Bioactive compounds and antioxidant activity of leaves from olive trees grown in Paraná, Brazil

Abstract The objective of this work was to evaluate the bromatological composition, bioactive compounds, antioxidant activities, and color of the leaves of olive cultivars Arbosana, Arbequina, Frantoio, Manzanilla, and Koroneiki in northwestern Paraná, Brazil. Leaves of each cultivar were collected for the experiment, which was carried out in a completely randomized design. The dry matter (DM) of olive leaves contains mostly carbohydrates (56.15 to 59.42 g 100 g-1 DM) and fibers (17.37 to 19.73 g 100 g-1 DM) in its bromatological composition. The total polyphenol content ranges from 13.27 to 22.81 mg GAE g-1, with cultivar Manzanilla standing out, and the flavonoid content from 6.50 to 7.65 mg QE g-1. Manzanilla shows the highest antioxidant activity of 93.56 and 78.15% in the DPPH and ABTS assays, respectively. When compared with the other cultivars, Manzanilla and Koroneiki have leaves with a higher green intensity and total chlorophyll content of 0.958 and 0.833 mg 100 mL 1, respectively. In the ABTS assay, there is a correlation both between total polyphenol content and antioxidant activity and between chlorophyll content and antioxidant activity. Olive leaves have characteristics that allow their application as an additive or ingredient for the development of food products with satisfactory antioxidant activity.

[1]  A. Schieber,et al.  Recent Advances in Research on Polyphenols: Effects on Microbiota, Metabolism and Health. , 2021, Molecular nutrition & food research.

[2]  Pia M. Sörensen,et al.  Olive Leaf Waste Management , 2021, Frontiers in Sustainable Food Systems.

[3]  V. Raghavan,et al.  Optimization of green extraction for the recovery of bioactive compounds from Brazilian olive crops and evaluation of its potential as a natural preservative , 2021 .

[4]  V. Raghavan,et al.  Eco-friendly extraction for the recovery of bioactive compounds from Brazilian olive leaves , 2021, Sustainable Materials and Technologies.

[5]  V. Gupta,et al.  Valorization of fruits and vegetable wastes and by-products to produce natural pigments , 2021, Critical reviews in biotechnology.

[6]  V. Raghavan,et al.  Bio-Based Active Packaging: Carrageenan Film with Olive Leaf Extract for Lamb Meat Preservation , 2020, Foods.

[7]  Jun Wang,et al.  Addition of olive (olea europaea) leaf extract as a source of natural antioxidant in mutton meatball stored at refrigeration temperature , 2020, Journal of Food Science and Technology.

[8]  M. Roca,et al.  Carotenoids and Chlorophylls as Antioxidants , 2020, Antioxidants.

[9]  E. Castro,et al.  Content of phenolic compounds and mannitol in olive leaves extracts from six Spanish cultivars: Extraction with the Soxhlet method and pressurized liquids. , 2020, Food chemistry.

[10]  Abdulkerim Eroglu,et al.  The Colors of Health: Chemistry, Bioactivity, and Market Demand for Colorful Foods and Natural Food Sources of Colorants. , 2020, Annual review of food science and technology.

[11]  D. Rodriguez-Amaya.  Update on natural food pigments - A mini-review on carotenoids, anthocyanins, and betalains. , 2019, Food research international.

[12]  R. Amarowicz,et al.  Genotype-Related Differences in the Phenolic Compound Profile and Antioxidant Activity of Extracts from Olive (Olea europaea L.) Leaves , 2019, Molecules.

[13]  Ying Li,et al.  Factors Influencing Leaf Chlorophyll Content in Natural Forests at the Biome Scale , 2018, Front. Ecol. Evol..

[14]  N. Khalid,et al.  Emerging Technologies for Recovery of Value-Added Components from Olive Leaves and Their Applications in Food/Feed Industries , 2017, Food and Bioprocess Technology.

[15]  M. A. Nunes,et al.  Olive by-products for functional and food applications: Challenging opportunities to face environmental constraints , 2016 .

[16]  Leila Q. Zepka,et al.  Olive leaves offer more than phenolic compounds - Fatty acids and mineral composition of varieties from Southern Brazil , 2015 .

[17]  M. Hammami,et al.  The efficacy of phenolics compounds with different polarities as antioxidants from olive leaves depending on seasonal variations , 2012 .

[18]  Jing Li,et al.  Effect of phosphorus and temperature on chlorophyll a contents and cell sizes of Scenedesmus obliquus and Microcystis aeruginosa , 2011, Limnology.

[19]  T. Beta,et al.  Comparison of antioxidant capacity and phenolic compounds of berries, chokecherry and seabuckthorn , 2009, Central European Journal of Biology.

[20]  C. Rice-Evans,et al.  Antioxidant activity applying an improved ABTS radical cation decolorization assay. , 1999, Free radical biology & medicine.

[21]  M. Nagata,et al.  Simple Method for Simultaneous Determination of Chlorophyll and Carotenoids in Tomato Fruit , 1992 .

[22]  M. Bouaziz,et al.  Structural, antioxidant and antibacterial activities of polysaccharides extracted from olive leaves. , 2018, International journal of biological macromolecules.

[23]  M. Özcan,et al.  A review: benefit and bioactive properties of olive (Olea europaea L.) leaves , 2016, European Food Research and Technology.

[24]  M. O. Moraes,et al.  Composição química e atividade biológica de extrato oleoso de própolis: uma alternativa ao extrato etanólico , 2009 .

[25]  V. L. Singleton,et al.  Colorimetry of Total Phenolics with Phosphomolybdic-Phosphotungstic Acid Reagents , 1965, American Journal of Enology and Viticulture.

[26]  R. Zambiazi,et al.  Evaluation of physicochemical, bioactive composition and profile of fatty acids in leaves of different olive cultivars , 2022 .