Document Type : Full Research Paper

Authors

1 Department of Food Science and Technology, Faculty of Animal Science and Food Technology, Agricultural Sciences and Natural Resources University of Khuzestan, Mollasani, Iran

2 Department of Food Science and Technology, Faculty of Animal Science and Food Technology, Agricultural Sciences and Natural Resources University of Khuzestan, Mollasani, Iran.

3 Department of Horticultural Science, Faculty of Agriculture, Agricultural Sciences and Natural Resources University of Khuzestan, Mollasani, Iran.

Abstract

[1]Introduction: Oxidation and food pathogens are considered two important and influential factors affecting food quality and health. Recently, due to the increasing demand for natural products, the application of synthetic preservatives to control microbial growth and lipid oxidation have been decreased significantly. Therefore, natural antioxidant and antimicrobial compounds are receiving more attention in food preservation technologies. In the last 2 decades, the use of herbal medicines rich in bioactive molecules (including polyphenols, carotenoids and flavonoids) with medicinal and health effects such as delaying the onset of some diseases such as cardiovascular disorders, diabetes, and cancer have increased. Furthermore, secondary metabolites in plant extracts and essential oils are able to control and inhibit free radical-mediated reactions. The olive tree (Olea europaea) is an evergreen plant that grows in tropical and subtropical regions. Iran is one of the most important olive growers in the world due to its suitable conditions for olive cultivation. The leaves of the olive plant have a high potential for the production of various products such as tea and extracts. Olive leaf extract can be used as a raw material in the production of various products, due to exhibiting various biological activities such as antimicrobial and antiviral activity, lipid stabilizer, blood pressure regulator, antioxidant activity, and free radical scavenger. The leaves of the olive tree also contain various phenolic compounds, mainly Oleuropein and hydroxytyrosol, with antioxidant and antimicrobial activities. Therefore, in this study, the amount of phenolic and flavonoid compounds of olive leaf ethanolic extract and its antioxidant effect and antimicrobial properties on Escherichia coli, Enterobacter aerogenesis, Bacillus cereus and Listeria innocua were investigated.
 
Materials and Methods: The olive leaf ethanolic extract was prepared through maceration method and its total phenolic content (Folin-Ciocalteu method), total flavonoids content (aluminum chloride colorimetric assay), antioxidant activity (ABTS and DPPH free radical scavenging methods), and antimicrobial effect on E. coli, E. aerogenesis, B. cereus and L. innocua (based on disk diffusion agar, well diffusion agar, minimum inhibitory concentration, and minimum bactericidal concentration) were determined according to standard methods. Data were analyzed by SPSS software through one-way ANOVA and Duncan test at p<0.05. 
 
Results and Discussion: The ethanolic extract of olive leaves contained 176.58 ± 0.72 mg GAE/g total phenol and 69.85 ± 0.26 mg QE/g total flavonoids. In addition, ethanolic extract of olive leaf was able to inhibit free radicals DPPH (70.62 ± 0.59%) and ABTS (76.15 ± 0.43%). The antimicrobial results showed that the antimicrobial effect of the extract depended on its concentration and type of bacteria. Antimicrobial effect was increased as a function of ethanolic extract, and Gram-positive bacteria (B. cereus and L. innocua) were more sensitive to ethanolic extract of olive leaf than Gram-negative bacteria (E. aerogenesis and E. coli). Generally, B. cereus and E. aerogenesis were the most sensitive and resistant microbial strains to ethanolic extract of olive leaf, respectively.
The results of this study showed that the high antioxidant and antimicrobial activity of olive leaf ethanolic extract is mainly due to its phenolic and flavonoid compounds. Olive leaf ethanolic extract was able to neutralize DPPH and ABTS free radicals. Also, Gram-positive bacteria were more sensitive to ethanolic extract of olive leaf than Gram-negative bacteria. In general, the ethanolic extract of olive leaf can be used as a nutraceutical to control or prevent the growth of spoilage/infection-causing microorganisms and free radical reactions in food and the human body. However, more in-depth studies are needed to determine the mechanism of antimicrobial and antioxidant effects of olive ethanolic extract in vitro and in vivo.

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    1. Abbas Vali, M., Esmaili Kutmehr, M., Mushtaghi, H., & Eskandari, M. (2015). Comparison of the antibacterial effect of the leaf extracts of four varieties of olive (Olea europaea) on Bacillus cereus. Food Hygiene, 5(2), 41-52.
    2. Abbas Vali, M., Esmaili Kutmehr, M., Mushtaghi, H., & Eskandari, M. (2015). Investigating the antibacterial effect of acetone, ethanol and methanol extracts of four Iranian olive varieties on Escherichia coli. Food Microbiology, 2(2), 67-77.
    3. Aghajani, Z., & Khabarizadeh, M. (2015). The antioxidant activity of two varieties of olive leaves (Mission and Conservalia). Scientific Research Applied Biology, 5(18), 1-8.
    4. Alizadeh Behbahani, B., & Shahidi, F. (2019). Melissa officinalis essential oil: Chemical compositions, antioxidant potential, total phenolic content and antimicrobial activity. Nutrition and Food Sciences Research, 6(1), 17-25.
    5. Alizadeh Behbahani, B., Falah, F., Lavi Arab, F., Vasiee, M., & Tabatabaee Yazdi, F. (2020). Chemical composition and antioxidant, antimicrobial, and antiproliferative activities of Cinnamomum zeylanicum bark essential oil. Evidence-based complementary and alternative medicine, 2020.
    6. Alizadeh Behbahani, B., Falah, F., Vasiee, A., & Tabatabaee Yazdi, F. (2021). Control of microbial growth and lipid oxidation in beef using a Lepidium perfoliatum seed mucilage edible coating incorporated with chicory essential oil. Food Science & Nutrition, 9(5), 2458-2467. https://doi.org/10.1002/fsn3.2186
    7. Alizadeh Behbahani, B., Fallah, F., Ehaghi, A., Tabatabai Yazdi, F., & Mortazavi, S. (2019). Antimicrobial effect of Citrus aurantium essential oil on some food borne pathogens and determination of its chemical compounds, total phenolcontent, total flavonoids content and antioxidant potential. Journal of food science and technology (Iran), 16(87), 291-304.
    8. Alizadeh Behbahani, B., Noshad, M. and Fallah, F. (2019). Study of chemical structure, antimicrobial, cytotoxic and mechanism of action of syzygium aromaticum essential oil on foodborne pathogens. Potravinarstvo Slovak Journal of Food Sciences, 13(1), 875-883.
    9. Alizadeh Behbahani, B., Noshad, M., & Falah, F. (2019). Cumin essential oil: Phytochemical analysis, antimicrobial activity and investigation of its mechanism of action through scanning electron microscopy. Microbial pathogenesis, 136, 103716. https://doi.org/10.1016/j.micpath.2019.103716
    10. Alizadeh Behbahani, B., Shahidi, F., Yazdi, F. T., Mortazavi, S. A., & Mohebbi, M. (2017). Antioxidant activity and antimicrobial effect of tarragon (Artemisia dracunculus) extract and chemical composition of its essential oil. Journal of Food Measurement and Characterization, 11(2), 847-863. https://doi.org/10.1007/s11694-016-9456-3
    11. Alizadeh Behbahani, B., Tabatabaei Yazdi, F., Mortazavi, A., Zendeboodi, F., Gholian, M. M., & Vasiee, A. (2013). Effect of aqueous and ethanolic extract of Eucalyptus camaldulensis on food infection and intoxication microorganisms “in vitro”. Archives of Advances in Biosciences, 4(3), 89-99.
    12. Alizadeh Behbahani, B., Yazdi, F. T., Shahidi, F., Noorbakhsh, H., Vasiee, A., & Alghooneh, A. (2018). Phytochemical analysis and antibacterial activities extracts of mangrove leaf against the growth of some pathogenic bacteria. Microbial pathogenesis, 114, 225-232. https://doi.org/10.1016/j.micpath.2017.12.004
