Anti Bacterial Activity of Ricinus Communis Extracts against Common Human Pathogens Obtained from Surgical Wound Infections in a Tertiary Care Hospital of Semi-urban Set Up at Andhra Pradesh, India

Introduction: A number of medicinal compounds are manufactured with great exactness and simply from easily available raw materials at normal temperature and pressure from highly sophisticated chemical factories called plants and its parts. There are many methods of research associated with the medicinal plants and traditional medicine has shown very little attention in modern research and less effort has been done to upgrade the practice of using medicinal plants.

Aim: To assess the antibacterial activity of Ricinus communis leaf extracts against common human pathogens obtained from surgical wound infections in a tertiary care teaching hospital.

Materials and Methods: This cross-sectional study was conducted in the Department of Microbiology of a Tertiary Care teaching Hospital for a period of one month in January 2021. The pathogenic bacteria isolated from the surgical wounds were used for this study and the antibacterial activity of medicinal herb leaf extract Ricinus communis L. was investigated against gram positive bacteria and gram negative bacteria. Antimicrobial susceptibility testing was done as per Clinical and Laboratory Standards Institute (CLSI) guidelines by Kirby-Bauer disc diffusion technique using the extract, ampicillin as positive control and Dimethyl Sulphoxide (DMSO) as negative control. The zones of inhibition were measured using a special measuring scale. The Minimum Inhibitory Concentration (MIC) and the Minimum Bactericidal Concentration (MBC) of the medicinal plant were also tested against the same pathogenic bacterial strains that were isolated. The statistical analysis of frequency and mean were calculated and the results were tabulated.

Results: The methanol crude extract of plant leaves (300 mg/mL) showed significant zone of inhibition against gram positive and gram negative bacteria. Comparatively, very less zone of inhibition was obtained from the aqueous unrefined extract of medicinal plant when compared to the methanol solvent extracts. DMSO was taken as negative control and no zone of inhibition was seen. Ampicillin (10 μg) was taken as positive control and has shown significant zone of inhibition against the isolated bacterial pathogens from wound infections. The best MBC value was observed in the methanol extract and in aqueous extract, the growth was extensive and full.

Conclusion: Ricinus communis concentrated methanol leaf extract had shown effective antibacterial activity in comparison with the standard ampicillin. Based on further chemical, pharmacological and molecular studies in the future on this leaf extract and identify phytochemical constituents in the leaf, seed, stem, roots and to screen other potential bioactivities of the leaf extract may be recommended for the treatment of wounds.