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Objective: To analyze the state-of-the-art technology and the application of the fermentation process, in order to increase the protein value of prickly pear (Opuntia ficus-indica), as a source of fodder, in three technological levels. Design/Methodology/Approach: The technological parameters and mechanization level of three fermenters —employed to increase the protein value of prickly pear fodder— were characterized. The conceptual technical analysis was determined through quantitative and qualitative indicators, based on mathematical expressions and equations. Results: Quantitative indicators showed a fermentation technology with limited efficiency, which provides an opportunity for technical improvements. Findings/Conclusions: The application of fermentation technology results in significant savings in water, soil, and fertilizer resources. Furthermore, it provides an alternative for fodder production and food security for livestock in the semi-arid region of Mexico. [ABSTRACT FROM AUTHOR]

Background and Aim: Metallo-beta-lactamases (MBLs) which open β-lactam ring with help of metal cofactor degrade all the classes of β-lactams except monobactams and are notable for their constant and efficient carbapenemase activity. New Delhi Metallo-beta-lactamase (NDM) is type of carbapenemase which is able to inactivate all β-lactams except aztreonam. Combined disk synergy test (CDST) and polymerase chain reaction (PCR) analysis are used for the detection of MBL production. Materials and Methods: All clinical specimens received in the microbiology department for culture and sensitivity from indoor patients were included in study. Brief history and related data of the patients was being recorded. The direct Gram staining and samples were inoculated on culture media and incubated at 37°C for 18-24 h. Biochemical reactions were performed and the antibiotic susceptibility test was performed by Kirby-Bauer Disk-Diffusion method and VITEK 2. All the multidrug-resistant (MDR) Gram-negative bacteria (GNB) which were carbapenem resistant subjected to CDST and Genotypic detection of NDM-1 by PCR was done. The association between categorical variables was explored using the Pearson's Chi-square test. Results: The present study was conducted on 260 GNB isolated from 5307 specimens, 164 were MDR, 68 were carbapenem resistant, and 48 were found to be MBLs (19 were fermenters; 29 were nonfermenters). Thirty-six blaNDM-1 gene was isolated from both MDR fermenters and nonfermenters. The positivity of CDST in detecting blaNDM-1 positive MBLs taking PCR as the gold standard was 75%. Conclusion: NDM-1 carrying isolates disseminate quickly even among the organisms of different genera, their presence in high proportion could further threaten the public health and put an end to our current pharmacopoeia. [ABSTRACT FROM AUTHOR]

Copyright of Revista del Centro de Investigación. Universidad La Salle is the property of Universidad La Salle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effect of a concentrated mixture of denitrifying and fermenting bacteria on the composition, structure, state, and properties of alluvial clay soils sampled in Perm City has been studied. The results demonstrate an increase in the volume of a sample when soaked in a solution of microorganisms, changes in the mineral composition of soils, an increase in their porosity and humidity, a decrease in the density and stress-strain characteristics. The processes of interaction between microorganisms and the components of soils are mentioned, which can lead to such effects. [ABSTRACT FROM AUTHOR]

This study was undertaken to investigate the relationship between chemical composition and microbial profile of rumen liquid-associated bacteria ( LAB) in vivo ( Murciano- Granadina goats) and in a rumen simulation system (single-flow continuous-culture fermenters). To achieve this aim, analyses of purine bases along with some molecular techniques (quantitative PCR to assess abundance and DGGE to identify biodiversity and bacterial profile) were carried out. A control diet ( AHC) based on alfalfa hay ( AH) and concentrate ( C) in a 1:1 ratio and two experimental diets ( AHCBI and AHCBII), in which concentrate was partially replaced with multinutrient blocks, were used. Diets AHCBI and AHCBII included multinutrient blocks differing in the relative amount of two-stage olive cake and the source of protein (sunflower meal vs. fava beans). We aimed to investigate the effect of these blocks on rumen microbiota to evaluate their potential as safe substitutes of cereal-based concentrates. Similar patterns of response to diet were found for chemical composition, microbial abundances and diversity in LAB isolated from goat's rumen and fermenters. Whereas bacterial density (log10 gene copies/g FM: 11.6 and 9.4 for bacteria and methanogens, respectively, in rumen) and diversity indexes ( Shannon index: 3.6) were not affected by diet, DGGE analyses showed that bacterial community profile was affected. The cluster analysis suggested differences in bacterial profile between LAB pellets isolated from the rumen of goat and fermenters. A relationship between chemical composition and bacterial community composition in LAB pellets seems to exist. Changes in the former were reflected in the bacterial community profile. Further research is needed to clarify the relationship between chemical and microbial composition of ruminal bacterial pellets with diets of different quality. [ABSTRACT FROM AUTHOR]

