Visible Light-Induced Antibacterial Activity of Pigments Extracted from Dregs of Green and Black Teas

Figure 5

Percentage of bacterial inactivation after incubation of single broth cultures with various sensitizers under illumination of red LED for 30 min. The types of applied sensitizers were as follows: sterile 1% Tween 80 as the medium for pigments dispersion (control), chlorophyll a (Chl a), chlorophyll b (Chl b), pheophytin a (Pheo a), and pigments extracted from the dregs of green tea (GT) and black tea (BT). The error bars represent standard error of the mean for three repetitions in each treatment. The upper symbols denote statistical significance based on treatment to control comparison using Dunnett’s test at confidence level of 0.95 () and 0.99 (), whereas the different letters indicate significant differences ( < 0.05) among bacterial species in the same group of sensitizers.