Corresponding author at: Research Group for Pharmaceutical Activities
of Natural Products using Pharmaceutical Biotechnology (PANPB), Faculty
of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002,
Thailand. Tel.: +66 43 202378x1510, 3622; fax: +66 43 202305.
E-mail address: kanok_ja@kku.ac.th (K. Jarukamjorn)