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Industrial Crops and Products 62 (2014) 499506
Contents lists available at ScienceDirect
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: [email protected] (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
anda
follgrad3,4-dcid transdroxetin trih
ino-bhydr), ann thany)
PLC
CD200
quatstat
C18solved sol
phennt elu% B toing g10 mas 1 ed atjectrisonnd Ure-Co., Chemes,
Uundsn cur
acidempresen
stan
tal p
Folinhe polius
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