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PubMed1989

Kinetic behavior and interaction of bacampicillin in alginic acid solution at neural pH region.

Stabilization of bacampicillin (BAPC) in suspension was examined by the addition of alginic acid (Alg). BAPC formed a slightly water-soluble adduct (BAPC-Alg) with Alg, in which BAPC and Alg were presumed to be linked by ionic bonding. However, the suspension of this chemically stable adduct showed a lability to a suspension of BAPC alone; chemically very unstable particles of BAPC base were deposited in the suspension. In contrast, when BAPC-Alg adduct was suspended in 1.0% Alg solution at the same pH region, the precipitation of the particles of BAPC base were not observed. This stabilization is supposed to be due not only to the chemical stability of the adduct, but also to an inhibition of the deposition of an unstable BAPC base particles by Alg.

Alginates↗

PubMed1989

Studies on sustained-release suppositories. I. Effect of alginic acid addition on rectal absorption of bacampicillin in rabbits.

Sustained-release suppositories of bacampicillin (BAPC) were prepared by the use of the adduct which was precipitated from an aqueous solution containing BAPC and alginic acid (Alg). As the suppository base, Witepsol H-15 and macrogol were used. Absorptions of BAPC from the suppositories were prolonged in rabbits, but the bioavailabilities were decreased compared to that after administration of BAPC alone. However, these absorptions were improved enormously by the addition of surface-active agents, that is, an excellent prolonged absorption and high bioavailability were obtained. Interestingly, similar prolonged absorption could be obtained only by mixing Alg with BAPC in a suppository base. Further, this absorption rate was found to be controlled by the amount of Alg addition. The absorption profiles from a suppository containing the mixture differed from that containing the adduct in exhibiting both high plasma level and prolonged absorption. This may be due to simultaneous fast absorption of BAPC itself and formation of the adducts. Thus, it seemed that BAPC preparations containing Alg may be practically useful as a rectal preparation with prolonged action and giving a high plasma level.

Alginates↗

PubMed1990

Studies on sustained-release suppositories. III. Rectal absorption of morphine in rabbits and prolongation of its absorption by alginic acid addition.

Rectal absorption of morphine from various kinds of suppository bases was investigated. The extent of bioavailability of morphine by rectal administration varied with the bases used (30.5-97.5%), but every value was higher than that in the case of oral administration (13.5%). Witepsol bases were preferable to macrogol base for the rectal absorption of morphine. In particular, Witepsol S-55 or W-35 gave a higher plasma peak level than H-15 or E-75, whereas the difference in the mean residence times obtained from these bases could not be regarded as significant. Sustained-release suppositories of morphine could be prepared simply by mixing alginic acid (Alg) with morphine in a suppository base. Further, prolonged rectal absorption could be obtained by using these sustained-release suppositories, and the absorption rate was controlled by the amount of Alg added. It seems likely that the sustained release was due to the binding of morphine to Alg from the results of partition coefficient and binding ratio measurements in aqueous solution. The rapid initial absorption and the subsequent prolonged absorption of morphine simultaneously obtained from the morphine-Alg suppository may be useful in the clinical context.

Alginates↗

PubMed1994

[Sustained-release effect of the direct compressed tablet based on chitosan and Na alginate].

In the dissolution test of tablets prepared by the direct compression of chitosan with 10% sodium alginate (NaAlg), the release of theophylline was extended independently of the medium pH. The drug release mechanism of the tablet was investigated by measuring the dissolution behavior of such excipients as chitosan and NaAlg. It was shown that at the lower pH the drug release was accompanied with the dissolution of chitosan, while at the neutral pH it was controlled by the gelation and dissolution of NaAlg. Further more by the oral administration of the tablet to beagle dogs, the sustained release of theophylline was also confirmed by some bioavailability parameters. Thus the chitosan tablet with 10% NaAlg was expected to be a pH-independent sustained release dosage form.

Administration, Oral↗

PubMed2006

Detection of alginate oligosaccharides from mollusks.

We attempted in this study to detect alginate oligosaccharides (AO) from mollusks. The samples used were digestive organs taken from turban shells and abalones which commonly ate brown algae. High-performance liquid chromatography (HPLC) and negative-ion electrospray ionization (ESI) quadrupole time-of-flight (Q-TOF) mass spectrometry (MS) analyses were used to confirm the presence of AO. Samples spiked with AO resulted in observable peaks where the HPLC area was increased. The highest content was estimated to be 401.8 mg/100 g of digestive organ. The product-ion data derived from AO molecular weight were detected at a constant interval by Q-TOF MS/MS analysis. These findings indicate that AO was present in the digestive organs of mollusks.

