Production of extracellular bifidogenic growth stimulator (BGS) from Propionibacterium shermanii using a bioreactor system with a microfiltration module and an on-line controller for lactic acid concentration

Production of a bifidogenic growth stimulator (BGS) by Propionibacterium freudenreichii subsp. shermanii (Propionibacterium shermanii) using lactic acid as a carbon source was investigated using different cultivation methods. When a continuous bioreactor system with a filtration device was used at a dilution rate of 0.075 h(-1), the average BGS concentration was 2.4 mg/l, which corresponds to a BGS productivity per cultivation time of 1.8 x 10(-1) mg x l(-1) x h(-1). The BGS productivity per cultivation time in continuous cultivation with filtration was 1.9-fold that (9.4 x 10(-2) mg x l(-1).h(-1)) in a conventional batch cultivation. In fed-batch cultivation with feed-back control using an on-line lactic acid controller with a lactic acid biosensor, it was possible to prevent substrate inhibition by maintaining the lactic acid concentration in culture broth low at 3.3 g/l, and an enhanced BGS production (31 mg/l) was successfully attained. The BGS productivity per cultivation time (2.1x10(-1) mg x l(-1) x h(-1)) in the fed-batch cultivation with feed-back control was 2.2-fold that in the conventional batch cultivation. A new bioreactor system was developed by coupling a continuous bioreactor system with a filtration device to an on-line lactic acid controller. Using the new bioreactor system, we produced BGS continuously at a high level of 47 mg/l. The BGS productivities per cultivation time (3.5 mg.l(-1) x h(-1)) and the total volume of medium used (1.7 x 10(-1) mg x l(-1) x h(-1)) obtained in the new bioreactor system were 37-fold and 2.1-fold those in the conventional batch cultivation, respectively. These results described above clearly demonstrate the positive effects of both the continuous filtration for removal of metabolites (propionic and acetic acids) inhibitory to cell growth and feed-back control of lactic acid concentration in the culture broth on BGS production by P. shermanii. This paper is the first report on BGS production by the propionic acid bacterium using lactic acid as a carbon source.     

Effects of inulin and oligofructose on the rheological characteristics and probiotic culture survival in low-fat probiotic ice cream

ABSTRACT:  The effects of supplementation of oligofructose or inulin on the rheological characteristics and survival of Lactobacillus acidophilus La-5 and Bifidobacterium animalis Bb-12 in low-fat ice cream stored at –18 °C for 90 d were studied. Addition of oligofructose or inulin to ice cream mix significantly increased apparent viscosity and overrun and developed the melting properties in ice cream during storage ( P < 0.05). However, the highest increase in firmness, the lowest change in melting properties, and the longest 1st dripping time were obtained in probiotic ice cream containing inulin ( P < 0.05). Some textural properties have also improved especially by the end of storage. Freezing process caused a significant decrease in the viability of Lactobacillus acidophilus La-5 and Bifidobacterium animalis Bb-12 ( P < 0.05). Oligofructose significantly improved the viability of L. acidophilus La-5 and B. animalis Bb-12 in ice cream mix ( P < 0.05). Although the viable numbers for both bacteria decreased throughout the storage, the minimum level of 10⁶ CFU/g was maintained for B. animalis Bb-12 in only ice cream with oligofructose during storage.     

Preparation and Analysis of α-1,6 Glucan as a Slowly Digestible Carbohydrate

Carbohydrate materials that produce lower postprandial blood glucose increase are required for diabetic patients. To develop slowly digestible carbohydrates, the effect of degree of polymerization (DP) of α-1,6 glucan on its digestibility was investigated in vitro and in vivo. We prepared four fractions of α-1,6 glucan composed primarily of DP 3–9, DP 10–30, DP 31–150, and DP 151+ by fractionating a dextran hydrolysate. An in vitro experiment using digestive enzymes showed that the glucose productions of DP 3–9, DP 10–30, DP 31–150, and DP 151+ were 70.3, 53.4, 28.2, and 19.2 % in 2 h, and 92.1, 83.9, 39.6, and 33.3 % in 24 h relative to dextrin, respectively. An in vivo glycemic response showed that the incremental area under the curve (iAUC) of blood glucose levels of α-1,6 glucan with DP 3–9, DP 10–30, DP 31–150, and DP 151+ were 99.5, 84.3, 65.4, and 40.1 % relative to dextrin, respectively. These results indicated that α-1,6 glucan with higher DP had stronger resistance to digestion and produced a smaller blood glucose response. DP 10–30 showed significantly lower maximum blood glucose levels than dextrin; however, no significant difference was observed in iAUC, indicating that DP 10–30 was slowly digestible. In addition, α-1,6 glucan was also produced using an enzymatic reaction with dextrin dextranase (DDase). This produced similar results to DP 10–30. The DDase product can be synthesized from dextrin at low cost. This glucan is expected to be useful as a slowly digestible carbohydrate source.     

