Immobilization of nitrite oxidizing bacteria using biopolymeric chitosan media

• Published in: Journal of environmental sciences (China) 2013-02, Vol.25 (2), p.262-267
• Main Authors: Lertsutthiwong, Pranee, Boonpuak, Duangcheewan, Pungrasmi, Wiboonluk, Powtongsook, Sorawit
• Format: Article
• Language: English
• Subjects: Bacteria - metabolism; Chitosan; Hydrogen-Ion Concentration; immobilization; Molecular Weight; nitrite-oxidizing bacteria; nitrites; Nitrites - metabolism; nitrogen-fixing bacteria; particle size; pH adjustment; scanning electron microscopes; wastewater aquaculture; 固定化; 固定时间; 壳聚糖; 媒体; 生物聚合; 硝化细菌; 脱乙酰壳多糖; 脱乙酰度
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/S1001-0742(12)60059-X

The effects of chitosan characteristics including the degree of deacetylation, molecular weight, particle size, pH pretreatment and immobilization time on the immobilization of nitrite-oxidizing bacteria (NOB) on biopolymeric chitosan were investigated. Nitrite removal efficiency of immobilized NOB depended on the degree of deacetylation, particle size, pH pretreatment on the surface of chitosan and immobilization time. Scanning electron microscope characterization illustrated that the number of NOB cells attached to the surface of chitosan increased with an increment of immobilization time. The optimal condition for NOB immobilization on chitosan was achieved during a 24-hr immobilization period using chitosan with the degree of deacetylation larger than 80% and various particle size ranges between 1–5 mm at pH 6.5. In general, the NOB immobilized on chitosan flakes has a high potential to remove excess nitrite from wastewater and aquaculture systems.