Table 5.

DPPH scavenging activities in different parts of L. pumila under different nitrogen levels. BHT and α-tocopherol were used as positive controls.

Nitrogen levels	Extract source	Inhibition % a
0 kg N/ha	Leaves	61.3 ± 1.6 c
	Stems	57.1 ± 1.1 c
	Roots	51.2 ± 1.0 c
90 kg N/ha	Leaves	50.8 ± 1.0 d
	Stems	48.1 ± 0.9 d
	Roots	46.7 ± 0.4 d
180 kg N/ha	Leaves	46.4 ± 0.2 e
	Stems	42.7 ± 0.9 e
	Roots	40.2 ± 1.2 e
270 kg N/ha	Leaves	37.2 ± 2.2 f
	Stems	32.1 ± 1.2 f
	Roots	30.6 ± 3.2 f
Controls	BHT	65.6 ± 1.3 b
	α-tocopherol	76.3 ± 1.2 a

All analyses are mean ± standard error of mean (SEM); N = 18. Means not sharing a common single letter are significantly different at P ≤ 0.05.

^aResults expressed in percent of free radical inhibition.