Determination of total phenolic and flavonoid content, antimicrobial and antioxidant activity of a root extract of Arisaema jacquemontii Blume

We evaluated the antioxidant and antimicrobial activity of a methanolic extract of the roots of Arisaema jacquemontii. Antioxidant activity was determined in the 1,1-diphenyl-2-picryl-hydrazyl (DPPH), nitroblue tetrazolium (NBT) and ferric reducing power tests. The extract had significant antioxidant activity in all assays, with values of 64.16 ± 0.19% in the DPPH and 62.16 ± 0.17% in the NBT assays, and reduced Fe3+ ferricyanide complex to the ferrous form (Fe2+). Antibacterial activity and minimum inhibitory concentrations were calculated by the broth dilution method. The root extract prevented the growth of both Gram-positive and Gram-negative bacteria, at a minimum inhibitory concentration of 0.24–0.41 mg/mL. Antifungal activity, measured as inhibition of mycelium growth, was 28.32–36.50%. The antimicrobial and antioxidant activities of the extracts were positively associated with the total phenolic and flavonoid contents of the extract.