This article was downloaded by: [Queensland University of Technology]On: 21 November 2014, At: 12:54Publisher: Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registeredoffice: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK

International Journal of Fruit SciencePublication details, including instructions for authors andsubscription information:http://www.tandfonline.com/loi/wsfr20

High Levels of Resveratrol in GrapesCultivated at High Altitude Valleys inBoliviaMarco Taquichiria, Ruth Ayardea, Pastor Gutierreza, Atma-SolBustosbc, Carolina Paredesbc, Juan Carlos Callisayabc, Juan CarlosSurcob, Eduardo R. Palenqued, Flavio Ghezzid, Juan AntonioAlvaradob & J. Mauricio Peñarrietabc

a Departamento de Física, Facultad de Ciencia y Tecnología,Universidad Autónoma Juan Misael Saracho, Tarija, Boliviab Centro de Estudios e Investigaciones en Química de Alimentos,Universidad Mayor de San Andrés, La Paz, Boliviac Instituto de Investigaciones en Productos Naturales, UniversidadMayor de San Andrés, La Paz, Boliviad Instituto de Investigaciones Físicas, Universidad Mayor de SanAndrés, La Paz, BoliviaPublished online: 28 Apr 2014.

To cite this article: Marco Taquichiri, Ruth Ayarde, Pastor Gutierrez, Atma-Sol Bustos, CarolinaParedes, Juan Carlos Callisaya, Juan Carlos Surco, Eduardo R. Palenque, Flavio Ghezzi, JuanAntonio Alvarado & J. Mauricio Peñarrieta (2014) High Levels of Resveratrol in Grapes Cultivatedat High Altitude Valleys in Bolivia, International Journal of Fruit Science, 14:3, 311-326, DOI:10.1080/15538362.2013.819748

To link to this article: http://dx.doi.org/10.1080/15538362.2013.819748

PLEASE SCROLL DOWN FOR ARTICLE

Taylor & Francis makes every effort to ensure the accuracy of all the information (the“Content”) contained in the publications on our platform. However, Taylor & Francis,our agents, and our licensors make no representations or warranties whatsoever as tothe accuracy, completeness, or suitability for any purpose of the Content. Any opinionsand views expressed in this publication are the opinions and views of the authors,and are not the views of or endorsed by Taylor & Francis. The accuracy of the Contentshould not be relied upon and should be independently verified with primary sourcesof information. Taylor and Francis shall not be liable for any losses, actions, claims,proceedings, demands, costs, expenses, damages, and other liabilities whatsoever orhowsoever caused arising directly or indirectly in connection with, in relation to or arisingout of the use of the Content.

This article may be used for research, teaching, and private study purposes. Anysubstantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &Conditions of access and use can be found at http://www.tandfonline.com/page/terms-and-conditions

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

International Journal of Fruit Science, 14:311–326, 2014Copyright © Taylor & Francis Group, LLCISSN: 1553-8362 print/1553-8621 onlineDOI: 10.1080/15538362.2013.819748

High Levels of Resveratrol in Grapes Cultivatedat High Altitude Valleys in Bolivia

MARCO TAQUICHIRI1, RUTH AYARDE1, PASTOR GUTIERREZ1,ATMA-SOL BUSTOS2,3, CAROLINA PAREDES2,3,

JUAN CARLOS CALLISAYA2,3, JUAN CARLOS SURCO2,EDUARDO R. PALENQUE4, FLAVIO GHEZZI4,

JUAN ANTONIO ALVARADO2, and J. MAURICIO PEÑARRIETA2,3

1Departamento de Física, Facultad de Ciencia y Tecnología,Universidad Autónoma Juan Misael Saracho, Tarija, Bolivia

2Centro de Estudios e Investigaciones en Química de Alimentos,Universidad Mayor de San Andrés, La Paz, Bolivia

3Instituto de Investigaciones en Productos Naturales, Universidad Mayorde San Andrés, La Paz, Bolivia

4Instituto de Investigaciones Físicas, Universidad Mayor de San Andrés,La Paz, Bolivia

Trans-resveratrol, total antioxidant capacity (TAC), and totalphenolic compounds were assessed in Bolivian grape cultivars col-lected at high altitude valleys. The TAC of the grapes ranged from0.8 to 22 µmol Trolox equivalents/g dry matter determined by2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), and from0.6 to 10 determined by the ferric reduction antioxidant power.In the present study, we observed that under certain conditionstrans-resveratrol levels in Bolivian grapes are 10-fold higher thanthe reported data from the literature. Additionally, the temporalevolution in three different solar ultraviolet-B radiation levels wascarried out to understand their effect on the oxidative processes.

KEYWORDS trans-resveratrol, antioxidant capacity, grapes, solarultraviolet–radiation, Bolivia

Address correspondence to J. Mauricio Peñarrieta, Centro de Estudios e Investigacionesen Química de Alimentos, Universidad Mayor de San Andrés, P.O. Box 303, La Paz, Bolivia.E-mail: jmpenarrieta1@umsa.bo

311

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

312 M. Taquichiri et al.

INTRODUCTION

Resveratrol (3,5,4′-trihydroxystilbene: C14H12O3) is a stilbene phytoalexinand is considered a very important antioxidant compound found in certainfoods and plants. Its antioxidant properties are associated with health benefitclaims, including cardioprotective effects, e.g., inhibition of LDL oxidationand inhibition of platelet aggregation in the blood; and neuroprotectiveeffects, in its therapeutic potential against Alzheimer’s disease, among othereffects and applications (Potrebko and Resurrection, 2009; Li et al., 2006;Yang et al., 2000).

