Microbial Cellulose as Support Material for the Immobilization of Denitrifying Bacteria

Abstract

The purpose of this study was to investigate the immobilization of denitrifying bacteria on microbial cellulose (MC) for biological denitrification. A novel denitrifying bacterium, Pseudomonas stutzeri, was immobilized in microbial cellulose and introduced into an up flow packed bed reactor in order to remove nitrate from synthetic influent. The MC presented the high biomass concentration throughout the experiment, achieving 3.4 mg biomass/g support. The efficiency of the system for denitrification was tested under different running conditions. Complete biological denitrification of the synthetic effluent was achieved at low hydraulic residence times, less than 4 h, and high nitrate concentration (200 mg NO 3 -N/L). The immobilization of the bacterium in MC increased the adsorption capacity, decreased the cell leakage from the beads, resulted in higher activity of the immobilized cells, and allowed better operational control.

Preliminary testing and design of permeable bioreactive barrier for phenanthrene degradation by Pseudomonas stutzeriCECT 930 immobilized in hydrogel matrices

“…The higher kinetics constant for the immobilized systems demonstrated that the entrapment in hydrogel matrices increased the degradation ability of this microorganism. These results were in agreement with those reported by Rezaee et al They determine that the immobilization of P. stutzeri in Ca‐alginate increased the stability of a microbial system for denitrification of effluents, allowing its application under extreme environmental conditions.…”

Ethanol production from concentrated food waste hydrolysates with yeast cells immobilized on corn stalk

“…3c), an uneven surface was seen, which indicated that the surface of the individual fibers had been changed drastically. Such kind of rupture of cell wall surface or a visible increase of porosity was believed to increase the specific surface area of the carriers, which contributed to the absorption of cells (Rezaee et al 2008). During the hydrolysis, it was observed that the porous corn stalk cells which could embed the yeast cells were disrupted greatly after 6 h (Fig.…”

Comparative evaluation of bacterial cellulose (nata) as a cryoprotectant and carrier support during the freeze drying process of probiotic lactic acid bacteria

“…The cellulose is highly crystalline, has high water absorption capacity and mechanical strength in the wet state, ultra fine network structure (Astley, Chanliaud, & Donald, 2001). Taking advantage of these properties researchers have tried to immobilize various bacteria on microbial cellulose (Rezaee, Godini, & Bakhtou, 2008) and tried to use it to carry out alcoholic fermentations (Iconomopoulou, Kanellaki, Psarianos, & Koutinas, 2000) and industrial waste water treatments (Rezaee, Godini, Naimi, & Masombaigi, 2008).…”