Industrial Crops and Products 62 (2014) 499506

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Industrial Crops and Products

jo ur nal home p age: www.elsev ier .com/ locate / indcrop

Phenol racowers

Eriel Forv a N.Maria LuDepartment of R, Bra

a r t i c l

Article history:Received 13 MReceived in re11 September 2014Accepted 14 September 2014

Keywords:InfusionDecoctionSolvent extracHPLCDADDPPHABTS

t thae pote dry

used to prepare the extracts: infusion, decoction, and solvent extraction (methanol). Total phenoliccompounds (using the FolinCiocalteu method), total avonoid compounds (using the UVvis colori-metric method), and antioxidant activity (by DPPH and ABTS assays) were used to evaluate theseextracts. The individual phenolic compounds found in the extracts were characterized and quantiedby HPLCDAD. Decoction extraction of the leaves showed the highest total phenolic and avonoid val-

1. Introdu

The oxidone of the diseases, imet al., 2010;

When thproduction lipids, and pFor this reabecome necradicals andet al., 2011)maintaining

CorresponE-mail add

http://dx.doi.o0926-6690/ tion ues, at 42.20 mg GAE/g dw and 39.71 mg RE/g dw, respectively. Gallic acid (3,4,5-trihydroxybenzoic acid)and rutin (quercetin-3-rutinoside trihydroxydrate) were the most abundant phenolic compounds in theleaf extracts (1.97 and 2.81 mg/g dw, respectively). Myricetin (3,3,4,5,7-hexahydroxyavone) and gal-lic acid (3,4,5-trihydroxybenzoic acid) were the phenolic compounds found in the highest amounts inthe ower extracts (16.09 and 1.36 mg/g dw, respectively) and these compounds were identied andquantied in this study for the rst time. Decoction of the yacon leaves exhibited the highest antiox-idant activity in the DPPH assay at EC50 = 220.50 g dw. Infusion of extract of the leaves exhibited moreantiradical activity in the ABTS assays than the other studied extracts (422.13 M equiv. Trolox/g dw). Inconclusion, these results indicate that the infusion and decoction of yacon leaves and owers can be con-sidered as a promising source of phenolic acids and avonoid compounds, with appreciable antioxidantproperties.

2014 Published by Elsevier B.V.

ction

ative processes that occur in human metabolism aremost important factors in the onset of cardiovascularmune system diseases, brain disorders, and cancer (Ho

Halliwell, 1997).e human immune system is suppressed by an over-of oxidizing agents the result is that nucleic acids,roteins may be damaged, which results in tissue injury.son, the search for natural non-toxic antioxidants hasessary in order to protect the human body from free

to retard the development of chronic diseases (Sun. The increased intake of natural antioxidants assists in

the balance between antioxidant and oxidizing agents

ding author. Tel.: +55 41 3361 3274.ress: erielfa@ufpr.br (E.F. de Andrade).

in the organism, reducing or preventing oxidative processes fromoccurring (Tai et al., 2011).

Studies suggest that fruits and vegetables are protective againstoxidative diseases due to the anti-oxidative character of their vita-mins and minerals, as well as the presence of avonoids andphenolic compounds (Pietta and Simonetti, 1999). Thus, consider-able attention has been directed toward the identication of naturalantioxidants that may be used for human consumption (Zhanget al., 2011).

Yacon (Smallanthus sonchifolius) (Poepp. And Endl.) H. Robin-son is a perennial herb from the Asteraceae family that is originallyfrom the Andes and which grows in several regions of world (Grauand Rea, 1997). Yacon tuber roots are consumed mainly as fruit,in contrast with most edible roots. Yacon stores carbohydratesin the form of (21) fructooligosaccharides that exert healthbenets during digestion and which can help to control constipa-tion, as well as reduce blood lipid and glucose levels (Ojansivuaet al., 2011; Valentov and Ulrichov, 2003). Natural phenolics are

rg/10.1016/j.indcrop.2014.09.0252014 Published by Elsevier B.V.ic prole and antioxidant activity of ext of yacon (Smallanthus sonchifolius)

ille de Andrade , Roberta de Souza Leone, Luciancia MassonChemical Engineering, Federal University of Paran, Postal Code 81531-990, Curitiba, P

e i n f o

ay 2014vised form

a b s t r a c t

Yacon is an Andean perennial planpresent study aimed to evaluate thof antioxidant compounds. After thts of leaves and

Ellendersen,

zil

t is cultivated in several countries around the world. Theential of extracts of yacon owers and leaves as a sourceing and powdering of the samples, three processes were

