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Journal of Arid Land  2022, Vol. 14 Issue (10): 1159-1179    DOI: 10.1007/s40333-022-0078-9
Research article     
Leaf morpho-physiology and phytochemistry of olive trees as affected by cultivar type and increasing aridity
Said TOUATI1, Jawaher AYADI1, Abdelhakim BOUAJILA2, Smail ACILA3, Rami RAHMANI1, Jalloul BOUAJILA4, Mohamed DEBOUBA1,*()
1Laboratory of "Biodiversity, Molecule and Applications, LR22ES02", Higher Institute of Applied Biology of Medenine, University of Gabes, Zrig 6029, Tunisia
2Laboratory of Geosystems, Georessources and Geoenvironments, Faculty of Science of Gabes, Department of Earth Sciences, University of Gabes, Zrig 6029, Tunisia
3Laboratory of Biology, Environment and Health, Department of Biology, Faculty of Nature and Life Sciences, University of Echahid Hamma Lakhdar El-Oued, Chott 39000, Algeria
4Laboratoire de Génie Chimique, Université de Paul Sabatier, CNRS, INPT, UPS, Toulouse, France
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The olive species (Olea europaea L.) is an ancient traditional crop grown under rainfed conditions in the Mediterranean Basin. In response to the growing national and international demand for olive oil, the olive cultivars are introduced into highly arid new bioclimatic areas. Subsequently, the morpho-physiology and phytochemistry of olive trees are potentially changing among cultivar types and geographical conditions. In the present work, we have undertaken an assessment on the impacts of geographical location and cultivar types on the leaf morpho-physiology and phytochemistry of olive trees. Thus, leaves of the two most cultivated olive tree varieties, Chemlal and Sigoise, were collected from three geographical regions (Setif, Batna, and Eloued) with increasing aridity in Algeria. Leaf samples from the geographical regions were analyzed using the standard physiological experiment, colorimetric method, and a chromatography assay. Leaves of both cultivars exhibited a significant variance in terms of the leaf shape index but not for the leaf tissue density, specific leaf weight, and specific leaf area. Photosynthetic pigment contents were affected by both cultivar type and geographical location, with the lowest pigment content recorded in the Sigoise cultivar from the Setif region. Compared with the Setif and Batna regions, dried leaves of both cultivars from the Eloued region showed the higher levels of the total polyphenol, total flavonoid, and total tannin, as well as a better antioxidant capacity. Liquid chromatography-mass spectrometry analysis of all leaf extracts identified the following phenolic acids as major compounds: oleuropein, naringin, apigenin-7-O-glucoside, kaempferol, quercetin, quercitrin, luteolin-7-O-naringenin, and quinic acid. Lower contents were found for p-Coumaric acid, trans-Ferulic acid, hyperoside, rutin, apigenin, caffeic acid, protocatechuic acid, o-Coumaric acid, and gallic acid. Also, epicatechin and catechin+ were not found in the leaf extracts of the Sigoise cultivar. The leaf organic extracts in both cultivars displayed promising anti-cancer activity that was affected by geographical location and organic solvent polarity. Briefly, although increasing aridity and soil organic and mineral deficiency affected the leaf morpho-physiological parameters, both cultivars sustained a chemical richness, a good antioxidant, and an anti-tumoral capacity in leaves. Furthermore, the findings revealed that regardless the olive tree genotype, there was a significant impact of geographical location on the leaf morpho-physiology, bioactivity, and chemical composition, which may consequently modulate the growth and oil production of olive trees.

Key wordsOlea europaea L.      aridity      leaf morpho-physiology      bioactivity      olive cultivar      geographical location      Algeria     
Received: 26 April 2022      Published: 31 October 2022
Corresponding Authors: *Mohamed DEBOUBA (E-mail:
Cite this article:

Said TOUATI, Jawaher AYADI, Abdelhakim BOUAJILA, Smail ACILA, Rami RAHMANI, Jalloul BOUAJILA, Mohamed DEBOUBA. Leaf morpho-physiology and phytochemistry of olive trees as affected by cultivar type and increasing aridity. Journal of Arid Land, 2022, 14(10): 1159-1179.