Prevalence and characterization of perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCA) directed against HMG1 and HMG2 in ulcerative colitis (UC)

To examine the structural relationship among autoantibodies produced by individuals with anti-GBM antibody-mediated disease, a polyclonal anti-idiotype directed against human anti-alpha3(IV)NC1 antibodies was produced and then used to study autoantibodies from other patients. For this purpose, anti-alpha3(IV)NC1 antibodies (anti-GBM), derived from a single patient (LL) with high titer and typical anti-GBM antibody specificity, were isolated using recombinant alpha3(IV)NC1-sepharose affinity chromatography. Following hyperimmunization of rabbits with anti-GBM IgG, irrelevant rabbit anti-human IgG antibodies were removed from the antiserum using a human IgG-sepharose column. The rabbit anti-alpha3(IV)NC1 antibodies (anti-Id GBM) effluent bound to human anti-GBM antibodies, but it did not bind to either normal human IgG or recombinant alpha3(IV)NC1 protein. The Id-anti-Id interaction was conformationally dependent on intact heavy and light chains of the anti-alpha3(IV)NC1 antibodies (ELISA and Western blotting). A competitive immunoassay was developed to evaluate structural and potential genetic relationships among anti-alpha3(IV)NC1 antibodies from different patients. All patients tested (9 of 9) had a substantial fraction (producing > 50% inhibition) of anti-GBM antibodies expressing Id-GBM. The results indicate that shared determinants are expressed by anti-GBM antibodies from different individuals, and they raise the possibility that common genetic elements are used to encode them. These regions are potential targets for design of reagents to regulate autoreactive B cells and/or interfere with pathogenic antibody-GBM interactions, in individuals with anti-GBM antibody mediated diseases.     

Movement and metabolism of S-benzyl O,O-diisopropyl phosphorothiolate (Kitazin P) and O-ethyl S,S-diphenyl phosphorodithiolate (edifenphos) in various types of soils

Movement and Metabolism of 32P and 35S-double labeled Kitazin P (S-benzyl O,O-diisopropyl phosphorothiolate) and 35S-labeled edifenphos (O-ethyl S,S-diphenyl phosphorodithiolate) were examined with three types of soils, sandy loam, alluvial clay loam, and volcanic ash loam. Vertical movement of both the compounds in soil column was different with soil types, and the order of mobility in soil column was as follows: sandy loam greater than alluvial clay loam greater than volcanic ash loam. Persistence of edifenphos in soil was shorter than that of Kitazin P. Main degradation products at the initial stage of metabolism were S,S,S-triphenyl phosphorotrithiolate, O,O-diethyl S-phenyl phosphorothiolate, S-phenyl dihydrogen phosphorothiolate and diphenyl disulfide in edifenphos and O,O-diisopropyl hydorgen phosphorothioate in Kitazin P. Sulfur atom of Kitazin P was found in sulfuric acid at a minor level through dibenzyl disulfide and toluene-alpha-sulfonic acid, and that of edifenphos was converted to sulfuric acid through diphenyl disulfide and benzenesulfonic acid. Kitazin P under flooded condition of alluvial clay loam was slightly more persistent as compared with upland condition. Sterilized condition of Kitazin P did not cause any appreciable degradation throughout the experimental period, but such condition did not necessarily prevent the degradation of edifenphos.     

Different expression of Bcl-2 protein in gastric adenomas and carcinomas

In order to cast light on the possible role of bcl-2 protein (Bcl-2) expression in gastric tumorigenesis, 33 cases of gastric adenomas and carcinomas originating from the same stomachs were immunohistochemically investigated for Bcl-2 protein (Bcl-2) expression, accumulation of p53 protein and cell proliferation as determined by the Ki-67 labeling index (LI). Bcl-2 expression was detected in 24/33 (72.7%) adenomas and in 6/33 (18.2%) carcinomas, the difference being statistically significant (P = 0.0001). Only 4 of 33 (12.1%) cases exhibited expression in both adenoma and carcinoma lesions in the same stomachs. Immunoreactivity was decreased in areas of cellular and structural atypia in adenoma lesions (P < 0.008), and appeared to be positively linked to the tumor progression and the degree of differentation in carcinomas, although it did not reach statistical significance. Accumulation of p53 protein was rare in the adenomas but was found in 15/33 (45.5%) of carcinoma lesions, with a significant dissociation from Bcl-2 immunoreactivity. No apparent relation between Ki-67 LI and either adenoma grading or carcinoma typing was noted, although average Ki-67 LI of the highest labeling areas in carcinomas was statistically higher than in adenomas (P = 0.0001). These results indicate that the regulation of Bcl-2 expression may differ between gastric adenomas and carcinomas, may be correlated with tumor differentiative features. In addition, p53 accumulation may play an important role in the onset of malignancy.     

Relationship between imaging and pathological features and clinical factors in surgical cases of temporal lobe epilepsy]

The advantages of the free TRAM flap over the conventional Tram flap are known. The use of its main pedicle--the deep inferior epigastric system--improves the blood supply, decreasing the risk of skin and fat necrosis. The harvesting of 5-7 cm of muscle, and the preservation of its lateral border decreases the risk of abdominal wall bulge or hernias. Delayed breast reconstructions in patients submitted to radiotherapy were performed by end to side anastomosis between flap vessels and axillary vessels, avoiding the thoracodorsal irradiated vessels, and improving the blood flow. Ten patients were submitted to breast reconstruction by free TRAM flaps. There was one total flap necrosis, and one delayed healing around the periumbilical suture. Neither skin nor fat necrosis were seen. One patient developed an abdominal wall bulge. Two patients presenting tumor metastasis abandoned the plastic surgery outpatient clinic. Two patients refused the nipple-areolar complex (NAC) reconstruction. The outcome of five NAC reconstructions was very good, breasts being symmetrical without an opposite breast operation.