Phytochemical Analysis, Antioxidant and Antibacterial Properties of Spilanthes mauritiana Used Traditionally in Limpopo Province, South Africa

Spilanthes mauritiana belonging to the family Asteraceae, was screened for biological activity against bacterial pathogen. Antibacterial activity of the plant was investigated using microbroth dilution assay and bioautography. Total phenols and tannins of the extract were 52.47 ± 2.29 and 23.9 ± 1.18 as mg of gallic acid equivalents, respectively. Total flavonoid content was 25.1 ± 0.79 as mg of quercetin equivalents. Free radical scavenging activity of constituents in all the extract, against 2,2-diphenyl-1-picrylhydrazyl showed minimal activity. All extracts contained compounds with antibacterial activity against tested pathogens. Hexane extract had an average minimum inhibitory concentration value of 2.50 mg/mL, followed by methanol extract (1.72 mg/mL), acetone and dichloromethane extracts (1.96 mg/mL). The present study revealed the presence of compounds in S mauritiana with potent antibacterial activity against tested pathogens that are exhibiting the observed activity independent of other constituents contained in the extracts.