Aqueous extract exhibited the least potency
among all. In DPPH free radical scavenging activity and
reducing power absorbance of both peppermint oil and chloroform
extract exhibited similar trends as observed in the case of
antioxidant capacity. Aqueous extract showed the least DPPH
scavenging activity (70.3 ±6.1) and reducing power
(0.4±0.3) akin to its antioxidant activity. The rest of the
leaves extracts showed the antioxidant capacity, DPPH scavenging
activity and reducing power in between those of chloroform
and aqueous extracts. The IC50 (lg/mL) of peppermint
oil by using DPPH scavenging method was found to be
15.2± 0.9 while for positive control BHT it was 6.1 ±0.3.