Olive Leaf: Antimicrobial and Antioxidant Properties, Food Applications, and Current Studies

Year 2023, Volume: 7 Issue: 1, 23 - 43, 30.06.2023

Ayla Mumcu

Abstract

Olive leaves are an important natural source of phenolic compounds with many bioactive properties. It is important to use them in different areas instead of throwing them as waste. Its antioxidant and antimicrobial properties have been proven by many studies and have recently been used in medicine, cosmetics, pharmaceuticals and food products. In this review, the importance of olive leaves, their composition, antimicrobial and antioxidant effects and food applications are briefly explained by giving the recent studies on this subject as examples. This review is likely to be valuable to interested academic and industrial researchers in their studies and knowledge of olive leaves, natural antimicrobials and antioxidants, and innovative food formulations with functional qualities.

Keywords

Food waste, Functional foods, Natural food additives, Olive leaves, Phenolic compounds

References

• Abaza L., Taamalli A., Arráez-Román D., Segura-Carretero A., Fernández-Gutierrérez A., Zarrouk M. & Youssef N.B. 2017. Changes in phenolic composition in olive tree parts according to development stage, Food Research International, 100, 454-461.
• Ahmad-Qasem M.H., Cánovas J., Barrajón-Catalán E., Carreres J.E., Micol V. & García-Pérez J.V. 2014. Influence of olive leaf processing on the bioaccessibility of bioactive polyphenols, Journal of Agricultural and Food Chemistry, 62, 6190-6198..
• Ahmed A.M, Rabii N.S, Gorbaj A.M. & Abolghait S.K. 2014. Antibacterial effect of olive (Olea europaea L.) leaves extract in raw peeled undeveined shrimp (Penaeus semisulcatus), International Journal of Veterinary Science and Medicine, 2, 53-56.
• Akdemir C.S. & Kıymetli Ö. 2021. Antimicrobial activity of olive leaf extract on selected foodborne pathogens and ,ts effect on thermal resistance of Listeria monocytogenes in sous vide ground beef, International Journal of Agriculture Environment and Food Sciences, 5, 236-242.
• Albertos I., Avena-Bustillos R.J., Martín-Diana A.B., Du W.X., Rico D. & McHugh T.H. 2017. Antimicrobial olive leaf gelatin films for enhancing the quality of cold-smoked salmon, Food Packaging and Shelf Life, 13, 49-55.
• Alcántara C., Žugčić T., Abdelkebir R., García-Pérez J.V., Jambrak A.R., Lorenzo J.M., Collado M.C., Granato D. & Barba F.J. 2020. Effects of ultrasound-assisted extraction and solvent on the phenolic profile, bacterial growth, and anti-inflammatory/antioxidant activities of mediterranean olive and fig leaves extracts, Molecules, 25, 1718.
• Al-Rimawi F., Tarawa M.S. & Elama C. 2017. Olive leaf extract as natural antioxidant additive of fresh hamburger stored at 4 ºC running title: antioxidants from olive leaves in hamburger, American Journal of Food Science and Technology, 5, 162-166.
• Aliabadi M.A., Darsanaki R.K., Rokhi M.L., Nourbakhsh M. & Raeisi G. 2012. Antimicrobial activity of olive leaf aqueous extract, Annals of Biological Research, 3, 4189-4191.
• Alirezalu K., Hesari J., Eskandari M.H., Valizadeh H. & Sirousazar M. 2016. Effect of green tea, stinging nettle and olive leaves extracts on the quality and shelf life stability of frankfurter type sausage, Journal of Food Processing and Preservation, 41.
• Aliyari M.A. & Rezaei K. 2021. Improving the biological value of olive and soybean oil blends with olive leaf extract obtained by ultrasound-assisted extraction towards the preparation of a sauce product, Life, 11, 974.
• Ammar S., Kelebek H., Zribi A., Abichou M., Selli S. & Bouaziz M. 2017. LC-DAD/ESI-MS/MS characterization of phenolic constituents in Tunisian extra-virgin olive oils: Effect of olive leaves addition on chemical composition, Food Research International, 100, 477–485.
