functionality of SPI films in potential packaging applications.

• Korean Journal of Food Science and Technology
• /
• v.34 no.6
• /
• pp.1036-1042
• /
• 2002

During storage at $25^{\circ}C$, the effect of gas absorbents, such as carbon dioxide scavenger, ethylene absorber, and their combinations, on respiration characteristics and quality attributes of mature-green Mume fruits packaged in $30\;{\mu}m$ low density polyethylene (LDPE) film was examined. Changes in quality attributes of the fruits were observed in terms of weight loss, titratable acidity, pH, fish firmness, color, water-soluble solid, and chlorophyll contents. In the presence of ethylene absorber $(KMnO_4)$, the physiological injury was remarkably suppressed, and there was no significant injury in Mume fruits at $25^{\circ}C$ for 10 days. Yellowing and softening were also noticeably reduced by the combination of plastic film packaging and inclusion of ethylene absorber. The respiration rate was slower in fruits sealed with ethylene absorber than in those with absorbent-free packaging. Using ethylene absorber, levels of oxygen and carbon dioxide were maintained at 2-3 and 7-8%, respectively, during storage at $25^{\circ}C$ for 10 days. The addition of carbon dioxide scavenger $(Ca(OH)_2)$, negatively affected the quality attributes and respiration characteristics of the fruits. Overall results showed that ethylene removal by gas absorbent in the film packages significantly prolonged the shelf life of the fruits at ambient temperature.

• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.4
• /
• pp.234-241
• /
• 2000

Organic farming (OF) is regarded as alternative farming types against general farming system for sustainable agriculture, recently. However, there is little information on effects of OF on soil properties and watershed condition. In order to determine the effects of OF on soil properties, 36, 10 and 8 sites of organic farming (OF) fields of plastic film houses, paddy and orchard were selected in the national scale, respectively, to evaluate their chemical properties and phosphorus distributing characteristics. The average organic matter (OM) contents in organic farming fields were with $44g\;kg^{-1}$ in plastic film houses, $26g\;kg^{-1}$ in paddies and $39g\;kg^{-1}$ in orchard soils higher than the average OM contents in conventional farming (CF) soils. Available phosphates were accumulated to 986 in plastic film house soils and $754mg\;kg^{-1}$ in orchard soils, respectively, over the optimum range. Furthermore, total P (T-P) reached to $2.973mg\;kg^{-1}$ in plastic film houses and $2303mg\;kg^{-1}$ in orchards in OF soils. It could be attained by applying repeatedly low N/P ratio of manure-based compost. In two types of soils inorganic P was dominant with the ratio of 62~80% of T-P, and then residual and organic Ps followed. However. residual-P was dominant in paddy soils with the rate of 50% of T-P. Fractionation of soil extractable P showed that Ca-P was dominant with about $1,330mg\;kg^{-1}$ in upland soils in OF fields, which is affected by high soil pH of over 6.0. However. Fe-P of extractable P was dominant in paddy soils. Water-soluble P was very high with 65 and $26mg\;kg^{-1}$ in plastic film house and orchard soils in OF. From this results. OF regarded as an environment-friendly farming system may cause serious soil deterioration by accumulated phosphorus and may also cause water pollution.

• Journal of Soil and Groundwater Environment
• /
• v.6 no.2
• /
• pp.3-13
• /
• 2001

It has been known that nonlinear characteristics of sorption affect the transport behavior of water soluble pollutants in soils. However detailed experimental studies have not been performed to verify the effect of non-linearity of adsorption isotherm on transport of chemicals in porous media. In this research, the distortion of breakthrough curves of a cationic surfactant (cetylpyridinium chloride, CPC) in a engineered stainless steel column packed with glass beads were investigated. Glass beads with about 110 $\mu\textrm{m}$diameter coated with a thin n-decane film were used as the media providing the sorption surface for CPC. The CPC adsorption isotherm on the surface of n-decane from aqueous solution was a typical Langmuir type. The breakthrough curve of CPC using step Input showed a late breakthrough on the front side and early breakthrough on the back side accordance to the shape of the isotherm. The retardation factor of CPC was found to be a strong function of the input concentration, which also a manifestation of the non-linearity of the isotherm. The retardation factors for the CPC with step input agreed with those of pulse input that the maximum concentrations are controlled to be the same as the step input concentrations. This results support the validity of the unproven field practices of using hydrogeotracers with non-linear adsorption isotherms to determine the hydrogeological parameters, e.g., NAPL saturation, air-water or NAPL-water interfacial areas.

• Korean Journal of Soil Science and Fertilizer
• /
• v.37 no.2
• /
• pp.91-96
• /
• 2004

Accumulation of nitrate in edible crops is undesirable due to potential risks to human health. Since nitrate has a role in the osmotic regulation of plants, salt accumulation in soil is expected to stimulate nitrate accumulation in plants. Lettuce (Lactuca sativa L.) was grown in soils of different salinities, 9.69 and $4.49dS\;m^{-1}$, in a greenhouse, and the effect of soil salinity on nitrate accumulation in lettuce was investigated. Content of nitrate in the lettuce increased significantly as soil salinity increased under low light intensity and ample supply of nitrate in root media. Soluble sugar and oxalate contents in lettuce were also significantly higher in the soil of higher salinity. Phosphate, Cl, and $SO_4$ contents in lettuce were not significantly different in soils of different salinities. Among the cations, K content in lettuce was significantly higher in the soil of higher salinity, but Na, Ca, and Mg comtents were not much influenced. Comparing to the lettuce grown in low salinity soil, although the growth of lettuce was decreased by 9% in the soil of higher salinity, nitrate accumulation in the lettuce was increased by 18.6%. These results indicate that higher nitrate content in lettuce of higher salinity soil is a positive accumulation to adapt to the water stress condition. The nitrate accumulation of vegetables grown in plastic film houses is known to be due to the heavy fertilization and low light intensity, but salt accumulation in the soil, which can lower soil water potential, is expected to stimulate the nitrate accumulation further.

