Phytochemical Analysis, In Vitro Free Radical Scavenging, and LDL Protective Effects of Different Solvent Fractions of Calotropis procera (R.) Br. Root Bark Extract

Table 2

IC₅₀ values of CMRME and its solvent fractions on different in vitro radical systems tested.

Extract/fractions	DPPH scavenging	NO radical scavenging	H2O2 scavenging	^•OH^− radical scavenging	^•O2^− anion scavenging	Fe³⁺ ion chelating	LDL oxidation inhibitory
	IC50 (μg/ml)
CPRME	619.77 ± 13.78^b#	355.80 ± 14.30^b#	594.06 ± 11.12^b#	635.09 ± 11.21^b#	1029.83 ± 20.92^b#	943.42 ± 9.44^b#	1316.01 ± 13.14^b#
HF	2298.29 ± 63.72^n	2015.64 ± 43.50^n	2245.78 ± 64.67^n	4843.65 ± 141.65^n	2202.07 ± 55.91^n	1374.39 ± 20.62^n	971.54 ± 9.49^a#
DMF	482.53 ± 12.16^a^,b#	249.87 ± 7.52^a^,b#	532.47 ± 9.32^ns,b#	564.81 ± 10.84^ns,b#	657.85 ± 12.14^a^,b#	804.77 ± 7.91^a#,b#	795.31 ± 10.21^a#,b
EAF	369.87 ± 7.58^a^,b#	132.31 ± 5.78^a#,b#	396.85 ± 6.13^a^,b#	195.39 ± 4.95^a^,b#	741.90 ± 12.5^a#,b#	627.01 ± 8.99^a#,b#	452.57 ± 8.61^a#,b#
MF	794.35 ± 13.43^n,b#	542.41 ± 8.32^n,b#	665.14 ± 8.39^n,b#	1196.09 ± 13.91^n,b#	1716.60 ± 54.34^n,b#	614.73 ± 10.87^a#,b#	1743.17 ± 22.27^n,b#
AF	1568.93 ± 38.14^n,b#	1096.96 ± 14.95^n,b#	887.41 ± 9.07^n,b#	1993.07 ± 35.20^n,b#	1889.88 ± 47.40^n,b	1228.80 ± 13.07^n,b#	2930.62 ± 62.47^n,b#
Ascorbic acid (ASA)	30.42 ± 2.12^a#,b#	53.81 ± 3.51^a#,b#	45.38 ± 2.39^a#,b#	57.23 ± 3.68^a#,b#	91.53 ± 4.71^a#,b#	150.03 ± 3.41^a#,b#	NA

IC₅₀ values are expressed as mean ± SEM (n = 3). IC₅₀ of CPRME (crude extract) is compared with that of different solvent fractions. ^a, ^a, ^a, ^a# when compared with CPRME and ^b, ^b, ^b# when compared with HF (hexane fraction). ns: not significant. n: indicates a higher IC₅₀ than CPRME and therefore, lower radical scavenging activity. NA: no standard was used. The results of LDL oxidation assay of crude extract and solvent fractions were compared with positive control (native LDL with CuSO₄ only) CPRME: Calotropis procera root bark methanol extract; HF: hexane fraction; DMF: dichloromethane fraction; EAF: ethyl acetate fraction; MF: methanol fraction; AF: aqueous fraction.