Antibacterial activities of Melissa officinalis (Lamiaceae) aerial parts extracts against bacteria isolated from the oral microflora, and their antioxidant properties

Abstract

Dental caries and periodontal diseases are common oral conditions associated with the formation of dental plaque. Dental plaque is composed of the oral microbiota and accumulates on the tooth surface. Despite the development of numerous antiseptic agents to control bacterial growth, the issue of bacterial resistance has prompted scientists to explore new avenues. As the problem of bacterial resistance continues to grow, studies in this field become increasingly crucial. Medicinal plants offer the best resources for this purpose, and Melissa officinalis L. is one such plant. This study aims to determine the antibacterial and antioxidant activities of Melissa officinalis against bacteria isolated from the oral microbiota. In the study, 8 bacteria were used as the organism source, and Melissa officinalis was utilized as the plant source. The extraction of the plant was carried out using ethanol, methanol, and water. All extracts were evaluated for their antibacterial activities using the disk diffusion method. Antioxidant activity studies were conducted using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method. At the end of the study, the highest antibacterial activity was obtained from the ethanol extract of Melissa officinalis, with a 26 mm inhibition zone diameter against Staphylococcus epidermidis MBKK7. The highest antioxidant activity was determined to be 87.34% DPPH radical scavenging activity from the methanol extract of Melissa officinalis. As a result, it has been determined that Melissa officinalis exhibits both high antibacterial and antioxidant activities. It can be suggested that M. officinalis may serve as an effective natural protector against oral pathogens.