Can anyone help with a colleague's problem? He is trying to purify an
extracellular lipase produced by a fungus in aqueous media containing high
concentrations of peptone and olive oil. It appears that part of the lipase
is bound to the oil phase. When he tries to precipitate the enzyme with
ammonium sulphate, at concentrations of salt below 70% he recovers < 40% of
the activity. However, at high concentration, 80-85% salt, he gets no better
yield, as some of the protein stays in the upper phase with the oil, and does
not enter the pellet. He has tried removing the oil with immiscible solvents,
but this is to harsh, and lowers the enzyme activity.
Can anyone suggest an approach to this problem? Thank you in advance for your
time in this.
