Supercritical Fluid Extraction of Nutraceuticals from Rice Bran

Supercritical fluid extraction (SFE) has emerged as a sustainable and efficient approach for isolating high-value nutraceutical compounds from rice bran, a by-product of rice milling that is rich in lipophilic bioactives. In SFE, carbon dioxide is raised beyond its critical temperature and pressure to form a dense fluid with gas-like diffusivity and liquid-like solvating power, enabling selective extraction of phytochemicals without the use of hazardous organic solvents. Process parameters such as pressure, temperature and co-solvent concentration can be finely tuned to optimise yield and purity of rice bran oil fractions enriched in tocopherols, tocotrienols, γ-oryzanol and phytosterols. Compared with conventional solvent extraction, SFE affords superior preservation of antioxidant capacity, minimises thermal degradation and reduces post-extraction refining steps. Owing to its low environmental footprint and scalability, SFE has attracted growing interest in both academic and industrial settings for the production of functional food ingredients, dietary supplements and cosmeceuticals. Recent advances have focused on integration of pre-treatment techniques, such as particle size reduction and enzymatic hydrolysis, and on hybrid extraction schemes combining SFE with membrane separation or adsorption to further enhance selectivity. Global significance is underscored by demand for green manufacturing and value-addition to agricultural by-products, positioning SFE of rice bran nutraceuticals as a frontier in sustainable bioprocessing.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Supercritical Fluid Extraction of Nutraceuticals from Rice Bran publication trend

The graph below shows the total number of articles in supercritical fluid extraction of nutraceuticals from rice bran across all publications each year (not limited to Nature Index journals).

Technical terms

Supercritical fluid extraction (SFE): Utilisation of a fluid above its critical temperature and pressure to selectively dissolve and recover target compounds from solid matrices.

Supercritical carbon dioxide (scCO₂): Carbon dioxide maintained above 31.1 °C and 73.8 bar, employed as a non-toxic solvent with adjustable density and solvating power.

γ-Oryzanol: A mixture of ferulate esters of sterols and triterpenic alcohols abundant in rice bran oil, known for antioxidative and lipid-modulating properties.

Tocopherols and tocotrienols: Isoforms of vitamin E present in rice bran oil, acting as potent free-radical scavengers and membrane stabilisers.

Phytosterols: Plant-derived sterols structurally similar to cholesterol, which contribute to cardiovascular health by inhibiting intestinal cholesterol absorption.

References

1. Rice Bran Oil: Emerging Trends in Extraction, Health Benefit, and Its Industrial Application. Rice Science (2021).
2. A short review of green extraction technologies for rice bran oil. Biomass Conversion and Biorefinery (2020).
3. Stability of rice bran oil extracted by SFE and soxhlet methods during accelerated shelf-life storage. Grasas y Aceites (2014).