2008-Optimisation of ultrasound-assisted extraction from wh

FoodChemistry

FoodChemistry106(2008)804–810

/locate/foodchem

Analytical,NutritionalandClinicalMethods

Optimisationofultrasound-assistedextractionofphenolic

compoundsfromwheatbran

JingWanga,*,BaoguoSuna,YanpingCaoa,YuanTiana,XuehongLib

a

CollegeofChemistryandEnvironmentEngineering,BeijingTechnologyandBusinessUniversity,11FuchengRoad,Beijing100037,PRChina

b

DepartmentofFoodandBioengineering,ZhengzhouUniversityofLightIndustry,5DongfengRoad,Zhengzhou450002,PRChina

Received18March2007;receivedinrevisedform2May2007;accepted27June2007

Abstract

Wheatbran,animportantby-productofthecerealindustry,isrichinpotentiallyhealth-promotingphenoliccompounds.Inthispaper,thephenolic

compoundsfromwheatbranwereextractedbyultrasound-assistedextractiontechnology.Theexperimentswerecar-riedoutaccordingtoa velevel,threevariablecentralcompositerotatabledesign(CCRD),andthebestpossiblecombinationofsolventconcentration,extractiontemperatureandextractiontimewiththeapplicationofultrasound,formaximumextractionofphenoliccom-poundsfromwheatbran,wasobtained,throughresponsesurfacemethodology(RSM).Theoptimumextractionconditionswereasfol-lows:ethanolconcentration,64%;extractiontemperature,60°C;andextractiontime,25min;andtheextractiontimewasthemostsigni cantparameterfortheprocess.Undertheabove-mentionedconditions,theexperimentaltotalphenoliccontentwas3.12mggallicacidequivalents/gofwheatbrantested,whichiswellmatchedwiththepredictedcontent.Ó2007ElsevierLtd.Allrightsreserved.

Keywords:Centralcompositerotatabledesign;Phenoliccompounds;Ultrasoundextraction;Wheatbran

1.Introduction

Grainscontainuniquephytochemicals.Epidemiologicalstudieshavestronglysuggestedthatdietsrichincerealsplayacrucialroleinthepreventionofchronicdiseases,suchascardiovasculardiseaseandcertaintypesofcancers(Aruoma,2003;Slavin,2000).Thebene cialhealthe ectsderivedfromtheintakeofdietsrichincerealshavemainlybeenascribedtodietary bre,ortosomeofthecompo-nentsassociatedwiththe bre,includingphenolicacids(Andreasen,Landbo,Christensen,Hansen,&Meyer,2001;Zhao,Egashira,&Sanada,2003).Itiswidelyacceptedthatphenoliccompounds,includingferulic,vanil-lic,p-coumaric,ca eic,andchlorogenicacids,arerichinthebranportionofcerealkernelsandmaycontributetothetotalantioxidantactivitiesofgrain(Baublis,Clydes-*

Correspondingauthor.Tel.:+861068985378;fax:+861068985456.E-mailaddress:jingw810@(J.Wang).

´nez-Tome´etal.,2004;Yudale,&Decker,2000;Mart

etal.,2002).Thesephenoliccompoundsexhibitinvitrochemoprotectiveandantioxidantproperties,andaresug-gestedtobemainlyresponsibleforthebene ciale ectsofadietrichincerealbran(Andreasen,Kroon,William-son,&Garcia-Conesa,2001).

Wheatbranisproducedworldwideinenormousquanti-ties,asanimportantby-productofthecerealindustry.Sev-eralinvestigationshavebeenconductedtoevaluatetheantioxidantpropertiesofwheatandwheat-basedcerealextracts(Yuetal.,2002).However,tothebestofourknowledge,thereislimitedliteratureone cientextractionofphenoliccompoundsfromwheatbran.Inordertoseekmoreenvironmentallyfriendlymethods,decreasethesol-ventconsumption,shortentheextractiontime,increasetheextractionyield,andenhancethequalityofextracts,variousnovelextractiontechniqueshavebeendevelopedfortheextractionofnutraceuticalsfromplants,includingultrasound-assistedextraction,supercritical uid

0308-8146/$-seefrontmatterÓ2007ElsevierLtd.Allrightsreserved.doi:10.1016/j.foodchem.2007.06.062