A process for the isolation and purification of HMG-CoA reductase
inhibitors from a mycelium biomass is described, which process comprises:
clarifying a mycelium broth and concentrating the clarified broth to a
lower volume, acidifying of the concentrate to a pH value in the range of
4.5 to 7.5, followed by extracting the HMG-CoA reductase inhibitor with
ethyl acetate, crystallization of the HMG-CoA reductase inhibitor from a
water-miscible or water-soluble organic solvent, and crystallization of
the HMG-CoA reductase inhibitor from an organic solvent having limited
miscibility or solubility with water. The crystallization steps may also
be reverse. The concept of a combination of the specified crystallization
steps can also be used for the purification of a crude HMG-CoA reductase
inhibitor.
