Antibacterial activities of sawdust and stem bark of Sasswood tree (Erythrophleum suaveolens, Guill. & Perr. Brenan, 1917) extracts against selected wood bacteria

Abstract

This study assessed the antibacterial properties of sawdust and stem bark of Erythrophleum suaveolens extracts on selected wood bacteria. Erythrophleum suaveolens samples were collected, dried and macerated by dissolving 1 Kg and 0.60 Kg of stem bark and sawdust respectively into 1 L of n-hexane, ethyl acetate and methanol. Sporfloxacin ciprofloxacin and cefuroxine antibiotics were used as control. The mixture was left for 24 hours then filtered and the filtrates evaporated to dryness. Qualitative phytochemical screening, zone of inhibition, minimum inhibitory and Bactericidal Concentrations (MIC/MBC) were determined according to standard methods. Tannins, steroids, saponins, glycosides, flavonoids, carbohydrates anthraquinones and alkaloids phytochemicals were present in E. suaveolens extracts. Zone of inhibition (32 – 37 mm) of antibiotics on test bacteria compared favourably with 17 – 24 mm of E. suaveolens extracts. Erythrophleum suaveolens ethyl acetate and methanol E. suaveolens extracts inhibited Staphylolococus aureus, Ralstonia solanacearum, Proteus mirabilis, Enterococcus faecium and Acidobacterium capsulatum growth at MIC of 10 mg/mL and n-hexane extracts at 20 mg/mL. At MBC of 20 mg/mL methanol stem bark extract completely killed most test bacteria. Methanol extracts were the most active extracts. The study has shown that E. suaveolens extracts can be explored in the control of plant diseases caused by test bacteria in the study.

Key words: Antibacterial, E. suaveolens, extract, phytochemicals, zone of inhibition