Quantitative analyses of individual γ-Oryzanol (Steryl Ferulates) in conventional and organic brown rice (Oryza sativa L.)

• Published in: Journal of cereal science Vol. 55; no. 3; pp. 337 - 343
• Main Authors: Cho, Jeong-Yong, Lee, Hyoung Jae, Kim, Gee An, Kim, Gwi Deok, Lee, You Seok, Shin, Soo Cheol, Park, Keun-Hyung, Moon, Jae-Hak
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-05-2012; Elsevier
• Subjects: Biological and medical sciences; Brown rice; Cereal and baking product industries; Food industries; Fundamental and applied biological sciences. Psychology; ODS-HPLC; Steryl ferulate; γ–Oryzanol; γ–Oryzanol; Steryl ferulate; ODS-HPLC; Brown rice; Monocotyledones; HPLC chromatography; Oryza sativa; Gramineae; Angiospermae; Cereal; Spermatophyta; γ―Oryzanol; Quantitative analysis; Rice
• ISSN: 0733-5210; 1095-9963
• DOI: 10.1016/j.jcs.2012.01.005

γ-Oryzanol (steryl ferulates; SF) has been shown to be a major bioactive compound in rice. To determine the content of individual γ-oryzanols in brown rice by high performance liquid chromatography (HPLC), purification of individual SF for use as an external standard is required. Four main SF were isolated from a commercial γ-oryzanol mixture and identified as cycloartenyl ferulate (1), 24-methylenecycloartanyl ferulate (2), campesteryl ferulate (3), and sitosteryl ferulate (4) based on mass spectrometry and nuclear magnetic resonance spectroscopic data. The SF contents between conventional and organic brown rice were qualitatively determined by HPLC using SF isolated from a commercial γ-oryzanol mixture as the external standard. The total γ-oryzanol content (mg/100 g) in organic brown rice (65.6 ± 2.7) was slightly higher (P < 0.05) than that found in conventional brown rice (60.2 ± 1.8). The content (mg/100 g) of 1 (21.2 ± 0.9) and 4 (9.8 ± 0.4) in organic brown rice was higher (P < 0.05) than that observed in conventional brown rice (1, 18.2 ± 1.1; 4, 8.5 ± 0.3). However, the content of 2 and 3 in the conventional and organic brown rice samples did not differ significantly. These results indicate that the cultivation methods do significantly alter the γ-oryzanol content for conventional and organic brown rice.
► A novel HPLC method to analyze individual γ-oryzanol was established. ► The γ-oryzanol content in organic rice was higher than that in conventional rice. ► This method holds great promise for use in studying a wide range of γ-oryzanol.