Figure 4 shows an example of the results from the parallel streak method. The fabric coated with capsaicin inhibited bacteria growth under the covered area. In comparison, there was a moderate to heavy growth under the control-I sample (sol-gel coated, without capsaicin). To understand if the antibacterial activity of capsaicin is inhibitory or bactericidal, the morphology of Escherichia coli from different samples was investigated (Figure 5).