• Journal of Pharmaceutical Investigation
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• 제33권2호
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• pp.121-127
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• 2003

The objective of this study was to solidify the simvastatin self-microemulsifying drug delivery system (SMEDDS) and to improve the encapsulation efficiency of solidified alginate beads using sodium alginate. Typical simvastatin SMEDDS was composed of various oils, surfactants and cosurfactants. Also solidified-alginate beads was prepared by crosslinking liquid emulsion mixtures containing sodium alginate and other excipients (cetylpyridinum chloride (CP-Cl), hydroxypropyl methylcellulose, starch and so on). in $CaCl_2$ solution, it has been investigated that the drug release pattern and encapsulation efficiency were varied with the ratio of cationic lipid (CP-Cl). Solidified sodium alginate beads containing simvastatin SMEDDS were redispersed into media without re-aggregation. Oil droplet size of redispersed solidified-beads in media produced smaller than the initial size. The density of beads and drug loading amount were increased with increasing cationic lipid content. These systems have advantages of storage stability and predictability of drug release rate.

• Journal of Pharmaceutical Investigation
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• 제41권1호
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• pp.51-57
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• 2011

The objective of this study was to enhance the utilitization of Ibuprofen (IBU) by introducing the fast-disintegrating tablet (FDT) form. Presently, IBU is being widely used as a tablet or syrup form. But in contrast to these two formulations, IBU as FDT is not only convenient but also increases the control over the time release of the drug, noted by using Alginate beads. This study was carried out with Sodium Alginate and IBU at the ratios of 1:0, 1:0.5, 1:1, and 1:2 in order to produce a series of beads with different ratios. During the drying process of the beads, talc was added in beads to compare the effects with and without the talc. The final product was scanned with SEM imaging to determine the difference in the surface of the beads. The parameters assessed were the diameter, content assay, dissolution test and effectiveness of time-release. Direct compression method was used to prepare FDT containing IBU bead. The properties of FDT, such as hardness, disintegration time, were investigated. The dissolution profiles of FDT were tested using KP dissolution apparatus 1 (basket method). The results suggest addition of talc and drying the beads made the surface smooth and less vulnerable to clutter into chunks. The size of beads was less than 300 ${\mu}m$ which did not create a sandy feeling in the mouth. Thus, the beads formulation model made the sustained release of the drug possible, the hardness of FDT (1.25~1.50 $Kg/cm^2$) was acceptable and all the values of dissolving period were less than 30 seconds. The dissolution profile of FDT was same as that of IBU bead. The efficient dissolution profile and low price of IBU bead containing Sodium Alginate, the FDT formulation prepared from IBU bead can save the expenses and can improve the convenience of application of this drug.

• Bulletin of the Korean Chemical Society
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• 제34권9호
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• pp.2741-2746
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• 2013

The immobilization of enzyme is one of the key issues both in the field of enzymatic research and industrialization. In this work, we reported a facile method to immobilize Candida Antarctica lipase B (CALB) in alginate carrier. In the presence of calcium cation, the enzyme-alginate suspension could be cross-linked to form beads with porous structure at room temperature, and the enzyme CALB was dispersed in the beads. Activity of the enzyme-alginate composite was verified by enzymatic hydrolysis reaction of p-nitrophenol butyrate in aqueous phase. The effects of reaction parameters such as temperature, pH, embedding and lyophilized time on the reactive behavior were discussed. Reuse cycle experiments for the hydrolysis of p-nitrophenol butyrate demonstrated that activity of the enzyme-alginate composite was maintained without marked deactivation up to 6 repeated cycles.

• Journal of Pharmaceutical Investigation
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• 제28권2호
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• pp.109-113
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• 1998

This study is purposed to develop the sustained release and bioavailability of piracetam (PA). The use of alginate beads as a means to achieve sustained release of piracetam was evaluated in comparison with that of piracetam alone. In the PA-sodium alginate(SA) beads was confirmed by differential scanning calorimetry thermogram(DSC), indicating a relative shift of an endometric peak of PA to higher temperature. The changes in dissolution rates from PA-SA beads and PASA beads coated by chitosan(CHO) were significantly slower than that of intact PA. The release rate of PA-SA in the gastric fluid was markedly decreased compared with that in the intestinal fluid, suggesting that PA is mostly released in the intestinal fluid. However, the PA/SA ratio scarcely affected the release profile. The blood concentration- time curves of PA, PA-SA and PA-SA-CHO were obtained by oral administration to rats. $T_{max}$ of PA, PA-SA and PA-SA-CHO were 1, 10 and 6 hours, respectively. It was confirmed that the release of PA was prolonged by the formulation of PA-SA beads and PA-SA-CHO beads.

