The cis-epoxysuccinate hydrolase (CESH) from Rhizobium strain BK-20 is the key enzyme for L(+)-tartaric acid production. To establish a highly efficient and stable production process, we first optimized the enzyme production from Rhizobium strain BK-20, and then developed an immobilized cell-culture process for sustained production of L(+)-tartaric acid. The enzyme activity of free cells reached (3 498.0 +/- 142.6) U/g, and increased by 643% after optimization. The enzyme activity of immobilized cells reached (2 817.2 +/- 226.7) U/g, under the optimal condition with sodium alginate as carrier, cell concentration at 10% (W/V) and gel concentration at 1.5% (W/V). The immobilized cells preserved high enzyme activity and normal structure after 10 repeated batches. The conversion rate of the substrate was more than 98%, indicating its excellent production stability.
Alginates ; chemistry ; Cells, Immobilized ; Glucuronic Acid ; chemistry ; Hexuronic Acids ; chemistry ; Hydrolases ; metabolism ; Rhizobium ; enzymology ; metabolism ; Tartrates ; metabolism

In this study, we found that when Pseudomonas mendocina NK-01 accumulated intracellular carbon reserve, medium chain length poly (3-hydroxyalkanoates), it also synthesized extracellular saccharides, alginate oligosaccharides. The high carbon nitrogen ratio of culture medium facilitated alginate oligosaccharides production. We analyzed the structure of alginate oligosaccharide by Ultraviolet-Visible Spectrophotometry, Fourier Transform Infrared Spectroscopy, 1H and 13C of Nuclear Magnetic Resonance, and found that it was compounded in line from beta-D-mannuronic acids and alpha-L-gluronic acids via beta-(1-->4)/ alpha-(1-->4) bonds, which acetylated partly on the 2- and/or 3-hydroxy. In addition, we determined the weight-average molecular weight of alginate oligosaccharides by gel permeation chromatography to be 2054.
Alginates ; chemistry ; Glucuronic Acid ; biosynthesis ; chemistry ; genetics ; Hexuronic Acids ; chemistry ; Molecular Weight ; Oligosaccharides ; biosynthesis ; chemistry ; genetics ; Pseudomonas mendocina ; metabolism

With sodium alginate as a carrier and glutaraldehyde as the crosslinking agent, an improved immobilization method of beta-glucosidase for production of soybean genistein was developed. As compared with entrapment or entrapment-crosslinkage, crosslinkage-entrapment that beta-glucosidase was treated with glutaraldehyde and then entrapped in sodium alginate remained high loading efficiency and activity recovery, Effects of bead sizes, concentrations of alginate and glutaraldehyde as well, on the loading efficiency and activity recovery were assessed. When compared with the free enzyme, the optimum temperature, pH value and Km of the immobilized beta-glucosidase were respectively shifted from 50 degrees C to 40 degrees C, 4.5 to 4.0 and 2.57 microg/mL to 2.02 miocrog/mL. The stabilities of the immobilized beta-glucosidase were considerably better than that of the native enzyme. The immobilized beta-glucosidase was employed to genistein production, 84.94% of the activity and 56.04% of conversion were kept after consecutive use of 6 times.
Alginates ; chemistry ; Aspergillus niger ; enzymology ; genetics ; Enzyme Stability ; Enzymes, Immobilized ; metabolism ; Genistein ; chemical synthesis ; chemistry ; Glucuronic Acid ; chemistry ; Glutaral ; chemistry ; Hexuronic Acids ; chemistry ; Isoflavones ; chemistry ; Soybeans ; chemistry ; beta-Glucosidase ; chemistry ; metabolism

This study was intended to investigate the crosslinking characteristics of a new crosslinking agent-oxidized sodium alginate (ADA), which might provide an ideal biological crosslinking reagent for the construction of soft tissue bioprostheses. Glutaraldehyde and genipin, which have been typically used in developing bioprostheses, were used as controls. The porcine aortas were treated by these three crosslinking agents for 15 min to 72 h and the fixation index was determined. Subsequently, the mechanical property and cytocompatibility of fixed tissues were also tested. The results indicated that fixed tissues by ADA were comparable as glutaraldehyde and superior to genipin controls in fixative efficiency. It was also found that tissues fixed by ADA were comparable as genipin and superior to glutaraldehyde controls in cytocompatibility and were similar to natural tissues in mechanical property. The results of in vitro study demonstrated that ADA could be a promising crosslinking reagent for biological tissue fixation.
Alginates ; chemistry ; pharmacology ; Animals ; Aorta ; cytology ; metabolism ; Biocompatible Materials ; metabolism ; Cross-Linking Reagents ; chemistry ; pharmacology ; Extracellular Matrix ; metabolism ; Glucuronic Acid ; chemistry ; pharmacology ; Hexuronic Acids ; chemistry ; pharmacology ; Swine ; Tissue Engineering ; methods ; Tissue Fixation ; Tissue Scaffolds

