to study the effect of salinity on physiological and morphological traits of chickpea in 2010 at faculty of agriculture and natural resources, university of tehran with seven chickpea genotypes. two experiments design was rcbd with 3 replications and 5 levels of salinity stress (ctrl, 200, 150, 100, 50 mm) for laboratory experiment on germination indices and greenhouse experiment on physiologic...

abstract soil microbial activity and biochemical processes are often limited by carbon availability in arid- and semi-arid regions, probably due to the low organic matter content. consequently, return of plant residues to soil is a convenient and effortless practice for increasing microbial activities and biochemical reactions. the primary objective of this study was to evaluate the effect of v...

The aim of this paper is to study the microbial and structural changes occurring during the transition from flocculent (used as inoculum) to biofilm and granular sludge in a Sequencing Batch Biofilter Granular Reactor (SBBGR). SBBGR is a new and promising technology characterised by low sludge production (5-6 times lower than in conventional treatment plants), high biomass concentration (up to ...

BACKGROUND New lignocellulolytic enzymes are needed that maintain optimal activity under the harsh conditions present during industrial enzymatic deconstruction of biomass, including high temperatures, the absence of free water, and the presence of inhibitors from the biomass. Enriching lignocellulolytic microbial communities under these conditions provides a source of microorganisms that may y...

Palmitic acid was the main long chain fatty acids (LCFA) that accumulated onto the anaerobic sludge when oleic acid was fed to an EGSB reactor. The conversion between oleic and palmitic acid was linked to the biological activity. When palmitic acid was fed to an EGSB reactor it represented also the main LCFA that accumulated onto the sludge. The way of palmitic acid accumulation was different i...

BACKGROUND The conversion of plant biomass to ethanol via enzymatic cellulose hydrolysis offers a potentially sustainable route to biofuel production. However, the inhibition of enzymatic activity in pretreated biomass by lignin severely limits the efficiency of this process. RESULTS By performing atomic-detail molecular dynamics simulation of a biomass model containing cellulose, lignin, and...

A new method combining automatic turbidimetry and sequential viable count determinations was developed to evaluate the in vitro activity of various antifungal agents alone and in combination against three clinical isolates of Candida spp. (two Candida albicans and one C. tropicalis) at two inocula (10(-5) and 10(-6) CFU/ml). Specific parameters were derived from the time-kill curves: the maxima...

Specific ATP content of volatile solids was measured to characterize the sludge activity in a sequential an-aerobic/aerobic wastewater treatment system, with an upflow anaerobic sludge blanket (UASB) reactor and a three-phase aerobic fluidized bed (AFB) reactor. The wastewater COD level was 2000-3000 mg/L in simulation of real textile waste-water. The ATP content and the specific ATP contents o...

Understanding the interactions between cellulases and cellulosic substrates is critical to the development of an efficient artificial cellulase system for conversion of biomass to sugars. We directed specific mutations to the interactive surface of the Acidothermus cellulolyticus EI endoglucanase catalytic domain. The cellulose-binding domain is not translated in these mutants. Amino acid mutat...

The fluorescence of a fermentation culture was studied for its application as an estimator of biomass concentration. The measurement was obtained by irradiating the culture with ultraviolet light (366 nm) through a glass window and detecting fluorescent light at the window surface at 460 nm. It was estimated that over one-half of the fluorescent material was intercellular reduced nicotinamide a...