• KSBB Journal
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• 제14권4호
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• pp.389-395
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• 1999

Bifidobcterium spp. can provide human being with several beneficial physiological. Therefor, there has been a considerable interest in products Bifidobcterium spp. dietary supplements or as starter cultures for probiotic products that may assint in the improvement of health on the human. But indusrial applications have been limited because Bifidobcterium spp. are sensitive to acidic pH due to organic acid produced by themselves and various conditions. The objective of this study was to establish new method for improvement of Bifidobcterium viability by entrapment im calcium alginate beads. We have a plan to select the most suitable polymer through the comparison with acid tolerance oxygen tolerance and theological properties of polymer. Increase of the viable number of Bifidobcterium induced increasing acid tolerance and oxygen tolernce trough the development of entrapment technique. The 4%, 3030mm diameter) sodium alginate beads led to the best survivability under acid condition. Especially, addition of 6% mannitol, 6% glycerol or 6% sorbitol to the sodium alginate helped a beneficial effect on viability against acid, bile salt, hydrogen peroxide and cold strage. The number of viability of entrapeede cells by retreatment was 96 fold higher than non-entrapeed cells after 5 hours of storage under pH 3 acidic condition. These experimental data clearly demonstrate that a whole cell immobilization by entrapment in calcium alginate beads is an important survival mechanism enable to withstand environmental stresses as the acidic condition, hydrogen peroxide toxicity and frozen state.

• Journal of Microbiology and Biotechnology
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• 제19권6호
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• pp.582-587
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• 2009

Immobilized cells of Arthrohacter nitroguajacolicus ZJUTB06-99 capable of producing nitrilase were used for biotransformation of acrylonitrile to acrylic acid. Six different entrapment matrixes were chosen to search for a suitable support in terms of nitrilase activity. Ca-alginate proved to be more advantageous over other counterparts in improvement of the biocatalyst activity and bead mechanical strength. The effects of sodium alginate concentration, $CaCl_2$ concentration, bead diameter, and ratio by weight of cells to alginate, on biosynthesis of acrylic acid by immobilized cells were investigated. Maximum activity was obtained under the conditions of 1.5% sodium alginate concentration, 3.0% $CaCl_2$ concentration, and 2-mm bead size. The beads coated with 0.10% polyethylenimine (PEI) and 0.75% glutaraldehyde (GA) could tolerate more phosphate and decrease leakage amounts of cells from the gel. The beads treated with PEI/GA could be reused up to 20 batches without obvious decrease in activities, which increased about 100% compared with the untreated beads with a longevity of 11 batches.

• Asian-Australasian Journal of Animal Sciences
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• 제32권1호
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• pp.72-81
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• 2019

Objective: To determine the effect of gut pH and rumen microbial fermentation on glycerol encapsulated in alginate and alginate-chitosan polymers. Methods: Glycerol was encapsulated at 2.5%, 5%, 7.5%, or 10% (w/w) with sodium alginate (A) and alginate-chitosan (AC) polymers. Surface morphology and chemical modifications of the beads were evaluated using scanning electron microscopy and Fourier transform infrared (FTIR) spectra. Encapsulation efficiency was determined at the 5% glycerol inclusion level in two experiments. In experiment 1, 0.5 g of alginate-glycerol (AG) and alginate-chitosan glycerol (ACG) beads were incubated for 2 h at $39^{\circ}C$ in pH 2 buffer followed by 24 h in pH 8 buffer to simulate gastric and intestinal conditions, respectively. In experiment 2, 0.5 g of AG and ACG beads were incubated in pH 6 buffer at $39^{\circ}C$ for 8 h to simulate rumen conditions. All incubations were replicated four times. Free glycerol content was determined using a spectrophotometer and used to assess loading capacity and encapsulation efficiency. An in vitro experiment with mixed cultures of rumen microbes was conducted to determine effect of encapsulation on microbial fermentation. Data were analyzed according to a complete block design using the MIXED procedure of SAS (SAS Institute, Cary, NC, USA). Results: For AG and ACG, loading capacity and efficiency were 64.7%, 74.7%, 70.3%, and 78.1%, respectively. Based on the FTIR spectra and scanning electron microscopy, ACG treatment demonstrated more intense and stronger ionic bonds. At pH 6, 36.1% and 29.7% of glycerol was released from AG and ACG, respectively. At pH 2 minimal glycerol was released but pH 8 resulted in 95.7% and 93.9% of glycerol released from AG and ACG, respectively. In vitro microbial data show reduced (p<0.05) fermentation of encapsulated glycerol after 24 h of incubation. Conclusion: The AC polymer provided greater protection in acidic pH with a gradual release of intact glycerol when exposed to an alkaline pH.