Previous studies have shown that adding fish oil ( FO) to ruminant animal diets increased vaccenic acid ( VA; t11 C18:1) accumulation in the rumen. Therefore, the objective of this study was to evaluate the effect of dietary FO amounts on selected strains of rumen bacteria involved in biohydrogenation. A single-flow continuous culture system consisting of four fermenters was used in a 4 × 4 Latin square design with four 9 days consecutive periods. Treatment diets were as follows: (i) control diet (53:47 forage to concentrate; CON), (ii) control plus FO at 0.5% ( DM basis; FOL), (iii) control plus FO at 2% ( DM basis; FOM) and (iv) control plus FO at 3.5% ( DM basis; FOH). Fermenters were fed treatment diets three times daily at 120 g/day. Samples were collected from each fermenter on day 9 of each period at 1.5, 3 and 6 h post-morning feeding and then composited into one sample per fermenter. Increasing dietary FO amounts resulted in a linear decrease in acetate and isobutyrate concentrations and a linear decrease in acetate-to-propionate ratio. Propionate, butyrate, valerate and isovalerate concentrations were not affected by FO supplementation. Concentrations of C18:0 in fermenters linearly decreased, while concentrations of t10 C18:1 and VA linearly increased as dietary FO amounts increased. The concentrations of c9 t11 and t10 c12 conjugated linoleic acid were not affected by FO supplementation. The DNA abundance for Butyrivibrio fibrisolvens, Butyrivibrio vaccenic acid subgroup, Butyrivibrio stearic acid subgroup and Butyrivibrio proteoclasticus linearly decreased as dietary FO amounts increased. In conclusion, FO effects on trans fatty acid accumulation in the rumen may be explained in part by FO influence on Butyrivibrio group. [ABSTRACT FROM AUTHOR]

Progress during the past 25 years regarding our knowledge of brewer's yeast strains is considered. This is not a comprehensive review but rather focuses on some specific areas. These areas include a brief description of genomics, proteomics and metabolomics as applied to brewer's yeast strains. This review subsequently considers differences between ale and lager yeast strains, the uptake and metabolism of wort sugars and amino acids, yeast flocculation, yeast management between fermentations and yeast strain genetic stability. The question of process intensification, with particular attention to high-gravity brewing, is also addressed. Fermentation systems and processes are considered with an emphasis on novel procedures for stirred fermentations. Copyright © 2013 The Institute of Brewing & Distilling [ABSTRACT FROM AUTHOR]

This study demonstrated the utility in correlating performance and community structure of a trichloroethene (TCE)-dechlorinating microbial consortium; specifically dechlorinators, fermenters, homoacetogens, and methanogens. Two complementary approaches were applied: predicting trends in the microbial community structure based on an electron balance analysis and experimentally assessing the community structure via pyrosequencing and quantitative polymerase chain reaction (qPCR). Fill-and-draw reactors inoculated with the DehaloR⁁2 consortium were operated at five TCE-pulsing rates between 14 and 168 µmol/10-day-SRT, amended with TCE every 2 days to give peak concentrations between 0.047 and 0.56 mM (6-74 ppm) and supplied lactate and methanol as sources of e- donor and carbon. The complementary approaches demonstrated the same trends: increasing abundance of Dehalococcoides and Geobacter and decreasing abundance of Firmicutes with increasing TCE pulsing rate, except for the highest pulsing rate. Based on qPCR, the abundance of Geobacter and Dehalococcoides decreased for the highest TCE pulsing rate, and pyrosequencing showed this same trend for the latter. This deviation suggested decoupling of Dehalococcoides growth from dechlorination. At pseudo steady-state, methanogenesis was minimal for all TCE pulsing rates. Pyrosequencing and qPCR showed suppression of the homoacetogenic genera Acetobacterium at the two highest pulsing rates, and it was corroborated by a decreased production of acetate from lactate fermentation and increased propionate production. Suppression of Acetobacterium, which can provide growth factors to Dehalococcoides, may have contributed to the decoupling for the highest TCE-pulsing rate. Biotechnol. Bioeng. 2012;109: 2230-2239. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia y Tecnología (1390-4051) is the property of Universidad Tecnica Estatal de Quevedo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microbially reduced iron minerals can reductively transform a variety of contaminants including heavy metals, radionuclides, chlorinated aliphatics, and nitroaromatics. A number of Cellulomonas spp. strains, including strain ES6, isolated from aquifer samples obtained at the U.S. Department of Energy's Hanford site in Washington, have been shown to be capable of reducing Cr(VI), TNT, natural organic matter, and soluble ferric iron [Fe(III)]. This research investigated the ability of Cellulomonas sp. strain ES6 to reduce solid phase and dissolved Fe(III) utilizing different carbon sources and various electron shuttling compounds. Results suggest that Fe(III) reduction by and growth of strain ES6 was dependent upon the type of electron donor, the form of iron present, and the presence of synthetic or natural organic matter, such as anthraquinone-2,6-disulfonate (AQDS) or humic substances. This research suggests that Cellulomonas sp. strain ES6 could play a significant role in metal reduction in the Hanford subsurface and that the choice of carbon source and organic matter addition can allow for independent control of growth and iron reduction activity. [ABSTRACT FROM AUTHOR]

