Preparation of a multifunctional bacterial fertilizer by living azospirillum simplex cells immobilized on poly(sodium acrylate)

摘要

A living azospirillum simplex cell (LASSC) was immobilized on poly(sodium acrylate) (PSA). The method of preparation of the immobilized-cell (LASSC-PSA) was studied. LASSC was immobilized on PSA in an immobilizing medium of Na{sub}2HPO{sub}4·12H{sub}2O-NaH{sub}2PO{sub}4·2H{sub}2O (pH 7.0) buffer, sterile water, a solution of NaCl (0.85% m/m), cultured medium (pH 7.0), respectively. The desorption capacity of LASSC on LASSC-PSA in sterile water was measured and when the Na{sub}2HPO{sub}4·12H{sub}2O-NaH{sub}2PO{sub}4·2H{sub}2O (pH 7.0) buffer served as the immobilizing medium, the desorption capacity of LASSC on LASSC-PSA was the highest. The rate (m/m) of PSA and LASSC (wet weight) also affected considerably the desorption capacity of LASSC on LASSC-PSA in sterile water, and the best rate was 1:0.5. The desorption capacity of LASSC on LASSC-PSA was 50% of that at the beginning and that was still 10{sup}9 cfu/g on storage for 5 months when the rate (m/m) of PSA and LASSC (wet weight) was 1:0.5, using Na{sub}2HPO{sub}4·12H{sub}2O-NaH{sub}2PO{sub}4·2H{sub}2O (pH 7.0) buffer as immobilizing medium.