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Fig. 1 Climatic conditions of the three geographical regions in Algeria (Setif, Batna, and Eloued)
Parameter Sigoise cultivar Chemlal cultivar ANOVA (P value)
Setif Batna Eloued Setif Batna Eloued Geographical
pH 8.11±0.09b 7.74±0.19c 7.53±0.11d 8.39±0.02a 8.10±0.03b 7.78±0.17c 0.000*** 0.000*** 0.755
EC (mS/cm) 0.13±0.01d 0.85±0.05c 1.23±0.19b 0.10±0.01d 1.59±0.11a 1.17±0.04b 0.000*** 0.000*** 0.000***
SOC (%) 0.95±0.04a 0.26±0.03d 0.13±0.01e 0.69±0.04c 0.77±0.03b 0.11±0.00e 0.000*** 0.000*** 0.000***
CaCO3 (%) 11.45±1.54b 20.87±5.83a 7.41±0.58b 9.09±2.67b 20.54±1.17a 7.41±0.57b 0.000*** 0.503 0.732
Clay (%) 31.0b 16.5d 1.1f 33.8a 23.3c 2.5e
Silt (%) 43.2a 17.1d 3.2e 22.1c 27.5b 2.8f
Sand (%) 25.8f 66.4c 95.7a 44.1e 49.2d 94.7b
Soil texture Clay loam Sandy loam Sand Clay loam Sandy clay loam Sand
Table 1 Main properties of soils collected from Sigoise and Chemlal cultivated lands in the three different geographical regions (Setif, Batna, and Eloued)
Table 2 Morpho-physiological, pigment, and pbryto-chemical contents in the olive leaves collected from the Sigoise and Chemlal cultivated lands in the three different geographical regions (Setif, Batna, and Eloued)
Class Phenolic compound Sigoise cultivar
Setif Batna Eloued Setif Batna Eloued Setif Batna Eloued
Oleuropeosid Oleuropein (mg/kg) 0.44 0.94 2.46 186.93 576.90 257.02 10,664.70 15,900.86 13,516.76
Galic acid (mg/kg) 2.28 nd nd nd nd nd nd nd 12.86
Protocatechuic acid (mg/kg) nd nd nd nd nd nd nd 73.49 nd
Caffeic acid (mg/kg) nd nd nd nd 10.30 nd nd nd nd
Paracoumaric acid (mg/kg) nd nd nd 5.09 nd nd nd 9.22 10.93
Trans-Ferulic acid (mg/kg) nd nd nd 1.35 nd 3.08 12.77 12.76 6.21
O-coumaric acid (mg/kg) nd nd nd 2.71 nd nd nd nd nd
Quinic acid (mg/kg) nd nd 0.31 2.41 2.60 5.71 1441.64 846.43 977.42
Flavones Luteolin-7-O-glucoside (mg/kg) 0.17 nd 0.01 0.33 nd 0.47 1165.99 1127.62 1502.89
Apegenin-7-O-glucoside (mg/kg) nd nd nd 0.28 0.11 0.08 71.82 78.92 85.29
Apigenin (mg/kg) nd nd nd nd 0.16 nd 7.07 4.96 4.93
Flavonols Rutin (mg/kg) nd nd nd nd nd nd 347.24 284.98 759.05
Hyperoside (mg/kg) nd nd nd nd nd nd 32.60 25.28 70.29
Quercitrin (mg/kg) 0.16 nd nd nd nd 0.2 736.90 752.38 1102.14
Kaempferol (mg/kg) nd 0.24 0.03 0.16 0.11 nd 49.25 50.57 54.65
Quercetin (mg/kg) 1.56 1.90 0.59 nd 1.36 nd 109.9 60.73 169.51
Flavan3-ols Catechin+ (mg/kg) nd nd nd nd nd nd nd nd nd
Epicatechin (mg/kg) nd nd nd nd nd nd nd nd nd
Flavanones Naringin (mg/kg) nd nd nd 2.93 6.12 7.67 38.99 48.91 59.79
Naringenin (mg/kg) nd 0.05 0.05 0.39 0.60 0.29 1.60 1.65 2.57
Total 4.61 3.13 3.45 202.58 598.26 274.52 14,680.47 19,278.76 18,335.29
Table 3 Liquid chromatography-mass spectrometry analysis of phenolic compounds extracted using organic solvents (hexane, DCM, and MeOH) in leaves of Sigoise cultivar in the three different geographical regions (Setif, Batna, and Eloued)
Class Phenolic compound Chemlal cultivar
Setif Batna Eloued Setif Batna Eloued Setif Batna Eloued
Oleuropeosid Oleuropein (mg/kg) 1.25 0.88 0.54 1057.86 266.19 263.87 10,205.12 13,080.86 15,718.02
Phenolic acids Hydroxybenzoic
Galic acid (mg/kg) nd nd nd nd nd nd nd nd 38.15
Protocatechuic acid
nd nd nd nd nd nd nd 74.44 244.16
Caffeic acid (mg/kg) nd nd nd nd nd nd 3.66 nd nd
Paracoumaric acid
nd nd nd nd nd nd 24.66 39.15 16.57
Trans-Ferulic acid
nd nd nd 11.73 3.33 nd 17.09 11.21 5.67
