Evaluation of antibacterial, phytochemical screening and GCMS profile of Paullinia pinnata Linn. leaf extracts against clinical wound isolates

Abstract

This study investigated the antibacterial properties, phytochemical constituents, and mode of action of Paullinia pinnata extracts on  clinical wound isolates, and spectral features of the most active fraction. The Paullinia pinnata leaf was subjected to ethanol extraction  and resulting solvent extract' concentrated to crude extract (Pp CE)  using rotary evaporator at 4 - 40 ^oC followed by fractionation with  column chromatography. The antimicrobial effects of the extracts were determined against the test organisms using agar diffusion  methods. Investigation of phytochemical constituents of Paullinia pinnata crude extract (Pp CE) and Paullinia pinnata ethyl acetate fraction (Pp EA) were carried out using appropriate methods. The constituents of the plant were further determined using GC-MS and FT- IR. The data obtained showed that the antibacterial activity of crude extract Pp CE, at a concentration of 35 mg/ml, had the highest zone  of inhibition (22.00 mm) against Staphylococcus sp. (C1). The MIC and MBC recorded were 2.19 and 17.50 mg/mL respectively.  Phytochemical screening of Pp EA detected alkaloid, terpenoid, saponin, phenol, carbohydrate, and resin as found in the Pp CE, but with  additional cardiac glycoside and sterols. The Pp CE fraction attained appreciable rate of kill against representative strains, likely achieved  by the antibacterial compounds present in the plant extract. The GC-MS revealed trans-13- Octadecenoic acid as the major constituent of  Pp EA fraction at 23.25%. The FT-IR of the Pp EA fraction unveiled hydroxyl group, (C=O) carbonyl group of ketone/aldehydes and C-C  skeletal vibrations. Thus, this study suggests that the Pp EA fractions possess some antibacterial activities and can be considered for   development into therapeutic drugs.