• Journal of the Korean Wood Science and Technology
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• 제51권5호
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• pp.321-333
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• 2023

In this study, lignin, a lignocellulosic biomass, was chemically modified to produce polyethyleneimine-grafted lignin (PKL) with maximum hexavalent chromium [Cr(VI)] adsorption capacity. Changes in the physicochemical properties due to the cationization of lignin were confirmed through elemental analysis, Fourier transform infrared spectroscopy, and moisture stability evaluation. Alginate (Alg) beads containing PKL (Alg/PKL) were prepared by incorporating cationic lignin into the Alg matrix to apply the prepared PKL in a batch-type water treatment process. The optimal Alg/lignin mixing ratio was selected to increase the Cr(VI) adsorption capacity and minimize lignin elution from the aqueous system. The selected Alg/PKL beads exhibited an excellent Cr(VI) removal capacity of 478.98 mg/g. Isothermal adsorption and thermodynamic analysis revealed that the Cr(VI) removal behavior of the Alg/PKL beads was similar to that of heterogeneous chemical adsorption. In addition, the bulk adsorbent material in the form of beads exhibited adsorption behavior in three stages: surface adsorption, diffusion, and equilibrium.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.444-448
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• 2002

A $CaCO_3$-alginate beads system was developed for high cell density cultivation of Bifidobacterium longum and the cost-effective media were also screened. In batch process with $CaCO_3$, beads, two strains of B. longum showed both the highest viable cells and optical density in TPY medium, resulting in maximum optical density and viable cell counts of 12.40, $2.22{\times}10^10$ cfu/ml for B. longum ATCC 15707 and 13.71, $3.93{\times}10^10$ cfu/ml for B. longum HLC 3742. Released size distribution, according to $CaCO_3$-alginate bead size preparation, was smaller than others. These results were also examined by observing their morphology. The skim milk-based medium was most adequate to cultivate B. longum as the cheapest medium, and $10\%$ skim milk supplemented with $2\%$ glucose and $1\%$ yeast extract was a suitable medium, supporting the growth to $5.57{\times}10^10$ cfu/ml for ATCC 15707 and $6.82{\times}10^9$ cfu/ml for HLC 3742. During the long-term storage at $4^{\circ}C\;and\;-20{\circ}C$, B. longum cultivated with $CaCO_3$ beads had the highest stability. Consequently, $CaCO_3$-alginate beads buffer was found to be useful not only to cultivate B. longum but also to preserve cultures.

• KSBB Journal
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• 제18권2호
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• pp.161-164
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• 2003

경구 투여가 비교적 어려운 단백질 약물을 생체적합성이 우수하고 생분해성을 가진 펙틴을 이용하여 목적하는 colon에 전달하고자 하였다. 이온결합을 통해 펙틴, 펙틴-알긴산비드를 제조할 수 있었고, 단백질 약물인 BSA를 포함하여 방출을 행한 결과, 비드의 건조온도가 높을수록 방출률이 높은 경향을 보인 반면, 동결건조된 비드가 가장 높은 방출을 나타냈다. 또한, 가교제의 농도를 높게 처리한 비드일수록 방출률이 낮았다. 경구 투여 후 colon에 도달할 것으로 예상되는 5시간 후에 펙틴 분해효소를 처리한 결과, 효소 처리하지 않은 비드에 비해 급격한 방출이 일어났다. 이러한 결과로 colon내에 존재하는 미생물이 분비하는 효소에 의해 펙턴 비드에 포함된 약물이 방출될 것으로 판단된다. 따라서, 경구로 투여된 펙틴 비드 안의 약물이 소화기관에서 안정하게 통과하고 colon에서 방출되어 효과를 나타낼 것으로 판단된다.