scholarly journals Microbiological and Antioxidant Activity of Phenolic Compounds in Olive Leaf Extract

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5946
Author(s):  
Dragana Borjan ◽  
Maja Leitgeb ◽  
Željko Knez ◽  
Maša Knez Hrnčič
Keyword(s):  
Phenolic Compounds ◽  
Leaf Extract ◽  
Biological Activities ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Olive Leaf Extract ◽  
Antimicrobial Potential ◽  
Isolation And Characterization ◽  
Wide Range

According to many reports, phenolic compounds isolated from olive leaves have very good biological activities, especially antimicrobial. Presently, the resistance of microorganisms to antibiotics is greater than ever. Therefore, there are numerous recent papers about alternative solutions for inhibiting their influence on human health. Olive leaf is studied as an important source of antimicrobials with low cost and used in medicine. Numerous publications on involving green technologies for isolation of active compounds from olive leaves have appeared over the past few decades. The present review reports on current knowledge of the most isolated phenolic compounds from olive leaf extract as well as methods for their isolation and characterization. This paper uses recent research findings with a wide range of study models to describe the antimicrobial potential of phenolic compounds. It also describes the vast range of information about methods for determination of antimicrobial potential focusing on effects on different microbes. Additionally, it serves to highlight the role of olive leaf extract as an antioxidants and presents methods for determination of antioxidant potential. Furthermore, it provides an overview of presence of enzymes. The significance of olive leaves as industrial and agricultural waste is emphasized by means of explaining their availability, therapeutic and nutritional effects, and research conducted on this field.

Oxidative Stability of Edible Vegetable Oils Enriched in Polyphenols with Olive Leaf Extract

2007 ◽  
Vol 13 (6) ◽  
pp. 413-421 ◽  
Author(s):  
F.N. Salta ◽  
A. Mylona ◽  
A. Chiou ◽  
G. Boskou ◽  
N.K. Andrikopoulos
Keyword(s):  
Phenolic Compounds ◽  
Oxidative Stability ◽  
Antioxidant Capacity ◽  
Hplc Analysis ◽  
Leaf Extract ◽  
Olive Leaf ◽  
Total Polyphenols ◽  
Olive Leaf Extract ◽  
Rancimat Method ◽  
Oil Sunflower

Commercially available oils (olive oil, sunflower oil, palm oil, and a vegetable shortening) were enriched in polyphenols, by adding olive leaf extract. Addition of the extract was performed in such way that the oils were enriched with 200 mg/kg polyphenols. Total polyphenols of both enriched and commercial oils were estimated by the Folin—Ciocalteau assay, while identification and quantification of individual simple phenolic compounds was performed by GC/MS and of oleuropein by HPLC analysis. The enrichment resulted in the supplementation of the commercial oils mainly with oleuropein, hydroxytyrosol, and quercetin. Antioxidant capacity and oxidative stability of the enriched oils and the commercial ones were assessed by the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•) scavenging assay and the Rancimat method, respectively. Both antioxidant capacity and oxidative stability were substantially improved for all the oils studied after supplementation. By the procedure adopted, oils rich in polyphenols, mainly in oleuropein, can be produced with olive leaf extract supplementation.

scholarly journals Zeytin Yaprağı Ekstraktı ve Oleuropeinin Antioksidan, Antimikrobiyal Aktivitesi, Gıdalarda Kullanım Olanakları

2020 ◽  
Vol 8 (2) ◽  
pp. 337
Author(s):  
Mustafa Bayram ◽  
Semra Topuz ◽  
Cemal Kaya
Keyword(s):  
Phenolic Compound ◽  
Leaf Extract ◽  
Folk Medicine ◽  
Value Added ◽  
Olive Tree ◽  
Antimicrobial Activities ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Food Preservatives ◽  
Olive Leaf Extract

