Table 3.
Nitrite scavenging ability of hot water extracts from root and aer ial part of S. palmata

	Concentration (μg/mL)	Extract		Control
		RHW	APHW	Ascorbic acid
		pH 1.2	100	5.86 ± 0.57^b1)	2.95 ± 0.00^c	52.38 ± 0.21^a
300	16.03 ± 0.42^b		14.28 ± 0.20^c	91.34 ± 0.51^a
500	26.91 ± 1.07^b		22.53 ± 0.56^c	93.67 ± 0.36^a
1,000	47.68 ± 0.14^b		40.12 ± 0.31^c	97.40 ± 0.28^a
2,000	63.06 ± 0.63^b		56.31 ± 0.62^c	98.06 ± 0.08^a
IC50	1,150.85 ± 7.33^b		1,610.25 ± 15.27^c	99.93 ± 0.16^a
pH 3.0	100		3.89 ± 0.45^b	3.33 ± 0.28^c	30.52 ± 0.69^a
	300	13.97 ± 0.49^b	12.57 ± 0.15^c	52.58 ± 0.94^a
	500	20.72 ± 0.77^b	18.70 ± 0.38^c	65.77 ± 0.65^a
	1,000	35.07 ± 0.85^b	30.07 ± 0.48^c	81.03 ± 0.45^a
	2,000	47.16 ± 0.92^b	39.26 ± 0.40^c	85.26 ± 0.43^a

pH 6.0	100	1.82 ± 0.65^b	2.82 ± 0.87^b	5.24 ± 1.01^a
	300	3.39 ± 0.38^b	3.99 ± 0.37^b	13.87 ± 0.63^a
	500	5.51 ± 0.88^b	5.84 ± 0.54^b	29.85 ± 1.44^a
	1,000	8.09 ± 0.51^b	8.50 ± 0.49^b	50.19 ± 0.51^a
	2,000	11.18 ± 0.77^b	10.60 ± 0.36^b	59.41 ± 0.58^a

Values represent the mean±SD and mean with different superscripts within the row are significantly different at p<0.05 by Duncan’s multiple range test. IC₅₀ values were determined by linear regression analysis