Alginates↗

PubMed2006

Oral administration of alginic acid oligosaccharide suppresses IgE production and inhibits the induction of oral tolerance.

We have found that alginic acid oligosaccharide (ALGO) enhanced Th1 by promoting IL-12 production, suggesting that ALGO can be applied as an anti-allergic food. In this study we examined both positive and negative functions of ALGO. First we investigated the anti-allergic activity of ALGO, as a positive function, when orally administered. IgE production was significantly inhibited in mice fed ALGO as compared to control mice. This result indicates that ALGO had anti-allergic activity even when orally administered. On the other hand, we also found a negative function of ALGO. Oral co-administration of a protein antigen and ALGO inhibited the induction of oral tolerance to the protein. These data indicate the potential of ALGO as an anti-allergic food material and the necessity of further examination to determine a safe method application.

Administration, Oral↗

PubMed2007

Induction of multiple cytokine secretion from RAW264.7 cells by alginate oligosaccharides.

We investigated the cytokine-inducing activities of guluronate (G3-G6) and mannuronate (M3-M6) oligomers on RAW264.7 cells with the Bio-Plex assay system. Relatively high levels of tumor necrosis factor-alpha (TNF-alpha), granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein-1 (MCP-1), regulated upon activation normal T cell expressed and secreted (RANTES), granulocyte macrophage (GM)-CSF, and eotaxin were induced by alginate oligomers to different extents depending on the oligomer structures, and low but significant levels of interleukin (IL)-1alpha, IL-1beta, IL-6, IL-9, and IL-13 were also induced. Throughout all cytokines tested, M-oligomers tended to be more potent than G-oligomers in terms of cytokine induction, and this tendency was evident in differences between G3 and M3.

Alginates↗

PubMed2003

Enzymatically depolymerized alginate oligomers that cause cytotoxic cytokine production in human mononuclear cells.

Enzymatically depolymerized guluronate and mannuronate oligomers were prepared from polyuronates with an alginate lyase from a Pseudoalteromonas sp., and their effects on mononuclear cells from human peripheral blood were examined. Conditioned medium prepared by the incubation of cells with an untreated polyuronate had little effect on growth of human leukemic U937 cells, but a medium prepared with depolymerized uronate oligomers inhibited their growth. Inhibition was greater in a medium prepared with guluronate oligomer than one prepared with mannuronate oligomer. The cytotoxic activity of the medium was heat-labile and nondialyzable. Apoptotic nuclear morphological changes and increased caspase-3-like activity were found in U937 cells treated with a medium prepared with depolymerized uronates. The medium prepared with purified tetra-guluronate and tetra-mannuronate also was cytotoxic; these effects were inhibited by antibodies to tumor necrosis factor-alpha. Our results suggested that enzymatically depolymerized guluronate and mannuronate oligomers induced the production of cytotoxic cytokines in human mononuclear cells, although the uronate polymers before depolymerization had no such activity.

Alginates↗

PubMed1994

[An experimental study on a chemosensitivity test with alginate microcapsule. Feasibility of in vivo succinic dehydrogenase inhibition test].

A new chemosensitivity test was evaluated by the MTT colorimetric asay with human tumor cell lines encapsulated in alginate microcapsules with semipermeable membranes. The proliferation of KATOIII in the microcapsules rapidly increased on the 4th day after the encapsulation. The change expressed on the proliferation curve of the encapsulated KATOIII was approximately 2 days behind the proliferation of the suspension culture. The encapsulated cell number reversed and further proliferation was recognized after the 12th day. After the incubation for 5 hours of encapsulated KATOIII with the medium supplemented with 0.5% MTT, a blue formazan crystal formation was observed radiating around the cells in the capsules. MTT assay depends on the cellular reduction of the absorbance spectra at 540 nm (OD540nm), for complete solubilization of the formazan by DMSO. The formazan formation was observed more significantly in serum medium culture than in serum free medium. In MIT assay when 0.1 mol succinic acid was added, OD540nm of encapsulated KATOIII increased by approximately 50% and its sensitivity also increased greatly. In comparison the results of MTT assay for encapsulated KATOIII and MKN28 with suspended cells under the same conditions (0.1, 1, 10 micrograms/ml of MMC and ADR, 0.5, 5, 50 micrograms/ml of 5FU, 10, 30, 50 micrograms/ml of CDDP), the calculated inhibition index (%) with encapsulated cells were similar to the percentages obtained in the former MTT assay. In this study with microcapsules, the formazan formation in the capsules and the absorbance were macroscopically inhibited when the drug concentration was increased. The encapsulated KATOIII, which was implanted intraperitoneally into rat with a 16-gauge needle, was recovered at a rate of 70.8% on the 8th day and at a rate of 54.5% on the 16th day. The recovered encapsulated KATOIII proliferated remarkably forming cell clots on the 8th day after implantation. Incubation with MTT promoted formazan formation and sufficient cell viability was recognized. The Tegafur concentration in the intraperitoneal microcapsules and the microcapsules containing KATOIII after the intravenous administration of Tegafur was similar to the intrahepatic level. The 5FU level in the microcapsules containing KATOIII was higher than that in the capsules alone. In an attempt to conduct an in vivo chemosensitivity test, encapsulated KATOIII and MKN28 were intraperitoneally implanted, 4 mg/kg of MMC, ADR and CDDP, and 75mg/kg of 5FU were intravenously administered on the 2nd and 4th days after the implantation. On the 6th day, MTT assay was performed on the recovered microcapsules containing cells and the inhibition index was calculated.(ABSTRACT TRUNCATED AT 400 WORDS)

