Monoculture causes nutrient losses and leads to declines in soil fertility and biomass production over successive cultivation. The rhizosphere, a zone of usually high microbial activities and clearly distinct from bulk soil, is defined as the volume of soil around living roots and influenced by root activities. Here we investigated enzyme activities and microbial biomass in the rhizosphere unde...

BACKGROUND Members of the bacterial genus Caldicellulosiruptor are the most thermophilic cellulolytic organisms described to date, and have the ability to grow on lignocellulosic biomass without conventional pretreatment. Different species vary in their abilities to degrade cellulose, and the presence of CelA, a bifunctional glycoside hydrolase that contains a Family 48 and a Family 9 catalytic...

This study investigated the effect, on reactor performance and biomass retention inside the bed, of the material used to make the supports of anaerobic fixed-bed reactors. Three inert supports of similar shape but made of three different materials polyvinyl chloride, polypropylene, high-density polyethylene were manufactured and used. All three supports had the same specific surface area but di...

The main aim of this study was to evaluate the performance of a modified sequencing batch reactor (MSBR) using fixed Kaldnes carriers fed with acclimated sludge for ammonium removal via simultaneous nitrification-denitrification (SND) in synthetic wastewater. The results exhibited a SND of 82.3% within a 450-minute cycle time which was higher than that of a SBR without carrier (69.83%). Nitrite...

Biomass, production and heterotrophic activity of bacterioplankton were determined for two weeks in the Great Astrolabe Reef lagoon, Fiji. Bacterial and Bacterial activities were distributed homogeneously throughout the water column (20 to 40m deep) and varied little from site to site inside the lagoon. Bacterioplankton biomass and production also varied little over a diel period with coefficie...

Bioconversion of cellulose-containing substrate to glucose represents an important area of modern biotechnology. Enzymes for the degradation of the polysaccharide part of biomass have been produced, mostly by fungi belonging to genus Trichoderma. Studies were carried out with the mutant strain Trichoderma reesei-M7, a cellulase producer. Spores of the enzyme producer were irradiated with differ...

A biofiltration system inoculated with the mold Paecilomyces variotii CBS115145 showed a toluene elimination capacity (EC) of around 250 g/m3 of biofilter/h, which was higher than the values usually reported for bacteria. P. variotii assimilated m- and p-cresols but not the o isomer. Initial toluene hydroxylation occurred both on the methyl group and through the p-cresol pathway. These results ...

BACKGROUND The E. coli lac operon and its components have been studied for decades, and lac-derived systems are widely used for recombinant protein production. However, lac operon dynamics and induction behavior remain the paradigm of gene regulation. Recently, an HPLC-MS-based method to quantify IPTG in the medium and inside the biomass has been established, and this tool may be useful to unco...

In the field of biomass and bio-energy production, an analysis was performed of the whole production process from biomass supply to bio-energy production. The available biomass, harvesting and transportation costs and the distribution of supply area were quantified. The assessment of volumes was based on forest type and its relative increment. The transportation costs, influenced by different s...

The growth rate and biomass yield efficiency of anaerobic ammonium oxidation (anammox) bacteria are markedly lower than those of most other autotrophic bacteria. Among the anammox bacterial genera, the growth rate and biomass yield of the marine anammox bacterium "Candidatus Scalindua sp." is still lower than those of other anammox bacteria enriched from freshwater environments. The activity an...