Resistance Profile of Bacteria Isolated from Diabetic Wounds: Phytochemicals and Antibacterial Studies of Eriosema robustum Leaf Extracts

Abstract

Diabetics are susceptible to severe trophic problems and wounds, which are frequently referred to as “unhealable wounds”. Untreated diabetic wounds provide an ideal habitat for the growth of bacteria, which can eventually develop resistance to standard treatments and need amputation. This study aimed to assess the in vitro antibacterial activity of ethanolic and aqueous extracts of Eriosema robustum leaves on the same bacterium, as well as the resistance profile of bacteria isolated from diabetic wounds to conventional antibiotics. Thirty samples from diabetic wounds were collected at the Baleveng Hospital, subjected to bacteria isolation and antibiotics resistance tests using the disk diffusion method. On the other hands, leaves of Eriosema robustum were collected, hydroethanolic extraction were performed. The extract obtained was used for the antibacterial (by determination of the MIC) and antioxidant (DPPH and FRAP tests) activities as well as phytochemicals composition (using HPLC methods) assessment. Amon the 30 samples analyzed, 19 (63.33 %) showed bacterial infections and Staphylococcus aureus was the most common pathogen (48 %), followed by Pseudomonas aeruginosa (24 %), Klebsiella pneumoniae (19 %), and Streptococcus agalactiae (9 %). Fifty percent (50 %) of S. aureus isolates were MRSA (methicillin-resistant S. aureus). The MIC value obtained 64 μg/mL against S. aureus, Streptococcus agalactiae and Pseudomonas aeruginosa. Phytochemicals analysis of fractions from the 70 ° hydroethanolic leaves of Eriosema robustum revealed the presence of coumarin, gallic acid, quinoline, vanillin, ascorbic acid, caffeic acid, kaempferol, and cinnamic acid. The antibacterial and antioxidant potential of the extracts highlighted in this study could make this plant a good avenue for the discovery of new molecules effective against infected diabetic wounds.