Nont Thitilertdecha a, Aphiwat Teerawutgulrag b, Nuansri Rakariyatham b,*
a Division of Biotechnology, Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand
b Department of Chemistry, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
Received 27 June 2007; received in revised form 25 January 2008; accepted 30 January 2008
Abstract