Screening of Lipase-producing Strain for Catalytic Synthesis of Ester in Organic Media

Abstract:

An organic solvent tolerant isolate A213 originating from soil samples were successfully isolated via direct plating method using 10g/L of toluene as the sole carbon source and transparent cycle plate assay method.It was identified as Yarrowia based on its characteris- tics.The results in shake flask cultivation showed that the suitable tipase producing media were(g/L):yeast extract 40,vegetable oil 10, MgSO₄·7H₂O1,KH₂PO₄ 5.Under optimal culture conditions (27℃and pH 6.5 ),the maximal lipase activity could reach 67.8 IU/mL.The optimal pH and temperature for the hydrolysis of p-nitrophenyl acetate by crude lipase were pH6.5 and 40℃. The enzyme was sta-ble under 70℃ and pH5.5～8.5. Then isolate A213 was found to produce the lipase which can synthesize L-ascorbyl palmitate in tert-amyl alcohol validaed by the thin-layer chromatography.