Phenolic Profile Characterization of ‘Galega vulgar’ and ‘Cobrançosa’

Portuguese Olive Cultivars along the Ripening StagesMiguel Ferro1,2, Elsa Lopes3,4, Marta Afonso1, Augusto Peixe5, Francisco M. Rodrigues3,6, Maria F. Duarte1,2*

Portuguese Olive Cultivars along the Ripening StagesMiguel Ferro1,2, Elsa Lopes3,4, Marta Afonso1, Augusto Peixe5, Francisco M. Rodrigues3,6, Maria F. Duarte1,2*1Centro de Biotecnologia Agrícola e Agro-Alimentar do Alentejo (CEBAL)/Instituto Politécnico de Beja (IPBeja), 7801-908 Beja, Portugal; 2MED—Mediterranean Institute for Agriculture, Environment and Development, CEBAL, 7801-908 Beja, Portugal3PolytechnicInstituteof Portalegre, Portugal, 7300-110 Portalegre, Portugal;PolytechnicInstituteof Portalegre, Portugal, 7300-110 Portalegre, Portugal;4Departamento de Fisiologia Vegetal, Universidade da Extremadura, Av. de Elvas, 06006 Badajoz, Espanha5MED—Mediterranean Institute for Agriculture, Environment and Development & Departamento de Fitotecnia, Escola de Ciências e Tecnologia, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal; 6MED—Mediterranean Institute for Agriculture, Environment and Development, Universidade de Évora, Pólo da Mitra, Ap. 94, 7006-554 Évora, Portugal*fatima.duarte@cebal.pt;

INTRODUCTION

fatima.duarte@cebal.pt;

www.cebal.pt

INTRODUCTIONOleuropein (OLE) represents the major phenolic compound (PC) found in olive fruit, ranging from a wide spectrum of concentrations. The presence of this specific and unique PC in olive fruit,

as well as their degradation derivatives, has been widely studied and their strong antioxidant activity reported[1], which possesses great health benefits upon its regular consuption[2–3]. Virgin

olive oil (VOO) phenolic profile is mainly derived from the amount of phenolic glycosides originally found in olive fruit, as well the activity of specific oxidative and hydrolytic enzymes duringolive oil (VOO) phenolic profile is mainly derived from the amount of phenolic glycosides originally found in olive fruit, as well the activity of specific oxidative and hydrolytic enzymes during

VOO processing[4], such as the highly specific β-glucosidases. The specific presence and abundance of olive fruits PCs has been proved to be cultivar specific[5], as well as ripening related[6].

Regarding traditional Portuguese olive cultivars, such as ‘Galega vulgar’ and ‘Cobrançosa’, not much information is available, in terms of phenolic profile along ripening.

AIM: To evaluate the phenolic profile of ‘Galega vulgar’ and ‘Cobrançosa’ cultivars along their ripening stages

Regarding traditional Portuguese olive cultivars, such as ‘Galega vulgar’ and ‘Cobrançosa’, not much information is available, in terms of phenolic profile along ripening.

AIM: To evaluate the phenolic profile of ‘Galega vulgar’ and ‘Cobrançosa’ cultivars along their ripening stages

RESULTS & DISCUSSIONRESULTS & DISCUSSION

OLIVE SAMPLE COLLECTION OLEUROPEIN CONCENTRATION OVER MI AND OPDWOLIVE SAMPLE COLLECTION OLEUROPEIN CONCENTRATION OVER MI AND OPDW

Sampling Reference Date Cultivar

S1 12-09-2019 Gal + Cob

S2 26-09-2019 Gal + Cob

‘Cobrançosa’ showed block I topresent the highest OLES2 26-09-2019 Gal + Cob

S3 10-10-2019 Gal + Cob

S4 24-10-2019 Gal + Cob

S5 07-11-2019 Gal + Cob

present the highest OLEconcentrations at S6, with more than6,000 mg/Kg;

S5 07-11-2019 Gal + Cob

S6 20-11-2019 Gal (harvesting day)

S6 04-12-2019 Cob (harvesting day)

Temporal distribution of sampling dates for each cultivar, ‘Galega Vulgar’ (Gal) and ‘Cobrançosa’ (Cob).

6,000 mg/Kg;

Within all ‘Galega vulgar’ samplingblocks a positive OLE peak andmaximum, was registered at S3, withTemporal distribution of sampling dates for each cultivar, ‘Galega Vulgar’ (Gal) and ‘Cobrançosa’ (Cob).

OLIVE SAMPLE CHARACTERIZATION

Cultivar OPDW (%) MI HT OLE

maximum, was registered at S3, withblock III showing the highest amountwith 35,000 mg/Kg;

Cultivar Ripening Stage OPDW (%) MI HT OLE

S1 18.74 ± 0.18a 0.070 ± 0.030a 105 ± 24a 1,236 ± 684a

S2 26.20 ± 0.54b 0.88 ± 0.02b 108 ± 11a 1,689 ± 880a,c

with 35,000 mg/Kg;

For both cultivars, MI showed its mostsignificant increase when OLE

‘Cobrançosa’

S2 26.20 ± 0.54 0.88 ± 0.02 108 ± 11a 1,689 ± 880a,c

S3 29.56 ± 0.26c 1.03± 0.07c 118 ± 23a,b 1,619 ± 527a,c

S4 32.45 ± 0.11d 1.24± 0.11d 130 ± 35a,b,c 1,790 ± 1084a,c

S5 36.27 ± 0.66e 2.16 ± 0.23e 157 ± 46c,d 1,387 ± 652a

significant increase when OLEconcentration was at its maximumaccumulation;

Ripening stage (S) profile of oleuropein (OLE) concentration regarding maturity index (MI) for ‘Cobrançosa’ (A) and ‘Galegavulgar’ (B) over four different sampling blocks (Blocks I to IV).

