Crude enzyme produced via solid state fermentation using the fungal strain Aspergillus oryzae was used to lyse cells of Cupriavidus necator, enabling the recovery of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), P(3HB-co-12mol% 3HV). A central composite design was employed in order to optimize the temperature and the pH value leading to the highest lysis of Cupriavidus necator cells (88.9 ± 0.4%) and the optimal hydrolysis of protein contained in bacterial cells. Enzymatic lysis of bacterial cells was also carried out at the optimum temperature and uncontrolled pH value leading to P(3HB-co-12mol% 3HV) recovery yield and purity of 98% and 96.7%, respectively