Abstract: By high performance liquid chromatography (HPLC), we analyzed the difference in total γ-oryzanol content in brown rice from five different rice-producing regions (Fangzheng, Xiangshui, Chahayang, Wuchang, and Jiansanjiang) in Heilongjiang province, and we determined the correlation between ferulic acid ester monomers in rice. The results showed that the total content of γ-oryzanol changed from 10.88 to 33.53 mg/100 g, with cycloartenol ferulate, 24-methylenecycloartanyl ferulate being the most abundant, followed by campesterol ferulate and β-sitosterol ferulate. In addition, the γ-oryzanol content varied at different maturity stages. The total content of γ-oryzanol significantly varied under natural conditions. The average content of γ-oryzanol in brown rice from Wuchang was the highest, (21.48 ± 5.04) mg/100 g, and the lowest value (16.56 ± 6.29) mg/100 g was found in brown rice from Xiangshui. There was a linear relationship between the ferulic acid ester monomers.

Key words: brown rice; γ-oryzanol; ferulic acid ester; high performance liquid chromatography