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1.
G. I. Novik N. I. Astapovich Zh. N. Bogdanovskaya N. E. Ryabaya 《Applied Biochemistry and Microbiology》2000,36(1):90-95
Production of Enterobifidin includes the stages of preparation of culture media, reparation of lyophilizedBifidobacterium adolescentis MS-42 culture, preparation of starters, cultivation of bacteria in fermenters, biomass conservation, and its biological control.
The preparation contains physiologically active bifidobacterium cells with high activities of growth(μ = 0.7 h−1,g = 1.0 h) and acid formation (titratable acidity is ∼120–140°T; acetate concentration, 0.50–0.75%; and lactate concentration,
0.33–0.50%). The antagonistic activity of these bacteria towardsEscherichia coli 08,E. coli 086,E. coli 015,E. coli 0115, andE. coli 0101 amounts to 98.2; toProteus vulgaris 102, to 87.2; andStaphylococcus aureus 209p, to 83.2%. The bifidobacteria (with a titer of ∼109 CFU/ml) remained viable for two to five months. 相似文献
2.
Microelement preparations obtained in the course of processing of flint powder stimulate the biological activity of Bifidobacterium adolescentis 94 BIM, grown on complex and synthetic nutritive media. The composition of the microelement preparations differed in the content of cations and anions. Introduction of the preparations into the cultures of physiologically active or anabiotic forms of bifidobacteria changed the parameters of exponential growth: compared to controls, the cultures were characterized by increased specific growth rate and decreased generation time. In the presence of microelements, the development of populations of bifidobacteria was associated with more pronounced accumulation of metabolic products (acetate, lactate, and ethanol). Introduction of microelement preparations increased the rate of synthesis of the extracellular proteinase (maximum content of the enzyme was observed after 3 h, whereas control cultures attained this level only after 6 h). 相似文献
3.
The cell-bound polysaccharides (PSs) of Bifidobacterium adolescentis 94 BIM were stripped from the cell surface with 2% sodium dodecyl sulfate (SDS), 1.5% Cetavlon, and 1% Triton X-100 and purified by precipitation with 5 volumes of ethanol. According to the extraction conditions used, the polysaccharide preparations were designated as PS-SDS-6 degrees C, PS-SDS-100 degrees C, PS-Cet, and PS-Trit. The gel-permeation chromatography of the first two preparations with the use of a Bio-Gel P-10 column and 1% acetic acid as the eluant yielded two peaks, F1 and F2, which contained carbohydrates and no phosphorus. All polysaccharides were primarily composed of glucose and galactose. The polysaccharides PS-Cet and PS-Trit were found to be branched and contain glucose residues at the terminal position, position 4, and position 6, and galactose residue at position 3. PS-SDS-6 degrees C has a glucose residue at position 4. 相似文献
4.
Novik KL Nimmrich I Genc B Maier S Piepenbrock C Olek A Beck S 《Current issues in molecular biology》2002,4(4):111-128
Epigenetics is one of the key areas of future research that can elucidate how genomes work. It combines genetics and the environment to address complex biological systems such as the plasticity of our genome. While all nucleated human cells carry the same genome, they express different genes at different times. Much of this is governed by epigenetic changes resulting in differential methylation of our genome--or different epigenomes. Individual studies over the past decades have already established the involvement of DNA methylation in imprinting, gene regulation, chromatin structure, genome stability and disease, especially cancer. Now, in the wake of the Human Genome Project (HGP), epigenetic phenomena can be studied genome-wide and are giving rise to a new field, epigenomics. Here, we review the current and future potential of this field and introduce the pilot study towards the Human Epigenome Project (HEP). 相似文献
5.
It is well established that the vast majority of proteins of all taxonomical groups and species are initiated by an AUG codon, translated into the amino acid methionine (Met). Many attempts were made to evaluate the importance of the sequences surrounding the initiation codon, mostly focusing on the RNA sequence. However, the role and importance of the amino acids following the initiating Met residue were rarely investigated, mostly in bacteria and fungi. Herein, we computationally examined the protein sequences of all major taxonomical groups represented in the Swiss-Prot database, and evaluated the preference of each group to specific amino acids at the positions directly following the initial Met. The results indicate that there is a species-specific preference for the second amino acid of the majority of protein sequences. Interestingly, the preference for a certain amino acid at the second position changes throughout evolution from lysine in prokaryotes, through serine in lower eukaryotes, to alanine in higher plants and animals. 相似文献
6.