Alginates↗

PubMed1994

[Stromal changes in cancer. Studies on changes of stroma promoted by gastric cancerous cells using alginate microcapsules].

Xenografting can be accomplished by using encapsulated cells in the alginate microcapsule. Using this technique, the experiment was made to investigate the stroma-promoting factors that were produced by the encapsulated differentiated (MKN-28) and undifferentiated (KATO-III) gastric cancerous cell lines. Fibronectin (FN) in the medium was quantified by single culture with the human fibroblast cell line (CCD-32Lu) and coculture with CCD-32Lu and the encapsulated MKN-28 ro KATO-III. Then following this procedure, each capsule including the gastric cancerous cells was subcutaneously transplanted into Wistar Rats. After 14 days, the surrounding tissues of the microcapsules were stained, and the localization of type III collagen, 4 and 6 chondroitin sulfate, and FN were observed by immunohistochemical stainings. The concentration of FN in both single culture and coculture medium gradually increased, especially in the medium complemented with KATO-III and CCD-32Lu. The measured point after 48 hours demonstrated the obvious increase compared to the single culture and coculture medium. Upon the histological comparison, it was found that the stromal proliferation around the tissue transplanted the microcapsules including MKN-28 or KATO-III were distributed more abundantly than the transplantation of microcapsules only. However, no difference was noted between the stroma of MNK-28 and KATO-III. In conclusion, this study suggests that any stroma-promoting factor is produced by the gastric cancerous cells.

Adenocarcinoma↗

PubMed2002

Proliferation of canine intervertebral disk chondrocytes in three-dimensional alginate microsphere culture.

Proliferation of chondrocytes from nucleus pulposus (NP) and anulus fibrosus (AF) was confirmed in three-dimensional culture using alginate microspheres. Cells isolated from NP and AF were incorporated in microspheres and cultured for 14 days. Round mononuclear cells of 20-25 microm in diameter proliferated and formed aggregates. At day 14, alcian blue positive matrix surrounded the proliferating cells. The cells had cytoplasmic vacuoles stained positively by toluidine blue. On electron microscopy, the cells contained proteoglycan vacuoles and lipid droplets in the cytoplasm and synthesized collagen fibrils and electron dense granules surrounding the cell. These features of the cells were characteristic for chondrocytes. This culture system should be useful to further investigate metabolic activities of intervertebral disk chondrocytes.

Alcian Blue↗

PubMed2001

Comparison of hydrocellular foam and calcium alginate in the healing and comfort of split-thickness skin-graft donor sites.

This is a comparative study of a hydrocellular foam (Allevyn, Smith and Nephew) and a calcium alginate (Kaltostat, ConvaTec) in dressing split-thickness skin-graft donor sites. The dressing materials were used in equal halves of each donor site in 20 patients undergoing skin-graft harvest. The donor sites dressed with Allevyn showed a tendency to earlier healing, but this was not confirmed statistically. However, Allevyn was found to be more comfortable than Kaltostat and this difference was statistically significant. Due to its increased patient comfort, cheaper cost and comparable time to healing with Kaltostat, the authors recommend the use of Allevyn as a dressing for split-thickness skin-graft donor sites.

Adolescent↗

PubMed2003

Calcium alginate gel as encapsulation matrix for coimmobilized enzyme systems.

Encapsulation within calcium alginate gel capsules was used to produce a coimmobilized enzyme system. Glucose oxidase (GOD) and catalase (CAT) were chosen as model enzymes. The same values of Vmax and Km app for the GOD encapsulated system and for the GOD-CAT coencapsulated system were calculated. When gel beads and capsules were compared, the same catalyst deactivation sequence for the two enzymes was observed. However, when capsules were employed as immobilization support, GOD efficiencies were higher than for the gel beads. These results were explained in terms of the structure of the capsules.

