Table 3.

Antimutagenic activity assay for aqueous extract of C. nervosum against various mutagens using S. typhimurium.

Test compounds	Average of His+ revertant colonies
	AF-2 1 ug/ml	AFB1 0.16 ug/ml	MeIQ 0.05 ug/ml
Standard mutagen	185±19.2	428±75.3	181±12.9
C. nervosum extract 100 mg/ml	178±17.5 (3.8)	314±43.7 (29.2)	134±6.0 (27.3)
C. nervosum extract 150 mg/ml	N.A.	254±41.6* (34.1)	69±3.5* (62.3)
C. nervosum extract 200 mg/ml	142±14.0 (23.8)	N.A.	N.A.

AF-2; 2-(2-furyl)-3-(5-nitro-2-furyl)-acrylamide, AFB1; aflatoxin B1, MeIQ; 2-amino-3,4-dimethylimidazo[4,5-f]quinoline, DW; distilled water, N.A.; not analyzed

The number of spontaneous revertant colonies range from 17±2.4–21±3.7. Parentheses indicated the percentage inhibition of the extract against each mutagen.

^*Significant difference in comparison with positive control (p<0.05)