Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0847097 (acidity)
 15,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Microbial fish silage was produced from a mixture of several fish species that belong to the shrimp by-catch. They were mixed with molasses, fruits (pineapple and papaya), sorbate and a starter of Lactobacillus plantarum ATCC8014. Process was evaluated by pH, acidity, consistency, exudate liquid, non-protein nitrogen, total volatile bases, microbial and toxicological tests. Results indicated that acid production and pH reduction occurs during the first two days of processing, later these values were maintained stable during 64 storage days. Total volatile bases increased during storage period. Consistency, non-protein nitrogen and exudate liquid showed that hydrolysis and liquefaction occurs during the first 8 days of processing. Raw material showed high counts of aerobic mesophilic and psicrotrophic organisms, in addition to Pseudomonas, coliform and S. aureus. However silage showed only a few aerobic mesophilic organisms due to low pH values and development of lactic acid bacteria. Silage dehydration reduces possibilities of microbial growth, and only spores of Bacillus were observed. Low levels of lead, mercury and chrome were detected in the dry silage. Proximal analysis values did not change during process and storage period.
 ...
PMID:[Microbial silage production from eviscerated fish]. 877 24

Microbial Fish Silage was produced from under-utilized fish mixed with juice and waste fruits (pineapple and papaya) at 35 degrees C. Six different products were elaborated as following: A: fish muscle with pineapple juice; B: fish muscle with fruit wastes; C: gutted fish with pineapple juice; D: gutted fish with fruit wastes; E: whole fish with pineapple juice; F: whole fish with fruit wastes. Process development was evaluated by measuring: pH, acidity, non-protein nitrogen, consistency and exudate liquid. Results indicated a slow decrease in pH value and production of acidity during 20 storage days. The addition of fruits to silage did not have any effect on these values. Silage liquefaction or hydrolysis was related to the following parameters: consistency, non-protein nitrogen and exudate liquid. The addition of fruits was related to silage liquefaction or hydrolysis, and it was measured by the consistency. Exudate liquid and non-protein nitrogen increased during storage time. However silage made from whole fish showed highest values in those parameters than other processing conditions. This results suggested that hydrolysis involve first enzymes from guts and second enzymes from muscle and head. Pineapple juice did not contribute to hydrolysis process. Mainly sensory changes in the silage occurs during first 24 hours and they were related to chemical changes. Proximal analysis did not change during silage process and microbial counts indicated the freshness of raw material used i this study.
 ...
PMID:[Effect of the addition of tropical fruits--pineapple (Ananas comosus) and papaya (Carica papaya)--on the production of biological silage from fish]. 877 25

An attempt was carried out for prolongation of the shelf-life of Mozzarella cheese by incorporation of potassium sorbate into the cheese. Three manufacturing techniques were used: a) addition of potassium sorbate to kneading water (at level of 6%), b) addition during brine salting (at level of 0.5%) and c) dipping the cheese into potassium sorbate solution (6%) directly prior to packaging. Control cheese was made without potassium sorbate treatment. The resulting cheeses were divided into two portions, one of which was contaminated with Penicillium roqueforti and then packaged, while the second one was packaged without contamination. Both were stored at refrigerator (5 +/- 1 degree C) temperature and analysed periodically until spoilage. The results showed that treatment with potassium sorbate did not affect the organoleptic properties of the cheeses, except that a slight objectionable bitter flavour was observed in fresh cheeses treated with sorbate using the techniques of dipping or in brine salting then it was disappeared during storage. However, the overall acceptabilities of the sorbate-treated cheese were increased up to 10 weeks of storage compared with 4 weeks for untreated cheeses. Treatment with potassium sorbate in kneading water or brine appeared to be more effective than dipping. Addition of potassium sorbate inhibited microbial growth, especially that of moulds and yeasts. The sorbate-treated cheeses had higher moisture, pH values and lower acidity than the control. Fat, salt and total nitrogen were unaffected during storage. Levels of soluble N, non-protein N and total volatile fatty acids in sorbate-treated cheeses were slightly higher than in the control. Furthermore, addition of potassium sorbate increased the meltability and improved the fat leakage of Mozzarella cheese.
 ...
PMID:Prolongation of the keeping quality of Mozzarella cheese by treatment with sorbate. 881 83