Resveratrol, a phytoalexin, is insoluble in water but is soluble in organicsolvents, such as ethanol. It is produced in some plants as a defense responseto external stress, such as fungal infection and UV solar radiation (Stervboet al., 2007; Cantos and Barberan, 2001). Furthermore, in some studiesresveratrol in nuts and grapes was found to increase when exposed to artifi-cial UV radiation (Cantos and Barberan, 2001; Madronich et al., 1988). Boliviais a suitable country to carry out research relating to high solar UV radiationlevels due to its high altitude and low latitude as will be described below.

The sun emits radiation on a broad range of the electromagnetic spec-trum, but ultraviolet radiation represents only a small part of the total sunlightintensity. This small portion, around 5% of the total solar radiation, is poten-tially harmful for living organisms since high fluencies of UVB photons cancause direct cellular damage (Parrish et al., 1992; Brosché and Strid, 2003).Nevertheless, moderate levels of UVB radiation can stimulate protectivemechanisms as responses to this level of aggression (Tevini and Teramura,1989).

There are many studies demonstrating that ultraviolet radiation reachingthe earth’s surface increases with altitude and varies with latitude (Krscin,2000; Zaratti et al., 2003; Pfeifer et al., 2006). Bolivia’s sub-equatorial andinter Andean valleys located mainly at the end of the Andean mountain rangehave elevations of between 2000–4000 m.a.s.l. and latitudes in the rangeof 10◦–20◦ South. Grape plantations are found in many of these valleys.Representative grape cultivars include: Muscat of Alexandria, Red Globe,Cardinal, Italia, Syrah, Cabernet Sauvignon, Malbec, and Merlot. Due to theiraltitude and latitude, the valleys of the Cercado Province of Tarija and theLoayza Province of La Paz have many days when the solar UV radiation ismore intense than other places in Bolivia with similar grape cultivars.

The economic importance of these cultivars is very high since 70% of thecountry’s grape plantations are located in Tarija (Lobato and Prudencio, 2012;Taquichiri and Paco, 2008). The amounts of trans-resveratrol in the grapesfrom Loayza province in La Paz and those from Tarija valleys compared withother studies carried out in other locations (Pascual-Martí et al., 2011; Li et al.,2006; Cantos et al. 2000; Moreno et al., 2008) and even where grapes wereirradiated with UV (Moreno et al., 2008; Cantos et al., 2006).

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

Resveratrol in Bolivian High Valley Grapes 313

The present work reports the measurement of the total antioxidantcapacity (TAC), phenolic, and resveratrol content in grapes collected in thementioned valley regions of Bolivia. Thus, it could be assumed that Boliviangrapes growing at high altitudes have developed a good natural protectionagainst oxidation. Our results lead us to conclude that grapes from this part ofthe world are a potential rich source of polyphenolic and other antioxidants.

MATERIALS AND METHODS

Chemicals

Folin-Ciocalteu reagent, gallic acid, sodium carbonate, and acetone (p.a.)were purchased from Merck (Darmstadt, Germany). ABTS [2,2′-azino-bis(3-ethylbenzotiazoline-6-sulphonic acid)], potassium persulphate, Trolox(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid, 97%), TPTZ (2,4,6-tripyridyl-s-triazine), DPPH (2,2-diphenyl-1-picrylhydrazyl), Polydatin, andmethanol (HPLC grade) were obtained from Sigma-Aldrich (St. Louis, MO,USA). Ferric chloride was purchased from ICN Biomedicals Inc. (Costa Mesa,CA, USA), acetic acid (glacial p.a.) and sodium acetate from BDH ChemicalsLtd. (Poole, UK). Resveratrol was purchased from ChromaDex (Irvine, CA,USA).

Plant Material

Nineteen grape samples were collected in the valley region of theLoayza province in Bolivia’s La Paz Department, at altitudes from 1800 to3000 m.a.s.l. during Mar. 2011. The description of the samples is givenin Table 1. In addition, to evaluate the effects of solar UV levels on thesynthesis of resveratrol, four vineyards were selected in the valley regionof Bolivia’s Tarija Department. Fifteen grape sample points were identifiedand the grapes were collected on four different occasions following theexperiment outlined below.

UV Determinations

The valley region of the Loayza province is located in the West of Boliviaand lies between 1800–3000 m a.s.l. UVA and UVB levels were measuredin situ at each sample collection point using an Optometer X1-1 purchasedfrom Gigahertz-Optik GmbH (Tuerkenfeld, Germany) (Table 1).

Tarija is located in the southernmost part of Bolivia, bordering Argentinaand Paraguay, (21◦ S, 64◦ W) at 1900 m.a.s.l. Due to its altitude and latitude,the valley region of Tarija has many days with solar UV radiation, which

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

TAB

LE1

Des

crip

tion

ofth

eG

rape

Sam

ple

sColle

cted

inth

eLo

ayza

Pro

vince

and

UVA

-UV

BM

easu

rem

ents

Coord

inat

esU

V(W

/m

2)

Dat

eH

our

Alti

tude,

m.a

.s.l.

Gra

pe

sam

ple

szCulti

var

South

Wes

tU

VAU

VB

26M

ar.20

1114

:24

2853

MB1

Bla

ckO

live

17◦

7′ 31.

5′′67

◦35

′ 56.

5′′61

.01.

