Table 1. Means ± standard deviation (SD) of histidine revertant colonies (obtained from three independent experiments carried out in triplicate), mutagenic index (MI), and inhibition percentage of mutagenicity (IP) for two tester strains of Salmonella typhimurium, TA98 and TA100, after treatment with different doses of the chalcone (E)-1-(2-hydroxyphenyl)-3-(4-methylphenyl)-prop-2-en-1-one) (2HMC).

Treatment	Mutagenicity				Antimutagenicity
	TA 98		TA 100		TA 98		TA 100
	Mean ± SD	MI	Mean ± SD	MI	Mean ± SD	IP (%)	Mean ± SD	IP (%)
Negative control1	20.66 ± 1.00A	1.00	143.00 ± 8.71A	1.00	21.99 ± 0.33	_	164.66 ± 38.08	_
Positive control2	509.55 ± 18.76	24.66	2157.66 ± 141.86	15.08	514.10 ± 80.52C	_	2088.33 ± 264.04C	_
2HMC 1 μg/plate	19.88 ± 3.02A	0.96	129.33 ± 14.64A	0.90	285.33 ± 64.45D	46.5	1549.00 ± 25.06D	28.0
2HMC 10 μg/plate	14.77 ± 1.07B	0.71	86.33 ± 8.96B	0.60	174.10 ± 10.80D	69.1	1508.33 ± 280.57D	30.2
2HMC 50 μg/plate	18.99 ± 0.87A	0.91	78.33 ± 12.22B	0.54	244.55 ± 56.07D	54.8	1453.00 ± 201.16D	33.1
2HMC 100 μg/plate	16.21 ± 0.51A	0.78	84.00 ± 6.08B	0.58	187.66 ± 27.56D	66.4	1530.66 ± 112.69D	29.0
2HMC 500 μg/plate	17.10 ± 2.26A	0.82	77.00 ± 7.55B	0.53	100.88 ± 6.44D	83.9	1443.00 ± 152.67D	33.6
2HMC 1000 μg/plate	15.33 ± 1.33B	0.74	68.00 ± 9.64B	0.47	64.99 ± 0.87D	91.3	1445.33 ± 98.33D	33.5

¹Negative control: 20 μL dimethylsulfoxide (DMSO).

²Positive control: 0.5 μg 4-nitroquinoline-1-oxide (4NQO) per plate for TA98 and 3.0 μg of sodium azide for TA100.

All values are means ± SD of three independent experiments.

Statistical analysis: one-way ANOVA and the Tukey’s test. Mutagenicity:

^ANo significant difference in comparison with the negative control (p > 0.05).

^BSignificant difference in comparison with the negative control (p < 0.05). Antimutagenicity:

^CNo significant difference in comparison with the positive control (p > 0.05).

^DSignificant difference in comparison with the positive control (p < 0.05).