Two cell disruption methods, mechanical and chemical, were applied for the recovery of a fusion protein named CIGB 550-E7, expressed on Escherichia coli grown in defined saline media. A comparison of the methods was done, and various operating parameters for each technique were optimized to obtain the maximum disruption efficiency and CIGB 550-E7 protein release. The mechanical disruption’s yield and recovery were 1.24 and 1.37 times higher than those obtained with chemical disruption. Modified conditions were assayed for the CIGB 550-E7 obtained by chemically defined media using the mechanical and chemical cell disruption methods.