Abstract

ANTIVIRAL AND ANTIBACTERIAL SUSCEPTIBILITY OF ACETONE LEAF EXTRACT OF COMBRETUM PANICULATUM

Nwobodo H. A.*

ABSTRACT

Leaf extract of Combretum paniculatum is used among some local folks in Nigeria for treating viral and bacterial infections. To understand the scientific basis for such practice, the antimicrobial activity of acetone leaf extract of Combretum paniculatum was investigated against selected viruses (Peste des petits ruminant virus (PPRV), Infectious bursal disease virus (IBDV), New castle disease virus (NDV)) and bacteria (Escherichia coli, Staphylococcus aureus, Bacillus cereus, Pseudomonas aeruginosa, Salmonella Typhimurium and Clostridium perfringens) using tissue culture, embryonated chicken eggs and agar well diffusion test respectively. The phytochemical analysis of the leaf was also performed using standard methods. Result showed that the leaf extract exhibited no activity against the viruses at concentrations less than or equal to 10-3.3, 10-3.6 and 10-3.6 mg/ml which were the highest concentrations not toxic to Vero cells, Chicken embryo fibroblast cells and 11 day old chicken embryo respectively, but inhibited the growth of Salmonella typhimurium and Bacillus cereus in a concentration dependent manner. At 50 mg/ml, 7 mm and 5 mm diameters of zone of inhibition were recorded against Salmonella typhimurium and Bacillus cereus respectively. With increase in concentration of the extract up to 400 mg/ml, there was a corresponding increase in zones of inhibition (33 mm and 24mm against Salmonella typhimurium and Bacillus cereus respectively). Higher minimum inhibitory concentrations (MICs) of 6.25 mg/ml and 12.5 mg/ml and minimum bactericidal concentrations (MBCs) of 12.5 mg/ml and 25.0 mg/ml against Salmonella Typhimurium and Bacillus cereus was observed compared with 0.30 mg/ml of the control (L-flox). Phytochemical analysis showed the presence of alkaloids (+ + +), tannins (+ + +), flavonoids (+), lipids (+), proteins (+ + +), reducing sugar (+ +), and saponins (+ + +), indicating the possible presence of bioactive agent capable of inhibiting the growth of Salmonella typhimurium and Bacillus cereus. Purification of the crude extract is necessary to determine the bioactive substances responsible for the observed antibacterial effect.

Keywords: Antimicrobial, Susceptibility, Phytochemistry, Combretum Paniculatum.