• Journal of Microbiology and Biotechnology
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• v.11 no.2
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• pp.193-198
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• 2001

Preparation of antibacterial biopolymer film which is suitable for food packaging film was investigated using K-carrageenan as a base material. K-Carrageenan showed good biodegradability and film-forming characteristic but poor mechanical properties under humid condition. Also, various bacteria grew well on its surface. The poor mechanical properties could be improved by mixing with alginate at a 1:1 ratio and crosslinking with $CaCl_2$ solution. Antibacterial property coul be provided by modifying the K-carrageenan film surface with acrylic acid plasma followed by ion-exchange with $Ag^+$ ions. Such prepared film still showed good biodegradability by various fongi.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.277.2-278
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• 2002

Synthetic vectors have been considered as a safer and more versatile alternative to viral-based gene delivery systems. A variety of simple synthetic vector systems such as cationic lipid- and polymer-complexed plasmid DNA were shown to have a significant transfection activity in vitro but their use in vivo has been hampered by the decrease in transfection efficiency mediated by non-specific electrostatic interactions with serum components. (omitted)

• Korean Journal of Food Science and Technology
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• v.36 no.3
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• pp.432-439
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• 2004

Increase in water vapor barrier properties of sodium alginate films was studied by preparing composite films with fatty acids, i.e., lauric, palmitic, stearic, and oleic acids, and by treatment with 3% $CaCl_{2}$ solution for 3 min. Film thickness, surface color, microstructure, tensile strength (TS), elongation at break (E), water vapor permeability (WVP), water solubility (WS), and sorption isotherm of films were investigated. Microstructure of films observed with SEM was changed by fatty acid and $CaCl_{2}$ treatments. TS decreased 25-70% depending on fatty acid used, and increased 1.5- to 2-fold by $CaCl_{2}$ treatment. E decreased by both fatty acid and $CaCl_{2}$ treatments. Except oleic acid, WVP decreased significantly (p<0.05) by forming composite films with fatty acids, particularly with stearic acid, WVP decreased more than two-fold. WS also decreased by fatty acid and $CaCl_{2}$ treatments. In stearic acid, WS decreased about 30-fold by combined treatment of fatty acid and $CaCl_{2}$. Sorption isotherm showed typical biphasic pattern with deliquescent point of 0.75. Results of isotherms and BET monolayer moisture content indicated hydrophilicity of film decreased by $CaCl_{2}$ treatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.313-318
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• 1997

Effects of the concentration of NaCl, the concentration and the molecular weight of chitosan on the permeability of capsule type fertilizer and herbicide were investigated. The encapsulating process was based on the electrostatic interaction between chitosan (a polycationic polymer) and sodium alginate (an anionic polysaccharide). Sodium alginate solution $(1\%)$ was dropped into chitosan solution $(1\%)$ in which various amounts of NaCl was added. The capsule strength was increased with the addition of NaCl and the maximum value of capsule strength was observed at 0.3M NaCl. Capsule type fertilizer and herbicide were immersed in deionized water to determine its permeability, and it was affected by the concentration of NaCl and chitosan, and the molecular weight of chitosan. As the concentration of NaCl in chitosan solution increased, permeability of the capsule increased and marked the maximum value of $ 88\%$(fertilizer), $87\%$ (herbicide) at 0.75M NaCl. As concentration of chitosan solution increased, permeability tended to decreased; it showed the maximum value of $90\%$ (fertilizer) and $90.3\%$ (herbicide) at $0.25\%$ chitosan and the minimum value of $83\%$ (fertilizer) and $82\%$ (herbicide) at $1\%$ chitosan. Permeability of fertilizer and herbicide also decreased, as the molecular weight of chitosan (material of capsule) was decreased; it was showed $86\%$ (fertilizer) and $83\%$ (herbicide) at M.W 330,000 (sonication time 0min) and $52\%$ (fertilizer) and $51\%$ (herbicide) at M.W 119,000 (sonication time 180 min). The chitosan-alginic acid capsule was manufactured (defined as prepared capsule), dried for 6 hrs and immersed in deionized water (defined as restored capsule) to examine restoration of capsule. Restoration of capsule was good, and capsule strength was slightly decreased form $20g/cm^2$ (prepared capsule) to $17g/cm^2$ (restored capsule)

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.240-245
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• 1993

The optimum pH and temperature for the purified extracellular enzyme activity were 8.0 and 37$^{\circ}C$, respectively. NaCl was required for the activation of the enzyme and optimum concentration was 0.5M. This enzyme activity was inhibited by HgC $l_2$, CoC $l_2$ and ZnC $l_2$ and stimulated by CaC $l_2$. The activity of enzyme was increased by L-cysteine and 2-mercaptoethanol, but decreased by ο-phenanthroline, $\rho$-CMB, EDTA and iodoacetate. The $K_{m}$ and $V_{max}$ values of extracellular enzyme appeared as 0.717% and 15.39U/mg, respectively.y.

