BTL2-pET28b ( +) recombinant plasmid construction (a), and protein purification profile of recombinant lipase BTL2 by SDS-PAGE (b). MW molecular weight marker, IN Input samples, FT flow-through samples, W washes samples (W1–W3), E eluted fractions samples (E1–E9). 2 μg was the loading amount of purified recombinant BTL2