This study describes a novel isolation procedure for major glycolipids from Bifidobacterium adolescentis 94 BIM. The procedure consists of the use of supercritical carbon dioxide (scCO(2)) with hydro-methanolic solution as co-solvent. The major glycolipids were isolated using the following operating conditions: pressure, 30 MPa, co-solvent concentration, 10% (9:1, methanol/water, v/v), CO(2) flow rate, 5 g/min, extraction time and temperature, 2h and 55 degrees C, respectively. The reference glycolipids sample was prepared by classical organic solvent extraction followed by chromatographic purification. All isolates were characterized by TLC and the major glycolipids additionally by enzyme linked immunosorbent (ELISA). Sixty milligrams of glycolipids with similar immunoreactivity as the reference glycolipids were isolated from 1g of freeze-dried biomass (6% of yield). 相似文献
7.
Alginate-PLL microencapsulation: effect on the differentiation of embryonic stem cells into hepatocytes 总被引:8,自引:0,他引:8
The emergence of hepatocyte based clinical and pharmaceutical technologies, has been limited by the absence of a stable hepatocyte cell source. Embryonic stem cells may represent a potential solution to this cell source limitation problem since they are highly proliferative, renewable, and pluripotent. Although many investigators have described techniques to effectively differentiate stem cells into a variety of mature cell lineages, their practicality is limited by: (1) low yields of fully differentiated cells, (2) absence of large scale processing considerations, and (3) ineffective downstream enrichment protocols. Thus, a differentiation platform that may be modified to induce and sustain differentiated cell function and scaled to increase differentiated cell yield would improve current stem cell differentiation strategies. Microencapsulation provides a vehicle for the discrete control of key cell culture parameters such as the diffusion of growth factors, metabolites, and wastes. In addition, both cell seeding density and bead composition may be manipulated. In order to assess the feasibility of directing stem cell differentiation via microenvironment regulation, we have developed a murine embryonic stem cell (ES) alginate poly-l-lysine microencapsulation hepatocyte differentiation system. Our results indicate that the alginate microenvironment maintains cell viability, is conducive to ES cell differentiation, and maintains differentiated cellular function. This system may ultimately assist in developing scalable stem cell differentiation strategies. 相似文献
8.
G. I. Novik A. A. Samartsev N. I. Astapovich M. A. Kavrus A. N. Mikhalyuk 《Applied Biochemistry and Microbiology》2006,42(2):166-172
Adaptation of bifidobacteria and lactic acid bacteria to nutrient media with increased concentrations of bile (1%) and protein substrates of animal origin allowed the variants resistant to bile and displaying a high production of proteolytic enzymes (active within the pH range of 2.5–9.0) to be selected. Administration of the preparations involving the selected bifidobacteria and lactic acid bacteria assisted in the normalization of the intestinal microflora and activation of protein metabolism in the organism of animals. Specifically, it increased the total protein level in blood serum and redistributed protein fractions, increasing the content of globulins and decreasing albumin concentration. 相似文献
9.
Novik GI Samartsev AA Astapovich NI Kavrus MA Mikhaliuk AN 《Prikladnaia biokhimiia i mikrobiologiia》2006,42(2):187-194
Adaptation of bifidobacteria and lactic acid bacteria to nutrient media with increased concentrations of bile (1%) and protein substrates of animal origin allowed the variants resistant to bile and displaying a high production of proteolytic enzymes (active within the pH range of 2.5-9.0) to be selected. Administration of the preparations involving the selected bifidobacteria and lactic acid bacteria assisted in the normalization of the intestinal microflora and activation of protein metabolism in the organism of animals. Specifically, it increased the total protein level in blood serum and redistributed protein fractions, increasing the content of globulins and decreasing albumin concentration. 相似文献
10.
Richard A. Koup Mario Roederer Laurie Lamoreaux Jennifer Fischer Laura Novik Martha C. Nason Brenda D. Larkin Mary E. Enama Julie E. Ledgerwood Robert T. Bailer John R. Mascola Gary J. Nabel Barney S. Graham the VRC VRC Study Teams 《PloS one》2010,5(2)