There is considerable interest in exploiting the novel physical and biological properties of microbial exopolysaccharides in industry and medicine. For economic and scientific reasons, large scale production under carefully monitored and controlled conditions is required. Producing exopolysaccharides in industrial fermenters poses several complex bioengineering and microbiological challenges relating primarily to the very high viscosities of such culture media, which are often exacerbated by the producing organism''s morphology. What these problems are, and the strategies for dealing with them are discussed critically in this review, using pullulan, curdlan, xanthan, and fungal ββ-glucans as examples of industrially produced microbial exopolysaccharides. The role of fermenter configuration in their production is also examined. [ABSTRACT FROM AUTHOR]

single flow continuous culture fermenter system was used in this study to investigate the influence of dietary lipid supplements varying in their fatty acid content on the DNA concentration of selected rumen bacteria. Four continuous culture fermenters were used in a 4×4 Latin square design with four periods of 10 d each. Treatment diets were fed at 45 g/d (DM basis) in three equal portions during the day. The diets were: 1) control (CON), 2) control with animal fat source (SAT), 3) control with soybean oil (SBO), and 4) control with fish oil (FO). Lipid supplements were added at 3% of diet DM. The concentrations of total volatile fatty acids and acetate were not affected ( P>0.05) by lipid supplements. Concentrations of propionate, iso-butyrate, valerate and iso-valerate were highest ( P<0.05) with the FO diet compared with the other treatment diets. The concentration of til C18:l (vaccenic acid, VA) in effluents increased ( P<0.05) with SBO and FO diets and was highest with the SBO diet. The concentrations of C18:0 in effluents were lowest ( P<0.05) for the FO diet compared with the other treatment diets. Concentrations of DNA for Anaerovibrio lipolytica, and Butyrivibrio proteoclasticus in fermenters were similar ( P>0.05) for all diets. The DNA concentrations of Butyrivibrio fibrisolvens and Ruminococcus albus in fermenters were lowest ( P<0.05) with the FO diet but were similar ( P>0.05) among the other treatment diets. Selenomonas ruminantium DNA concentration in fermenters was highest ( P<0.05) with the FO diet. In conclusion, SBO had no effect on bacterial DNA concentrations tested in this study and the VA accumulation in the rumen observed on the FO diet may be due in part to FO influence on B. fibrisolvens, R. albus, and S. ruminantium. [ABSTRACT FROM AUTHOR]

We investigated the influence of inhibitors of energy metabolism and ionophores on the growth and formation of metabolic products in alkaliphilic anaerobes characterized by various catabolism types. It was shown that blockage of oxidative phosphorylation by the addition of N,N′-dicyclohexylcarbodiimide (DCCD), an inhibitor of F1F0 ATP synthase, resulted in a complete arrest of the growth of the acetogenic bacterium Tindalliamagadiensis with arginine as an electron acceptor. In the presence of pyruvate, substrate-level phosphorylation occurred. The methylotrophic methanogenic archaebacterium Methanosalsuszhilinae did not grow with DCCD and vanadate, an inhibitor of Е1Е2 ATPase, suggesting the presence of two ATPase types in this species. In the saccharolytic alkaliphiles Halonatronum saccharophilum, Amphibacillus tropicus, and Spirochaeta alkalica (which are characterized by different pH optima), the contribution of the H+ gradient to the energy metabolism and, presumably, to the maintenance of the intracellular pH level decreased with an increase in the degree of alkaliphily. Based on the data of an inhibitor assay using protonophores, monensin, and amiloride, we suggest that all of the bacteria tested depend on H+ and Na+ gradients. The Na+/H+ antiport appears to be a universal mechanism of regulating the intracellular pH level and the interaction between the Na+ and H+ cycles in bacterial cells cultivated under alkaline conditions. [ABSTRACT FROM AUTHOR]