Planta Med 2016; 82(S 01): S1-S381
DOI: 10.1055/s-0036-1596853
Abstracts
Georg Thieme Verlag KG Stuttgart · New York

Implementation of supercritical fluid chromatography for the isolation of new polar γ-oryzanol from rice bran oil

Authors

  • M Spiliopoulou

    1   Laboratory of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, University of Athens, Panepistimioupoli Zografou, 15771 Athens, Greece

  • V Brieudes

    1   Laboratory of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, University of Athens, Panepistimioupoli Zografou, 15771 Athens, Greece

  • A Angelis

    1   Laboratory of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, University of Athens, Panepistimioupoli Zografou, 15771 Athens, Greece

  • M Halabalaki

    1   Laboratory of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, University of Athens, Panepistimioupoli Zografou, 15771 Athens, Greece

  • LA Skaltsounis

    1   Laboratory of Pharmacognosy and Natural Products Chemistry, Department of Pharmacy, University of Athens, Panepistimioupoli Zografou, 15771 Athens, Greece
Further Information

Publication History

Publication Date:
14 December 2016 (online)

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Rice Bran Oil (RBO) is commonly used cooking oil in Asia, which is obtained from bran, a by-product of the rice milling process. In comparison to other vegetable oils, RBO contains higher amount of γ-oryzanol (γOR). γOR is a mixture of more than 20 ferulic acid esters of phytosterols & triterpene alcohols and has been reported to display an important pharmacological profile, i.e. antidiabetic, antihyperlipidemic and anti-inflammatory activity [1]. Recently, a new chemical entity similar to γOR, called “polar” γ-oryzanol (PγOR) was identified in RBO [2].

The present work aims at the isolation and characterization new PγOR components present in rice bran. For that purpose, rice bran EtOAc extracts have been subjected to hydrostatic CCC for fractionation. Collected fractions were then analyzed by UHPLC-APCI(-)-HRMS clearly revealing complex mixtures of hydroxylated triterpene alcohol and sterol ferulates. Furthermore, a method using Supercritical Fluid Chromatography (SFC) with CO2 as mobile phase and methanol as co-solvent coupled to single quadrupole mass spectrometer was developed and implemented at the preparative scale toward the isolation of PγOR components. Finally, UHPLC-APCI(-)-HRMS and direct infusion-HRMS were employed to structurally characterize the purified compounds. Although MSn data did not allow unambiguous determination, a characteristic fragmentation pattern of this family of compounds was observed at the MS2 and MS3 levels. NMR experiments were then conducted (1H NMR, HSQC-DEPT and HMBC) to provide complementary data for completing structural elucidation, especially of isobaric compounds (e.g. cycloart-25-ene-3β,24-diol-3β-trans-ferulate and cycloart-23-ene-3β,24-diol-3β-trans-ferulate). To conclude, the present work demonstrated feasibility for the isolation of new low-polarity bioactive PγOR components from rice bran using modern “green” technologies such as SFC.

Acknowledgements: This study was supported by the Commission of the European Community, Framework Program 7, (PEOPLE- Industry- Academia Partnerships and Pathways) Grant agreement no. 286287 NATPROTEC. The authors also acknowledge the rice processing company EV. GE. PISTIOLAS S.A. (Agrinio, Greece) for providing rice bran samples.

Keywords: Supercritical fluid chromatography, polar γ-oryzanol, Rice Bran Oil, HRMS, NMR.

References:

[1] Lemus C, Angelis A, Halabalaki M, Skaltsounis AL, in: R.R.W.R.P. Zibadi (Ed.), Wheat and Rice in Disease Prevention and Health, Academic Press, San Diego, 2014; pp.409 – 430

[2] Angelis A, Urbain A, Halabalaki M, Aligiannis N, Skaltsounis AL. One-step isolation of γ-oryzanol from rice bran oil by non-aqueous hydrostatic countercurrent chromatography. J Sep Science 2011; 34: 2528 – 2537


No conflict of interest has been declared by the author(s).