6515

:00

2935

MB2

Bla

ckO

live

17◦

8′ 35.

8′′67

◦33

′ 19.

3′′61

.01.

6515

:00

2935

MB3

Bla

ckO

live

17◦

8′ 35.

8′′67

◦33

′ 19.

3′′61

.01.

6515

:41

2976

MB

4B

lack

Bord

eaux

17◦

9′ 37′′

67◦

33′ 2

3.7′′

61.0

1.65

15:5

529

87M

B5

Bla

ckCre

ole

17◦

9′ 33.

3′′67

◦33

′ 21.

5′′61

.01.

6515

:55

2987

MW

1To

ronte

l17

◦9′ 3

3.3′′

67◦

33′ 2

1.5′′

61.0

1.65

15:5

930

88M

B6

Bla

ckCre

ole

17◦

10′ 1

3.3′′

67◦

32′ 2

5.7′′

61.0

1.65

27M

ar.20

1111

:02

2550

MB

7B

lack

Cre

ole

17◦

0′ 35.

9′′67

◦37

′ 0.0

′′61

.01.

6511

:02

2550

MB

8Cab

ernet

Sauvi

gnon

17◦

0′ 35.

9′′67

◦37

′ 0.0

′′61

.01.

6511

:50

2825

MB

9B

lack

Cre

ole

17◦

1′ 47.

2′′67

◦33

′ 41.

5′′45

.01.

3011

:50

2825

MB

10B

lack

Bord

eaux

17◦

1′ 47.

2′′67

◦33

′ 41.

5′′45

.01.

3011

:50

2825

MB

11Cab

ernet

Sauvi

gnon

17◦

1′ 47.

2′′67

◦33

′ 41.

5′′45

.01.

3011

:50

2825

MW

2To

ronte

l17

◦1′ 4

7.2′′

67◦

33′ 4

1.5′′

45.0

1.30

11:5

028

25M

W3

Musc

at17

◦1′ 4

7.2′′

67◦

33′ 4

1.5′′

45.0

1.30

11:5

028

25M

B12

Bla

ckO

live

17◦

1′ 47.

2′′67

◦33

′ 41.

5′′45

.01.

3013

:15

2825

MB

13B

lack

Musc

at17

◦1′ 4

7.2′′

67◦

33′ 4

1.5′′

31.2

1.00

28M

ar.20

119:

3822

74M

B14

Bla

ckB

ord

eaux

17◦

57′ 1

4′′67

◦4′ 1

8′′48

.80.

809:

3822

74M

B15

Bla

ckCre

ole

17◦

57′ 1

4′′67

◦4′ 1

8′′48

.80.

809:

3822

74M

B16

Bla

ckO

live

17◦

57′ 1

4′′67

◦4′ 1

8′′48

.80.

80

z B:B

lack

grap

esa

mple

;W

:W

hite

grap

esa

mple

.

314

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

Resveratrol in Bolivian High Valley Grapes 315

FIGURE 1 Time dependence of solar UV-B irradiance (I) for two typical clear sky days: onein winter and one in summer (15 July 1998 and 15 January 1998, local time). The data wasmeasured using a YES UV-B1 pyranometer.

are more intense than other places with similar grape cultivars (Fig. 1) andcompare with equivalent data obtained in La Paz.

The study in Tarija’s valley was conducted during the 2010–2011 sea-son in four vineyards: National Centre for Wine (CENAVIT), (21◦ 41′ 14′′ S,64◦ 39′ 25′′ W, 1738 m), providing cv. Carignan and Muscat of Alexandria,Campos de Solana vineyard (21◦ 32′ 28′′ S, 64◦ 36′ 17 W, 1870 m) providingcv. Cabernet Sauvignon, Kohlberg Vineyards (21◦ 35′ 29′′ S, 64◦ 36′ 42′′ W,1861 m), providing cv. Syrah and La Concepción Vineyards (21◦ 41′ 54′′ S,64◦ 40′ 18′′ W, 1733 m), providing cv. Cabernet Sauvignon. To simulate dif-ferent levels of attenuation of solar UV-B radiation, 10 plants were selected ineach vineyard and three contrasting situations were prepared: natural levelsof UV (no attenuation A0); 20% UVB attenuation using a black anti hail net(A1), and 60% UVB attenuation using a yellow 250-nm polyester filter (A2).

The attenuation factors were estimated using a Li-Cor light meter(Lincoln Instruments Inc., Lincoln, NE, USA). The experiment was installed2 weeks after veraison date (15 Dec. 2010) and left in situ until the harvestdate (1 Mar. 2011).

Sample Preparation

Each sample collection was composed of 40 to 50 randomly selected berries.Free polyphenolic antioxidants were extracted with methanol:water (9:1,by volume) in a liquid:sample proportion of 10:1 by vortexing and thensonicating the sample in an ice-water bath (0◦C, 15 min). The mixture was

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

316 M. Taquichiri et al.

centrifuged at 12000× g for 30 min at 4◦C, and the aspirated supernatant wasstored at −80◦C (Halvorsen et al., 2002). The extraction was performed induplicates over a period of 3 days.

Measurement of Total Antioxidant Capacity and Total PhenolicCompounds

The total antioxidant capacity (TAC) was measured using the ABTS and FRAPmethods as described by Peñarrieta et al. (2008). The results are expressedas µmol TroloxTM equivalents per gram of dry matter (µmol TE/g (dm)). Thetotal amount of phenolic compounds (TPH) was determined as previouslydescribed (Peñarrieta et al., 2009) and the results expressed as µmol gallicacid equivalents per gram of dry matter (µmol GAE/g (dm)).

