Optimization of Inositol Extraction from Japanese Rice Bran and Its Potential Application in Inhibiting Calcium Oxalate Crystallization for Urolithiasis Prevention

Rice bran is considered as one of the most prominent byproducts of the rice milling industry. It constitutes various bioactive compounds like myo-inositol. This study focuses on extracting myo-inositol from Japanese rice bran (Oryza sativa Japonica Group) using an eco-friendly, optimized method. The extraction was first optimized through the response surface methodology, yielding maximum inositol after 2 h at 80 °C with a solute concentration of 1:10. Microwave-assisted extraction further improved efficiency, achieving a significantly higher yield in just 5 min. The inositol-rich extract inhibited calcium oxalate crystallization, proving effective against urolithiasis by converting calcium oxalate monohydrate to the more easily excretable dihydrate form. These findings suggest the potential for developing cost-effective, eco-friendly formulations and nutraceuticals to combat urolithiasis.