2. Chemical and Enzymatic Methods

A. Alkali Treatment- This is a harsh but effective chemical treatment to lyse the cells. Alkali treatment causes lipid saponification which disturbs the lipid packing and affects the cell wall integrity.

B. Detergent: Addition a detergent solution to the cell causes solubilization of lipid to form micelle. The effect of detergent on cell wall increases linearly with concentration. The detergent concentration which causes abrupt change in lipid solubility and forms micelle is known as critical micelle concentration (CMC). Example of detergents are SDS, CTAB, Triton X-100, saponin, digitonin.

Figure 28.4: Effect of detergent on plasma membrane integrity. (A) Solubilization (B) Permeabilization

C. Permeabilization: A partial cell wall disruption or permeabilization is achieved by organic solvent such as toluene (Figure 28.4). The organic solvent is absorbed by the cell wall resulting in its swelling and ultimate rupture. But at low concentration, organic solvent permeablizes the cell wall without disturbing cellular integrity. This process allow to use cell as a reaction vessel to catalyze a reaction and get desired product.