High-Performance Liquid Chromatography

The resveratrol was separated using an Agilent liquid chromatographic sys-tem (series 1000, Palo Alto, CA, USA), equipped with a quaternary pump withdegasser (G1354A), an auto-injector, a column oven, and a diode-array detec-tor (DAD). The column was a 3.5 × 150 mm Kromasil C18 reversed-phasetype and was protected by a 10-mm pre-column (Eka Chemicals, SeparationProducts, Bohus, Sweden). The flow rate was 0.8 ml/min and the injectionvolume was 20 µl. The mobile phase was a binary solvent system consistingof (A) 1% acetic acid/water and (B) methanol and the gradient used was 40%B at 0 min 65% B after, 5 min, 90% B after 10 min, and 40% B after 15 minuntil 17 min. The UV absorbance of the eluate was recorded using a multiplediode array detector (190–550 nm). Retention times and absorbance spectrumprofiles were compared with standards. Pure standard resveratrol was alsoadded to the samples as a control and peak splitting was used as an indica-tion of a potential misinterpretation (Peñarrieta et al., 2009, 2011) (Fig. 2).

Dry Matter Content

The dry matter content was determined in triplicate after drying approxi-mately 2 g of the sample at 100◦C to obtain a constant weight.

RESULTS

UV Measurements

Figure 1 shows the high levels of UVB in La Paz for sunny days in Januaryand July; the curve for Tarija is similar but the peak is 8% less. At an altitudeof 3700 m.a.s.l. and at these latitudes the Earth’s surface receives an average

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

Resveratrol in Bolivian High Valley Grapes 317

FIGURE 2 Correlation between (A) ABTS vs. FRAP (grape skins), (B) ABTS vs. FRAP (grapepulps), and (C) ABTS vs. TPH (whole grapes).

dose per second of 50.0 W/m2 of UVA and 1.5 W/m2 of UVB at midday inOctober. This compares with 45.7 W/m2 for UVA and 0.8 W/m2 for UVB2750 m.a.s.l. on a clear sky, sunny day (29 Oct. 2009).

As explained in detail in the supporting information, wide horizons(broad locations), such as those found in plains, have much more UV than

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

318 M. Taquichiri et al.

those located at the bottom of valleys. The wide inter Andean valleys of Tarijareceive higher levels of direct UVR than narrower valleys, such as those ofLuribay. It is calculated that the eastern profiles in Tarija prevent direct UVRfor angles of less than 3◦ and in the western profiles angles of less than 2◦while the respective angles in Luribay are less than 10◦ western and less than19◦ eastern. Thus, Luribay has around 30% more diffuse UVB (Tórrez, 2004)and we can conclude that direct sunlight is 72% in Tarija and 64% in Luribay.

Statistical Analysis

The data is reported as mean and standard deviation (SD) for six replicatesmeasured over 3 days for TAC, FRAP, and TPH.

Total Antioxidant Capacity (TAC) and Total Phenolic Content (TPH)

For samples collected in the Loayza province, the skins were separated fromthe grape pulp. The TAC and TPH were measured using a SpectrophotometerUV/Vis Lamda 25 (Perkin Elmer, Shelton, WA, USA) in both parts of the fruitand the values are summarized in Table 2. The TAC of the skin samplesranged from 3 to 32 µmol Trolox equivalents/g dry matter assessed by theABTS method while the range varied from 2 to 7 by the FRAP method. Thevalues obtained from pulps were far lower ranging from 0.14 to 3.0 and0.12 to 2.0 by ABTS and FRAP, respectively. However, the values obtainedin white grape pulps were higher than those from black grapes and theopposite was observed when these parameters were measured in the grapeskins.

The correlation between FRAP and ABTS in grape skins shows twoclusters (Fig. 2A) that could be attributed to the chemical composition inthe grape skins, where most of phenolics can be found that vary consider-ably while the composition in pulp is similar for all cultivars. The methodsshowed correlation according to the Pearson method (Fig. 2B), which is inaccordance with the literature in particular between FRAP and ABTS in pulpswith a correlation coefficient of 0.98 (Peñarrieta et al., 2008; Nilsson et al.,2005; Saura-Calixto and Goñi, 2006).

The correlation coefficient for the phenolic content (TPH) has the sametendency as in TAC (Fig. 2C) showing higher values in skin than grape pulp.For instance, the range in skin was from 2–32 µmol GAE/g while the pulpsranged from 1 to 3.

To see the temporal evolution of antioxidants, the samples from Tarijawere collected on four occasions in 2011: (I): 9 Feb.; (II): 22 Feb.; (III): 4 Mar.;and (IV): 22 Mar. TAC and TPH were measured using a spectrophotometerUV/VIS UNICO (United Products & Instruments Inc., Dayton, NJ, USA)(Table 3). The extracts were obtained from the whole berries (skin + pulp)for practical reasons.

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

TAB

LE2

TAC

Ass

esse

dU

sing

the

AB

TS

and

FRA

PM

ethods,

Toge

ther

with

Tota

lPhen

olic

Com

pounds

(TPH

)an

din

Gra

pe

Pulp

san

din

Gra

pe

Skin

sfr

om

Loay

zaPro

vince

.The

TAC

Dat

aar

eExp

ress

edas

µm

olTE/g

(dm

),TPH

asµ

molG

AE/g

(dm

),an

dtr

an

s-Res

vera

trolas

mg/

g(d

m)

Gra

pe

pulp

sG

rape

skin

s

AB

TS

FRA

PTPH

AB

TS

FRA

PTPH

Code

Mea

nSD

Mea

nSD

Mea

nSD

Mea

nSD

Mea

nSD

Mea

nSD

tra

ns-

Res

vera

trol

MB

20.

