The DPPH radical scavenging activity of CJSPE was evaluated by
method as described by Kumaran and Karunakaran (2006) with
slight modification. Briefly, 0.5 ml DPPH solution (0.05% w/v in
methanol) was mixed with serial dilution of (25 to 200 g/ml, in
methanol) of CJSPE and mixture was incubated for 30 min at room
temperature. Absorbance of reaction mixtures were measured at
517 nm against the blank, which contained all reagents except the
test compound. DPPH radical scavenging activity was calculated by
using following formula: