Method Validation and Determination of Total Antioxidants, Polyphenols, Flavonoids, and Vitamin C Contents in the Yemeni Grapes. jast [Internet]. 2025 Apr. 30 [cited 2026 Jun. 16];3(2):740-8. Available from: https://journals.su.edu.ye/index.php/jast/article/view/1499