Table 2. The results of zeta potentials, unit: mV.

Strains	S. aureus	MRSA	E. coli
Blank	−30.5 ± 4.3	−29.7 ± 4.1	−31.3 ± 3.7
B3	−31.1 ± 2.9	−30.9 ± 3.3	−30.9 ± 3.1
P3	−21.2 ± 3.7	−19.8 ± 2.1	−20.3 ± 2.6
Y1	−31.3 ± 4.4	−30.6 ± 3.6	−31.5 ± 2.4

The bacterial cells were incubated with or without 5 μM of PSs, data were expressed as means ± standard deviation of three independent experiments.