A comparative study on cell disruption methods for release of aspartase from E. coli K-12.

Applicability of different mechanical cell disruption techniques namely sonication, bead milling and French press for the release of aspartase from E. coli K-12 was compared. Various operating parameters of each technique were optimized to obtain maximum aspartase release. The efficiency of aspartase release and cell disruption by all the methods was also compared under optimal conditions. The maximum release of aspartase (98.22%) and maximum cell breakage (84.25%) was observed using French press, while 92% of aspartase release was obtained by both sonication and bead milling. The order of cell disruption constant (k) for aspartase release by these methods was French press > bead milling > sonication. Disruption of cells using French press also demonstrated maximum protein release (14.12 mg/mL). The crude enzyme preparations can be further used for purification and its applications.