    13. Barzegar, H., Behbahani, B. A., & Mehrnia, M. A. (2020). Quality retention and shelf life extension of fresh beef using Lepidium sativum seed mucilage-based edible coating containing Heracleum lasiopetalum essential oil: an experimental and modeling study. Food Science and Biotechnology, 29(5), 717-728. https://doi.org/10.1007/s10068-019-00715-4
    14. Barzegar, H., Mehrnia, M. A., & Alizadeh Behbahani, B. (2017). Determination of the chemical composition, antioxidant activity and the antimicrobial effect of Heracleum Lasiopetalum on infection and food poisoning microorganisms. Journal of Applied microbiology in food industries, 16(90), 113-125.
    15. Benavente-Garcıa, O., Castillo, J., Lorente, J., Ortuño, A., & Del Rio, J. (2000). Antioxidant activity of phenolics extracted from Olea europaea L. leaves. Food Chemistry, 68(4), 457-462. https://doi.org/10.1016/S0308-8146(99)00221-6
    16. Bisignano, G., Tomaino, , Cascio, R. L., Crisafi, G., Uccella, N., & Saija, A. (1999). On the in-vitro antimicrobial activity of oleuropein and hydroxytyrosol. Journal of pharmacy and pharmacology, 51(8), 971-974. https://doi.org/10.1211/0022357991773258
    17. Del Rı́o, J., Báidez, A., Botı́a, J., & Ortuno, A. (2003). Enhancement of phenolic compounds in olive plants (Olea europaea L.) and their influence on resistance against Phytophthora sp. Food Chemistry, 83(1), 75-78. https://doi.org/10.1016/S0308-8146(03)00051-7
    18. Falah, F., Shirani, K., Vasiee, A., Yazdi, F. T., & Behbahani, B. A. (2021). In vitro screening of phytochemicals, antioxidant, antimicrobial, and cytotoxic activity of Echinops setifer extract. Biocatalysis and Agricultural Biotechnology, 35, 102102. https://doi.org/10.1016/j.bcab.2021.102102
    19. Hayes, J., Allen, P., Brunton, N., O’grady, M., & Kerry, J. (2011). Phenolic composition and in vitro antioxidant capacity of four commercial phytochemical products: Olive leaf extract (Olea europaea), lutein, sesamol and ellagic acid. Food Chemistry, 126(3), 948-955. https://doi.org/10.1016/j.foodchem.2010.11.092
    20. Jafarian, P., Asefi, N., & Teimori, R. (2014). Phenolic compounds content in leaf of different varieties of olive and its effect on stability of rapeseed oil, Journal of food research. 24(3), 307-314.
    21. Karametjo, A., Hissari, J., Azadmard Demirchi, S., Prophet Doost, S., & Nemati, M. (2013). Antioxidant effect of olive leaf extract on butter stability. Journal of Food Processing and Preservation, 5(1), 81-94.
    22. Keramatjou., E., Hesari, J., Azadmard-Damirchi., S., & Peighambardoust., S.H. (2013). Antioxidant effect of olive leaf on stability of butter. Journal of Food Processing and Preservation, 5(1), 81-94.
    23. Kiarsi, Z., Hojjati, M., Behbahani, B. A., & Noshad, M. (2020). In vitro antimicrobial effects of Myristica fragrans essential oil on foodborne pathogens and its influence on beef quality during refrigerated storage. Journal of Food Safety, 40(3), e12782. https://doi.org/10.1111/jfs.12782
    24. Kiritsakis, K., Kontominas, M., Kontogiorgis, C., Hadjipavlou‐Litina, D., Moustakas, , & Kiritsakis, A. (2010). Composition and antioxidant activity of olive leaf extracts from Greek olive cultivars. Journal of the American Oil Chemists' Society, 87(4), 369-376. https://doi.org/10.1007/s11746-009-1517-x
    25. Lee, O.-H., & Lee, B.-Y. (2010). Antioxidant and antimicrobial activities of individual and combined phenolics in Olea europaea leaf extract. Bioresource technology, 101(10), 3751-375. https://doi.org/10.1016/j.biortech.2009.12.052
    26. Lins, P. G., Pugine, S. M. P., Scatolini, A. M., & de Melo, M. P. (2018). In vitro antioxidant activity of olive leaf extract (Olea europaea ) and its protective effect on oxidative damage in human erythrocytes. Heliyon, 4(9), e00805. https://doi.org/10.1016/j.heliyon.2018.e00805
