TABLE 4.

Calibration curves and EC₅₀ value of C. retusa leaf extracts on DPPH free radical.

Samples	Calibration curves	R 2	EC50/μg·mL−1
VC	y = 8.2783x + 0.5665	0.9984	5.97
Raw extract	y = 1.2957x − 0.2415	0.9998	38.78
10%	y = 0.4605x − 1.0059	0.9987	110.76
20%	y = 1.1638x − 1.9098	0.9958	44.60
30%	y = 1.3258x + 0.0283	0.9973	37.69
40%	y = 1.361x − 0.6849	0.9991	37.24
50%	y = 1.9803x + 2.3228	0.9916	24.08
60%	y = 1.0155x − 0.4055	0.9995	49.64