Direct purification of Burkholderia Pseudomallei lipase from fermentation broth using aqueous two-phase systems. حسب Ooi, Chien Wei, Tey, Beng Ti, Hii, Siew Ling, Ariff, Arbakariya, Wu, Ho Shing, Lan, John Chi Wei, Juang, RueyShin, Mustapa Kamal, Siti Mazlina, Chuan, Ling Tau