Table 5: Determination of anti-mutagenic activity of plant extracts in Salmonella typhimurium TA1535 against benzo[a]pyrene (B[a]P; 20 μM) in presence of S9 mix.

Treatment B[a]P mutagenicity at plant extract concentrations
(revertant colonies/plate; mean ± SEM (% reduction in B[a]Pmutagenicity))
Preexposure*Coexposure*
1 mg/mL5 mg/mL1 mg/mL5 mg/mL

B[a]P324.3 ± 21.5
I147.7 ± 5.9 (63)a109.0 ± 10.2 (77)a,b160.7 ± 10.5 (59)a150.0 ± 7.1 (62)a
II63.7 ± 11.1 (93)a52.7 ± 6.1 (97)a97.7 ± 6.7 (81)a93.7 ± 9.2 (83)a
III55.0 ± 4.7 (96)a63.3 ± 7.5 (93)a98.0 ± 7.8 (81)a91.7 ± 4.7 (83)a
IV54.0 ± 2.9 (97)a47.3 ± 3.7 (99)a95.3 ± 3.5 (82)a90.7 ± 9.3 (84)a
V92.3 ± 4.1 (83)a58.3 ± 7.3 (95)a,b111.7 ± 5.8 (76)a105.3 ± 8.7 (78)a

Plant extracts were incubated with bacteria either 30 minutes before B[a]P (preexposure) or incubated with the bacteria and B[a]P (coexposure). The spontaneous revertant colonies were 45.0 ± 4.9. aSignificant (P < 0.05) reduction (% of inhibition of mutagenicity indicated in parentheses) from revertant colonies seen with B[a]P. bSignificant difference (P < 0.05) between plant extract concentrations.