On the surface of the untreated and the coated wool fibers, it can be seen that Escherichia coli cells with flagella (long, thin structures) are plump and each individual bacterium is columniform or oblong shaped. With the presence of capsaicin, large amounts of collapsed or non-viable bacteria were found on the capsaicin-coated fabric. This suggested that capsaicin inhibited the normal bacteria growth process.