Phytochemical composition and antimicrobial potential of

Background and Aim: The rise of antimicrobial resistance in veterinary medicine is a significant concern, particularly for pathogens responsible for skin infections. Although Materials and Methods: The aerial parts of stevia plants were extracted using hexane in a Soxhlet apparatus. Total phenolic and flavonoid contents were quantified using colorimetric assays. The volatile oil content was analyzed using gas chromatography-mass spectrometry (GC-MS). The antimicrobial activity of stevia extract against Results: The stevia extract yield was 3.59% of the dry plant weight with 259.96 ± 23.66 mg gallic acid equivalent (GAE)/g extract of total phenolics and 247.41 ± 19.92 mg quercetin equivalent (QE)/g extract of total flavonoids. GC-MS analysis identified major volatile components, including N-acetyl-14, 15, 16-trinorlabd-8(17)-en-13-amine (37.70% of peak area), phytol (11.02% of peak area), (-)-spathulenol (9.46% of peak area), n-hexadecanoic acid (8.01% of peak area), and (diphenylphosphinoyloxymethyl) dimethylsilane (7.59% of peak area). The minimum inhibitory concentration of the extract against the tested microorganisms ranged from 0.25 to 128.00 mg/mL. Time-kill kinetics exhibited time- and concentration-dependent germicidal effects. E-SEM and cell leakage analyses indicated that stevia extract compromised microbial cell membrane integrity. A spray formulation containing 10% w/w stevia extract displayed excellent eradication efficacy, achieving a 99.9999% reduction of Conclusion: Stevia extract is an effective antimicrobial against