Evaluation of Enzyme Inhibition and Anti-Quorum Sensing Potentials of <i>Melaleuca alternifolia</i> and <i>Citrus sinensis</i> Essential Oils

In this study, Melaleuca alternifolia (Maiden and Betche) Cheel (tea tree) oil C. sinensis (L.) Osbeck (orange) was procured, their chemical compositions were characterized by gas chromatography coupled with mass spectrometry, co-injection using authentic samples. The oils rich in monoterpene hydrocarbons making up 84.5% of 48.9% M. oils. High amounts oxygenated monoterpenoids also identified (9.6%) (49.3%) three most abundant compounds limonene (71.2%), linalool (5.5%), β-myrcene (5.1%) sinensis, terpinen-4-ol (45.6%), γ-terpinene (19.4%) α-terpinene (9.3%) alternifolia. Enzyme inhibitions (anticholinesterase, antiurease, antityrosinase) both essential evaluated. acetylcholinesterase assay, had inhibition concentration (IC 50 ) values 153.7 ± 1.25 96.4 1.0 µg/mL, respectively as compared to 5.42 0.11 µg/mL for galantamine, while butyrylcholinesterase = 85.6 0.7 µg/mL) 127.8 0.6 exhibited moderate activities galantamine 45.8 0.8 µg/mL). the urease inhibitory activity, showed 48.4% 0.9% 30.6% 0.7% at 200 concentration, respectively. Quorum sensing (QS) mediated violacein production Chromobacterium violaceum CV12472 inhibited 100% minimum (MIC) showing QS diameter zones 22.5 0.4 mm 14.3 0.5 oils, MIC concentration. good quorum-sensing potential indicates that these can suppress microbial resistance severity infections.