• Andrikopoulos N.K., Antonopoulou S. & Kaliora A.C. 2002. Oleuropein inhibits LDL oxidation induced by cooking oil frying by-products and platelet aggregation induced by platelet-activating factor, LWT - Food Science and Technology, 35, 479-484.
• Anwar H.M. & Baker I.A. 2022. Effect of ethanolic extract of thyme and olive leave in quality characteristic of lamb patties during storage, Iraqi Journal of Agricultural Sciences, 53, 219-229.
• Aouidi F., Okba A. & Hamdi M. 2017. Valorization of functional properties of extract and powder of olive leaves in raw and cooked minced beef meat, Journal of the Science of Food and Agriculture, 97, 3195-3203.
• Arfaoui M., Boulares M., Bezzezi A., Ayachi S., Ghrab M., Jouini N.E., Hassouna M. & Boudiche S. 2022. Effect of the enrichment with natural antioxidants obtained by maceration or ultrasound-assisted extraction from olive leaves on organic extra virgin olive oil, Rivista Italiana Delle Sostanze Grasse, 99 (2), 121-129.
• Arslan E.E., Karademir G., Berktaş S. & Çam M. 2021. Zeytin yaprağı ekstraktı içeren soğuk çay üretimi, Mühendislik Bilimleri ve Tasarım Dergisi, 9, 843-849.
• Baker I.A. 2015. Investigation on antimicrobial and antioxidant effect of olive leaf extract in Karadi sheep meat during storage, The Iraqi Journal Agricultural Sciences, 46 (6), 1091-1095.
• Balasundram N., Sundram K. & Samman S. 2006. Phenolic compounds in plants and agri-industrial by-products: Antioxidant activity, occurrence, and potential uses, Food Chemistry, 99, 191-203.
• Barbaro B., Toietta G., Maggio R., Arciello M., Tarocchi M., Galli A. & Balsano C. 2014. Effects of the olive-derived polyphenol oleuropein on human health, International Journal of Molecular Sciences, 15, 18508-18524.
• Barukčić I., Filipan K., Lisak Jakopović K., Božanić R., Blažić M. & Repajić M. 2022. The potential of olive leaf extract as a functional ingredient in yoghurtpProduction: The effects on fermentation, rheology, sensory, and antioxidant properties of cow milk yoghurt, Foods, 11 (5), 701.
• Bastante C.C., Cardoso L.C., Fernández-Ponce M.T., Serrano C.M. & De la Ossa E.M. 2019. Supercritical impregnation of olive leaf extract to obtain bioactive films effective in cherry tomato preservation, Food Packaging and Shelf Life, 21, 100338.
• Benavente-Garcia O., Castillo J., Lorente J., Ortuno A. & Del Rio J.A. 2000. Antioxidant activity of phenolics extracted from Olea europaea L. leaves, Food Chemistry, 68, 457–462.
• Bisignano G., Tomaino A., 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, 971-974.
• Blasi F., Urbani E., Simonetti M.S., Chiesi C. & Cossignani L. 2016. Seasonal variations in antioxidant compounds of Olea europaea leaves collected from different Italian cultivars, Journal of Applied Botany and Food Quality, 89, 202-207.
• Borjan D., Leitgeb M., Knez Ž. & Hrnčič M.K. 2020. Microbiological and Antioxidant Activity of Phenolic Compounds in Olive Leaf Extract. Molecules, 25(24),5946. https://doi.org/10.3390/molecules25245946
• Boss A., Bishop K.S., Marlow G., Barnett M.P. & Ferguson L.R. 2016. Evidence to support the anti-cancer effect of olive leaf extract and future directions, Nutrients, 8, 513.
• Bouaziz M., Fki I., Jemai H., Ayadi M., Sayadi S. 2008. Effect of storage on refined and husk olive oils composition: Stabilization by addition of natural antioxidants from Chemlali olive leaves, Food Chemistry, 108, 253-262.
• Cedola A., Palermo C., Centonze D., Del Nobile M.A. & Conte A. 2020. Characterization and bio-accessibility evaluation of olive leaf extract-enriched “Taralli”, Foods, 9, 1268.