Alginates↗

PubMed1999

Characterization of invertase entrapped into calcium alginate beads.

A solution of 10 g/L of sodium alginate (Satialgine types used [Sanofi trademark]: SG800 and S1100 with manuronic/guluronic ratio of 0.5 and 1.2, respectively) containing invertase (0.08 g of protein/L) was dropped into 0.1 M CaCl2 solution buffered at pH 4.0, 7.0, or 8.0. The beads were left to harden in CaCl2 solution for 24 h. The high immobilization yield of 60% occurred with SG800 at pH 8.0. The activity of soluble and insoluble invertase was measured against pH (2.8-8.0), sucrose concentration (4.5-45 mM), and temperature (30-60 degrees C). Both forms presented an optimum pH of 4.6. However, the soluble invertase was stable at the overall pH interval studied, whereas insoluble invertase lost 30% of its original activity at pH > 5.0. At temperatures above 40 degrees C, the insoluble form was more stable than the soluble one. The kinetic constants and activation energies (Ea) for free invertase were KM = 41.2 mM, Vmax = 0.10 mg of TRS/(min.mL), and Ea 28 kJ/mol for entrapped invertase they were (KM)ap = 7.2 mM, (Vmax)ap = 0.060 mg of TRS/(min.mL), and (Ea)ap = 24 kJ/mol.

Alginates↗

PubMed2001

Purification of alpha-amylases using magnetic alginate beads.

Magnetic alginate beads were used to purify alpha-amylases from porcine pancreas, starchzyme, BAN 240L (a commercial purification from Bacillus subtilis), and wheat germ. The beads bound a significant level of alpha-amylase activity from porcine pancreas, BAN 240L, and wheat germ. In each case, the enzyme activity could be eluted by using 1.0 M maltose, a known competitive inhibitor of alpha-amylase. In the case of BAN 240L, 3.6-fold purification with 72% recovery of activity was observed. In the case of wheat germ enzyme, starting from the crude extract, 48-fold purification with 70% activity recovery was observed. Sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis also indicated considerable purification in the latter case.

Alginates↗

PubMed2001

Modeling of saccharide utilization in primary beer fermentation with yeasts immobilized in calcium alginate.

Immobilized beer fermentation was studied using an industrial bottom-fermenting yeast strain Saccharomyces cerevisiae. The yeast cells were immobilized in 2.5% calcium alginate gel and used for brewing in a five-vessel cascade reactor. The fermentation was performed at 15 degrees C at various flow rates. A nonstructured mathematical model was developed to simulate the performance of continuous primary fermentation of lager beer. The model was based on the following variables: maltose, maltotriose, glucose, fructose, ethanol, and cell concentration. Experimental values of these variables were determined in samples taken at regular intervals. For experimental data fitting a nonlinear regression was used. Substrate consumption was characterized by specific substrate consumption rate and saturation constant. The values of these two parameters were optimized for all four substrates. Inhibition effects of substrates and product were analyzed using various inhibition patterns. Only the inhibition effect of maltose on maltose consumption was clearly identified. A good-fitting relationship for maltose inhibition was found, and inhibition constants were calculated.

Alginates↗

PubMed2002

Magnetite-alginate beads for purification of some starch degrading enzymes.

Starch degrading enzymes, viz., beta-amylase, glucoamylase, and pullulanase, were purified using magnetite-alginate beads. In each case, the enzyme activity was eluted by using 1.0 M maltose. beta-Amylase (sweet potato), glucoamylase (Aspergillus niger), and pullulanase (Bacillus acidopullulyticus) from their crude preparations were purified 37-, 31-, and 49-fold with 86, 87, and 95% activity recovery, respectively. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis showed single band in each case.

Alginates↗

PubMedDate not supplied

Biodegradation of naphthalene by free and alginate entrapped Pseudomonas sp.

Naphthalene degradation by freely suspended and immobilized cells of Pseudomonas sp. isolated from contaminated effluents has been investigated in batch cultures and continuously in a packed bed reactor. Naphthalene concentration was varied from 25 mM to 75 mM, the temperature (30 degrees C) and pH (7.0) were kept constant. The results showed good acclimation of the strain to carbon source and degradation rate was highly affected by initial concentration. Alginate-entrapped cells have given good yields although initial rates were not as high as those encountered with free cells. A first order exponential decay kinetic model was proposed with values of parameters for each initial concentration. A laboratory scale packed-bed bioreactor was designed using parameters calculated above and continuous experiments were realized at different flow rates (100 to 200 ml/h), with different feed concentrations and operating during 30 days. The conversion at low feed concentrations and low flow rates was complete whereas at high flow rates and high concentrations it was less efficient because of diffusional limitations and short residence time.

Alginates↗