Detailed nutrient requirements were determined to maximise efficacy of a sulphate-reducing bacterial mixed culture for biotechnological removal of sulphate, acidity and toxic metals from waste waters. In batch culture, lactate produced the greatest biomass, while ethanol was more effective in stimulating sulphide production and acetate was less effective. The presence of additional bicarbonate and H2 only marginally stimulated sulphide production. The sulphide output per unit of biomass was greatest using ethanol as substrate. In continuous culture, ethanol and lactate were used directly as efficient substrates for sulphate reduction while acetate yielded only slow growth. Glucose was utilised following fermentation to organic acids and therefore had a deleterious effect on pH. Ethanol was selected as the most efficient substrate due to cost and efficient yield of sulphide. On ethanol, the presence of additional carbon sources had no effect on growth or sulphate reduction in batch culture but the presence of complex nitrogen sources (yeast extract or cornsteep) stimulated both. Cornsteep showed the strongest effect and was also preferred on cost grounds. In continuous culture, cornsteep significantly improved the yield of sulphate reduced per unit of ethanol consumed. These results suggest that the most efficient nutrient regime for bioremediation using sulphate-reducing bacteria required both ethanol as carbon source and cornsteep as a complex nitrogen source.
 ...
PMID:A comparison of carbon/energy and complex nitrogen sources for bacterial sulphate-reduction: potential applications to bioprecipitation of toxic metals as sulphides. 898 95

Recently great interest has arisen in the synthesis of combinatorial libraries, and this technology provides a significant partner to contemporary strategies in rational design and lead discovery. By simple combination of a given set of building blocks, high numbers of different molecules are produced simultaneously, increasing the possibility of discovery of a lead compound in a limited time. One direction of research in this field focuses on the synthesis of libraries composed of modified amino acids. Here, the synthesis and characteristics of some building blocks derived from ornithine are described. The synthesis is based on the acylation/sulfonation of the copper complex of ornithine by aroyl and arylsulfonyl chlorides exemplified by 2-thiophenecarbonyl chloride, p-toluenesulfonyl chloride and 8-quinolinesulfonyl chloride. To evaluate the potential use of these modified alpha-amino acids as component in an oligopeptide library, all three derivatives were incorporated in a hexapeptide with a random sequence using a standard coupling procedure (DIC/HOBt/DIEA). Depending upon the acidity of the amido hydrogen on the delta-nitrogen, competition between intramolecular cyclization and peptide bond formation was observed. The higher the acidity, the more pronounced is this side reaction. Coupling conditions for peptide formation were optimized so that the newly described amino acid based building blocks are suitable for incorporation into libraries consisting of unnatural amino acids. The outlined procedures open up a broad avenue of possibilities for creation of diversity into peptidic libraries.
 ...
PMID:alpha-Amino acids derived from ornithine as building blocks for peptide synthesis. 914 14

In order to address the role that the ambient air pollution mix, comprised of gaseous pollutants and various physical and chemical measures of particulate matter, plays in exacerbating cardiorespiratory disease, daily measures of fine and coarse particulate mass, aerosol chemistry (sulfates and acidity), and gaseous pollution (ozone, nitrogen dioxide, sulfur dioxide, and carbon monoxide) were collected in Toronto, Ontario, Canada, in the summers of 1992, 1993, and 1994. These time series were then compared with concurrent data on the number of daily admissions to hospitals for either cardiac diseases (ischemic heart disease, heart failure, and dysthymias) or respiratory diseases (tracheobronchitis, chronic obstructive long disease, asthma, and pneumonia). After adjusting the admission time series for long-term temporal trends, seasonal variations, the effects of short-term epidemics, day of the week effects, and ambient temperature and dew point temperature, positive associations were observed for all ambient air pollutants for both respiratory and cardiac diseases. Ozone was least sensitive to adjustment for the gaseous and particulate pollution measures. However, the association between the health outcomes and carbon monoxide, fine and coarse mass, sulfate levels and aerosol acidity could be explained by adjustment for exposure to gaseous pollutants. Increases in ozone, nitrogen dioxide, and sulfur dioxide equivalent to their interquartile ranges corresponded to an 11% and 13% increase in daily hospitalizations for respiratory and cardiac diseases, respectively. The inclusion of any one of the particulate air pollutants in multiple regression models did not increase these percentages. Particle mass and chemistry could not be identified as an independent risk factor for the exacerbation of cardiorespiratory diseases in this study beyond that attributable to climate and gaseous air pollution. We recommend that effects of particulate matter on health be assessed in conjunction with temporally covarying gaseous air pollutants.
 ...
PMID:The role of particulate size and chemistry in the association between summertime ambient air pollution and hospitalization for cardiorespiratory diseases. 928 96

