The objective of this research was to study the antibacterial activity of 16 samples of indigo dyed fabrics that are produced and sold in Sakon Nakhon Province. Effect of moisture and pH of indigo dyed fabrics on bacterial growth were also determined. The result of the study shows inhibition of S. aureus TISTR 746 and E. coli TISTR 073 by agar diffusion plate test all samples could inhibit Saureus TISTR 746 (accounted as 100%) and only 9 samples could inhibit E. coli TISTR 073 (accounted as 56.25%). Whereas the study of antibacterial activity by AATCC test method 100-2004 at 24 hours was found that the natural indigo dyed fabrics code A3-1 could inhibit both bacterial strains in the highest level. The result also shows the effect of moisture and pH of indigo dyed fabrics on bacterial growth it was found that the increased humidity levels of indigo dyed fabrics have effect on the reduction of the inhibition efficacy of both strains. While indigo dyed fabric with pH 3.0 was found to inhibit most of the growth of both strains. In addition images obtained using a scanning electron microscope (SEM) could clearly confirm the property of indigo dyed fabric on inhibition of S. Aureus TISTR 746 and E. coli TISTR 073.

The aim of this research was to study the antibacterial activities of crude extract with hexane from the leaves stems corms and roots of Acrostichumaureum L. by disc diffusion method against the pathogens viz. Bacillus cereus TISTR687 Staphylococcus aureus TISTR1466 Escherichia coli TISTR780 and Salmonella typhimurium TISTR292. The results revealed that the leaves extracts showed antibacterial activity onall of fourtested pathogenic bacteria with the inhibition zone of 9.20 0.37 8.92 0.09 6.62 0.48 and7.82 0.56 mm.respectively. While the stems corms and roots extracts showed antibacterial activity ononly B. cereus with the inhibition zone of 8.02 0.25 8.51 0.21 and 10.87 0.13 mm. respectively. This preliminary screening results demonstrated the potential of the extracts from various parts of Acrostichumaureum L. to be used as antibacterial agent and to be further researched and developed into innovative pharmaceutical and cosmetic products.