• Korean Journal of Food Science and Technology
• /
• v.33 no.4
• /
• pp.469-473
• /
• 2001

Fuji apples were sliced and dipped in distilled water, 1% (w/v) ascorbic acid and 1% (w/v) oxalic acid. After minimal processing, the slices were packaged with three films which have different gas transmission rate and stored in cold room$(0-2^{\circ}C)$. The visual quality, gas composition, pH, texture, soluble solids content and titratable acidity were determined. The most deteriorative effects on quality were produced by browning of flesh. Ascorbic acid inhibited the development of browning and extended storage life from 7 days of control to 14 days at $0-2^{\circ}C$. Minimally processed Fuji apple treated with ascorbic acid and P640 film showed exhausting of oxygen in the packaging after 14 days. It showed only a slight reduction of pH from 3.73 to 3.72. The visual quality, gas composition, pH, texture, soluble solids content, titratable acidity were slightly changed, indicating that higher quality was maintained during storage. Ascorbic acid inhibited the development of browning and extended storage life of fresh-cut Fuji apple.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.9 no.2
• /
• pp.85-92
• /
• 2007

This study focused on bean-juice treatment method which have dyeing property to indigo, yellow soil, sappan wood, cochineal and also on the possibility of applying to mordanting. This is different from the active mordanting using chemicals. Natural mordants with development of dyeing are not harmful, also are the medicines for disease. Limestone and ash neutralize the acidic soil. bean-juice protein adhere to cellulose surface and change the physical properties of protein so that coloring of dye is better than before and film non-soluble in water is made. Therefore the color made from bean-juice process lasts after washing. This study try to show one of the ways to improve the current method using the heavy metal which can have bad effects for environment and human being. Bean-juice(raw bean, heated bean) treatment method can be the way to fix the natural dyeing problem of bad dyeing. Bean-juice had been treated under various condition with pre-treatment, post-treatment and raw bean, heated bean. Following results are obtained in this study. In the case of Indigo dyeing, pre-treatment of heated bean shows the biggest difference of color. In the case of yellow soil dyeing, pre-treatment of raw bean-juice shows the biggest gap of color. Pre-treatment of heated bean in sappan wood dyeing case and post-treatment of raw bean show bigger color difference than pre-treatment of raw bean. In cochineal dyeing, raw bean pre-treatment shows the biggest color difference.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.49 no.1
• /
• pp.67-74
• /
• 2023

In this study, for a natural cosmetics market, we sought to explore alternatives that can replace polyvinyl alcohol (PVA) of peel-off packs. A peel-off type pack was prepared by combining pullulan, a water-soluble polysaccharide, and other polysaccharides (sodium hyaluronate, cellulose gum, hydroxyethyl cellulose, sodium alginate, corn starch), and the pH, viscosity, and stability against temperature of each peel-off type pack were confirmed. The thickness and tensile strength of the manufactured film were measured for comparison with the PVA peel-off type pack, and applicability, drying speed, and removal degree were measured. Among them, the pullulan-sodium hyaluronate peel-off type pack showed excellent film formation ability to replace the peel-off type pack containing PVA with 5.12% thin film thickness and 4.23% high film tensile strength. When applied to actual skin, the degree of spread of the pack, the usability that can be uniformly applied, and the formation and removal strength of the film when removed after drying were also similar to the peel-off type pack containing PVA. Therefore, it was confirmed that the film formed of pullulan-sodium hyaluronate showed enough physical properties to replace the PVA of the peel-off type pack as a natural peel-off type pack.

• Food Science and Preservation
• /
• v.20 no.2
• /
• pp.166-172
• /
• 2013

The effect of phytoncide solution treatment on the browning and quality of fresh-cut iceberg lettuce during storage was studied. The treatments were applied as four solutions adjusted at $10^{\circ}C$: distilled water (DW) as the control; edible ethanol (EE); 1% (v/v) phytoncide essential oil from pine needle diluted with distilled water (DP); and 1% (v/v) phytoncide essential oil diluted with edible ethanol (EP). Fresh-cut lettuce was dipped in each solution for 60 sec, was rinsed with distilled water, was packaged with an OPP film bag, and was then stored at $4^{\circ}C$ for 12 days. The EP group had a significantly high level of total soluble solids, titratable acidity, and carbon dioxide, and low total bacteria counts, pH, and oxygen. The sensory score of color in the EP group recorded a high value, but the EE and EP groups recorded low scores in aroma and taste during the storage period. Alcohol and phytoncide were vaporized by opening the package for two hours, and the score of the aroma and taste of EP showed no differences from those of the other groups. Based on the above results, it was determined that the phytoncide essential oil diluted in edible alcohol with 1% solution inhibited the browning of and microbial growth in fresh-cut lettuce, and will be a useful natural compound in maintaining the quality of fresh-cut produce.