Table 4: Effect of benzene fraction of Murraya koenigii on the mutagenicity induced by benzo(a)pyrene with metabolic activation using Salmonella typhimurium strains.

TreatmentDose (µg/plate)Number of His+ revertants colonies/plate
TA97aTA98TA100TA102

Spontaneous143.7 ± 13.237.0 ± 3.0135.3 ± 9.5316.0 ± 14.5
Positive control (BP)1720.3 ± 28.5155.0 ± 7.6695.7 ± 17.0648.0 ± 17.1
  koenigii 12.5142.0 ± 18.350.3 ± 2.5132.7 ± 16.0265.0 ± 28.2
25156.0 ± 14.442.7 ± 3.5155.3 ± 17.2296.3 ± 17.6
50168.7 ± 21.735.0 ± 3.6 322.7 ± 31.1
100181.3 ± 27.128.0 ± 3.6175.3 ± 20.6340.3 ± 31.3
  koenigii+ BP12.5592.3 ± 44.5* (22.1)132.7 ± 19.2 (21.3)540.0 ± 50.1** (27.7)560.3 ± 31.2* (22.9)
25501.7 ± 36.6** (38.7)101.0 ± 19.3* (48.1)435.3 ± 46.1*** (48.2)501.7 ± 16.9*** (41.9)
50382.7 ± 35.6*** (61.2) (61.9)352.3 ± 30.7*** (65.1)436.0 ± 38.2*** (65.2)
100276.0 ± 26.5*** (82.4) (80.1)253.7 ± 21.4*** (84.9)382.0 ± 29.2*** (86.0)

  value treatment168.14949.036149.65167.488

  value0.9960.9820.9990.999

The data represented in the table is the mean ± SD values of three replicates. Mean values followed by asterisk are significantly different when compared to positive control at *P < 0.05; **P < 0.005 and ***P < 0.001. The values in parentheses are the inhibition rates of mutagenicity (%). Positive control: BP: benzo(a)pyrene.aNegative control; bPre-incubation test; : Linear regression analysis.