• Cetinkaya H., Koc M. & Kulak, M. 2016. Monitoring of mineral and polyphenol content in olive leaves under drought conditions: Application chemometric techniques, Industrial Crops and Products, 88, 78-84.
• Conte P., Pulina S., Del Caro A., Fadda C., Urgeghe P.P., De Bruno A., Difonzo G., Caponio F., Romeo R. & Piga A. 2021. Gluten-Free breadsticks fortified with phenolic-rich extracts from olive leaves and olive mill wastewater, Foods, 10, 923.
• Cueva C., Moreno-Arribas M.V., Martín-Álvarez P.J., Bills G., Vicente M.F., Basilio A., Rivas C.L., Requena T., Rodríguez J.M. & Bartolomé B. 2010. Antimicrobial activity of phenolic acids against commensal, probiotic and pathogenic bacteria, Research in Microbiology, 161, 372–382.
• De la Puerta R., Gutierrez V.R. & Hoult J.R.S. 1999. Inhibition of leukocyte 5-lipoxygenase by phenolics from virgin olive oil, Biochemical Pharmacology, 57, 445-449.
• Dauber C., Carreras T., González L., Gámbaro A., Valdés A., Ibañez E. & Vieitez I. 2022. Characterization and incorporation of extracts from olive leaves obtained through maceration and supercritical extraction in Canola oil: Oxidative stability evaluation, LWT, 160, 113274.
• De Leonardis A, Aretini A, Alfano G, Macciola V. & Ranalli G. 2008. Isolation of a hydroxytyrosol-rich extract from olive leaves (Olea Europaea L.) and evaluation of its antioxidant properties and bioactivity, European Food Research and Technology, 226, 653-659.
• Dekanski D., Ristić S., Radonjić N.V., Petronijević N.D., Dekanski A. & Mitrović D.M. 2011. Olive leaf extract modulates cold restraint stress-induced oxidative changes in rat liver, Journal of the Serbian Chemical Society, 76, 1207-1218.
• Di Meo M.C., Izzo F., Rocco M., Zarrelli A., Mercurio M. & Varricchio E. 2022. Mid-Infrared spectroscopic characterization: New insights on bioactive molecules of Olea europaea L. leaves from selected Italian cultivars, Infrared Physics & Technology, 127, 104439.
• Difonzo G., Pasqualone A., Silletti R., Cosmai L., Summo C., Paradiso V.M. & Caponio F. 2018. Use of olive leaf extract to reduce lipid oxidation of baked snacks, Food Research International, 108, 48-56.
• Djenane D., Gómez D., Yangüela J., Roncalés P. & Ariño A. 2018. Olive leaves extract from algerian oleaster (Olea europaea var. Sylvestris) on microbiological safety and shelf-life stability of raw halal minced beef during display, Foods, 8, 10.
• Dua S., Bhat Z.F. & Kumar S. 2015. Effect of oleuropein on the oxidative stability and storage quality of Tabaq-Maz, fried mutton ribs, Food Bioscience, 12, 84-92.
• Ebeed S., Alaa Eldin M., El-Manakhly E., Al-Rashed S., Hetta H.F., Philippe J., Ramadan Y., Gaber E.L.B. & Eman A. 2020. Effects of olive leaf extracts as natural preservative on retailed poultry meat quality, Foods, 9, 1017.
• EFSA. 2011. Scientific Opinion on the substantiation of health claims related to polyphenols in olive and protection of LDL particles from oxidative damage (ID 1333, 1638, 1639, 1696, 2865), maintenance of normal blood HDL cholesterol concentrations (ID 1639), maintenance of normal blood pressure (ID 3781), “anti-inflammatory properties” (ID 1882), “contributes to the upper respiratory tract health” (ID 3468), “can help to maintain a normal function of gastrointestinal tract” (3779), and “contributes to body defences against external agents” (ID 3467) pursuant to Article 13(1) of Regulation (EC) No 1924/2006, EFSA Journal, 9(4): 2033. https://www.efsa.europa.eu/en/efsajournal/pub/2033.
