Optimisation of an ultrasound-assisted extraction method for the simultaneous determination of phenolics in rice grains

Widiastuti Setyaningsih; Irfan E Saputro; Ceferino A Carrera; Miguel Palma

doi:10.1016/j.foodchem.2019.02.107

Optimisation of an ultrasound-assisted extraction method for the simultaneous determination of phenolics in rice grains

Food Chem. 2019 Aug 1:288:221-227. doi: 10.1016/j.foodchem.2019.02.107. Epub 2019 Mar 2.

Authors

Widiastuti Setyaningsih¹, Irfan E Saputro², Ceferino A Carrera³, Miguel Palma⁴

Affiliations

¹ Department of Food and Agricultural Product Technology, Faculty of Agricultural Technology, Gadjah Mada University, Jalan Flora, Bulaksumur, Sleman, 55281 Yogyakarta, Indonesia. Electronic address: widiastuti.setyaningsih@ugm.ac.id.
² Department of Analytical Chemistry, Faculty of Sciences, IVAGRO, University of Cadiz, Campus de Excelencia Internacional Agroalimentario (CeiA3), Campus del Rio San Pedro, 11510, Puerto Real, Cadiz, Spain.
³ Department of Analytical Chemistry, Faculty of Sciences, IVAGRO, University of Cadiz, Campus de Excelencia Internacional Agroalimentario (CeiA3), Campus del Rio San Pedro, 11510, Puerto Real, Cadiz, Spain. Electronic address: ceferino.carrera@uca.es.
⁴ Department of Analytical Chemistry, Faculty of Sciences, IVAGRO, University of Cadiz, Campus de Excelencia Internacional Agroalimentario (CeiA3), Campus del Rio San Pedro, 11510, Puerto Real, Cadiz, Spain. Electronic address: miguel.palma@uca.es.

PMID: 30902286
DOI: 10.1016/j.foodchem.2019.02.107

Abstract

Fifteen phenolic compounds were determined in rice grains by ultrasound assisted extraction and ultra-performance liquid chromatography with photodiode array detection. Primarily, an UAE method has been developed and validated for the extraction of phenolics from rice grains. For the optimization, a Box-Behnken Design based on six factors including extraction temperature (10-70 °C), solvent composition (0-50% methanol in water), cycle (0.2-0.7 s^-1), ultrasound amplitude (30-70%), and solvent to sample ratio (2.5:1 to 5:1) was employed. Multi-response optimization (MRO) was performed to develop a simultaneous extraction method of 15 phenolics. The optimal UAE conditions were: extraction temperature 45 °C, time 25 min, cycle 0.4 s^-1, ultrasound amplitude 47%, solvent composition 80% methanol in water at pH 4.25, and sample to solvent ratio 1:5. Linearity, LODs, LOQs, precision and recovery were determined. In addition, the method was successfully applied to analyse a number of rice samples with different varieties.

Keywords: Phenolics; Rice grains; UPLC-PDA; Ultrasound-Assisted extraction.

MeSH terms

Chromatography, High Pressure Liquid
Limit of Detection
Oryza / chemistry*
Phenols / analysis*
Phenols / isolation & purification
Reference Standards
Solvents / chemistry
Sonication / methods*

Substances

Phenols
Solvents