Radho Al Kausar, Shania Garcia, Zakia Rahmah, Ratri Mauluti Larasati, Devi Nur Anisa, Diah Astika Winahyu, Annisaa Siti Zulaicha, Andi Setiawan
Strategies to mitigate oxidative stress through natural antioxidants necessitate innovative approaches, particularly by exploring underutilized bioactive sources and optimizing sustainable extraction technologies. Morinda citrifolia L. (noni) leaves are a notable source of bioactive phytochemicals, with well-documented antioxidant activity. This study aimed to develop and evaluate capsule formulations from noni leaves using microwave-assisted extraction (MAE), a green, efficient extraction technique. Extraction using 70% ethanol yielded a 15.62% dry extract, demonstrating superior extraction efficiency compared with conventional methods. Capsule formulations (F0–F3) were prepared with pharmaceutical-grade excipients and assessed for physicochemical properties, including moisture content, flowability, and weight uniformity, all of which met acceptable pharmacopeial limits for a preliminary capsule quality evaluation. Fourier transform infrared spectroscopy confirmed the retention of CdbndO and aromatic C–H vibrations characteristic of phenolic and flavonoid structures. In contrast, HPLC analysis identified rutin (93.6 mg/100 g dry weight) as the predominant flavonoid, followed by quercetin and kaempferol. Scanning electron microscopy revealed that encapsulation transformed the extract's initially irregular and aggregated particles into smoother, more uniform matrix structures, indicating effective microstructural stabilization of the phytochemicals. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay demonstrated potent antioxidant activity, with IC₅₀ values of 4.95 ppm for the extract and below 15 ppm for the capsule formulations, reflecting powerful antioxidant capacity. Overall, the enhanced bioactive recovery, structural stabilization, and potent antioxidant activity of MAE-derived noni leaf capsules underscore their potential as antioxidant-rich formulations for further nutraceutical research and development. © 2026 Elsevier B.V.
Department of Chemistry, Lampung University, Lampung, Indonesia; Department of Physics, Gadjah Mada University, Yogyakarta, Indonesia; Department of Pharmaceutical and Food Analysis, Malahayati University, Lampung, Indonesia; Department of Physiology, Biochemistry and Biomolecular, Lampung University, Lampung, Indonesia; Department of Cosmetic Engineering, Sumatera Institute of Technology, Indonesia