Antibacterial Activity of Lawsonia inermis Leaf Extracts against Multidrug-resistant Pseudomonas aeruginosa from Infected Wounds

Abstract

Background: Wound infection comprises numerous different organisms that have the ability to surface colonization of wounds. Multidrug-resistant Pseudomonas aeruginosa is one of the pathogenic bacteria associated with wound infections. Aim: This study isolated and identified multidrug-resistant Pseudomonas aeruginosa from infected wounds and determine the antibacterial activity of Lawsonia inermis leaf extracts against it. Design: This is a Clinical and laboratory-based study involving patients with defined cases of wound infections. Place and Duration of Study: This study was conducted in the Microbiology (Bacteriology) laboratory of Specialist Hospital, Bauchi, Nigeria, from February to November 2021. Methods: Twenty-eight (28) Pseudomonas aeruginosa isolates were recovered from 179 wound swabs using standard laboratory procedures and were screened for multidrug-resistant patterns according to the Kirby-Bauer disc diffusion method. Antibacterial efficacy of the aqueous, ethanolic, and methanolic leaf extracts of Lawsonia inermis was tested against the multidrug-resistant isolates using agar well diffusion techniques. The zone of inhibition was measured and the differences between means were statistically analyzed (p<0.05). Results: A total of twenty-eight (28) multidrug-resistant Pseudomonas aeruginosa were confirmed, showing resistance to Amoxicillin (64.3%), Ceftazidime (85.71%), and Cefotaxime (78.57%) but sensitivity to Imipenem (95.5%). The phytochemical screening revealed the presence of flavonoids, glycosides, saponins, steroids, and tannins among others. MDR P. aeruginosa was inhibited at varied concentrations of the extracts with the diameter mean zone of inhibition increasing as the concentration increased. The Methanol extracts showed the highest antibacterial activity against MDR P. aeruginosa with a mean zone of inhibition of 9.500±0.288mm at 400mg/ml. Conclusion: These results indicated that Lawsonia inermis leaf extracts possess antibacterial activities on Multidrug-resistant Pseudomonas aeruginosa which could be a good source for the production of plant-based antibacterial drugs., although somewhat less than the synthetic standard drugs (Imipenem) having a mean of 13.83±0.288mm.