IMMOBILIZATION OF P. PUTIDA A (ATCC 12633) CELLS USING CA-ALGINATE: ENVIRONMENTAL APPLICATIONS FOR THE REMOVAL OF CATIONIC SURFACTANTS POLLUTANTS IN INDUSTRIAL WASTEWATER

LUCCHESI G.I.; BERGERO M F; BOERIS P.S.; LOPÉZ G.A; HEREDIA R.M; LIFFOURRENA, A.S.

Alginic Acid: Chemical Structure, Uses and Health Benefits

Nova publishers

Año: 2015; p. 105 - 117

One of the most promising areas of environmental research is using the immobilized cells to reduce environmental pollutions through biodegradation of many toxic compounds. Cross-linked Ca-alginate is one of the most commonly used immobilization polymers due to its highly porous structure that facilitate diffusion of solutes and dissolved gases. Quaternary ammonium based-surfactants (QACs) are commercial chemicals widely used as disinfectant and routinely deposited on land and into water systems, as either part of an intended process or as industrial and household waste. Upon release into the environment, the biodegradability of QACs is limited by their antimicrobial activity and for this reason, the effective degradation of QACs is necessary to protect the environment. Pseudomonas putida A (ATCC 12633) is a ubiquitous gram-negative bacterium and a potent pollutant degrader that utilized QACs as a carbon, nitrogen and energy source. This ability has great application for the bioremediation of contaminated sites and biotransformation of industrial wastes. As immobilized microorganism offer several advantages over free cells for the bioremediation of contaminated sites, the present work has been carried out to develop an immobilized bacterial cell system for the degradation of QACs. Accordingly, the performance of the degradation of QACs: tetradecyltrimethylammonium bromide, tetradecylbenzyldimethylammonium chloride, hexadecylbenzyldimethylammonium chloride and benzalkonium chloride by Ca-alginate-immobilized cells of P. putida A (ATCC 12633) was compared with that of its free form counterpart. The results revealed that the immobilized cell systems can more efficiently degrade than free cells. Maximun degradation was observed with P. putida A (ATCC 12633) cells immobilized in 4 % (v/v) Ca-alginate concentration with a bead size of 3.0 mm containing 1-5 x 108 cfu ml-1 of cells, at 30 °C, in buffered medium (pH 7.5), under agitation (100 rpm). The developed system was highly stable and the Ca-alginate entrapped P. putida cells can be recycled up to the four cycles without any marked change in their ability to carry out the QACs degradation. QACs of an industrial effluent were successfully removed more than 90% in 48 h by immobilized cells of P. putida A (ATCC 12633). The reduction in the QACs concentration after treatment with immobilized cells can be correlated with the reduction in the phytotoxicity on Lactuta sativa seed germination and root elongation. We conclude that the Ca-alginate entrapped P. putida A (ATCC 12633) cells can be successfully applied for the remediation of QACs present in industrial wastewater systems.