210.

010.

180.

041.

900.

32.

880.

103.

320.

432.

100.

10.

003

MB

32.

770.

062.

190.

211.

800.

218

.49

1.16

3.69

0.33

7.80

0.6

0.06

0M

B4

0.89

0.07

0.95

0.14

2.10

0.2

14.6

80.

672.

280.

318.

400.

80.

005

MB

50.

780.

070.

650.

081.

500.

19.

000.

762.

110.

174.

900.

50.

040

MW

10.

590.

040.

150.

013.

200.

37.

500.

366.

730.

533.

000.

30.

001

MB

70.

140.

000.

120.

031.

000.

15.

390.

125.

080.

451.

800.

20.

006

MB

80.

420.

020.

250.

051.

500.

39.

420.

661.

830.

163.

600.

50.

050

MB

91.

290.

071.

030.

121.

800.

328

.01

1.45

3.00

0.18

5.70

0.5

0.05

0M

B11

0.41

0.02

0.32

0.05

2.20

0.2

31.8

72.

944.

940.

6326

.90

1.8

0.00

4M

W2

0.39

0.03

0.28

0.05

2.20

0.3

3.13

0.11

4.02

0.46

2.30

0.2

0.06

0M

W3

2.36

0.09

1.96

0.11

2.60

0.2

30.1

62.

095.

120.

4932

.10

1.6

0.00

4M

B12

0.14

0.01

0.25

0.05

1.20

0.1

3.37

0.08

3.33

0.40

1.80

0.3

0.04

0M

B13

0.67

0.04

0.58

0.09

1.30

0.1

26.1

01.

824.

770.

3632

.10

3.8

0.00

2M

B14

0.44

0.02

0.41

0.04

1.40

0.3

7.22

0.24

7.32

0.72

4.60

0.5

0.08

0M

B15

0.40

0.02

0.43

0.04

1.20

0.1

22.4

81.

243.

460.

377.

700.

80.

004

Mea

nB

lack

Gra

pes

0.71

0.61

1.58

14.9

13.

768.

950.

030

Mea

nW

hite

Gra

pes

1.11

0.80

2.67

13.6

05.

2912

.47

0.02

0

319

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

TAB

LE3

Tem

pora

lEvo

lutio

nofTA

C(b

yth

eA

BTS

and

FRA

PM

ethods)

and

Tota

lTPH

and

inG

rapes

Colle

cted

inTar

ijaVal

leys

;the

TAC

dat

aar

eex

pre

ssed

asµ

molTE/g

(dm

),TPH

asµ

molG

AE/g

(dm

)

ABTS

FRAP

TPH

Vin

eyar

dCulti

var

CO

DE

TAC

ISD

TAC

IISD

TAC

III

SDTA

CIV

SDTA

CI

SDTA

CII

SDTA

CII

ISD

TAC

IVSD

TPH

ISD

TPH

IISD

TPH

III

SDTPH

IVSD

CEN

AVIT

Car

iñen

a

(bla

ck)

A0

4.40

0.47

8.76

1.00

6.64

0.54

18.1

11.

098.

340.

305.

860.

075.

280.

418.

260.

0711

.29

0.26

7.02

0.08

7.11

0.08

12.4

70,

12

A1

14.4

81.

3113

.85

1.43

8.80

0.62

17.3

70.

899.

580.

177.

060.

076.

300.

278.

050.

0416

.80

1.06

17.8

70.

217.

700.

1211

.01

0,24

A2

10.2

60.

908.

780.

399.

440.

7018

.34

0.86

6.51

0.23

5.61

0.04

6.27

0.12

1.08

0.01

8.47

0.25

6.49

0.08

7.40

0.08

11.3

00,

16

KO

HLB

ERG

Syra

hA0

10.9

30.

849.

910.

508.

910.

6416

.51

1.23

6.41

0.28

5.33

0.04

5.25

0.07

7.17

0.03

10.5

10.

369.

820.

068.

450.

068.

630,

15

A1

12.4

50.

4710

.40

0.22

8.53

0.57

15.5

81.

038.

410.

465.

460.

035.

410.

056.

510.

0412

.29

0.39

11.6

10.

107.

160.

0811

.36

0,15

A2

7.46

0.25

8.37

0.50

5.80

0.69

13.6

70.

824.

140.

112.

510.

044.

390.

038.

620.

077.

420.

146.

700.

126.

130.

089.

400,

21

CASA

REAL

C.Sa

uvi

gñon

A0

15.5

40.

9111

.04

0.78

11.0

40.

7119

.02

0.94

9.52

0.18

7.01

0.06

6.34

0.12

8.35

0.05

16.6

00.

4212

.07

0.30

10.4

90.

1615

.21

0,15

A1

15.4

85.

478.

780.

8510

.15

1.16

16.6

00.

749.

930.

337.

900.

047.

840.

129.

450.

1116

.93

0.39

13.9

10.

2113

.59

0.16

14.4

40,

23

A2

13.0

40.

7811

.86

0.80

12.3

00.

4822

.80

1.58

8.02

0.34

5.42

0.04

7.28

0.11

8.41

0.03

12.4

00.

