• Journal of Life Science
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• 제9권1호
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• pp.45-49
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• 1999

Seaweed alginate was acetylated by activated carbon immobilized Pseudomonas syringae in a fluidized bed, up-flow reactor. The acetylation degree of seaweed alginate was about 30%. Calcium-acetylated seaweed alginate gel bead was made and compared to calcium-seaweed alginate gel bead by the scanning electron microscopy (SEM). Structural difference of two gel beads may results from increased viscosity and decreased affinity of acetylated seaweed alginate for calcium ion. On the basis of interior and exterior structure of calcium-acetylated seaweed alginate gels and property of acetylated seaweed alginate, it seems that acetylated seaweed alginate is used for the supporter for electrophoresis and packing materials for liquid chromatography and gel filtration.

• 한국축산식품학회지
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• 제30권5호
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• pp.746-754
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• 2010

Response surface methodology was adopted to model and optimize the effects of microbial transglutaminase (TG) and calcium alginate (CA) systems of various ratios on the gelation characteristics of porcine myofibrillar protein (MP) at various salt levels. The CA system consisting of sodium alginate (SA), calcium carbonate (CC) and glucono-$\delta$-lactone (GdL) showed no remarkable changes in the salt-soluble fraction, and only minor effects on electrostatic interactions were observed. Increasing CA concentration caused acid-induced hydrophobic interactions in MPs, resulting in increased MP gel strength. The TG system, containing TG and sodium caseinate (SC), induced cold-set MP gelation by formation of covalent bonding. The main advantage of the combined system was a higher cooking yield when the MP gel was heated. These results indicated that 0.7% TG combined with 0.8% CA system can form a viscoelastic MP gel, regardless of salt levels.

• Food Science and Biotechnology
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• 제16권5호
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• pp.715-721
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• 2007

In this study, the sphericity of calcium alginate gel beads was optimized using response surface methodology. The optimum conditions for bead sphericity were a concentration of 2.24% sodium alginate, a flow rate of 0.059 mL/sec for the sodium alginate solution, and a 459 rpm rotation for the calcium chloride solution. The predicted and experimental bead sphericities under the optimum conditions were 94.5 and 96.7%, respectively, showing close agreement. We also investigated the processing condition effects for the physical properties of the optimized calcium alginate gel beads. Immersion in hot water slightly decreased bead size and rupture strength. NaCl treatment increased bead size and decreased rupture strength. While the pH of the calcium chloride solution had little effect on bead sphericity, the bead sizes and gel strengths decreased with longer times in each pH solution. The beads coated with pectin and glucomannan showed no significant changes in sphericity, but their sizes decreased with time. The coated beads showed higher rupture strengths than the uncoated beads.

• 한국축산식품학회지
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• 제29권5호
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• pp.590-598
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• 2009

The aim of this study was to model and optimize the calcium alginate (CA) and microbial transglutaminase (TG) systems to form a cold-set myofibrillar protein (MP) gel containing 0.1 M or 0.3 M NaCl using a response surface methodology. The gel strengths of cold-set and heat-induced MP gels, and cooking yields were measured. All measured parameters showed determination coefficients ($R^2$) above 0.7 without a lack-of-fit. The CA system had the best results with component ratios of 1.0:0.3:1.0 corresponding to sodium alginate, calcium carbonate and glucono-$\delta$-lactone, respectively, and was favourable at 0.1 M NaCl. In contrast, the TG system only had an effect on cold-set MP gelation at 0.3 M salt, and the optimal ratio of TG to sodium caseinate was 0.6:0.5. By combining the two systems at 0.3 M NaCl, an acceptable cold-set MP gel with an improved texture and high cooking yield could be formed. Therefore, these results indicated that the functionality of the cold-set MP gel could be enhanced by combining these two optimized gelling system.

• 한국미생물·생명공학회지
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• 제9권3호
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• pp.159-164
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• 1981

부분적 항상성변이주인 Bacillus megaterium (KFCC 10029)가 생산하는 페니실린 아미다제를 예로하여 강화된 $Ca^{++}$-alginate gel에 의한 포괄방법을 이용하는 효소 고정화 방법을 제시하였다. 발효액으로 부터 celite 흡착법에 의해 효소를 분리한 후 alginate의 gellatin용액에 혼합하고 $Ca^{++}$ 용액에서 응고시키고 glutaraldehyde로 처리하여 성형하였다. 이렇게 하여 얻은 고정화효소의 최적 pH 및 온도는 각각 8.0과 6$0^{\circ}C$였다. Km value 와 6-APA 및 페닐초산에 의한 저해 상수는 각각 2.6mM, 7.4mM, 21.2mM이었다. Gel의 증가된 물리적 강도 때문에 반응조 조작중 흡착효소의 유실을 성공적으로 없앨수 있었다. 관형식 반응조에서의 고정화 효소의 반감기는 4$0^{\circ}C$와 3$0^{\circ}C$에서 각각 6일 및 30일이었으며, 이것은 흡착효소와 비교해 볼 때 6-8배의 증가치이다. 결론적으로 alginate gel 포괄방법에 의한 효소고정화 방법에 있어, 본 연구에서 개발된 개량된 방법을 사용함으로써 고정화효소의 물리적 강도 및 안정도를 크게 증가시킬 수 있었다.

