Table 7: Effects of plant extracts on benzo[a]pyrene (B[a]P) mutant frequency.

TreatmentMutant frequency and % of B[a]P#
Preexposure*Coexposure*
1 mg/mL5 mg/mL1 mg/mL5 mg/mL

B[a]P9.54 (100)
I4.44 (46)a2.82 (30)a4.83 (51)a3.88 (41)a
II1.95 (20)a1.35 (14)a2.99 (31)a2.40 (25)a
III1.83 (19)a1.57 (16)a3.27 (34)a2.28 (24)a
IV1.59 (17)a1.36 (14)a2.80 (29)a2.61 (27)a
V2.41 (25)a2.27 (24)a2.92 (31)a4.10 (43)a

Calculated from mutant colonies (Table 5)/viable colonies. *Plant extracts were incubated with bacteria either 30 minutes before B[a]P (preexposure) or incubated with the bacteria and B[a]P (coexposure). aSignificant difference (P < 0.05) from B[a]P.