• Food Engineering Progress
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• v.21 no.1
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• pp.72-78
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• 2017

The objective of this study was to investigate the effects of combinations of tofu paste and non-starch polysaccharides (NSP) on the oil uptake reduction (OTR) of deep-fat fried cake doughnuts. OTR agents were tofu paste (from grinding tofu with deionized water, followed by passage through a 60 mesh sieve), and five neutral and nine anionic NSPs. A control doughnut (without tofu paste or NSP), tofu doughnut (with tofu paste) and NSP-tofu doughnut (with tofu paste and NSP) were prepared. The moisture and total lipid (TL) content, cross-section image, color characteristic, and specific volume were measured. The tofu and NSP-tofu doughnuts exhibited higher moisture and lower TL content than the control. OTR was 10.8% for the tofu doughnut, and between 13.2% and 41.2% for the NSP-tofu doughnut. The highest OTR (41.2%) was found in the NSP-tofu doughnut with a combination of tofu paste and sodium alginate (NaA). The specific volume of the NSP-tofu doughnuts with combinations of tofu paste with NaA (2.5 mL/g), locust bean gum (2.5 mL/g), and ${\kappa}$-carrageenan (2.4 mL/g) was very close to that of the control (2.6 mL/g). Considering the OTR and specific volume of doughnuts, the combination of tofu paste and NaA would be most effective in reducing the oil uptake of doughnuts during deep-fat frying.

• Journal of Plant Biotechnology
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• v.8 no.1
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• pp.43-50
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• 2006

The goal of this research was to develop an efficient cryopreservation protocol for germplasms of yam (Diosorea batatas), that were cultivated in Korea. Comparative studies with four other cryogenic techniques and subsequent experiments for shoot regrowth were conducted. in vitro-grown shoot-apices of the D. batatas were successfully cryopreserved by encapsulation-dehydration. The maximum survival of shoot-apices could be achieved when the precultured (with 0.3 M of sucrose for one day) and encapsulated (with a 3%(w/v) Na-alginate solution) apices were dehydrated for $3.5{\sim}4\;h$ prior to direct immersion in LN (liquid nitrogen). The frequency of regrowth rate of cryopreserved apices was not decreased during 3-month storage period. The thawing method markedly affected survival of the cryopreserved apices, and thawing at $40^{\circ}C$ for 3 min produced the best results. When cryopreserved apices were post-cultured on the post-culture medium (MS), supplemented with $0.2mgl^{-1}$ of BA ($N_6$-benzyladenine) and $0.2mgl^{-1}$ of kinetin, they showed direct shooting without callusing.

• Fisheries and Aquatic Sciences
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• v.19 no.4
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• pp.15.1-15.5
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• 2016

Apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, nitrogen-free extract, and energy in selected carbohydrate sources including wheat flour (WF), ${\alpha}-potato$ starch (PS), ${\alpha}-corn$ starch (CS), Na alginate (AL), dextrin (DEX), and carboxymethyl cellulose (CMC) were determined for olive flounder. The olive flounder averaging $150{\pm}8.0g$ were held in 300-L tanks at a density of 30 fish per tank. Chromic oxide was used as the inert marker. Feces were collected from the flounder by a fecal collector attached to a fish rearing tank. Apparent dry matter and energy digestibilities of flounder fed WF, PS, CS, and DEX diets were significantly higher than those of fish fed AL and CMC diets. Apparent crude protein digestibility coefficients of flounder fed PS and CS diets were significantly higher than those of fish fed AL, DEX, and CMC diets. Apparent crude lipid and nitrogen-free extract digestibility coefficients of flounder fed PS and DEX diets were significantly higher than those of fish fed WF, CS, AL, and CMC diets. The present findings indicate that PS and DEX could be effectively used as dietary carbohydrate energy compared to WF, CS, AL, and CMC for olive flounder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.1
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• pp.1-6
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• 2004

In preparing sodium alginates from sea tangle (Laminaria japonica) powder using the Mexican process, alkaline extraction, conversion to alginic acid and reversion to sodium alginates were used to increase purity. The effect of hot water treatment and dialysis on measuring the average molecular weight of sodium alginates were investigated. Intrinsic viscosity and average molecular weight of sodium alginates after dialysis were higher than those before dialysis. Average molecular weight of sodium alginates treated with hot water was higher than that without. Hot treatment has little effect on the ash content of sodium alginates. Ash content of sodium alginates before dialysis were $27-30\%$ those after dialysis were $10\%.$ After dialysis, Na content was highest $(89-91\%),$ K was $11-12\%,$ Ca was $1.9\%,$ and Mg was $0.05\%.$ Ash content of alginates had little effect on average molecular weight. SAV (slope of apparent viscosity) of alginates solution after dialysis showed higher values than before. SAV of the alginates with hot water treatment were higher than without treatment.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2002.11b
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• pp.53-53
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• 2002

Shoot tips of in vitro propagated plantlets were cryopreserved using encapsulation/dehydration procedures. Shoot tips were excised under filter sterilized antioxidants solution (0.2M phosphate buffer, pH 5.7 supplemented with 5g/1 ascorbic acid and 15g/1 sodium borate). They were drawn up into a sterile 10 $\textrm{cm}^3$disposable pipette and were dropped into the culture medium with 2.5w/v Na-alginate, then into 100mM CaCl$_2$.2$H_2O$. Encapsulated shoot tips were transferred into 10㎤ of liquid culture medium with a range of sucrose concentrations (0.25-1.0M) and were incubated in dark for 24 hours in 18C at 40rpm. Beads were then dehydrated in silica gel for different time intervals (1-24 hours). Then they were freeze dried either rapidly (plunge directly into liquid N2 or in two stages (samples were kept at 20C for 10 minutes, then reduced to 35C at 1C per minute. Then, plunge into liquid $N_2$). The influence of sucrose and silica gel pre-treatment on pre- and post-freeze shoot growth was examined.(중략)