Bioactives from Crude Rice Bran Oils Extracted Using Green Technology

Area of Science:

• Food Science and Technology
• Green Chemistry
• Nutraceuticals

Background:

• Rice bran oil (RBO) is rich in nutraceuticals like gamma-oryzanol, phytosterols, and policosanols, contributing to its cholesterol-lowering benefits.
• Growing global warming concerns drive interest in sustainable, green extraction technologies for RBO.

Purpose of the Study:

• To compare the nutraceutical composition and antioxidant properties of RBO extracted from white and red rice bran.
• To evaluate three green extraction technologies against conventional hexane extraction.

Main Methods:

• Extraction of RBO from white and red rice bran using conventional hexane, subcritical liquefied dimethyl ether, and supercritical CO2 extraction.
• Quantification of gamma-oryzanol, phytosterols, and policosanols.
• Assessment of total phenolic content and antioxidant activities.

Main Results:

• Subcritical liquefied dimethyl ether extraction yielded high oil percentages, comparable to hexane extraction, and superior to supercritical CO2.
• This green method also yielded the highest total phenolic content and antioxidant activities.
• Red rice bran, particularly when extracted with subcritical dimethyl ether, showed the highest total phytosterol content.

Conclusions:

• Subcritical liquefied dimethyl ether extraction is an effective green technology for producing RBO with high nutraceutical content and antioxidant properties.
• Red rice bran is a superior source for phytosterols compared to white rice bran.
• Green extraction methods offer a sustainable alternative for obtaining valuable RBO nutraceuticals.