• EFSA. 2012a. Scientific Report-Compendium of botanicals reported to contain naturally occuring substances of possible concern for human health when used in food and food supplements, EFSA Journal, 10(5):2663. https://www.efsa.europa.eu/en/efsajournal/pub/2663.
• EFSA. 2012b. Scientific Opinion on the substantiation of a health claim related to polyphenols in olive and maintenance of normal blood HDL-cholesterol concentrations (ID 1639, further assessment) pursuant to Article 13(1) of Regulation (EC) No 1924/2006, EFSA Journal, 10(8):2848. https://www.efsa.europa.eu/en/efsajournal/pub/2848.
• EFSA. 2014. Scientific Opinion on the substantiation of a health claim related to olive (Olea europaea L.) leaf water extract and increase in glucose tolerance pursuant to Article 13(5) of Regulation (EC) No 1924/2006. EFSA Journal 12(5): 3655. https://www.efsa.europa.eu/en/efsajournal/pub/3655.
• El S.N. & Karakaya S. 2009. Olive tree (Olea europaea) leaves: potential beneficial effects on human health, Nutrition Reviews, 67, 632-638.
• El-Sohaimy S.A., Mansour H.M., Zeitoun A.A. & Zeitoun M.A.A. 2021. Antioxidant, antimicrobial and anti-inflammatory potential of olive leaves, Zagazig Journal of Agricultural Research, 48, 161-172.
• EMA Monograph. 2017. European Union herbal monograph on Olea Europaea L., folium. European Medicines Agency, Committee on Herbal Medicinal Products, Available online:https://www.ema.europa.eu/en/documents/herbal-report/final-assessment-reportolea-europaea-l-folium-first-version_en.pdf (accessed on 06 January 2023).
• Eraslan Z. 2017. Zeytin yaprağı ekstrakt kullanımının biber salçalarındaki kalite değişimi üzerine etkisi. Yüksek Lisans Tezi, Osmaniye Korkut Ata Üniversitesi Fen Bilimleri Enstitüsü Gıda Mühendisliği Anabilim Dalı, 82 s.
• Famiglietti M., Savastano A., Gaglione R., Arciello A., Naviglio D. & Mariniello L. 2022. Edible films made of dried olive leaf extract and chitosan: Characterization and applications, Foods, 11, 2078.
• Farag R.S., Mahmoud E.A. & Basuny A.M. 2007. Use crude olive leaf juice as a natural antioxidant for the stability of sunflower oil during heating, International Journal of Food Science & Technology, 42, 107-115.
• Ghomari O., Sounni F., Massaoudi Y., Ghanam J., Kaitouni L.B.D., Merzouki M. & Benlemlih M. 2019. Phenolic profile (HPLC-UV) of olive leaves according to extraction procedure and assessment of antibacterial activity, Biotechnology Reports, 23, e00347.
• Giacometti J., Žauhar G. & Žuvić M. 2018. Optimization of ultrasonic-assisted extraction of major phenolic compounds from olive leaves (Olea europaea L.) using response surface methodology, Foods, 7, 149.
• Gök V. & Bor Y. .2012. Effect of olive leaf, blueberry and Zizyphus jujuba extracts on the quality and shelf life of meatball during storage, Journal of Food, Agriculture & Environment, 10, 190-195.
• Gökmen M., Kara R., Akkaya L., Torlak E. & Önen A. 2014. Evaluation of antimicrobial activity in olive (Olea europaea) leaf extract, Am. J. Microbiol., 5, 37-40.
• Gökmen M., Akkaya L., Kara R., Gök V., Önen A. & Ektik N. 2016. Zeytin yaprağı ekstraktı ilavesinin köftelerde S. typhimurium, E. coli O157 ve S. aureus gelişimi üzerine etkisi, Akademik Gıda, 14, 28-32.
• Gyawali R. & Ibrahim S.A. 2014. Natural products as antimicrobial agents, Food Control, 46, 412-429.
• Hashmi M.A., Khan A., Hanif M., Farooq U. & Perveen S. 2015. Traditional Uses, Phytochemistry, and Pharmacology of Olea europaea (Olive), Evidence-Based Complementary and Alternative Medicine, Article ID 541591, http://dx.doi.org/10.1155/2015/541591.