O-coumaric acid
nd nd nd nd nd nd nd nd 4.36
Cyclohexanecarboxylic acids Quinic acid (mg/kg) nd nd nd 4.16 19.15 nd 674.48 885.36 1688.85
Flavones Luteolin-7-O-glucoside
0.14 nd nd nd 0.003 1.31 1384.37 1396.51 1774.30
nd 0.05 0.01 0.95 0.59 0.35 65.69 97.97 90.69
Apigenin (mg/kg) nd nd nd 0.76 nd 0.13 3.91 4.41 4.14
Flavonols Rutin (mg/kg) nd nd nd nd nd nd 632.97 446.08 749.27
Hyperoside (mg/kg) nd nd nd nd nd nd 34.43 32.35 69.54
Quercitrin (mg/kg) nd nd nd nd 0.23 0.54 1003.42 1015.5 1008.25
Kaempferol (mg/kg) nd nd 0.01 0.28 0.03 0.16 68.86 65.07 51.67
Quercetin (mg/kg) nd 2.38 2.01 nd nd 0.99 65.69 158.80 227.37
Flavan3-ols Catechin+ (mg/kg) nd nd nd nd nd nd 4.88 nd nd
Epicatechin (mg/kg) nd nd nd nd 4.30 nd 2.93 nd nd
Flavanones Naringin (mg/kg) nd nd nd 19.25 nd 3.70 47.62 61.94 72.16
Naringenin (mg/kg) 0.25 nd nd 0.57 8.04 0.32 1.47 5.88 2.40
Total 1.64 3.31 2.57 1095.56 301.86 271.37 14,241.25 17,375.53 21,765.57
Table 4 Liquid chromatography-mass spectrometry analysis of phenolic compounds extracted using organic solvents (hexane, DCM, and MeOH) in leaves of Chemlal cultivar in the three different geographical regions (Setif, Batna, and Eloued)
Fig. 2 Liquid chromatography-mass spectrometry analysis on the contents of the phenolic compounds in olive leaves of the Sigoise cultivar (a) and Chemlal cultivar (b) in the three different geographical regions (Setif, Batna, and Eloued)
Fig. 3 Changes in the anti-HCT116 (a) and anti-Caco-2 (b) activities of the olive leaf extracts using organic solvents (hexane, dichloromethane (DCM), and methanol (MeOH)) in the Sigoise and Chemlal cultivars in the three different geographical regions (Setif, Batna, and Eloued). Different lowercase letters indicate significantly different values at P≤0.05 level according to the Fisher's LSD test.
Factor P value
Anti-HCT116 Anti-Caco-2
Cultivar type 0.001** 0.000***
Geographical location 0.000*** 0.000***
Solvents 0.000*** 0.000***
Cultivar type×Geographical location 0.061 0.000***
Cultivar type×Solvents 0.527 0.000***
Geographical location×Solvents 0.000*** 0.000***
Cultivar type×Geographical location×Solvents 0.002** 0.000***
Table 5 Results of P values and the related significance levels for the anti-HCT116 and anti-Caco-2 activities of the olive leaf extracts using organic solvents (hexane, DCM, and MeOH) in the Sigoise and Chemlal cultivars in the three different geographical regions (Setif, Batna, and Eloued)
Table 6 Pearson's correlation matrix of the leaf morpho-physiological and phytochemical parameters in olive trees
Fig. 4 Principal component analysis performed with all of the measured parameters of olive leaves collected from the Sigoise and Chemlal cultivars in the three different geographical regions (Setif, Batna, and Eloued). PC, principal component; LL, leaf length; LW, leaf width; LSI, leaf shape index; LA, leaf area; FW, fresh weight; DW, dry weight; LTD, leaf tissue density; SLA, specific leaf area; SLW, specific leaf weight; Chl, chlorophyll; Car, carotenoid; TPC, total phenolic content; TFC, total flavonoid content; TTC, total tannin content; IC50, half-maximal inhibitory concentration; Ole, oleuropeoside; HBAs, hydroxybenzoic acids; HCAs, hydroxycinnamic acids; CCAs, cyclohexanecarboxylic acids; Fls, flavones; Fl-ols, flavonols; Flns, flavanones; Fl-3ols, flavan3ols.
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