Is there any changes is inclusion bodies/gas vacuoles? Is this system useful for Sole Hydrocarbon production? or Is some cheaper way of harvesting of B. braunii?
Probably that temperature induces cell death and when these algae die aggregate and precipitate. 4 ° C sounds pretty low, suitable for psychrophiles and psychrotolerant microorganism.
Respect to a way to harvesting probably yes, but don´t is cheaper... Imagine cooling costs for long periods huge amounts of liquid cultures .