• Hassan M.M.S., Mohdaly A.A.A., Elneairy N.A.A. & Mahmoud A.A. 2022. Using of olive leaves extract for increasing the stability of refined soybean oil, Fayoum Journal of Agricultural Research and Development, 36, 12-20.
• Hayes J.E., Stepanyan V., Allen P., O’Grady M.N. & Kerry J.P. 2010. Effect of lutein, sesamol, ellagic acid and olive leaf extract on the quality and shelf-life stability of packaged raw minced beef patties, Meat Science, 84, 613-620.
• Japon-Lujan R., Luque-Rodriguez J.M. & Luque de Castro M.D. 2006. Dynamic ultrasound-assisted extraction of oleuropein and related biophenols from olive leaves, Journal of Chromatography A, 1108, 76–82.
• Japón-Luján R., Janeiro P. & Luque de Castro M.D. 2008. Solid-liquid transfer of biophenols from olive leaves for the enrichment of edible oils by a dynamic ultrasound-assisted approach, Journal of Agricultural and Food Chemistry, 56, 7231-7235..
• Jiménez P., García P., Bustamante A., Barriga A. & Robert P. 2017. Thermal stability of oils added with avocado (Persea americana cv. Hass) or olive (Olea europaea cv. Arbequina) leaf extracts during the French potatoes frying, Food Chemistry, 221, 123-129.
• Jimenez B., Rivas A., Sánchez-Ortiz A., Lorenzo M.L., Muñoz M.Ú., Callejón R.M. & Quirós E.O.B. 2012. Influence of fruit maturation process on the sensory quality of virgin olive oils from Picual, Hojiblanca and Picudo cultivars, Grasas y Aceites, 63, 403-410.
• Jung Y.C., Kim H.W., Min B.K., Cho J.Y., Son H. J, Lee J.A.Y., Kim J., Kwon S., Li Q. & Lee H.W. 2019. Inhibitory effect of olive leaf extract on obesity in high-fat diet-induced mice, In Vivo, 33, 707-715.
• Keskin D., Ceyhan N., Uğur A. & Dbeys A.D. 2012. Antimicrobial activity and chemical constitutions of West Anatolian olive (Olea europaea L.) leaves, Journal of Food, Agriculture & Environment, 10, 99-102.
• Khalifa I., Barakat H., El-Mansy H.A. & Soliman S.A. 2016. Improving the shelf-life stability of apple and strawberry fruits applying chitosan-incorporated olive oil processing residues coating, Food Packaging and Shelf Life, 9, 10–19.
• Khemakhem I., Ahmad-Qasem M.H., Catalán E.B., Micol V., García-Pérez J.V. & Ayadi M.A. 2017. Kinetic improvement of olive leaves’ bioactive compounds extraction by using power ultrasound in a wide temperature range, Ultrason Sonochem., 34, 466–73.
• Kiritsakis K., Rodríguez‐Pérez C., Gerasopoulos D. & Segura‐Carretero A. 2017. Olive oil enrichment in phenolic compounds during malaxation in the presence of olive leaves or olive mill wastewater extracts, European Journal of Lipid Science and Technology, 119, 1600425.
• Kurt Ş. & Ceylan H.G. 2017. Effects of olive leaf extract on the oxidation stability and microbiological quality of dry fermented sausage (Sucuk), Carpathian Journal of Food Science & Technology, 9 (4).
• Lahreche T., Durmuş M., Tumerkan E.T.A., Hamdi T.M. & Özoğul F. 2020. Olive leaf extracts application for shelf life extension of vacuum-packed frigate mackerel (Auxis thazard) fillets, Carpathian Journal of Food Science and Technology, 12.
• Lee O. & Lee B. 2010. Antioxidant and antimicrobial activities of individual and combined phenolics in Olea europea leaf extract, Bioresource Technology, 101, 3751-3754.
• Lee-Huang S., Zhang L., Huang P.L., Chang Y.T. & Huang P.L. 2003. Anti-HIV activity of olive leaf extract (OLE) and modulation of host cell gene expression by HIV-1 infection and OLE treatment, Biochemical and Biophysical Research Communications, 307, 1029-1037.
