Composition, industrial processing and applications of rice bran γ-oryzanol

Nanofiltration process for the nutritional enrichment and refining of rice bran oil

The value-added γ-oryzanol was purified in one step from crude rice bran oil (RBO) using a preparative hydrostatic countercurrent chromatography (hydrostatic CCC) method, operating in the dual mode. The fractionation was performed using a non-aqueous biphasic solvent system consisting of heptane-acetonitrile-butanol (1.8:1.4:0.7, v/v/v), leading rapidly to the target compounds. Transfer of the analytical CCC method to large-scale isolation was also carried out yielding a high quantity-high purity fraction of γ-oryzanol. In addition, a fraction of hydroxylated triterpene alcohol ferulates (polar γ-oryzanol) was clearly separated and obtained. Furthermore, a fast HPLC-APCI(±)-HRMS method was developed and applied for the identification of γ-oryzanol as well as the polar γ-oryzanol in RBO and the resulting fractions. The purity of γ-oryzanol fraction was estimated as 97% based on HPLC-APCI-HRMS analysis.

One‐step isolation of γ‐oryzanol from rice bran oil by non‐aqueous hydrostatic countercurrent chromatography

Preparative separation of triterpene alcohol ferulates from rice bran oil using a high performance counter-current chromatography.

Rice (Oryza sativa seeds – Poaceae) is considered one of the most important grains, as it is consumed by the half of the world population. Various by-products of the rice industry, such as rice bran and the rice bran oil (RBO), have recently attracted much attention from both academia and industry due to their high content of high added-value phytochemicals such as tocopherols/tocotrienols, carotenoids, and γ-oryzanol, of nutritional, pharmaceutical, and cosmetic interest. In particular, γ-oryzanol, a mixture of triterpene alcohol and phytosterol ferulates, is characterized by a wide spectrum of health-beneficial effects, including anticarginogenic, anti-inflammatory, antihyperlipidemic, and neuroprotective, which are mainly attributed to its significant antioxidant capacity. This chapter presents the chemical characteristics of γ-oryzanol components, their classification and biosynthesis, as well as an overview regarding the traditional and modern methods for γ-oryzanol extraction, isolation, analysis, and identification. A summary regarding its biological profile and applications is also provided.

γ-Oryzanol: An Attractive Bioactive Component from Rice Bran

γ‐Oryzanol is considered to be an important fraction in rice bran oil. Due to the low concentration levels (1–3%) of γ‐oryzanol in crude rice bran oil (CRBO), isolation and purification would be necessary before practical usage. This study developed an efficient and easy‐to‐scale‐up chromatographic separation method for the production of γ‐oryzanol. First, the CRBO was prepared using a Soxhlet extractor operated under an optimal extraction condition (using 130 mL of hexane for 2 hr per 15 g rice bran). The extraction yield was 16–18% (w/w) and the purity of γ‐oryzanol was 2.4–3.0% (w/w). Then, γ‐oryzanol in the CRBO was purified by preparative elution chromatography under the normal phase mode. Column operation was optimized by using a silica gel column packed with small particles (12 µm) and operated by a three‐step gradient elution mode, where the mobile phase composition of hexane/ethyl acetate was from 90:10 or 85:15 to 50:50 v/v to pure ethyl acetate. The injection amount was increased as la...

Chih‐Wei Chang

Papers

Preparative separation of γ-oryzanol from rice bran oil by silica gel column chromatography