Phytochemical Screening and Antibacterial Activity of Cynodon dactylon Extracts against Escherichia coli

Aims: To determine the phytochemical constituents and antibacterial potential of Cynodon dactylon leaf extracts against Escherichia coli.

Study Design: Experimental short-term prospective study.

Place and Duration of Study: The study was conducted in Kampala International University-Western Campus Teaching Hospital (KIU-WCTH), Microbiology Laboratory in Bushenyi District, Western Uganda, between June to December 2017.

Methodology: The presence of phytochemical constituents was determined using standard method whereas the antibacterial activity of C. dactylon extracts against susceptible E. coli ATCC 25922 and resistant E. coli BAA-2469 was determined by agar well diffusion method.

Results: The C. dactylon extract was found to contain flavonoids, saponins, tannins, steroids and glycosides except for the absence of Alkaloids in both extracts. The C. dactylon ethanol and aqueous extracts showed antibacterial activity against susceptible E. coli ATCC 25922 and resistant E. coli BAA-2469. Ethanol extract of C. dactylon had a mean zone of inhibition of 24.3±0.6 mm and 20.3±0.6 mm against the susceptible and resistant strains of E. coli respectively and aqueous extract exhibited a mean zone of inhibition of 19.3±0.6 mm and 16.3±0.6 against the susceptible and resistant strains of E. coli respectively as compared to the standard positive control (ciprofloxacin) which showed a mean zone of inhibition of 47.5±0.9 mm and 43.2±0.3 mm against the susceptible and resistant strains of E. coli respectively.

Conclusion: The C. dactylon extract was found to contain flavonoids, saponins, tannins, steroids and glycosides except for the absence of Alkaloids in both extracts. The C. dactylon ethanol and aqueous extracts showed antibacterial activity against the susceptible E. coli ATCC 25922 and resistant E. coli BAA-2469.