• Liu Y., McKeever L.C. & Malik N.S.A. 2017. Assessment of the antimicrobial activity of olive leaf extract against foodborne bacterial pathogens, Frontiers in Microbiology, 8.
• Lockyer S., Rowland I., Spencer J.P.E., Yaqoob P. & Stonehouse W. 2017. Impact of phenolic-rich olive leaf extract on blood pressure, plasma lipids and inflammatory markers: A randomised controlled trial, European Journal of Nutrition, 56, 1421-1432.
• Malheiro R., Casal S., Teixeira H., Bento A. & Pereira J.A. 2013. Effect of olive leaves addition during the extraction process of overmature fruits on olive oil quality, Food and Bioprocess Technology, 6, 509-521.
• Malik N.S.A. & Bradford J.M. 2008. Recovery and stability of oleuropein and other phenolic compounds during extraction and processing of olive (Olea europaea L.) leaves, Journal of Food, Agriculture & Environment, 6, 8-13.
• Marhamatizadeh M.H., Ehsandoost E., Gholami P. & Mohaghegh M.D. 2013. Effect of olive leaf extract on growth and viability of Lactobacillus acidophilus and Bifidobacterium bifidum for production of probiotic milk and yoghurt, International Journal of Farming and Allied Sciences, 2 (17), 572-578.
• Markin D., Duek L. & Berdicevsky I. 2003. In vitro antimicrobial activity of olive leaves, Mycoses, 46, 132–136.
• Moudache M., Nerín C., Colon M. & Zaidi F. 2017. Antioxidant effect of an innovative active plastic film containing olive leaves extract on fresh pork meat and its evaluation by Raman spectroscopy, Food Chemistry, 229, 98-103.
• Musella E., Ouazzani I.C.E., Mendes A.R., Rovera C., Farris S., Mena C., Teixeira P. & Poças F. 2021. Preparation and characterization of bioactive chitosan-based films incorporated with olive leaves extract for food packaging applications, Coatings, 11, 1339.
• Mutlu A. & Bilgin Ş. 2016. The effects of olive (Olea europaea L.) leaf and oil-bearing rose (Rosa damascena Mill.) extracts on shelf life of hot smoked rainbow trout (Oncorhynchus mykiss) fillets during refrigerated storage (4±1° C), Journal of Limnology and Freshwater Fisheries Research, 2, 19-29.
• Nasrollahi Z. & Abolhasannezhad M. 2015. Evaluation of the antifungal activity of olive leaf aqueous extracts against Candida albicans PTCC-5027, Current Medical Mycology, 1, 37-39.
• Oniszczuk A., Widelska G., Wójtowicz A., Oniszczuk T., Wojtunik-Kulesza K., Dib A. & Matwijczuk A. 2019. Content of phenolic compounds and antioxidant activity of new gluten-free pasta with the addition of chestnut flour, Molecules, 24, 1-14.
• Özcan M.M. & Matthäus B. 2017. A review: benefit and bioactive properties of olive (Olea europaea L.) leaves, European Food Research and Technology, 243, 89-99.
• Palmeri R., Monteleone J., Barbera A., Maucieri C., Todaro A., Giannone V. & Spagna G. 2016. Production of functional crackers enriched with olive (Olea europaea L.) leaf extract, In ICFPTS 2016: 18th International Conference on Food Processing Technology and Supplements. GB.
• Palmeri R., Parafati L., Trippa D., Siracusa L., Arena E., Restuccia C. & Fallico B. 2019. Addition of olive leaf extract (OLE) for producing fortified fresh pasteurized milk with an extended shelf life, Antioxidants, 8, 255.
• Peker H. & Arslan S. 2017. Effect of olive leaf extract on the quality of low fat apricot yogurt, Journal of Food Processing and Preservation, 41, e13107.
• Pereira A.P., Ferreira I.C., Marcelino F., Valentão P., Andrade P.B., Seabra R., Estevinho L., Bento A. & Pereira J.A. 2007. A Phenolic compounds and antimicrobial activity of olive (Olea europaea L. cv. Cobrançosa) leaves, Molecules, 12, 1153-1162.
