_1700052870 20231115125430000 Editor editor.jddt@gmail.com Universal Journal of Pharmaceutical Research Universal Journal of Pharmaceutical Research Univ J Pharm Res 2456-8058 2831-5235 11 15 2023 Ahmad Najib https://orcid.org/0000-0001-5055-7964 Virsa Handayani https://orcid.org/0000-0003-0379-3571 Muhammad Rizki Jaelani https://orcid.org/0009-0005-1241-0503 Aim and objective: In this study, the free radical scavenging of tectoquinone compound isolated from leaf of Syzygium oblanceolatum (C.B. Rob.) Merr was investigated by assessing their capacity to scavenge free radicals using the DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay. Methods: The quantitative assessment of antioxidant activity was conducted using a UV-Vis spectrophotometric approach, with measurements taken at a wavelength of 516 nm. Results: The IC50 value, representing the concentration required to inhibit 50% of the DPPH radicals, was determined to be 66.362 μg/mL, indicating a moderate free radical-scavenging activity. Conclusion: These findings suggest that tectoquinone compounds possess a discernible ability to against free radical, though further research may be necessary to optimize their potential applications in health and medicine.                         Peer Review History: Received: 21 August 2023; Revised: 18 September; Accepted: 9 October, Available online: 15 November 2023 Academic Editor: Dr. Ali Abdullah Al-yahawi, Al-Razi university, Department of Pharmacy, Yemen, alyahawipharm@yahoo.com Received file:                             Reviewer's Comments: Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. Bilge Ahsen KARA, Ankara Gazi Mustafa Kemal Hospital, Turkey, ahsndkyc@gmail.com Dr. Sangeetha Arullappan, Universiti Tunku Abdul Rahman, Malaysia, sangeetha@utar.edu.my 11 15 2023 http://creativecommons.org/licenses/by-nc/4.0 10.22270/ujpr.v8i5.1003 https://ujpr.org/index.php/journal/article/view/1003 https://ujpr.org/index.php/journal/article/download/1003/1477 https://ujpr.org/index.php/journal/article/download/1003/1477 https://ujpr.org/index.php/journal/article/download/1003/1494 https://ujpr.org/index.php/journal/article/download/1003/1500