500 E.F. de Andrade et al. / Industrial Crops and Products 62 (2014) 499506

present in yacon tubers, such as chlorogenic (3-caffeoylaltraric),3,5-dicaffeoylquinic, and caffeic acids (Tekenaka et al., 2003). Theavonoid quercetin was identied after hydrolysis of yacon tuber(Valentov and Ulrichov, 2003). A recent study conrmed the ben-ets of yacoinfertility alate-onset h

Some bewhen they have shownof phytoch2003), antiactivities (Vies have shis safe in tglycemic efTopical antfrom yaconanti-inamsesquiterpe

Other stfungal and 1995). Thessesquiterpepolimatin BSchorr et al

There haerties of yato the Asterglycosides, chemical cofamily. Studowers perof avonoidglucoside, cquercetin, l

Parejo eextracts of 5effect of thetical, cosme

The aimabout the cers of S. sonantioxidant

2. Materia

2.1. Plant m

The leavduring AprParan stataltitude of herbarium

The colloven at 40

2.1.1. Prepasonchifolius

The extrSimonovskaand owerscedure was

(a) Infusion (INF): 50 ml of boiling distilled water was poured ontothe material and allowed to extract for 20 min while cooling. Thesample was collected to a 100 ml volumetric ask and analyzedimmediately.

coctied wperak anvent0 ml

wasedi

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withn tuber extract as a herbal supplement in treating malend alleviating chronic low testosterone levels, such asypogonadism (LOH) syndrome (Park and Han, 2013).necial properties have been attributed to yacon leavesare used as a traditional tea (Aybar et al., 2001). Studies

that the extract of dried yacon leaves has a varietyemicals activities, including antimicrobial (Lin et al.,-inammatory (Oliveira et al., 2013), and antioxidantalentov and Ulrichov, 2003). In recent years, stud-own that the use of aqueous extracts of yacon leaveshe treatment of diabetes in rats, proving the hypo-fect (Barcellona et al., 2012; Simonovska et al., 2003).i-dematous in vivo activity was observed in extracts

leaves and this activity may be a consequence of anmatory propriety of the extract due to the presence ofne lactones (Lin et al., 2003; Oliveira et al., 2013).udies have demonstrated that yacon displays anti-anti-bacterial actions (Joung et al., 2010; Inoue et al.,e activities have been attributed to the presence ofne lactones, such as enhydrin, uvedalin, sonchifolin, and, which are present in the leaves (Inoue et al., 1995;., 2007).ve been few studies regarding the phytochemical prop-con owers; however, some features that are commonaceae family may also be assigned to yacon. Flavonoidavonoids, and phenolic compounds are importantnstituents of the owers of the same species of yaconies of chamomile (Matricaria recutita L. Asteraceae)formed by Novkov et al. (2010) showed the presences, phenolic acids, and coumarins, including apigenin-7-hlorogenic acid, cinnamic acid, ferulic acid, caffeic acid,uteolin, apigenin, kaempherol, and rutin.t al. (2003) evaluated the antioxidant potential of4 plant species of Asteraceae, revealing the antioxidantse extracts and their potential use by the pharmaceu-tic, and food industries.s of the present study were to contribute to knowledgehemical composition of extracts of the leaves and ow-chifolius, with especially emphasis on compounds with

activity.

ls and methods

aterial preparation

es and owers of S. sonchifolius (yacon) were harvestedil, 2011, in So Jos dos Pinhais, a city near Curitiba,e, Brazil (coordinates: 253714 latitude, 490740W,906 m). A voucher specimen was deposited in the

of the Federal University of Paran.ected leaves were carefully dried under air ow in anC for 24 h. The owers were dried at 50 C for 72 h.

ration of the aqueous and methanolic extract of S.

action methodology used in this study was based on et al. (2003) with some modications. Dry yacon leaves

(1.0 g) were extracted as follows; the extraction pro- repeated three times for each sample.

(b) Detilltemas

(c) Sol(15pleimm

2.2. St

Thelytical acid), zoic aacid), hexahy(querc(rutin 2,2-Az()-6-(Troloxused i(Germ(Italy).

2.3. H

HPLseries 1with athermoEclipseferent v/v) antion ofgradieand 75follow65% B (rate wrecordwith incompaples, awere plipore using nologicompoibratiocaffeicand kadata pmean

2.4. To

Themine tsonchifmixedon (DEC): the material was kept in 50 ml of boiling dis-ater under reux for 20 min and left to cool at roomture. The sample was collected to a 100 ml volumetricd analyzed immediately.

extraction (MTN): a Soxhlet extractor with methanol/72 h) was used. After the extraction period the sam-

collected to a 200 ml volumetric ask and analyzedately.

rds and solvents

owing reagents and HPLC solvents were all of ana-e: trans-4-hydroxy-3-methoxy cinnamic acid (ferulicihydroxycinnamic acid (caffeic acid), hydroxyben-

