In anaerobic condition, the growth of S. typhimurium increased to OD600nm = 0.4 during 10 h
and then became stable at OD600nm = 0.35 until the final point. Only in anaerobic condition, Z.
officinale, Z. ‘Phlai Chomphu’ and A. galanga inhibited S. typhimurium (Fig. 3). The results are
in agreement with many previous reports indicated moderate or no antibacterial activity against
S. typhi or S. typhimurium