157 ± 46 1,387 ± 652S6 38.65 ± 0.72f 3.16 ± 0.17f 156 ± 46b,d 3,268 ± 2.731b,c

S1 26.920 ± 0.042A 0.090 ± 0.030A 98 ± 30A 16,763 ± 15.173A,B

S2 28.83 ± 0.20B 1.50 ± 0.20B 93 ± 22A 7,976 ± 1.867B

S3 34.59 ± 0.25C 3.670± 0.070C

Regarding ‘Cobrançosa’, OPDWmaximum values occured at S6 in

‘Galega Vulgar’S3 34.59 ± 0.25C 3.670± 0.070C 71 ± 28B 26,304 ± 10.930A

S4 30.86 ± 0.86D 3.900± 0.030D 61 ± 30B 4,141 ± 1.338C

S5 34.69 ± 0.81C 3.990± 0.010E 82 ± 28A,B 1,582 ± 115D

S6 34.28 ± 0.63C 4.040± 0.030F 126 ± 31C 1,908 ± 468E maximum values occured at S6 in

agreement with the general maximum

OLE concentration registered for this

Evaluation of olive fruit fat content in dry matter (OPDW) and maturity index (MI), as well as quantification of hydroxytyrosol(HT) and oleuropein (OLE) along ripening (S), for ‘Cobrançosa’ and ‘Galega vulgar’( mean ± standard deviation).

a, b, c, d, e and f: Mean values of ‘Cobrançosa’ cultivar with a different superscript differ significantly (P-value< 0.05)

S6 34.28 ± 0.63C 4.040± 0.030F 126 ± 31C 1,908 ± 468E

‘Cobrançosa’ presented highest OPDW at harvest time, showing a different behavior from

‘Galega vulgar’ which presented higher OPDW values at na earlier ripening stage;

OLE concentration registered for thiscultivar;

For ‘Galega vulgar’ most relevant

a, b, c, d, e and f: Mean values of ‘Cobrançosa’ cultivar with a different superscript differ significantly (P-value< 0.05)(comparison between ripening stages); for ‘Galega vulgar’ capital letters were used.

‘Galega vulgar’ which presented higher OPDW values at na earlier ripening stage;

In agreement with OPDW, for both cultivars, highest MI increase was achieved when oil

content was at its maximum accumulation;

OPDW increase was reached at S3,

coincident also with highest OLE

concentrations for all blocks.content was at its maximum accumulation;

Both cultivars presented quite distinct kinetics in regard to MI and OPDW, with ‘Galega

Vulgar’ reaching considerably high OPDW and MI at a much earlier ripening stage;

concentrations for all blocks.

Vulgar’ reaching considerably high OPDW and MI at a much earlier ripening stage;

Both cultivars registered higher HT at a latter ripening. Since HT mainly results from an

enzymatic hydrolysis of OLE, the increase of HT towards harvest could be expected;

OLE was registered with its higher amounts at S6 for ‘Cobrançosa’ and S3 for ‘Galega

Vulgar’Ripening stage (S) profile of oleuropein (OLE) concentration regarding fat content in dry matter (OPDW) for ‘Cobrançosa’

(C) and ‘Galega vulgar’ (D) over four different sampling blocks (Blocks I to IV).

REFERENCES:

ACKNOWLEDGMENTS:

ConclusionsConclusions: For both ‘Cobrançosa’ and ‘Galega Vulgar’ different harvesting periods should

REFERENCES:

[1] Benavente-García, O. et al. leaves. Food Chem.2000, 68, 457–462, doi:10.1016/S0308-8146(99)00221-6.[2] Coni, E. et al. Lipids2000, 35, 45–54, doi:10.1007/s11745-000-0493-2.[3] Visioli, F. et al. Biochem. Biophys. Res. Commun.1998, 247, 60–64, doi:10.1006/bbrc.1998.8735.

[4] Velázquez-Palmero, D. et al. Front. Plant Sci.2017, 8, 1–12, doi:10.3389/fpls.2017.01902.[5] Brenes, M. et al. J. Agric. Food Chem.1999, 47, 3535–3540, doi:10.1021/jf990009o.[6] Conde, C. et al. J. Plant Physiol.2008, 165, 1545–1562, doi:10.1016/j.jplph.2008.04.018.

ACKNOWLEDGMENTS:

This work was supported by the Program Alentejo 2020, through the European Fund for Regional Development (FEDER) under the scope of OleaValor – Valorização das Variedades de Oliveira Portuguesas

(ALT20-03-0145-FEDER-000014).

This work was also funded through FCT under the Project UIDB/05183/2020 to Mediterranean Institute for Agriculture, Environment and Development (MED).

Authors also acknowledge FCT for PhD grant to Miguel Ferro (SFRH/BD/140083/2018). Authors are grateful to Torre das Figueiras—Sociedade Agrícola (Monforte, Portugal) for allowing olive fruits

collection.

For both ‘Cobrançosa’ and ‘Galega Vulgar’ different harvesting periods should

be considered;

‘Cobrançosa’ presented the optimal harvest period at S6, when both MI and

OPDW were at their maximum and OLE accumulation also showed ancollection.

OPDW were at their maximum and OLE accumulation also showed an

increasing trend;

‘Galega vulgar’ presented its optimal harvest period at S3, when most

significant MI increase was registered and also the highest OPDW and OLEOLEAVALOR

ALT20-03-0145-FEDER-000014

significant MI increase was registered and also the highest OPDW and OLE

accumulation were reached.