**Abstract**

This chapter summarizes the entire literature available on the nutritional value and diverse therapeutic potentials Gamma-oryzanol, a nutraceutical obtained from rice brain oil, composed of a mixture of *γ* - oryzanol, a mixture of ferulic acid esters of phytosterols and triterpenoids, cycloartenyl ferulate, 24-methylenecycloartanyl ferulate, and campesteryl ferulate. In brief, the review covers the aspects such as the antioxidant mechanisms, effects on immune system, lipid disorders, diabetes, obesity and inflammation with the details of preclinical experiments, models and observations. Among the other highlights are the hepatoprotective, neuroprotective role in various neurological disorders such as Alzheimer's, anxiety, Parkinson's disease and wound healing effects. An overview of the sources, chemistry, physicochemical properties, pharmacokinetics and toxicity studies are also included.

**Keywords:** Gamma oryzanol, rice bran oil, pharmacological activities, nutraceutical, organoprotective

#### **1. Introduction**

Rice is a staple food in many countries around the world. Milling of rice gives an 8% byproduct, rice bran [1]. Crude rice bran oil is obtained by different methods. According to Godber and Xu the most efficient way to extract rice bran oil is superficial fluid extraction technology [2]. Rice bran oil contains the naturally occurring nutritive and antioxidant phytochemical, *γ*- oryzanol [1]. It is one of the phytochemicals present in high amounts in rice bran [3].

The molecular formula of *γ*- oryzanol is C40H58O4 and its melting point is 137.5-138.5°C. It is a white crystalline powder. *γ*- oryzanol is insoluble in water. However, it is slightly soluble in diethyl ether and n-heptane. Previously, *γ*-oryzanol was thought to be a single compound [1]. It was later discovered that *γ*- oryzanol is a mixture of phytosterylferulates of ferulic acid esterified with phytosterols including sterols (campesterol, sitosterol, and stigmasterol) and triterpene alcohols (cycloartenol and 24- methylenecycloartenol) [3]. The structure of gamma oryzanol is shown in **Figure 1**.

**Figure 1.** *Structure of gamma Oryzanol.*
