Development and characterization of surface solid dispersion Moringa oleifera leaf extract-microcrystalline cellulose by co-grinding method

Context: Moringa oleifera leaf extract is rich in flavonoid compounds and potential antioxidant sources. However, the development of M. oleifera leaf extract into an herbal product is limited by challenges such as inconsistent quality, hygroscopicity, and poor solubility. Surface solid dispersion (SSD) is a versatile method to enhance both the physical properties and solubility of such extracts. Aims: To enhance the physical and solubility properties of M. oleifera leaf extract using SSD with microcrystalline cellulose as a carrier. Methods: SSD was prepared using a co-grinding method with extract-to-carrier ratios of 1:2 and 1:4. Results: This study revealed that the SSD effectively absorbed the extract onto the surface of microcrystalline cellulose. Hence, the SSD powder exhibited improved moisture content and flowability. Thermal and crystallinity analyses revealed a reduction in crystal lattice regularity compared to the pure extract, as evidenced by decreased enthalpy and diminished peak intensity. The total flavonoid content of SSD 1:2 was 14.70 ± 0.35 mg QE/g, whereas SSD 1:4 was 7.00 ± 0.07 mg QE/g. Flavonoid solubility compound from SSD 1:2 was 62.26 ± 0.62 µg/mL, while the solubility of SSD 1:4 was 63.58 ± 0.62 µg/mL. The solubility of the flavonoid compound from SSD preparation increased about 1.16-fold compared to the physical mixture. Conclusions: SSD preparation of M. oleifera leaf extract improves its physical and chemical properties, making it more suitable for formulation.