9711

.32

0.41

12.1

00.

1613

.89

0,15

CO

NCEPCIO

NC.Sa

uvi

gñon

A0

ND

ND

ND

ND

6.24

0.68

18.2

21.

42N

DN

DN

DN

D5.

180.

058.

430.

03N

DN

DN

DN

D7.

940.

0611

.04

0,16

A1

ND

ND

ND

ND

13.2

30.

4318

.29

0.81

ND

ND

ND

ND

6.75

0.10

7.84

0.03

ND

ND

ND

ND

9.08

0.12

11.0

00,

13

A2

ND

ND

ND

ND

9.37

0.41

16.3

40.

99N

DN

DN

DN

D5.

230.

05N

DN

DN

DN

DN

DN

D8.

980.

088.

220,

15

Ran

ge4.

40–1

5.54

8.37

–13.

855.

80–1

3.23

13.6

7–22

.84.

14–9

.93

2.51

–7.9

04.

39–7

.84

1.08

–9.4

57.

42–1

6.93

6.49

–17.

876.

13–1

3.59

8.22

–15.

21

Mea

n11

.56

10.1

99.

2017

.57

7.87

5.80

5.96

7.47

12.5

210

.76

8.84

11.5

0

A0:

No

atte

nuat

ion;A1:

20%

ofU

V-B

atte

nuat

ion

usi

ng

abla

ckan

tihai

lnet

;A2:

60%

ofa

UV-B

atte

nuat

ion

usi

ng

aye

llow

250-

nm

poly

este

rfilte

r.

320

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

Resveratrol in Bolivian High Valley Grapes 321

TABLE 4 Temporal Evolution of trans-Resveratrol in Grape Skins Expressed as ResveratrolContent µg/g (dm); (I) 9 Feb.; (II): 22 Feb.; (III): 4 Mar.; and (IV): 22 Mar. 2011

Vineyard Cultivar CodeResveratrol

(I)Resveratrol

(II)Resveratrol

(III)Resveratrol

(IV) Mean

CENAVIT Cariñena(black)

A0 515 647 514 128 451

A1 250 404 248 245 278A2 750 80 688 318 441

KOHLBERG Syrah A0 505 931 924 53 603A1 42 845 466 281 409A2 390 727 1161 183 615

CASA REAL C. Sauvigñon A0 72 365 223 82 186A1 114 255 165 205 185A2 111 303 157 51 156

CONCEPCION C. Sauvigñon A0 nd nd 255 97 176A1 nd nd 193 113 153A2 nd nd 43 48 239

Mean 302 498 505 172 324

A0: No attenuation; A1: 20% of UV-B attenuation using a black anti hail net; A2: 60% of a UV-B attenuationusing a yellow 250-nm polyester filter; nd = not determined.

The TAC values show a small decrement during the II and III collectionscompared to the first (I) and an increment in the last collection (IV) as seenin Table 3. The same behavior is observed for total phenolic content. Thevalues obtained in the present research were higher in comparison to thosereported in the literature (Lutz et al., 2011; Anastasiadi et al., 2010).

HPLC Measurements

Trans-resveratrol was identified and quantified by RP-HPLC (Fig. 3); themethod has been previously used for the determination of phenolic com-pounds in food and other extracts (Peñarrieta et al., 2008, 2009, 2011;Carrasco et al., 2011, 2012).

To facilitate the comparison with literature data, trans-resveratrol wasmeasured in grape skins in samples collected at both locations (Loayza andCercado valleys). The values are summarized in Tables 2 and 4, expressedas µg/g of dry weight. The trans-resveratrol content of black grapes variedfrom 10 to 80 µg/g in the samples collected in the Loayza province (La Paz),while in the Cercado province (Tarija) they varied from 42 to 1100.

DISCUSSION

Samples Collected in Luribay Valleys

The values of TAC showed to be homogeneous when the extracts wereobtained from grape pulps, while the values obtained from grape skins

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

322 M. Taquichiri et al.

FIGURE 3 Separation of trans-resveratrol in grape samples and the standard with theircorresponding online UV-visible spectra.

showed higher variation among samples. This indicates that the distribu-tion of antioxidants varies significantly in the grape skins. Also, when thedata from grape skins is plotted in logarithmic scale it is possible to observetwo clusters (Fig. 2). This implies that grapes can be separated in groupsaccording to their antioxidant composition in the skin.

Regarding the content of trans-resveratrol and its relation with UV expo-sure in the samples collected at Loayza province, higher values of thiscompound would be expected than those obtained from Tarija valleys; how-ever, the range was lower. A possible explanation is that these grapes receiveless sunlight and are not cultivated under controlled conditions. They areproduced for the local market without any particular selection or pruning incontrast with practices in Tarija. In addition, the local conditions are differentin the Loayza province (for example, a scarcity of water and the reposition ofnutrients in the land). We conclude that UV exposure it is not enough for theincrement of resveratrol at high altitude. The amounts of trans-resveratrol inthe grapes from Loayza province were in the same range as grape cultivars atsea level (Pascual-Martí et al., 2011; Li et al., 2006; Cantos et al., 2000; Morenoet al., 2008) and even comparable with an investigation where grapes wereirradiated with UV(Moreno et al., 2008; Cantos et al., 2006).

Samples Collected in Cercado Valleys

As explained in the experimental section, three different UVB attenuationswere carried out in grape cultivars. The samples were collected at differentstates of maturation (from veraison to harvest) to observe the evolution ofantioxidants and trans-resveratrol content during the growing of the grapes.