Gas exchange between blood in the middle ear (ME) mucosa and ambient ME gas may be limited by diffusion through tissue or blood perfusion. In order to study the limiting factors in ME gas exchange, a hole was drilled in the bulla of 14 anesthetized guinea pigs through which a mass spectrometer probe was inserted and sealed in place. The rate at which oxygen (O2), carbon dioxide (CO2), nitrogen, and argon concentrations changed toward their steady state values was recorded. From the exponential fitted curves, gas rate constants (Kg) were calculated. The ratio KCO2/KO2 was 4:1, which is lower than expected from a diffusion-limited process in an aqueous compartment. The different rate ratios of CO2 and O2 indicate a diffusion-limited process. However, the deviation of the KCO2/KO2 ratio from that expected in aqueous solutions may indicate the involvement of a lipid compartment in gas exchange or other physiological mechanisms such as local acidity.
 ...
PMID:Rate of gas exchange in the middle ear of guinea pigs. 952 39

Changes in pH in the process of the induced autolysis of salmonellae and Escherichia coli were studied. The induced autolysis of enterobacterial populations was studied in connection with the acidity values of the medium in which the process was carried out. The pH of extracellular fluid, the optical density of cell suspension, the content of total protein and amino nitrogen were analyzed. Enterobacterial populations were found to be capable of the self-regulation of the acidity of the medium in the process of induced autolysis. The study revealed that the most Intensive autolysis of bacteria took place when the process was carried out in extreme alkaline values of pH.
 ...
PMID:[The effect of the pH of the medium on induced autolysis in populations of enterobacteria]. 978 88

Growth of, and acid production by Bifidobacterium lactis and Lactobacillus acidophilus using ovine and caprine milk as media were evaluated for their potential use in cheese-making. A protein hydrolysate (MHP, obtained from incubation of bovine milk with protease) or a mixture of free amino acids (FAA, similar to the amino acid fraction of MHP) was added as a nitrogen enrichment source. Bifidobacterium lactis and Lact. acidophilus were inoculated at 50 ml l-1 and incubated at 37 degrees C with growth supplements added at ratios in the range 25-50 ml l-1. The maximum viable counts of Bif. lactis were lower in plain ovine and caprine milk than in nitrogen-enriched milk, and MHP was a better growth promoter than FAA. A similar trend was observed with the acidity values developed, and attempts to correlate growth with acidity were successfully performed. The highest uptake rates of amino acids in ovine milk were observed for lysine, isoleucine, leucine and proline, but only isoleucine was taken up at a similar rate in caprine milk. Final bacterial viable counts of Lact. acidophilus in the plain and enriched forms of ovine milk did not differ greatly from each other, although FAA was statistically a better growth promoter than MHP. Unlike results in ovine milk, cultures of Lact. acidophilus in caprine milk exhibited drops of 1-1.5 log cycles in viable cell counts by 24 h of fermentation, irrespective of the nature of the nitrogen source. Parallel studies indicated that the excess of fatty acid residues in caprine milk could be responsible for the poor growth of Lact. acidophilus.
 ...
PMID:Use of small ruminants' milk supplemented with available nitrogen as growth media for Bifidobacterium lactis and Lactobacillus acidophilus. 983 Jan 19

The present investigation studied the effects of cysteine, whey powder, whey protein concentrate, acid casein hydrolysates, or tryptone on the viability of Streptococcus thermophilus, Lactobacillus acidophilus, and bifidobacteria. Changes in pH, titratable acidity, redox potential, and viability of bacteria were monitored during 24 h of fermentation and refrigerated storage (4 degrees C) of yogurt for 35 d. The incubation time that was needed to reach pH 4.5 was considerably affected by the added ingredients. Also, the drop in pH or the increase in acidity and redox potential was dependent on the added ingredients. The addition of cysteine, whey protein concentrate, acid casein hydrolysates, or tryptone improved the viability of bifidobacteria to a variable extent, but whey powder failed to improve their viability. The morphology of S. thermophilus, as shown by electron microscopy, was affected by cysteine at 500 mg/L, possibly as a result of reduced redox potential. Sodium dodecyl sulfate-PAGE and amino acid analyses suggested that the nitrogen source in the form of peptides and amino acids improved the viability of bifidobacteria in yogurt made with a commercial ABT (Lactobacillus acidophilus, bifidobacteria, and Streptococcus thermophilus) starter culture, which showed a dramatic decline in the counts of this organism in previous studies.
 ...
PMID:Ingredient supplementation effects on viability of probiotic bacteria in yogurt. 983 22


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>