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121.
122.
M. Y. Shukor M. F. Rahman Z. Suhaili N. A. Shamaan M. A. Syed 《World journal of microbiology & biotechnology》2009,25(7):1225-1234
A bacterium that was able to tolerate and reduce as high as 50 mM of sodium molybdate to molybdenum blue has been isolated
from a metal recycling ground. The isolate was tentatively identified as Serratia sp. strain Dr.Y8 based on the carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny.
ANOVA analysis showed that isolate Dr.Y8 produced significantly higher (P < 0.05) amount of Mo-blue with 3, 5.1 and 11.3 times more molybdenum blue than previously isolated molybdenum reducers such
as Serratia
marcescens strain Dr.Y6, E. coli K12 and E. cloacae strain 48, respectively. Its molybdate reduction characteristics were studied in this work. Electron donor sources such as
sucrose, mannitol, fructose, glucose and starch supported molybdate reduction. The optimum phosphate, pH and temperature that
supported molybdate reduction were 5 mM, pH 6.0 and 37°C, respectively. The molybdenum blue produced from cellular reduction
exhibited a unique absorption spectrum with a maximum peak at 865 nm and a shoulder at 700 nm. Metal ions such as chromium,
silver, copper and mercury resulted in approximately 61, 57, 80, and 69% inhibition of the molybdenum-reducing activity at
1 mM, respectively. The reduction characteristics of strain Dr.Y8 suggest that it would be useful in future molybdenum bioremediation. 相似文献
123.
T. A. Misharina M. B. Terenina N. I. Krikunova I. A. Khankhalaeva I. S. Khamagaeva L. L. Nikiforova 《Applied Biochemistry and Microbiology》2008,44(5):545-550
The differences between the composition of volatile substances in two specimens of dry smoked sausages produced using a standard and experimental (a mixture of propionic acid bacteria and bifidobacteria) cultures were studied by capillary gas chromatography. It was found that the experimental starter culture intensified the flavor-formation processes as compared with the standard culture. The experimental specimen had richer qualitative and quantitative compositions and displayed more intensive aroma and flavor. The contents of lactones and volatile terpenoids in the experimental specimen were much higher than in the control. The organoleptic characteristics of experimental dry smoked sausage specimen were considerably better. 相似文献
124.
125.
126.
A. D. Neklyudov A. N. Ivankin A. V. Berdutina 《Applied Biochemistry and Microbiology》2000,36(5):452-459
Properties of protein hydrolysates and possible uses of these substances in research and various branches of industry are
considered. The main problem discussed in this paper is the relationship between the degree of protein conversion and characteristics
(structural-functional and physicochemical) of hydrolysates. 相似文献
127.
R. L. Orozco M. D. Redwood P. Yong I. Caldelari F. Sargent L. E. Macaskie 《Biotechnology letters》2010,32(12):1837-1845
Escherichia coli strains MC4100 (parent) and a mutant strain derived from this (IC007) were evaluated for their ability to produce H2 and organic acids (OAs) via fermentation. Following growth, each strain was coated with Pd(0) via bioreduction of Pd(II).
Dried, sintered Pd-biomaterials (‘Bio-Pd’) were tested as anodes in a proton exchange membrane (PEM) fuel cell for their ability
to generate electricity from H2. Both strains produced hydrogen and OAs but ‘palladised’ cells of strain IC007 (Bio-PdIC007) produced ~threefold more power as compared to Bio-PdMC4100 (56 and 18 mW respectively). The power output used, for comparison, commercial Pd(0) powder and Bio-Pd made from Desulfovibrio desulfuricans, was ~100 mW. The implications of these findings for an integrated energy generating process are discussed. 相似文献
128.
I. Rosario G. Soro S. Déniz O. Ferrer F. Acosta D. Padilla B. Acosta 《Mycopathologia》2010,169(4):315-319
Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts
in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of
Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this
disease. 相似文献
129.
130.
M Feneant-Thibault N Moatti J Maccario A Corriat A Lemonnier 《Biochemical and biophysical research communications》1987,142(1):221-227
Proline uptake was studied in human skin fibroblasts by simultaneous running of kinetic and inhibition experiments on the same cell lines. Two systems for proline uptake were shown: a high-affinity system not inhibited by alpha-(methylamino)isobutyric acid and a low affinity system inhibited by this amino acid (i.e. system A). These results appear to be of interest, firstly because up till now, system A was considered preferable for proline uptake in human fibroblasts, and secondly because they illustrate the need for combined inhibition and kinetic studies of amino acid uptake, especially when the substrate concentration range used and the respective Km of the systems do not allow their detection by kinetic analysis alone. Furthermore, this high-affinity system may have major physiological implications. 相似文献