Evaluation of antimicrobial and MMP inhibitory properties of onion peel extracts

MMP inhibition and antimicrobial properties are important in many applications in the field of Conservative Dentistry and Endodontics to preserve the quality of dentin in a bond or to prevent reinfection and failure in root canal treated teeth. Many natural products are being explored for the above properties as they are safer compared to synthetic ones. Aim: Present study aims to check for the antibacterial action of a small onion and large onion peel extract against Enterococcus faecalis(E. faecalis),Streptococcus mutans(S. mutans) , and also MMP inhibition. Materials and methods: Antibacterial efficacy of small onion and large onion peel extract was evaluated by determining MIC, MBC, and zone of inhibition against E. faecalis, and S. mutans biofilm. UV-visible spectrophotometric analysis was performed for the identification of phytoconstituents present in ethanolic extract of small and large onion peel extract. Computational Drug Designing and Characterization of Phytocompounds present in the extract was determined by Gas Chromatography-Mass Spectrometry (GC- MS) Profiling. Molecular docking (in-silico) was performed using AutoDock open source free software by using editing options and other default parameters. Results: Both Onion peel extracts had good antibacterial properties against both S mutans and E faecalis as determined by their MIC, MBC, and ZOI in this study. They were found to have many phytochemicals notably, β-sitosterol and quercetin. Small onion peel extract had greater quantities of β-sitosterol and quercetin than large onion peel extract. Molecular docking for enzymatic inhibition using in-silico docking study found that both the extracts have MMP2 & 9 inhibition equivalent to control Galardin.