Study of the Effect of Castor Leaves Extract against Bacteria Isolated from Foot Infection in Diabetic Patients

Abstract

Medicinal plants play a vital role in the health care. The aim of the present study was to determine the antimicrobial activity of Ricinus communis leaves extract with different concentration (100 mg/ml, 50 mg/ml and 25 mg/ml) by agar disc diffusion assay against 30 multi-drugs resistant bacteria isolated from patients with diabetic foot infection in Khartoum State. The study was conducted during period of May to July, 2018 . Wound swab samples were collected from both gender (68 males and 32 females). The samples were transported to the Research laboratory of Sudan University of Science and Technology for processing. Out of 100 swab samples investigated 96 samples showed positive bacterial growth in culture media that used for isolation of bacteria, then identified by conventional method and sensitivity test were also done to detect the activity of the selected antibiotic discs and the leave extract against selected isolated strains. The percentage of Gram negative isolates were found 56 organisms )58.3%( and Gram positive bacteria were found 40 organisms 41.7%. The identified species were Staphylococcus aureus 37(38.5%), Pseudomonas aeruginosa 15(15.6%), Escherichia coli 12(12.5%), Klebsiella pneumonia 13(13.5%), Proteus mirabilis13 (13.5%), Staphylococcus epidermidis and Citrobacter species were isolated in low frequency3( 3%) . The activity of selected standard antimicrobial agents were tested and showed that there was a high rate of resistance to most of them except Imipenem antibiotic which had strong positive activity against all isolates. The sensitivity of isolated bacterial strains to different concentrations of extract was done and the extract showed a good antibacterial activity against most tested bacterial strains, with inhibition zone ranged from 9 to 20mm. The present study suggests that the ethanol extract of this medicinal plant contain compounds that could be useful as an alternative to synthetic microbicides and are being used to the development of a novel broad spectrum antibacterial formulation.