en ترکیبات طبیعی Natural products پژوهشي Original Research <strong>Background</strong>: Essential oil (EO) of Syzygium aromaticum is usually used for medicinal purposes. In most cases, it is kept for a long duration.&nbsp;<br> <strong>Objectives</strong>: The work aimed at examining how the duration of storage of the EO affects its medicinal quality of the essential oil.&nbsp;<br> <strong>Methods</strong>: The EO of S. aromaticum was extracted by hydrodistillation. The extracted EO was kept in a cupboard in amber bottles at room temperature for 4, 183, and 365 days. Chemical components of the EOs were determined by gas chromatography mass spectroscopy (GC-MS). The antioxidant activity was determined by using the 2,2-diphenyl-1-picryl-hydrazyl (DPPH), 2,2-azobis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and ferric reducing antioxidant power (FRAP) assays. Dopamine and butyrylcholinesterase (BCHE) assays were used to assess the anti-hypertensive activity. The anti-diabetic tendencies were evaluated with the &alpha;-glucosidase and &alpha;-amylase assays. Albumin denaturation and protease were used to estimate the anti-inflammatory activity.&nbsp;<br> <strong>Results</strong>: The results indicate that the EO shows a color change from light yellow in 4 and 183 days of storage to dark brown after 365 days. The results of the GC-MS show a higher value of eugenol in the EO stored for 183 and 365 days (93.15% and 93.46%, respectively). It also shows the presence of eugenol acetate (17.05%) in the EO stored for 4 days, but it was absent in 183 and 365 days of storage. The EO stored for 4 days had a higher inhibition of antioxidant, anti-inflammatory, anti-hypertensive, and anti-diabetic parameters tested.<br> <strong>Conclusion</strong>: The results indicate that the higher the period of storage of the essential oil, the less medicinal potency it possesses. Syzygium aromaticum, Essential oil, Antioxidant, Anti-inflammatory, Anti-hypertensive, Antidiabetic 369 384 http://pbr.mazums.ac.ir/browse.php?a_code=A-10-1428-1&slc_lang=en&sid=1 Abayomi Gideon Adeyemo adeyemoabayomi0205@gmail.com 100319475328460011841 0009-0001-7703-5194 Yes Department of Pure and Applied Chemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria. Shola Hezekiah Awojide shola.awojide@uniosun.edu.ng 100319475328460011842 100319475328460011842 No Department of Pure and Applied Chemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria. Alilat Ololade Tiamiyu ololadetiamiyu19@gmail.com 100319475328460011843 100319475328460011843 No Department of Pure and Applied Chemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria. Adebanjo Jacob Anifowose adebanjo.anifowose@uniosun.edu.ng 100319475328460011844 100319475328460011844 No Anifowose Adedayo Olubunmi Adeboye adedayo.adeboye@uniosun.edu.ng 100319475328460011845 100319475328460011845 No Department of Food Science and Technology, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria. Ezekiel Olumide Fadunmade o.fadunmade@learninganddevelopmentbureau.org.uk 100319475328460011846 100319475328460011846 No Learning and Development Bureau, Chatham, United Kingdom. Oluwatumininu Abosede Mutiu mutiuoluwatumininu@gmail.com 100319475328460011847 100319475328460011847 No Industrial Chemistry Program, Bowen University, Iwo, Nigeria. Yemisi Elizabeth Asibor yemisi.asibor@uniosun.edu.ng 100319475328460011848 100319475328460011848 No Department of Pure and Applied Chemistry, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Nigeria.