Farag M.A.Ali S.E.Hodaya R.H.El-Seedi H.R.Sultani H.N.Laub A.Eissa T.F.Abou-Zaid F.O.F.Wessjohann L.A.Pharmacognosy DepartmentCollege of PharmacyCairo UniversityKasr el Aini St.CairoEgypt; Department of Pharmaceutical BiologyFaculty of Pharmacy and BiotechnologyGerman University in CairoP.B. 11835CairoEgypt; Plant Production DepartmentDesert Research CenterP.B. 11714CairoEgypt; Division of PharmacognosyDepartment of Medicinal ChemistryUppsala UniversityBox 574UppsalaSE-75 123Sweden; Department of ChemistryFaculty of ScienceEl-Menoufia UniversityShebin El-Kom32512Egypt; Leibniz Institute of Plant BiochemistryDept. Bioorganic ChemistryWeinberg 3Halle (Saale)D-06120Germany; Pharmacognosy DepartmentCollege of PharmacyModern Science and Arts UniversityP.B. 12566CairoEgypt2020-01-092020-01-09201714203049https://doi.org/10.3390/molecules22050761PubMed ID 28481316https://t.ly/ge8WjScopusPlants of the Allium genus produce sulphur compounds that give them a characteristic (alliaceous) flavour and mediate for their medicinal use. In this study, the chemical composition and antimicrobial properties of Allium cepa red cv. and A. sativum in the context of three different drying processes were assessed using metabolomics. Bulbs were dried using either microwave, air drying, or freeze drying and further subjected to chemical analysis of their composition of volatile and non-volatile metabolites. Volatiles were collected using solid phase micro-extraction (SPME) coupled to gas chromatography-mass spectrometry (GC/MS) with 42 identified volatiles including 30 sulphur compounds, four nitriles, three aromatics, and three esters. Profiling of the polar non-volatile metabolites via ultra-performance liquid chromatography coupled to high resolution MS (UPLC/MS) annotated 51 metabolites including dipeptides, flavonoids, phenolic acids, and fatty acids. Major peaks in GC/MS or UPLC/MS contributing to the discrimination between A. sativum and A. cepa red cv. were assigned to sulphur compounds and flavonoids. Whereas sulphur conjugates amounted to the major forms in A. sativum, flavonoids predominated in the chemical composition of A. cepa red cv. With regard to drying impact on Allium metabolites, notable and clear separations among specimens were revealed using principal component analysis (PCA). The PCA scores plot of the UPLC/MS dataset showed closer metabolite composition of microwave dried specimens to freeze dried ones, and distant from air dried bulbs, observed in both A. cepa and A. sativum. Compared to GC/MS, the UPLC/MS derived PCA model was more consistent and better in assessing the impact of drying on Allium metabolism. A phthalate derivative was found exclusively in a commercial garlic preparation via GC/MS, of yet unknown origin. The freeze dried samples of both Allium species exhibited stronger antimicrobial activities compared to dried specimens with A. sativum being in general more active than A. cepa red cv. � 2017 by the authors.EnglishOctober University for Modern Sciences and ArtsUniversity for Modern Sciences and ArtsMSA Universityجامعة أكتوبر للعلوم الحديثة والآدابAnti-microbialDryingFlavonoidsGarlicMetabolomicsOnionOrganosulphurantiinfective agentflavonoidsulfur derivativechemistrycomparative studygarlicmass spectrometrymetabolismmetabolomicsonionproceduresAnti-Infective AgentsFlavonoidsGarlicMass SpectrometryMetabolomicsOnionsSulfur CompoundsArticlehttps://doi.org/10.3390/molecules22050761PubMed ID 28481316