Binary Solvent Extraction of Tocols, γ-Oryzanol, and Ferulic Acid from Rice Bran Using Alkaline Treatment Combined with Ultrasonication.

Alkaline treatment (Alk) combined with ultrasound-assisted extraction (UAE) (Alk+UAE) was examined as a means of extracting tocols and γ-oryzanol from rice bran into an organic phase while simultaneously recovering ferulic acid into an aqueous phase. The tocols and γ-oryzanol/ferulic acid yields were determined using high-performance liquid chromatography with fluorescence and UV detection. The effects of extraction conditions were evaluated by varying the Alk treatment temperature and extraction duration. The maximum yields of tocols and γ-oryzanol were obtained at 25 °C over a time span of 30 min. When the temperature was increased to 80 °C, the yield of ferulic acid increased dramatically, whereas the recovery of γ-oryzanol slightly decreased. Employing the Alk+UAE procedure, the recovered concentrations of tocols, γ-oryzanol, and ferulic acid were in the ranges of 146-518, 1591-3629, and 352-970 µg/g, respectively. These results are in good agreement with those reported for rice bran samples from Thailand.

Semi-preparative HPLC separation followed by HPLC/UV and tandem mass spectrometric analysis of phorbol esters in Jatropha seed.

Phorbol esters (PEs) are well known as the main toxic compounds in Jatropha curcas Linnaeus (JCL), the seed oil of which has been considered as a major feedstock for the production of biodiesel. In the present study, we investigated a series of PEs extracted from JCL seed kernels with methanol (MeOH), and identified more than seven components contained in the PEs. The isolation of main five components of a series of PEs was revised using a semi-preparative reversed phase HPLC analysis of ODS-3 column. The five peaks of components were successfully isolated, and peaks of J2, J3, J5, and J7 were assigned to be Jatropha factors C1, C2, C3, and C4/5, but J6 was a mixture of Jatropha factor C6 and its isomer based on the data of UV and LC-MS/MS, and J2 was identified using 1H NMR analysis. By characterization using LC-MS/MS analysis, all components of a series of PEs were elucidated to be the 12-deoxy-16-hydroxyphorbol esters composed of isomeric form of dicarboxylic groups with same m/z value of 380.