Antioxidant and antibacterial activity of Toddalia asiatica (Linn) Lam root extracts

Background: Toddalia asiatica (Linn) Lam is a woody vine that is used medicinally in China, India, and East Africa. The aim of the present study was to examine the antioxidant and antibacterial activity of the roots of Toddalia asiatica (Linn) Lam (TA). Materials and Methods: The antioxidant capacity of TA roots was determined using 1,1 iphenyl-2-picrylhydrazyl (DPPH), 2,2´-azino-bis (3-ethylbenzo-thiazoline-6-sulfonicacid) (ABTS), and the ferric reducing antioxidant potential (FRAP) assay. The antimicrobial activity of TA against Staphylococcus aureus (SA), methicillin-resistant S. aureus (MRSA), and extended spectrum β-lactamase positive S. aureus (ESBLs-SA) was screened. Results: Methanol and ethyl acetate extracts of TA exhibited strong antioxidant activity. The methanol extract had the highest antioxidant activity (DPPH, IC 50 =41.45 μg/mL; ABTS, IC 50 =8.34 μg/mL; FRAP=1304.8 ± 60.38 μmol Trolox equivalent (TE)/g), which was close to that of the positive control, butylated hydroxytoluene (BHT). The petroleum ether extract of TA showed the highest antimicrobial activity (SA, minimum inhibitory concentration (MIC) = 250 μg/disc; MRSA, MIC=125 μg/disc) when compared with that of ethyl acetate extract (SA, MIC=250 μg/disc) and methanol extract. Conclusions: Investigation of methanol, petroleum ether, and ethyl acetate extracts of TA root revealed robust antioxidant activity in methanol extracts and strong antimicrobial activity against SA and MRSA in petroleum ether extracts. Keywords: Toddalia asiatica (Linn) Lam; antioxidant; antibacterial