White-rot fungus manganese peroxidase (MnP) oxidizes a wide range of substrates, rendering it an interesting enzyme for potential applications. The stability of MnP can be improved by immobilization. With sodium alginate, gelatin, or chitosan as a carrier, and glutaraldehyde as the crosslinking agent, MnP was co-immobilized using the embed-crosslinked method and the adsorb-crosslinked method. The immobilization conditions and the partial properties of the three immobilized enzymes were investigated. When compared with the free enzyme, the optimum pH values and the temperatures of the three immobilized MnPs carried by alginate, gelatin, and chitosan were respectively shifted from 7.0 to 5.0, 5.0, 3.0 and from 35 degrees C to 75 degrees C , 55 degrees , 75 degrees C . The thermostabilities of the three immobilized MnPs were considerably better than that of the native enzyme. The chitosan-decreased by less than 5% even after repeated use for 6 - 9 times. The ability of decolorizing azo dyes in static and shaky situation by gelatin-immobilized MnP approached to the free enzyme, and there was no loss of enzyme activity during 2 repeated batch reactions.
Adsorption ; Alginates ; chemistry ; metabolism ; Biocatalysis ; drug effects ; Chitosan ; chemistry ; metabolism ; Dose-Response Relationship, Drug ; Enzymes, Immobilized ; chemistry ; metabolism ; Fungal Proteins ; chemistry ; metabolism ; Gelatin ; chemistry ; metabolism ; Glucuronic Acid ; chemistry ; metabolism ; Glutaral ; pharmacology ; Hexuronic Acids ; chemistry ; metabolism ; Hydrogen-Ion Concentration ; Kinetics ; Peroxidases ; chemistry ; metabolism ; Schizophyllum ; enzymology ; Substrate Specificity ; Temperature

In the present study, a gastric retention floating system for Brucea javanica oil, composed of alginate and carrageenan, was prepared using ionotropic gelation. Parameters for floatability, drug load, encapsulation efficiency, bead morphology, in vitro release, and in vivo gastric retention were evaluated. The optimized formulation via Box-Behnken design consisted of 1.7% alginate (W/V), 1.02% carrageenan (W/V), 1.4% CaCO (W/V), and a gelling bath of pH 0.8. The alginate-carrageenan-Brucea javanica oil beads had a porous structure and exhibited up to 24 h of in vitro floatability with a load capacity of 45%-55% and an encapsulation efficiency of 70%-80%. A 6-h sustained release was observed in vitro. The beads had a prolonged gastric retention (> 60% at 6 h) in fasted rats, compared to non-floating beads (15% at 6 h), as measured by gamma scintigraphy with single-photon emission tomography/computed tomography (SPET/CT). In conclusion, the alginate-carrageenan-Brucea javanica oil system showed enhanced oil encapsulation efficiency, excellent floating and gastric retention abilities, and a favorable release behavior.
Alginates ; chemistry ; Animals ; Biological Availability ; Brucea ; chemistry ; Carrageenan ; chemistry ; Delayed-Action Preparations ; administration & dosage ; chemistry ; pharmacokinetics ; Drug Carriers ; chemistry ; Drug Delivery Systems ; methods ; Drug Evaluation, Preclinical ; Gastric Mucosa ; metabolism ; Glucuronic Acid ; chemistry ; Hexuronic Acids ; chemistry ; Microspheres ; Plant Oils ; administration & dosage ; chemistry ; pharmacokinetics ; Rats ; Rats, Sprague-Dawley

Transplantation of islet cells into diabetic patients is a promising therapy, provided that the islet cells are able to evade host immune rejection. With improved islet viability, this strategy may effectively reverse diabetes. We applied 2% calcium alginate to generate small and large capsules to encapsulate porcine neonatal pancreatic cell clusters (NPCCs) using an air-driven encapsulator. After encapsulation, the viability was assessed at 1, 4, 7, 14 and 28 days and secretion of functional insulin in response to glucose stimulation were tested at days 14 and 28. Selective permeability of the small alginate capsules was confirmed using various sizes of isothiocyanate-labeled dextran (FITC-dextran). Encapsulation of NPCCs was performed without islet protrusion in the small and large capsules. The viability of NPCCs in all experimental groups was greater than 90% at day 1 and then gradually decreased after day 7. The NPCCs encapsulated in large capsules showed significantly lower viability (79.50 +/- 2.88%) than that of naive NPCCs and NPCCs in small capsule (86.83 +/- 2.32%, 87.67 +/- 2.07%, respectively) at day 7. The viability of naive NPCCs decreased rapidly at day 14 (75.67 +/- 1.75%), whereas the NPCCs encapsulated in small capsules maintained (82.0 +/- 2.19%). After 14 and 28 days NPCCs' function in small capsules (2.67 +/- 0.09 and 2.13 +/- 0.09) was conserved better compared to that of naive NPCCs (2.04 +/- 0.25 and 1.53 +/- 0.32, respectively) and NPCCs in large capsules (2.04 +/- 0.34 and 1.13 +/- 0.10, respectively), as assessed by a stimulation index. The small capsules also demonstrated selective permeability. With this encapsulation technique, small capsules improved the viability and insulin secretion of NPCCs without islet protrusion.
Alginates/chemistry/metabolism ; Animals ; Animals, Newborn ; Capsules/chemistry ; Cell Survival ; Diabetes Mellitus/pathology/*therapy ; Disease Models, Animal ; Glucuronic Acid/chemistry/metabolism ; Graft Rejection/etiology/*prevention & control ; Hexuronic Acids/chemistry/metabolism ; Humans ; Insulin/secretion ; Islets of Langerhans/*metabolism/pathology ; Islets of Langerhans Transplantation/*methods ; Postoperative Complications/etiology/*prevention & control ; *Swine