The results show an increment in TAC, TPH, and trans-resveratrol inmost of the cultivars when solar UVB was 20% attenuated in comparison

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

Resveratrol in Bolivian High Valley Grapes 323

with the other setups, and a decrement of resveratrol over in time (Table 4).An explanation is that the content of trans-resveratrol in grapes tends todecrease during maturation (Jeandet et al., 1991) and we can assume thatthe UVR attenuation may delay this process keeping high levels of trans-resveratrol in the fruits. In some cases, the values vary considerably amongsamples while in others they remain almost constant reflecting the naturalvariability of phenolic compounds in plants.

The most interesting result is that the mean values of trans-resveratrolobtained in the samples collected in the Tarija region were almost 10-foldhigher than the samples collected in the Loayza province and also from thosereported in the literature in skin grapes collected from different regions of theworld (Pascual-Martí et al., 2011; Li et al., 2006; Cantos et al., 2000; Morenoet al., 2008). In addition, the Syrah cultivar showed the highest values oftrans-resveratrol and we can assume that this cultivar is more affected byUVR exposure.

CONCLUSIONS

The higher values of trans-resveratrol obtained in grapes from Tarija suggestthat selected grape cultivars growing at high altitude and in a particular atlatitudes such as those of the high mountain valleys of Tarija can metabolizehigher amounts of resveratrol even when solar UVR is partially attenuated.In future studies, the metabolic rates, due to the UVA, need to be assessedsince UVA correlates with sugar formation in plants (Table 1). Also, thedevelopment of antioxidants in the fruit needs to be further investigatedas UVA is related to oxidation processes while UVB is related to metabolicchanges.

The present investigation is set out to demonstrate the influence of solarUVR under the local climate and geographical conditions in which grapes areproduced in the Bolivian valleys today. Given our results, described above,it is necessary to develop more stringent protocols regarding the collectionof the grapes especially those subject to attenuation.

The lower values of trans-resveratrol measured in the samples collectedin the Luribay valleys compared with those from Tarija show that apart fromhigh levels of UVR, it is important to control other factors that could influencetrans-resveratrol values, such as the quality of cultivars, the selection andpruning of plants, and their water irrigation.

South America is considered a major protagonist in the internationalwine industry. Nowadays, the term high altitude wines has become popularas an indicator of quality, in particular those produced in the Cafayate regionof Argentina (The Miami Herald, 2012). Inter Andean valleys, such as Tarija,have the potential to become players in this niche market of wines madefrom selected grapes grown at high altitude. The amounts of trans-resveratrol

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

324 M. Taquichiri et al.

measured in the present investigation relate to grapes and similar studiesneed to be done to confirm that these high levels are also present in thewines produced in the Tarija and other valleys at high altitude. If so, trans-resveratrol could be considered a chemical marker for the definition of highaltitude grapes and wines.

Furthermore, it is important to note that this is the first time that thedose of UVA has been measured in situ in Bolivian vineyards and we suspectthat UVA is even more important than UVB for resveratrol production. Morestudies are needed to explain this difference.

FUNDING

This study was supported by the Swedish International Development Agency(SIDA) under the agreement with UMSA and the Bolivian Governmentthrough the IDH projects.

LITERATURE CITED

Anastasiadi, M., H. Pratsinis, D. Kletsas, A. Skaltsounis, and S. Haroutounian. 2010.Bioactive noncoloured polyphenols content of grapes, wines and vinificationby-products: Evaluation of the antioxidant activities of their extracts. Food Res.Int. 43:805–813.

Brosché, M. and A. Strid. 2003. Molecular events following perception of ultraviolet-Bradiation by plants. Physiol. Plant. 117:1–10.

Cantos, E. and T. Barberan. 2001. Postharvest induction modeling method using UVirradiation pulses for obtaining resveratrol-enriched table grapes. J. Agric. FoodChem. 49:5052–5058.

Cantos, E., C. García-Viguera, S. de Pascual-Teresa, and F.A. Tomás-Barberán. 2000.Effect of postharvest ultraviolet irradiation on resveratrol and other phenolics ofcv. Napoleon table grapes. J. Agric. Food Chem. 48:4606–4612.

Cantos, E., J.C. Espín, M.J. Fernández, J. Oliva, and F.A. Tomás-Barberán. 2006.Postharvest UV-C-irradiated grapes as a potential source for producing stilbene-enriched red wines. J. Agric. Food Chem. 51:1208–1214.

Carrasco, C., C. Solano, J.M. Peñarrieta, E.M. Baudel, M. Galbe, and G. Lidén.2012. Arabinosylated phenolics obtained from SO2-steam-pretreated sugarcanebagasse. J Chem. Technol. Biot. 87:1723–1725.

Carrasco, C., H. Baudel, J.M. Peñarrieta, S. Solano, L. Tejeda, C. Roslander, M. Galbe,and G. Lidén. 2011. Steam pretreatment and fermentation of the straw material“Paja Brava” using simultaneous saccharification and co-fermentation. J. Biosci.Bioeng. 111:167–174.

Halvorsen, B.L., K. Holte, M.C.W. Myhrstad, I. Barikmo, E. Hvattum, S.V. Remberg,A.B. Wold, K. Haffner, H. Baugerod, L.N. Andersen, J.O. Moskaug, D.R. JacobsJr., and R. Blomhoff. 2002. A systematic screening of total antioxidants in dietaryplants. J. Nutr. 132:461–471.