Olive leaves which is one of the by-products of olive tree cultivation and olive processing industry, have been used in traditional folk medicine for centuries. In recent studies, it has been determined that olive leaf has many bioactivities and these effects have been associated with high phenolic compound content. The most dominant phenolic compound of olive leaf is oleuropein, which is the heterosidic ester of elenolic acid and 3,4-dihydroxyphenylethanol. Therefore, some studies have been carried out for extracting high value added compounds from olive leaves in recent years. Antioxidant and antimicrobial activities of crude phenolic extract and oleuropein have been investigated. Moreover, some studies have been carried out to increase the possibility of using olive leaf extract and oleuropein in food industry due to increasing suspicion of side effects and toxicity of synthetic food preservatives. In this review, it was aimed to investigate phenolic compounds of olive leaf extract, phenolic compound extraction from olive leaf as well as antioxidant, antimicrobial activity of olive leaf extract and oleuropein and possibilities of use in foods.

scholarly journals Effect of Nitrite Substitution with Olive Leaves Extract on Color and Sensory Properties of Beef Mortadella

2015 ◽  
Vol 7 (12) ◽  
pp. 120 ◽  
Author(s):  
Khalid Al Marazzeq ◽  
Malik Haddadin ◽  
Basem Al Abdullah ◽  
Malak Angor
Keyword(s):  
Sodium Nitrite ◽  
Leaf Extract ◽  
Sensory Attributes ◽  
Negative Control ◽  
Combined Effect ◽  
The Other ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Overall Acceptability ◽  
Olive Leaf Extract

<p>Six mortadella treatments were prepared for studying the effect of olive leaf extract (OLE) at a level of 240 mg OLE/100 g meat as nitrite alternative on the color and sensory characteristics. These treatments were: control with the addition of 120 ppm sodium nitrite only, and the second one with the addition of 240 mg OLE/100 g meat but without the addition of sodium nitrite as a negative control, the other four treatments were combination of 240 mg OLE/100 g meat with 80, 60, 40 and 20 ppm sodium nitrite, respectively. All samples were stored at 5 °C for 1, 3, 6, 9, and 12 weeks.<strong></strong></p><p>There were no significance differences (P &gt; 0.05) between all mortadella treatments regarding their proximate parameters.<strong> </strong>Hunter lightness (<em>L</em>), redness (<em>a</em>), and yellowness (<em>b</em>) color, and sensory attributes including the appearance, color, tenderness, juiciness, flavor, and overall acceptability showed that 80 and 60 ppm nitrite in combination with OLE at 240 mg/100 g meat had the best results in comparison with the other four treatments indicating an additive combined effect of the OLE with nitrite that enhanced mortadella characteristics.</p><p>These results revealed the ability to substitute 50% of the used nitrite in mortadella stored at 5 °C when using combinations of 60 ppm nitrite with 240 mg OLE/100 g meat.</p>

Evolution of the phenolic compounds profile of olive leaf extract encapsulated by spray-drying during in vitro gastrointestinal digestion

2019 ◽  
Vol 279 ◽  
pp. 40-48 ◽  
Author(s):  
Estefanía González ◽  
Ana María Gómez-Caravaca ◽  
Begoña Giménez ◽  
Rubén Cebrián ◽  
Mercedes Maqueda ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Spray Drying ◽  
Leaf Extract ◽  
Olive Leaf ◽  
Gastrointestinal Digestion ◽  
Olive Leaf Extract ◽  
In Vitro Gastrointestinal Digestion

scholarly journals Characterization and Bio-Accessibility Evaluation of Olive Leaf Extract-Enriched “Taralli”

Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1268 ◽  
Author(s):  
Annamaria Cedola ◽  
Carmen Palermo ◽  
Diego Centonze ◽  
Matteo Alessandro Del Nobile ◽  
Amalia Conte
Keyword(s):  
Antioxidant Capacity ◽  
Leaf Extract ◽  
Total Content ◽  
White Wine ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Ultrasound Assisted Extraction ◽  
Leaf Extracts ◽  
Digestion Process ◽  
Olive Leaf Extract

