1. Department of Biological Chemical Engineering, College of Chemical Engineering and Materials Science, Tianjin University of Science and Technology , Tianjin 300457 , China
2. National Research Foundation , PO Box 2600 Pretoria 0001, South Africa
3. School of Life Science, University of KwaZulu Natal , Durban 4000, South Africa
4. Department of Biotechnology and Food Science, Faculty of Applied Sciences, Durban University of Technology , PO Box 1334 , Durban 4001, South Africa
5. Tianjin Key Laboratory of Industrial Microbiology , Tianjin 300457 , China