Purification and biochemical characterization of recombinant Persicaria minor β-sesquiphellandrene synthase oleh De-Sheng Ker, Sze Lei Pang, Noor Farhan Othman, Sekar Kumaran, Ee Fun Tan, Thiba Krishnan, Kok Gan Chan, Roohaida Othman, Maizom Hassan, Chyan Leong Ng