Evaluating the antimicrobial activity of thyme, lemon, and cinnamon essential oils against some multi-drug resistant pathogenic bacteria

Pathogens are the primary contributors to mortality rates in developing nations, with bacterial resistance to antibiotics amplifying the risk of hospitalization and extending the duration of hospital stays. The need for new antibacterial medications is rising as drug-resistant pathogens become more prevalent and threaten the efficacy of treatments for bacterial illnesses. So, our study's aim was to assess the antibacterial effects of cinnamon, lemon, and thyme essential oils (EOs) alone or in combination with several traditional antibiotics. Three multi-drug resistant (MDR) skin bacterial isolates were molecularly identified using the 16s rRNA gene sequencing technique and submitted to GenBank of accession numbers PP813714, PP813715, and PP813716. The antibacterial efficacy of different EOs was determined using the disc diffusion method. As a result, thyme oil was the most effective with minimum inhibitory concentration (MIC) = 0.125 mgmL-1followed by lemon oil with 0.25 mgmL-1 then, the cinnamon oil with MIC equals 0.5 mg mL-1. Using the oils alone proved to be more effective than using them in combination. Compared to when the antibiotics were used alone, the addition of oils increased the effectiveness of the antibiotics and increased their inhibition zones. Essential oils chemical composition was assessed using GC/MS with polonicumtoxin B, citral, and thymol as major compounds; this study addressed the issue of antibiotic resistance by offering a natural substance as an alternative to pharmaceutical therapies.