• Pourghorban S., Yadegarian L., Jalili M. & Rashidi L. 2022. Comparative Physicochemical, Microbiological, Antioxidant, and Sensory properties of pre‐and post‐fermented yoghurt enriched with olive leaf and its extract, Food Science & Nutrition, 10, 751-762.
• Qabaha K., Al-Rimawi F., Qasem A. & Naser S.A. 2018. Oleuropein is responsible for the major anti-inflammatory effects of olive leaf extract, Journal of Medicinal Food, 21, 302-305.
• Quiñones M., Miguel M. & Aleixandre A. 2012. Los polifenoles, compuestos de origen natural con efectos saludables sobre el sistema cardiovascular, Nutrición Hospitalaria, 27, 76–89.
• Rachman A.B., Akazawa T. & Ogawa M. 2021. Olive leaf water extract protects chicken breast sausages against quality deterioration induced by frozen storage, The Journal of Poultry Science, 58, 200-209.
• Rahmanian N., Jafari S.M. & Wani T.A. 2015. Bioactive profile, dehydration, extraction and application of the bioactive components of olive leaves, Trends in Food Science & Technology, 42, 150–172.
• Rietjens S.J., Bast A., Vente J. & Haenen G.R.M.M. 2007. The olive oil antioxidant hydroxytyrosol efficiently protects agains the oxiative stress-inuced impairment of the NO response of isolated rat aorta, Am J Physiol Heart Circ Physiol, 292:H1931-H1936.
• Robards K., Prenzler P.D., Tucker G., Swatsitang P. & Glover W. 1999. Phenolic compounds and their role in oxidative processes in fruits, Food Chemistry, 66, 401–436.
• Romeo R., De Bruno A., Piscopo A., Brenes M. & Poiana M. 2021. Effects of phenolic enrichment on antioxidant activity of mayonnaise, Chemical Engineering Transactions, 87, 127-132.
• 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 L, Nutrients, 11, 1776.
• Saija A. & Uccella N. 2000. Olive biophenols: functional effects on human wellbeing, Trends in Food Science & Technology, 11, 357-363.
• Salta F.N., Mylona A., Chiou A., Boskou G. & Andrikopoulos N.K. 2007. Oxidative stability of edible vegetable oils enriched in polyphenols with olive leaf extract, Food Science and Technology International, 13, 413-421.
• Sanchez J.C., Alsina M.A., Herrlein M.K. & Mestres C. 2007. Interaction between the antibacterial compound, oleuropein, and model membranes, Colloid and Polymer Science, 285, 1351–1360.
• Sánchez-Gutiérrez M., Bascón-Villegas I., Rodríguez A., Pérez-Rodríguez F., Fernández-Prior Á., Rosal A. & Carrasco E. 2021. Valorisation of Olea europaea L. olive leaves through the evaluation of their extracts: Antioxidant and antimicrobial activity, Foods, 10, 966.
• Sevim D., Tuncay O. & Koseoglu O. 2013. The effect of olive leaf addition on antioxidant content and antioxidant activity of “Memecik” olive oils at two maturity stages, Journal of American Oil Chemists’ Society, 90, 1359–1369.
• Shialy Z., Zarrin M., Nejad B.S. & Naanaie S.Y. 2015. In vitro antifungal properties of Pistacia atlantica and olive extracts on different fungal species, Current Medical Mycology, 1, 40-45.
• Souilem S., Fki I., Kobayashi I., Khalid N., Neves M.A., Isoda H., Sayadi S. & Nakajima M. 2017. Emerging technologies for recovery of value-added components from olive leaves and their applications in food/feed industries, Food and Bioprocess Technology, 10, 229-248.
• Stojković D., Petrović J., Soković M., Glamočlija J., Kukić-Marković J. & Petrović S. 2013 In situ antioxidant and antimicrobial activities of naturally occurring caffeic acid, p-coumaric acid and rutin, using food systemS, Journal of the Science of Food and Agriculture, 93, 3205–3208.