• 한국수산과학회지
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• 제49권1호
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• pp.20-25
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• 2016

This study elucidated the effects of physicochemical factors on the production of cooked rice analogs using calcium alginate gels. Cooked rice analogs were prepared using various sodium alginate concentrations, agitation speeds, dropping distances, coating times, curing times and heating times. The diameter ratio and rupture strength of authentic cooked rice were 0.38 and 268.4 kPa, respectively. The diameter ratio of the analogs prepared with 0.7% (w/v) sodium alginate was 0.39, which was the closest to that of authentic cooked rice. When sodium alginate solution (0.7%, w/v) was dropped into calcium chloride solution (2%, w/v) via a nozzle, the diameter ratio of the analogs at an agitation speed of 520 rpm was 0.39. The optimal dropping distance was 8 cm and the optimal coating and curing times were each 20 min. The analogs were coated with β-cyclodextrin to improve their physical properties. The diameter ratio of the coated analogs was little changed; however, the rupture strength decreased slightly after heating for 60 min at 95°C.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권4호
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• pp.206-211
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• 2002

Calli obtained from a shoot-tip of garlic, Allium sntivum L., were encapsulated using a calcium alginate gel. Some of the encapsulated calli were cultured on a 1/2 MS medium supplemented with 3% sucrose, 10$\^$-5/ kinetin, and 5 ${\times}$ 10$\^$-6/ M NAA whereas the remainder was stored for 40 days at 4$^{\circ}C$. All the naked calli regenerated on the solid medium, while 95% of the encapsulated calli regenerated, and 88% of the encapsulated calli regenerated after 40 days of storage at 4$^{\circ}C$. The capsule matrix delayed the germination time of the encapsulated calli, yet activated the shoot formation of the artificial garlic seeds. The shoot length of the encapsulated garlic calli was much longer than that of the naked garlic calli. The encapsulated garlic calli were dried in a laminar airflow cabinet and the conversion frequency of the dried artificial garlic seeds on a 1/2 MS medium remained at 93% with a water Loss of Less than 50%.

• 한국미생물·생명공학회지
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• 제20권4호
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• pp.459-469
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• 1992

세균을 고정화시켜 에탄올을 생산하기 위하여 4종류의 Zymomonas mobilis를 사용하였다. 이들 중 glucose와 sucrose로부터의 에탄올생성능이 가장 우수한 것으로 Zymomonas mobilis KCTC 1534를 선별하였다. 선별된 균주의 고정화 특성을 살펴본 결과 발효 최적온도와 pH는 각각 $33^{\circ}C$와 5.0으로 고정화 균체나 유리 균체에 대하여 큰 차이가 없었다. 그러나 최대 발효 가능온도는 유리 균체가 $37^{\circ}C$인데 비하여 alginate, k-carageenan, agar에 고정화했을 때 각각 43, 37, $40^{\circ}C$로서 균체를 고정화할 경우 유리균체에서 보다 높은 온도에서도 발효가 가능함을 확인하였다. Alginate 고정화 균체는 2% alginate 농도에 건조균체량 11.74g/$\ell$가 최적이었따. 고정화 균체의 활성화는 10% glucose 농도의 생산배지에서 20~25시간을 요 하였고 $4^{\circ}C$에 보관할 경우 calcium chloride 2%를 가한 증균배지에서 약 4주간은 전균체량의 90% 이상이, 10주간에는 80% 이상의 균체가 생존하였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.40.2-40.2
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• 2010

In this study, oxidized alginate/gelatin/biphase calcium phosphate (BCP)- based hydrogel composites were fabricated. Alginate sodium was oxidized by periodate. The oxidized product was confirmed by using $^1H$ and $^{13}C$ NMR spectra. The number average molecular weight ($M_n$), the average molecular weight ($M_w$) of the oxidized alginate were determined by Gel Permeation Chromatography (GPC). The hydrogel was formed from the oxidized alginate and gelatin solution via Schift-base reaction. The hydrogel showed a highly porosity by a Scanning Electron Microscope (SEM) and Mercury Intrusion Porosimetry (MIP). Crosslinked density of the gel matrix were assessd by trinitrobenzene sulfonic acid (TNBS) assay that shows a high effect on swelling ratio. Increment of the crosslinked desity resulted in enhancing compressive strength of the hydrogel composite. The cytotoxity of hydrogel was assessed with osteoblast MG-63. The hydrogel composites show a high compatibility. The obtained results showed a potential application for bone regeneration in future.

• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.229-233
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• 1995

Acremonium chrysogenum was immobilized in ionotropic gel beads to develop semi-continuous production of cephalosporin C (CPC). Barium alginate beads were more stable than calcium alginate or strontium alginate beads in chemically defined media. The gel stability of Ba-alginate was further increased by cross-linking with polyethyleneimine (PEI). The presence of carboxymethyl cellulose inside Ba-alginate beads did not reduce mass transfer resistance. Ba-alginate microbeads that had little diffusion limitation increased CPC production rate 1.6 fold higher than that of normal beads. CPC fermentation with immobilized cells in Ba-alginate microbeads was performed continuously for 40 days by way of repeated fed-batch operations. Mathematical modeling was developed to describe the repeated fed-batch fermentation system. Results of the computer simulation agreed well with the experimental data, which made it possible to predict an optimal feeding rate that could maximize total CPC productions.