In vitro antimicrobial assessment of seeds of selected medicinal plants in Sri Lanka

Abstract

Introduction: People are suffering from many noncommunicable diseases as a result of the COVID pandemic and the stress that has followed after it. Diabetes mellitus is a complex non-communicable disease and its incidence in Sri Lanka is almost high. While a number of antidiabetic medications are available, herbal management of diabetes is encouraged due to its low side effects and efficacy. Examining the antibacterial properties of anti-diabetic plants may be highly valued because, diabetics are chronic immunocompromised individuals who are more prone to microbial infections. To focus this aim, the present in-vitro antimicrobial assessment carried out for the seeds of selected four medicinal plants, such as Syzygium cumini (L.) Skeels, Sinapis alba L., Trigonella foenum-graecum L. and Nigella sativa L. that are commonly used for diabetes management in Sri Lanka. Materials and methods: Crude ethanol extract from the seeds has been studied for their antibacterial potential against three bacterial strains such as Enterococcus faecalis, Staphylococcus aureus and Escherichia coli by using agar well diffusion method in triplicates. The statistical analysis was performed using a one-way analysis of variance. Results: The seed extract of S. cumini showed the highest value of zone of inhibitions (E. faecalis: 24.70±037, S. aureus: 16.15±1.20 and E. coli: 10.37±1.51 mm) and S. alba exhibited the lowest value of zone of inhibition (1.08±2.65, 1.08±2.65, 0 mm) for all selected pathogens respectively and which were comparable to the positive control streptomycin (E. faecalis: 25.45±1.18, S. aureus: 21.08±0.26 and E. coli: 19.37±1.35mm). Conclusion: The result shows that S. cumini seed extract poses the highest antimicrobial activity in selected bacteria. Therefore, this seed is potential to be further developed as an herbal antibiotic for the management of infection in diabetes in future.