• Sudjana A.N., D’Orazio C., Ryan V., Rasool N., Ng J., Islam N., Riley T.V. & Hammer K.A. 2009. Antimicrobial activity of commercial Olea europaea (olive) leaf extract, International Journal of Antimicrobial Agents, 33, 461-463.
• Taamalli A., Arráez-Román D., Barrajón-Catalán E., Ruiz-Torres V., Pérez-Sánchez A., Herrero M., Ibañez E., Micol V., Zarrouk M., Segura-Carretero A. & Fernández-Gutiérrez A. 2012. Use of advanced techniques for the extraction of phenolic compounds from tunisian olive leaves: phenolic composition and cytotoxicity against human breast cancer cells, Food and Chemical Toxicology, 50, 1817–1825.
• Talhaoui N., Taamalli A., Gómez-Caravaca A.M., Fernández-Gutiérrez A. & Segura-Carretero A. 2015. Phenolic compounds in olive leaves: Analytical determination, biotic and abiotic influence, and health benefits, Food Research International, 77, 92-108.
• Tarchoune I., Sgherri C., Eddouzi J., Zinnai A., Quartacci M.F. & Zarrouk M. 2019. Olive leaf addition increases olive oil nutraceutical properties, Molecules, 24, 545.
• Techathuvanan C., Reyes F., David J.R. & Davidson P.M. 2014. Efficacy of commercial natural antimicrobials alone and in combinations against pathogenic and spoilage microorganisms, Journal of Food Protection, 77, 269–275.
• THIE. 2019. Allocation List of Herbals Considered as Food (Former EHIA Document). https://thie-online.eu/files/thie/docs/2019-09-26_PU_THIE_Inventory_List_status_27- 06-2019_final.pdf. Visioli F. & Galli C. 2002. Biological properties of olive oil phytochemicals, Critical Reviews in Food Science Nutrition, 42, 209–221.
• Visioli F., Poli A. & Galli C. 2002. Antioxidant and other biological activities of phenols from olives and olive oil, Medicinal Research Reviews, 22, 65–75..
• Vizza D., Lupinacci S., Toteda G., Puoci F., Ortensia P., De Bartolo A., Lofaro D., Scrivano L., Bonofiglio R., La Russa A., Bonofiglio M. & Perri A. 2019. An olive leaf extract rich in polyphenols promotes apoptosis in cervical cancer cells by upregulating p21cip/waf1 gene expression, Nutrition and Cancer, 71, 320-333.
• Wainstein J., Ganz T., Boaz M., Dayan Y.B., Dolev E., Kerem Z. & Madar Z. 2012. Olive leaf extract as a hypoglycemic agent in both human diabetic subjects and in rats, Journal of Medicinal Food, 15, 605-610.
• Xiang Z. & Ning Z. 2008. Scavenging and antioxidant properties of compound derived from chlorogenic acid in South-China honeysuckle, LWT-Food Science and Technology, 41, 1189-1203. Xie P., Huang L., Zhang C. & Zhang Y. 2015. Phenolic compositions, and antioxidant performance of olive leaf and fruit (Olea europaea L.) extracts and their structure-activity relationship, J. Funct. Foods, 16, 460–471.
• Zoidou E., Magiatis P., Melliou E., Constantinou M., Haroutounian S. & Skaltsounis A.L. 2014. Oleuropein as a bioactive constituent added in milk and yogurt, Food Chemistry, 158, 319-324.
• Zorić N., Kopjar N., Bobnjarić I., Horvat I., Tomić S. & Kosalec I. 2016a. Antifungal activity of oleuropein against Candida albicans-The in vitro study, Molecules, 21, 1631,
• Zorić N., Kopjar N., Kraljić K., Orśolić N., Tomić S. & Kosalec I. 2016b. Olive leaf extract activity against Candida albicans and C. dubliniensis - the in vitro viability study, Acta Pharmaceutica, 66, 411 - 421.
• Zribi A., Gargouri B., Jabeur H., Rebaï A., Abdelhedi R. & Bouaziz M. 2013. Enrichment of pan‐frying refined oils with olive leaf phenolic‐rich extract to extend the usage life, European Journal of Lipid Science and Technology, 115, 1443-1453.