Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves
Around two million tons of olive oil are produced in Europe annually, with Portugal being among the top five European olive oil-producing countries. Olive oil production results in a substantial amount of waste in the form of olive leaves. These discarded olive leaves contain valuable phenolic compo...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-01-01
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| Series: | Foods |
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| Online Access: | https://www.mdpi.com/2304-8158/13/2/189 |
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| author | Carolina L. Ronca Sara S. Marques Alberto Ritieni Rafael Giménez-Martínez Luisa Barreiros Marcela A. Segundo |
| author_facet | Carolina L. Ronca Sara S. Marques Alberto Ritieni Rafael Giménez-Martínez Luisa Barreiros Marcela A. Segundo |
| author_sort | Carolina L. Ronca |
| collection | DOAJ |
| description | Around two million tons of olive oil are produced in Europe annually, with Portugal being among the top five European olive oil-producing countries. Olive oil production results in a substantial amount of waste in the form of olive leaves. These discarded olive leaves contain valuable phenolic compounds with antioxidant, anti-inflammatory, hypoglycaemic, neuroprotective, and antiproliferative properties. Due to their richness in polyphenols with health-promoting properties, olive leaves can be considered a potential functional food ingredient. Thus, sustainable practices for reusing olive leaf waste are in demand. In this study, the polyphenolic content in olive leaves from different Portuguese locations was determined using HPLC-UV-Vis after defining the best fit-for-purpose liquid extraction strategy. The differences in the in vitro antioxidant activity in these samples were determined by several methodologies based on radical scavenging (against 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-2-picrylhydrazyl (DPPH), and peroxyl radical (ORAC)) and on reducing properties (cupric-reducing antioxidant capacity (CUPRAC), and Folin–Ciocalteu assay (FC)), to unveil the relationship between the profile and quantity of polyphenols with antioxidant mechanisms and their capacity. At last, the stability of extracted compounds upon lyophilization and exposition to surrogate biological fluids was assessed, envisioning the future incorporation of olive leaves extracted compounds in food products. |
| first_indexed | 2024-03-08T09:54:57Z |
| format | Article |
| id | doaj.art-816c80e820994290924c41cb8aa9bbb6 |
| institution | Directory Open Access Journal |
| issn | 2304-8158 |
| language | English |
| last_indexed | 2024-03-08T09:54:57Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Foods |
| spelling | doaj.art-816c80e820994290924c41cb8aa9bbb62024-01-29T13:51:45ZengMDPI AGFoods2304-81582024-01-0113218910.3390/foods13020189Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive LeavesCarolina L. Ronca0Sara S. Marques1Alberto Ritieni2Rafael Giménez-Martínez3Luisa Barreiros4Marcela A. Segundo5LAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4099-002 Porto, PortugalLAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4099-002 Porto, PortugalDepartment of Pharmacy, Faculty of Pharmacy, University of Naples “Federico II”, 80138 Naples, ItalyDepartment of Nutrition and Bromatology, School of Pharmacy, University of Granada, 18012 Granada, SpainLAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4099-002 Porto, PortugalLAQV, REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, 4099-002 Porto, PortugalAround two million tons of olive oil are produced in Europe annually, with Portugal being among the top five European olive oil-producing countries. Olive oil production results in a substantial amount of waste in the form of olive leaves. These discarded olive leaves contain valuable phenolic compounds with antioxidant, anti-inflammatory, hypoglycaemic, neuroprotective, and antiproliferative properties. Due to their richness in polyphenols with health-promoting properties, olive leaves can be considered a potential functional food ingredient. Thus, sustainable practices for reusing olive leaf waste are in demand. In this study, the polyphenolic content in olive leaves from different Portuguese locations was determined using HPLC-UV-Vis after defining the best fit-for-purpose liquid extraction strategy. The differences in the in vitro antioxidant activity in these samples were determined by several methodologies based on radical scavenging (against 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), 2,2-diphenyl-2-picrylhydrazyl (DPPH), and peroxyl radical (ORAC)) and on reducing properties (cupric-reducing antioxidant capacity (CUPRAC), and Folin–Ciocalteu assay (FC)), to unveil the relationship between the profile and quantity of polyphenols with antioxidant mechanisms and their capacity. At last, the stability of extracted compounds upon lyophilization and exposition to surrogate biological fluids was assessed, envisioning the future incorporation of olive leaves extracted compounds in food products.https://www.mdpi.com/2304-8158/13/2/189circular economyolive oil waste valorizationsustainable extractionfunctional food ingredientsMediterranean dietbioactive compounds |
| spellingShingle | Carolina L. Ronca Sara S. Marques Alberto Ritieni Rafael Giménez-Martínez Luisa Barreiros Marcela A. Segundo Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves Foods circular economy olive oil waste valorization sustainable extraction functional food ingredients Mediterranean diet bioactive compounds |
| title | Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves |
| title_full | Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves |
| title_fullStr | Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves |
| title_full_unstemmed | Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves |
| title_short | Olive Oil Waste as a Source of Functional Food Ingredients: Assessing Polyphenolic Content and Antioxidant Activity in Olive Leaves |
| title_sort | olive oil waste as a source of functional food ingredients assessing polyphenolic content and antioxidant activity in olive leaves |
| topic | circular economy olive oil waste valorization sustainable extraction functional food ingredients Mediterranean diet bioactive compounds |
| url | https://www.mdpi.com/2304-8158/13/2/189 |
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