Antimicrobial and antioxidant role of the aerial parts of aconitum violaceum

Abstract

In the current studies, crude and subsequent fractions of Aconitum violaceum aerial parts were screened for their toxicity, antimicrobial effects as well as antioxidant potential. Phytochemically, the plant is enriched in alkaloids alongside anthraquinones (present in ethyl acetate fraction (AV3) and saponins (detected in chloroform fraction (AV2). In Brine shrimp lethality assay, AV3 was the most potent (59 %) in killing Artemia naupili larvae at a dose of 1000 µg/mL. AV3 exhibited strongest antimicrobial effect against the bacteria E. coli (80 %) and S. flexneri (76 %) as well as against the tested fungi, A. niger (86 %) respectively. However, chloroform fraction (AV2) was the most effective (almost 90 %) antifungal against A. niger and C. albicans. Overall, strong antioxidant activity was observed for AV3 with IC50 values of 120.04 ± 0.4 µg/mL (65.4 ± 0.01 standard) in DPPH and 125.1 ± 0.3 µg/mL (2.0 ± 0.03 standard) in ABTS free radical assays. AV3 showed promising inhibition against acetylcholinesterase (AChE) 70 ± 0.8 % and butyrylcholinesterase (BChE) 57 ± 0.2 % at dose of 100 µg/mL thus confirming a potent invitro cholinesterase inhibitory effect. The overall results indicated strong biological potential of ethyl acetate fraction obtained form A. violaceum and a possible new therapeutic source could be formulated from its pure isolates.