*6.1. Cell Disruption*

A major practical problem in using such microalgae as *Murielopsis* sp. or *S. almeriensis* is the need for cell wall disruption. This can be accomplished through a variety of ways, e.g., milling, ultrasound, microwave, freezing, thawing or chemical attack [45]. 

The mortar-and-pestle procedure described by Mínguez-Mosquera *et al*. [73] provides full recovery, but it cannot be scaled up to industrial practice; sonication and ball milling produce results similar to that procedure, as long as alumina is employed as disaggregating agent [45]. Ceron *et al*. [74] complemented the aluminabased cell disruption with alkaline treatment using 4% (w/v) aqueous KOH (40 °C); disaggregation and lipid expression were both facilitated. 
