Optimization of immobilization conditions by conventional and statistical strategies for alkaline lipase production by Pseudomonas aeruginosa mutant cells: scale-up at bench-scale bioreactor level

Authors : Deepali BISHT, Santosh Kumar YADAV, Nandan Singh DARMWAL

Pages : 392-404

Doi:10.3906/biy-1209-19

View : 10 | Download : 5

Publication Date : 2013-12-01

Article Type : Research Paper

Abstract :Suitability of 3 matrices, agarose, sodium alginate, and polyacrylamide, for immobilization of mutant cells of Pseudomonas aeruginosa MTCC 10,055 was investigated. Of these, agarose was proven to be the best as exhibiting maximum enzyme production insert ignore into journalissuearticles values(4363.4 U/mL);, followed by polyacrylamide gel insert ignore into journalissuearticles values(2172.3 U/mL);. Alginate beads were the poorest. The one-variable-at-a-time approach suggested agarose at 2.0%, immobilized bead at 4.0 g blocks/50 mL, and initial cell loading of 0.8 g in the matrix as optimum conditions for maximum lipase production insert ignore into journalissuearticles values(5982.3 U/mL); after 24 h of incubation. However, response surface methodology studies determined the optimum values of these variables as 1.96%, 4.06 g blocks/50 mL, and 0.81 g of cells in the matrix for maximum lipase production insert ignore into journalissuearticles values(6354.23 U/mL); within 22.54 h of incubation. The agarose blocks were reusable for 7 cycles without any significant loss in lipase yield. Bench-scale bioreactor level optimization resulted in further enhancement in lipase yield insert ignore into journalissuearticles values(6815.3 U/mL); at 0.6 vvm aeration and 100 rpm agitation within only 20 h of incubation. Presumably, this is the first attempt for lipase production by immobilized cells of P. aeruginosa at the bioreactor level. The agarose-immobilized mutant cells showed potential candidature for alkaline lipase production at the industrial level.
Keywords : Key words Alkaline lipase, bench scale bioreactor, immobilized cells, response surface methodology