    27. Majeed, M., & Prakash, L. (2006). Natural antimicrobials and preservatives: An emerging trend in personal care. Soap Perfumery and Cosmetics, 1, 87-92.
    28. Mallakian, S., Elhami Rad, A., Beyg Babaei, A., & Mohammadi, M. (2019). Antibacterial properties of olive leaf extracts extracted by subcritical water method on food borne pathogen. Journal of Applied microbiology in food industries, 5(2), 27-38.
    29. Najafian, L., Haddad Khodaparast, M., & Alireza Qods Vali, A. (2007). Olive oil extraction from three olive varieties using enzyme processing. Journal of food science and technology (Iran), 4(12), 45-53.
    30. Noktehsanj Avval, M., Jahed, A., Mahdian, R., & Azari Anpar, M. (2018). Evaluation of the effect of olive leaf extract as a beneficial compound on the physicochemical, microbial and sensory characteristics of pulped tomato juice drink. Journal of Innovation in Food Science and Technology, 10(4), 119-136.
    31. Noshad, M., Hojjati, M., & Behbahani, B. A. (2018). Black Zira essential oil: Chemical compositions and antimicrobial activity against the growth of some pathogenic strain causing infection. Microbial pathogenesis, 116, 153-157. https://doi.org/10.1016/j.micpath.2018.01.026
    32. Pereira, A. P., Ferreira, I. C., Marcelino, F., Valentão, P., Andrade, P. B., Seabra, R., . . . Pereira, J. A. (2007). Phenolic compounds and antimicrobial activity of olive (Olea europaea Cv. Cobrançosa) leaves. Molecules, 12(5), 1153-1162. https://doi.org/10.3390/12051153
    33. Rafiee, Z., Jafari, S. M., Khomeiri, M., & Alami, M. (2011). Effect of variety and method of extraction on antioxidant and antimicrobial activity of olive leaf extracts. Iranian Food Science & Technology Research Journal, 6(4), 297-308.
    34. Romani, A., Ieri, F., Urciuoli, S., Noce, A., Marrone, G., Nediani, C., & Bernini, R. (2019). Health effects of phenolic compounds found in extra-virgin olive oil, by-products, and leaf of Olea europaea Nutrients, 11(8), 1776. https://doi.org/10.3390/nu11081776
    35. Silva, S., Gomes, L., Leitao, F., Coelho, A., & Boas, L. V. (2006). Phenolic compounds and antioxidant activity of Olea europaea fruits and leaves. Food Science and Technology International, 12(5), 385-395. https://doi.org/10.1177/108201320607016
    36. Sosani Gharibvand, Z., Alizadeh Behbahani, B., Noshad, M., & Jooyandeh, H. (2020). Investigation of the functional groups of bioactive compounds, radical scavenging potential, antimicrobial activity and cytotoxic effect of Callistemon Citrinus aqueous extract on cell line ht29: a laboratory study. Journal of Rafsanjan University of Medical Sciences, 19(5), 463-484.
    37. Tabatabaei Yazdi, F., & Alizadeh Behbahani, B. (2013). Antimicrobial effect of the aqueous and ethanolic Teucrium polium extracts on Gram positive and Gram negative bacteria “in vitro”. Archives of Advances in Biosciences, 4(4), 56-62.
    38. Tabatabaei Yazdi, F., Alizadeh Behbahani, B., Vasiee, A. R., Mortazavi, S. A., & Shahidi, F. (2018). Evaluation antioxidant activity, phytochemical constituents and antimicrobial of Mentha Piperita essential oil on some infectious and poisonous microorganisms. Journal of food science and technology (Iran), 15(76), 67-76.
    39. Tabatabai Yazdi, F., Ali Zadeh Behbahani, B., Alghoneh, A., & Zanganeh, H. (2016). Optimization of extraction of Mespilus germanica by mixture design and investigation of its effect on Infectious Microorganisms “in vitro”. Journal of food science and technology (Iran), 13(52), 131-145.
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