Fibronectin suppresses lipopolysaccharide-induced liver damage and promotes the cytoprotection abilities of hepatocyte-like cells derived from human bone marrow mesenchymal stem cells.

We isolated mesenchymal stem cells (MSCs) from adult human bone marrow. By using reverse-transcription polymerase chain reactions, we confirmed that MSCs possessed the potential to differentiate into hepatocyte-like cells (MSC-HLCs) with the expression of hepatocyte-specific marker genes. We further observed that fibronectin (FN) treatment significantly inhibited lipopolysaccharide (LPS)-induced apoptotic activities in FN-treated MSC-HLCs, as detected by caspase 3 enzyme-linked immunosorbent (ELISA) and terminal dUTP nick-end labeling (TUNEL) assays (P<.05). The FN-treated MSC-HLCs were transplanted into SCID mice with or without LPS injection. This study demonstrated that FN treatment improved liver function repair and survival rates among LPS-treated SCID mice.

A repeated batch process for cultivation of Bifidobacterium longum.

A repeated batch process was performed to culture Bifidobacterium longum CCRC 14634. An on-line device, oxidation-reduction potential (ORP), was used to monitor cell growth and uptake of nutrients in the culture. The ORP of the culture medium decreased substantially during fermentation until nutrients were depleted. Six cycles of batch fermentation using ORP as a control parameter were successfully carried out. As soon as ORP remained constant or increased, three-quarters of the broth was removed, and the same volume of fresh medium was fed to the fermenter for a new cycle of cultivation. Average cell concentrations of 1.9 x 10(9) and 3.4 x 10(9) cfu ml(-1) for repeated batch fermentation in MRS (Lactobacilli MRS broth) and WY (containing whey hydrolyzates, yeast extract, l-cysteine) medium, respectively, were achieved. Cell mass productivities for batch, fed-batch and repeated batch fermentation using MRS medium were 0.51, 0.41, and 0.64 g l(-1) h(-1), respectively, and those for batch and repeated batch using WY medium were 0.76, 0.99 g l(-1) h(-1), respectively. The results indicate a possible industrial process to culture Bifidobacteria sp.

Immobilization of beta-fructofuranosidases from Aspergillus on methacrylamide-based polymeric beads for production of fructooligosaccharides.

beta-Fructofuranosidases from Aspergillus niger ATCC 20611 and Aspergillus japonicus TIT-KJ1 were purified and immobilized covalently onto methacrylamide-based polymeric beads. The porous, oxriane-containing support was reactive and could bind enzymes in a buffered solution at room temperature with a density up to 0.4 mg of protein g-1 of support with 100% immobilized yield. Neither the optimum temperature for the highest enzymatic activities nor the batch reaction pattern for fructooligosaccharides formation catalyzed by beta-fructofuranosidases was changed by immobilization. The amount of fructooligosaccharides produced from 50% (w/w) sucrose solution using the prepared immobilized enzymes was determined to be approximately 60% of the total sugars in the reaction mixtures. This level of fructooligosaccharides produced by the immobilized enzymes was comparable to that resulting from processes employing other immobilized biocatalysts as shown in the literature. The fraction of total fructooligosaccharides presented in the final mixture increased with the initial sucrose concentration, while fractions of glucose and fructose decreased with an increase sucrose concentration.

Purification and characterization of beta-fructofuranosidase from Aspergillus japonicus TIT-KJ1.

A beta-fructofuranosidase (EC 3.2.1.26) was purified to homogeneity from Aspergillus japonicus TIT-KJ1. The enzyme had an optimum pH for activity of 5.4 and pH stability at 7.0-8.4. The optimum temperature at pH 5.4 was 60 degrees C. The enzyme had a molecular weight of 236,000 with two subunits and an isoelectric point of pH 4.0. The enzyme was inactivated by 5 mM Hg2+ and Ag+. The enzyme had a high transfructosylating activity. Treatment of 50% (w/v) sucrose with the enzyme under optimum conditions afforded more than 55% fructooligosaccharides.