(salicylic acid), 3,4,5-trihydroxybenzoic acid (gallic-4-hidroxycinamic acid (p-coumaric acid), 3,3,4,5,5,7-yavone (myricetin), 3,3,4,5,7-pentahydroxyavonedehydrate), queretin-3-rutinoside trihydroxydrateydrate), 3,4,5,7-tetrahydroxyavone (kaempherol),is(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS),oxy-2,5,7,8-tetramethylchromane-2-carboxylic acidd 2,2-diphenyl-1-picrylhydrazyl (DPPH). The solventse HPLC tests were purchased from SigmaAldrichand the other reagents were purchased from Carlo Erba

DAD analyses

AD analyses were performed using an Agilent HPLC HPLC instrument (Agilent Technologies, USA) equippedernary pump, a diode array detector (DAD), a column, and an autosampler. The column used was a Zorbax

(5 m; 4.6 mm 250 mm) (Agilent, USA) using two dif-nt programs: a mobile phase: solvent A: formic acid (1%,vent B: methanol. For the identication and quantica-olic acids, the elution was achieved with the followingtion: 25% B to 40% B (40 min), 40% B to 75% B (15 min),

25% B (10 min). For the measurement of avonoids, theradient elution was used: 55% B to 45% B (20 min), 45% toin), and 65% B to 55% B (10 min). The mobile phase owml min1 in both schedules. The chromatograms were

both 278 nm (phenolic acids) and 325 nm (avonoids)ion volume of 10 l. Identication was performed by

of retention times, co-injection with authentic sam-V spectra. The standards and mobile phase solutionsltered through 0.45 mm in pore size membrane (Mil-Bedford, MA). The data were integrated and analyzedistation for LC Rev. B.02.01-SR1 [260] (Agilent Tech-

SA) software. The concentration of individual phenolic was calculated as mg/g dry weight using external cal-ves obtained for each phenolic standard. Ferrulic acid,, salicylic acid, gallic acid, myricetin, quercetin, rutin,herol were studied and determined in the samples. Theted are the average of three measurements given asdard deviation.

henolic compounds

Ciocalteu method (Lim et al., 2011) was used to deter-henolic compounds in the aqueous and methanolic S.

extract samples. A 1 ml portion of the sample was 1 ml of FolinCiocalteus reagent. After 3 min, 1 ml of

E.F. de Andrade et al. / Industrial Crops and Products 62 (2014) 499506 501

saturated Na2CO3 (35%) was added to the mixture. The reaction wasmaintained in the dark for 90 min and its absorbance was measuredat 725 nm relative to a blank. The calibration curve was carried outwith gallic acid solution as a reference standard and total phenoliccontent waof gallic acid(GAE mg/g d

2.5. Total

The totaaccording tmixed withAlCl3 and 1mixture wastand for 170% ethanoand total aation of trileaves or o

2.6. DPPH r

The DPPand owerWilliams etadded to 3.decrease intion. The exmedium wa30 M, 40 determinedthe amountconcentratiwas exprescient concen(EC50= g dw

2.7. ABTS ra

The ABTactivity of taccording toconcentratireacting ABand allowinture for 12ethanol to adiluted ABTpound or TrThe absorbawas used ations were absorbanceconcentratidata. The ination of trip(M ET/g dw

2.8. Extract

The deteon the 920.1extracts preand evaporin an oven a

as mean standard deviation of triplicate as percentage (%) of totalsolids from extracts of leaves or owers of S. sonchifolius.

2.9. Statistical analysis of data

stat varilue FLR-INphenolic cofrom the yastrong corr(r2 = 0.937),tionship waDPPH antiohighest corcorrelation DPPH antio

The posiity and totaincrease in the extractscompoundsin extract oregion (Bay

3.5. ABTS ra

The sulfocicacidtotal antioxfrom S. soncon the dirthrough theantioxidantcompoundsthe inhibitireference (Raqueous exof the ABTin Table 4.between 65the ower extracts prthe FLR-INFfrom leaveABTS scaveof total phactivity of lfollows: ELwere rankeFLR-DEC > F

d cos andand vel oids ar bo986 a

favoomp

obseresulomphas bKim

clus

his sidantineds wehe mtin ahestibiteighens hahenoancecids aties, uses

wled

na-Brazledg

nces

.J., Riact of opharFLR DEC 282.09 FLR MTN 1014.29 EL NF 495.26 EL DEC 220.50 EL MTN 3571.85

a column followed by different letters are signicantly different by Tukeys test (P EL-INF > EL-xtracts of yacon owers showed similar results to those

the leaves and they were ranked as follows: FLR-F > FLR-MTN. Good correlation was observed between

mpounds and DPPH antioxidant activity in the extractscon leaves (r2 = 0.998). The ower extracts also showedelation between DPPH and total phenolic compounds

with a high signicance level (P < 0.05). A similar rela-s also obtained between total avonoid content and

xidant (EC50) activity; the ower extracts presented therelation (r2 = 0.998). The leaf extracts showed a weak(r2 = 0.259) between total avonoid compounds andxidant activity.tive relationship between the DPPH antioxidant activ-l phenolic and avonoid compounds indicated that thephenolic compounds favored the antioxidant activity of. This relationship between total phenolic and avonoid

and antioxidant activity was also previously reportedf Rosa damascene Mill. and also plants from the Andeandar and Baydar, 2013; Chirinos et al., 2013).