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

Resveratrol in Bolivian High Valley Grapes 325

Jeandet, P., R. Bessis, and B. Gautheronondré. 1991. The production of resveratrol(3,5,4′-trihydroxystilbene) by grape berries in different developmental stages.Am. J. Enol. Vitic. 42:41–46.

Krzscin, J.W. 2000. Impact of the ozone profile on the surface UV radiation: Analysesof the Umkehr and UV measurements at Belsk (52◦ N, 21◦ E), Poland. J.Geophys. Res. 105:2009–2015.

Li, X., B.Wu, L. Wang, and L. Shaohua. 2006. Extractable amounts of trans-resveratrolin seed and berry skin in vitis evaluated at the germplasm level. China J. Agric.Food Chem. 23:8804–8811.

Lobato, A. and S. Prudencio. 2012. Analysis of table grape production in Bolivia.Market Access and Poverty Alleviation Project. March 2012. <http://pdf.usaid.gov/pdf_docs/PNADA764.pdf>.

Lutz, M., K. Jorquera, B. Cancino, and C. Hernriquez. 2011. Phenolics and antioxidantcapacity of table grape (Vitis vinifera L.) cultivars grown in Chile. J. Food. Sci.76:C1088–C1093.

Madronich, S., R.L. McKenzie, L.O. Björn, and M.M. Caldwell. 1988. Changes bio-logically active ultraviolet radiation reaching the Earth’s surface. J. Photochem.Photobiol. 46:5–19.

Moreno, A., M. Castro, and E. Falqué. 2008. Evolution of trans- and cis-resveratrolcontent in red grapes (Vitis vinifera L. cv Mencía, Albarello and Merenzao)during ripening. Eur. Food Res. Technol. 227:667–674.

Nilsson, J., D. Pillai, G. Önning, C. Persson, Å. Nilsson, and B. Åkesson. 2005.Comparison of the ABTS and FRAP methods to assess the total antioxidantcapacity in extracts of fruit and vegetables. Mol. Nutr. Food Res. 49:239–246.

Parrish, J.A., K.F. Jaenicke, and R.P. Anderson. 1992. Erythema and melanogenesisaction spectra of normal human skin. Photochem. Photobiol. 36:187–191.

Pascual-Martí, M.C., A. Salvador, A. Chafer, and A. Berna. 2011. Supercritical fluidextraction of resveratrol from grape skin from Vitis vinifera and determinationby HPLC. Talanta 54:735–740.

Peñarrieta, J.M., J.A. Alvarado, B. Åkesson, and B. Bergenståhl. 2008. Totalantioxidant capacity and content of flavonoids and other phenolic compoundsin Canihua (Chenopodium pallidicaule): An Andean pseudocereal. Mol. Nutr.Food Res. 52:708–717.

Peñarrieta, J.M., J.A. Alvarado, B. Bergenståhl, and B. Åkesson. 2009. Totalantioxidant capacity and content of phenolic compounds in wild strawberries(Fragaria vesca) collected in Bolivia. Int. J. Fruit Sci. 9:344–359.

Peñarrieta, J.M., T. Salluca, L. Tejeda, J.A. Alvarado, and B. Bergenståhl. 2011.Changes in phenolic antioxidants during Chuño production (traditional Andeanfreeze and sun-dried potato). J. Food Comp. Anal. 24:580–587.

Pfeifer, M., P. Koepke, and J. Reuder. 2006. Effects of altitude and aerosols on UVradiation. J. Geophys. Res. 111:D01203. DOI 10.129/2005JD006444.

Potrebko, I. and A.V. Resurrection. 2009. Effect of ultraviolet doses in combinedultraviolet-ultrasound treatments on trans-resveratrol and trans-piceid contentsin sliced peanut kernels. J. Agric. Food Chem. 57:7750–7756.

Saura-Calixto, F., and I. Goñi. 2006. Antioxidant capacity of the Spanish Mediterr-anean diet. Food Chem. 94:442–447.

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014

326 M. Taquichiri et al.

Stervbo, U., O.Vang, and C. Bonneses. 2007. Review of the content of the putativechemopreventive phytoalexin resveratrol in red wine. Food Chem. 101:449–457.

Taquichiri, M., and J. Paco. 2008. Determinación del Índice de la radiaciónultravioleta en la ciudad de tarija. Innovación 1:28–29.

Tevini, M., and A.H. Teramura. 1989. Uv-B effects on terrestrial plants. Photochem.Photobiol. 50:479–487.

The Miami Herald. High altitude wines gain color, flavor. 16 Feb. 2012. http://www.miamiherald.com/2012/02/16/2642847/high-altitude-wines-gain-color.html

Tórrez, R. 2004. La radiación ultravioleta B difusa. Mediciones en cota-cota, La Paz(3420 msnm). Revista Boliviana de Física 10:24.

Yang, C., J. Landau, M. Huang, and H. Newmark. 2000. Inhibition of carcinogenesisby dietary polyphenolic compounds. Annu. Rev. Nutr. 21:381–406.

Zaratti, F., R.N. Forno, J. García Fuentes, and M.F. Andrade. 2003. Erythemallyweighted UV variations at two high-altitude locations. J. Geophys. Res.108(D9):4263. DOI 10.1029/2001JD000918.

Dow

nloa

ded

by [

Que

ensl

and

Uni

vers

ity o

f T

echn

olog

y] a

t 12:

54 2

1 N

ovem

ber

2014