Gamma-oryzanol as an example of a complex of phytosterol esters and ferulic acid with broad biological activity

Plants are natural laboratories producing a cornucopia of secondary metabolites of huge therapeutic potential. The oil extracted from rice bran, a by-product of brown rice processing, is abundant in valuable bioactive substances. One of its main ingredients is gamma-oryzanol that is a mixture of phytosterol esters and ferulic acid. These compounds exert a wide range of biological activities closely correlated with their chemical properties. Their hypocholesterolemic and antioxidant abilities are crucial for improving the physiology and condition of the human body. For these reasons, there has been a clear increase in the number of studies investigating the use of gamma-oryzanol in the treatment of many chronic diseases, and it is even tested as a promising non-pharmacological therapeutic agent in the treatment of COVID-19 in overweight people. This paper describes the chemical structure and activity of gamma-oryzanol based on biological activity of phytosterol esters and ferulic acid. It also discusses the effects of gamma-oryzanol on some physiological processes in the human and animal organisms.