dical scavenging activity

ABTS [2,2-azinobis-(3-ethylbenzothiazoline-6-)] scavenging method was used to measure theidant activity of the aqueous and methanolic extractshifolius leaves and owers. The ABTS method is basedect production of blue/green ABTS+ chromophore

reaction between ABTS and potassium persulfate. The activity is evaluated by the capacity of the antioxidant

to reduce the radical cation ABTS+ to ABTS, promotingon of absorbance at 734 nm, using Trolox as standarde et al., 1999). As in the DPPH scavenging method, the

tracts showed the highest antioxidant activity in termsS scavenging method and the results are presented

The ABTS antioxidant activity varied considerably;.40 and 209.37 and 44.59422.13 M Trolox/g dw in

Goopoundleaves high leavonoship fo(r2 = 0.

Thenolic cresultsThese nolic cwhich 1999;

4. Con

In tantioxdetermpoundwere tMyricethe higity exhwere hrelatiototal pimportnolic apropertional

Ackno

TheCAPESacknow

Refere

Aybar, MextrEthnand leaf extracts, respectively. The LE-INF and LE-DEC

esented more signicant antioxidant activity than and FLR-DEC extracts. Both the methanolic extractss and owers showed the worst results in terms ofnging, which can be explained by the lower amountenolic and avonoid compounds. The antioxidant

eaf extracts, in terms of the M Trolox/g dw, ranked as-DEC > EL-INF > EL-MTN. Likewise, the ower extractsd in terms of the M equiv. Trolox/g dw as follows:LR-INF > FLR-MTN.

Barcellona, C.S2012. Safeand its ma

Brand-Williamevaluate a

Baydar, N.G., Bdant capac41, 3753

Chirinos, R., Pcompoundmedicinal145152.213.18 21.73a 65.40 0.65b

422.13 12.59a391.55 22.32b

44.59 2.26c.

rrelation was observed between total phenolic com- ABTS antioxidant activity for the extracts from theowers (r2 = 0.999 and r2 = 0.992 respectively), with af signicance (P < 0.05). The relationship between totalnd ABTS radical scavenging showed a strong relation-th extracts from owers and leaves of S. sonchifoliusnd r2 = 0.933, respectively).rable and signicant relationship between total phe-ounds and ABTS antioxidant activity strengthens therved in the DPPH scavenging method used in this study.ts support the hypothesis that an increase in total phe-ounds will increase the antioxidant activity of extracts,een previously reported (Chirinos et al., 2013; Kalt et al.,et al., 2003).

ion

tudy, total phenolic compounds, total avonoids, and activity of extracts of yacon owers and leaves were. The highest levels of total phenolic and avonoid com-re found in decoction leaf extracts. Gallic acid and rutinost abundant phenolic compounds in the leaf extracts.nd gallic acid were the phenolic compounds found in

amounts in the ower extracts. The antioxidant activ-d by the infusion and decoction of leaves and owersr than that of methanol extract. Signicant positive cor-ve been found between antioxidant activity and bothlic and avonoid compounds. The results highlight the

of these matrixes as a promising source of natural phe-nd avonoid compounds, with appreciable antioxidantso this study can be formed the science base of tradi-of this plant.

gement

ncial resources for this research were provided byil (PNPD 02729/09-1), whom the authors gratefullye.

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Phenolic profile and antioxidant activity of extracts of leaves and flowers of yacon (Smallanthus sonchifolius)1 Introduction2 Materials and methods2.1 Plant material preparation2.1.1 Preparation of the aqueous and methanolic extract of S. sonchifolius

2.2 Standards and solvents2.3 HPLCDAD analyses2.4 Total phenolic compounds2.5 Total flavonoid compounds2.6 DPPH radical scavenging assay2.7 ABTS radical scavenging assay2.8 Extraction yield2.9 Statistical analysis of data

3 Results and discussion3.1 Total phenolic compounds3.2 Total flavonoid compounds3.3 Individual phenolic acids and flavonoid compounds3.4 DPPH radical scavenging activity3.5 ABTS radical scavenging activity

4 ConclusionAcknowledgementReferences