In vitro antibacterial efficacy of crude ethanolic leaf extract and alkaloidal fractions of phyllanthus amarus on URO-pathogens

Abstract

The phytochemistry and in vitro antibacterial efficacy of crude ethanolic leaf extract and alkaloidal fractions of Phyllanthus amarus on the Gram positive (Streptococcus sp, Staphylococcus aureus; Coagulase negative Staphylococcus sp and Enterococcus faecalis) and Gram negative bacteria (Escherichia coli, Enterobacter sp.; Serratia marcescens; Klebsiella sp and Pseudomonas aeruginosa) isolated from mid stream urine were carried out using standard microbiological and disc diffusion techniques. The preliminary phytochemical analysis of the ethanolic leaf extracts of P. amarus revealed the presence of phyto-constituents such as alkaloids (+++), tannins (+++), saponins (++), flavonoids (++), cardiac glycoside (+), free anthraquinones (++), deoxy-Sugar test (+) and phlobatanins (+), while combined anthraquinones was not detected. The results showed that P. amarus extracts exhibited varying degrees of inhibitory effects against both Gram positive and Gram negative bacteria isolated from urine samples. Highest mean zones of inhibition (14.3+1.0 mm) and activity index (0.97) were obtained at 40.0mgml^-1 among the Gram positive bacteria, while the highest mean zones of inhibition (14.5 + 0.5mm) and activity index (1.12) at 40.0mgml^-1 were obtained among the Gram negative. The results also showed that Coagulase negative Staphylococcus sp (CS03) was not sensitive to both 20.0mg/ml^-1 of crude extracts of P. amarus and alkaloidal fractions. Among the Gram negative, Enterobacter sp (ES03) was not sensitive to 20.0mg/ml^-1 of crude extracts of P. amarus, alkaloidal fractions and Streptomycin. Therefore, there is a need to consider the use of this potent ethanolic leaf extracts and the alkaloids for developing synthetic drugs against uro-pathogens.