Supayang Voravuthikunchai1, Peter Howe2. 1. Department of Microbiology, Faculty of Science and Natural Product Research Center of Excellence, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand. supayang.v@psu.ac.th. 2. Clinical Nutrition Research Centre, School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, NSW 2308, Australia. peter.howe@newcastle.edu.au.