Table 1. DPPH and nitrite radical scavenging activities and reducing power of water and methanol extracts from N. nucifera leaves.

Sample (μg ml−1)	*Control (μg ml−1)	DPPH radical scavenging activity (%)			Nitrite radical scavenging activity (%)			Reducing power activity (absorbance at 700 nm)
		Water extract	Methanol extract	Ascorbic acid	Water extract	Methanol extract	Ascorbic acid	Water extract	Methanol extract	Ascorbic acid
100	50	0.59±0.42	16.84±1.54	22.07±0.66	5.41±1.47	14.19±0.49	15.6±2.76	0.08±0.00	0.12±0.00	0.27±0.01
200	100	5.19±0.88	25.13±0.29	47.58±0.42	12.75±0.62	21.33±1.94	59.29±2.34	0.11±0.00	0.22±0.00	0.51±0.02
500	150	16.29±1.70	56.26±2.23	71.64±0.21	23.20±1.10	47.43±2.07	88.94±2.30	0.16±0.01	0.76±0.01	0.80±0.01
1000	200	28.30±1.13	86.67±0.20	93.00±0.24	43.42±1.14	54.76±1.84	97.05±0.54	0.20±0.02	0.89±0.01	1.06±0.02
** IC50 (μg/ml)		1699.47	514.36	106.48	1141.33	784.02	95.51	-	-	-

All data are expressed as the mean ± SD (n = 3).

*Ascorbic acid was used as a positive control for the DPPH radical scavenging, nitrite radical scavenging, and reducing power activity assays.

** IC₅₀ (μg ml⁻¹): concentration at which 50% of the activity is inhibited.