OBJECTIVE: To determine the effects of sodiun aescinate on Bcl-2 and Caspase-3 protein expression and neuronal apoptosis after focal cerebral ischemia reperfusion injury in rats. METHODS: One hundred male Wistar rats were subjected to middle cerebral artery occlusion (MCAO) and reperfusion. The rats were divided randomly into 4 groups: sham-operated group and MCAO and reperfusion model groups which were randomly divided into control group, saline group, and sodium aescinate group. The immunohistochemistry staining and microscope image were used to observe the dynamic Bcl-2 and Caspase-3 protein expression in the ischemic penumbra after the reperfusion. Terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining was performed for the detection of apoptosis. RESULTS: Bcl-2 protein expression in the sodium aescinate group was significantly higher than that of the saline group and control group (P < 0.05). While Caspase-3 protein expression in the sodium aescinate group was then compared with those of the saline group and control group, and showed the difference was significant (P < 0.05). Compared with the saline group and control group, the number of apoptotic cells in the sodium aescinate group was significantly reduced (P < 0.01). CONCLUSION Sodium aescinate increases Bcl-2 protein expression and decreases Caspase-3 protein expression,through which it can protect the ischemia brain on reperfusion injury.
Alginates ; pharmacology ; Animals ; Apoptosis ; drug effects ; Brain Ischemia ; metabolism ; pathology ; Caspase 3 ; Caspases ; biosynthesis ; genetics ; Glucuronic Acid ; pharmacology ; Hexuronic Acids ; pharmacology ; Male ; Plants, Medicinal ; chemistry ; Proto-Oncogene Proteins c-bcl-2 ; biosynthesis ; genetics ; Random Allocation ; Rats ; Rats, Wistar ; Reperfusion Injury ; metabolism ; pathology ; Saponins ; pharmacology

AIMTo evaluate the hypoglycemic effect of chitosan-coated and sodium alginate-coated insulin liposomes after oral administration in mice.

METHODSInsulin-liposomes were prepared by reverse-phase evaporation. Chitosan and alginate coating was carried out by mixing liposomal suspension with chitosan and sodium alginate solutions, followed by incubation. The particle size and morphology of insulin-liposomes were determined using laser light scattering instrument and transmission electron microscopy (TEM). The entrapment efficiency was analyzed using HPLC and ultracentrifuge. The protection of insulin from peptic and tryptic digestion was studied with HPLC. The hypoglycemic effects of polysaccharide-coated insulin liposomes were investigated using the glucose oxidase method after oral administration in mice.

RESULTSThe particle size of uncoated, chitosan-coated and alginate-coated insulin-liposomes was (138 +/- 31) nm, (230 +/- 20) nm and (266 +/- 19) nm, respectively. All insulin-liposomes were of spherical or ellipsoidal shape. The entrapment efficiencies were 81.6%, 73.5% and 68.7%, respectively. Insulin was protected from tryptic digestion by chitosan-coated liposomes and protected from peptic digestion by alginate-coated liposomes. The hypoglycemic effects of insulin-liposomes, coated with 0.1% chitosan and 0.1% sodium alginate, were observed.

CONCLUSIONChitosan-coated and sodium alginate-coated liposomes were shown to reduce peptic or tryptic digestion on insulin, and enhance enteral absorption of insulin.

Administration, Oral ; Alginates ; Animals ; Blood Glucose ; metabolism ; Chitin ; analogs & derivatives ; chemistry ; Chitosan ; Delayed-Action Preparations ; Drug Carriers ; Drug Delivery Systems ; Glucuronic Acid ; Hexuronic Acids ; Hypoglycemic Agents ; administration & dosage ; pharmacology ; Insulin ; administration & dosage ; pharmacology ; Liposomes ; Male ; Mice ; Particle Size ; Random Allocation ; Technology, Pharmaceutical ; methods