. 2020 Jul 14;25(14):3208. doi: 10.3390/molecules25143208

Table 1.

Combination index (CI) for phlorethols—X-ray irradiation interactions.

Concentration of CcPh, µg/mL	Dose of X-ray, Gy	Combination Effect, % of Control		Combination Index, CI *
Concentration of CcPh, µg/mL	Dose of X-ray, Gy	HT-29	HCT 116	HT-29	HCT 116
2.5	2	40	30	0.67879 ± 0.024	0.58038 ± 0.012
5	2	52	37	0.61559 ± 0.03	0.48424 ± 0.035
10	2	63	45	0.58341 ± 0.027	0.43194 ± 0.042
20	2	65	62	0.66600 ± 0.021	0.33167 ± 0.037

* The Combination Index (CI) is the quantitative measure of the degree of interaction between different treatments. CI values in the range of 0.9–1.1 indicate additive effect; and CI values greater than 1.1, antagonism. CI values in the range from 0.9 to 0.7 indicate slight synergism; and CI values less than 0.7, synergism. CI values were calculated according to the Chou and Talalay mathematical model for drug interactions using the CompuSyn software version 1.0 on the basis of the results of soft agar assay. Data represent mean CI calculated from three independent experiments ± standard deviations.