Olive leaves are rich in many compounds precious for human health. Due to this property, the current study was aimed to valorize the extract from this by-product in a cereal-based food, very popular all around the world, the “taralli”. To this aim, ultrasound-assisted extraction was applied to dried olive leaves to obtain the extract, used as “taralli” ingredient, instead of white wine. The “taralli” with and without extract was subjected to in vitro digestion to assess the quantity of polyphenolic compounds released in the gastrointestinal tract to become available for absorption. Total content of phenols and flavonoids, as well as the antioxidant capacity, was measured on both cooked and uncooked samples, before and after digestion. In addition, High-Performance Liquid Chromatography with Diode-Array Detection (HPLC-DAD) of the three most abundant polyphenols present in olive leaf extracts, such as oleuropein, hydroxytyrosol, and verbascoside, was carried out at the three stages of the digestion process. The results showed that the substitution of white wine with olive leaf extract increased the total content of polyphenols and flavonoids and the antioxidant capacity. Bio-accessibility of the main phenolic compounds demonstrated that oleuropein resisted slightly after gastric digestion but was almost completely degraded in the intestinal phase, while hydroxytyrosol and verbascoside were not resistant to the digestion process from the gastric phase.

scholarly journals Hepatoprotective Effect of Oleuropein-Rich Extract from Olive Leaves against Cadmium-Induced Toxicity in Mice

2020 ◽  
Vol 2020 ◽  
pp. 1-9 ◽  
Author(s):  
Hedya Jemai ◽  
Asma Mahmoudi ◽  
Anwar Feryeni ◽  
Ines Fki ◽  
Zouhaier Bouallagui ◽  
...  
Keyword(s):  
Leaf Extract ◽  
Cadmium Toxicity ◽  
Immunohistochemical Analysis ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Olive Leaf Extract ◽  
The Third ◽  
Liver And Kidney ◽  
Hepatoprotective Effects ◽  
Apoptosis And Inflammation

Cadmium (Cd) is a harmful pollutant which mainly affects the liver and kidney. In this work, we investigated the hepatoprotective effects of olive leaf extract based on oleuropein against hepatic cadmium toxicity in mice. Three groups of animals were used: the first one served as the control (C); the second one received intraperitoneal injection of cadmium 2 mg/kg b.w. (CD), administered five times during two weeks; and the third group received the same doses of Cd and simultaneously 16 mg/kg b.w. of oleuropein. Results showed that Cd induced a significant increase in liver injury biomarkers coupled with enhanced lipid peroxidation (MDA) and significant depletion of antioxidants (CAT and SOD). Histological and immunohistochemical analysis confirmed these findings. In fact, we observed a severe central lobular apoptosis and inflammation around central veins. Cotreatment with oleuropein significantly reduced the oxidative damage induced by cadmium. Our findings suggest that oleuropein could be used in the prevention of Cd hepatotoxicity.

scholarly journals Determination of the Variability of Bioactive Compounds and Minerals in Olive Leaf along an Agronomic Cycle

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2447
Author(s):  
María Esther Martínez-Navarro ◽  
Cristina Cebrián-Tarancón ◽  
Gonzalo L. Alonso ◽  
María Rosario Salinas
Keyword(s):  
Phenolic Compounds ◽  
Bioactive Compounds ◽  
Absolute Maximum ◽  
Olive Leaf ◽  
Olive Leaves ◽  
Absolute Minimum ◽  
Sunshine Hours ◽  
Agronomic Conditions ◽  
By Products

Olive leaves are still considered waste in the oil industry; however, the leaves have a content of oleuropein and other bioactive compounds that gives them great potential to be transformed into by-products. The most appropriate moment along an agronomic cycle (November 2019 to October 2020) has been evaluated to take advantage of this potential of the olive leaves varieties of Picual, Cornicabra and Manzanilla. In addition, factors that affect the content of phenolic compounds such as absolute maximum and minimum temperatures, relative humidity, sunshine hours, rainfall, differential of temperatures and mineral nutrition have been studied. The results show that the pruning season was the best time to take advantage of the olive leaf due to its high oleuropein content, especially in Picual and Manzanilla. The variety was the factor that most affected all the phenolic compounds studied, while the absolute minimum temperature factor notably affected verbascoside. Particular mineral nutrients, such as Mg and Fe, turned out to be most useful for differentiating locations. The content of verbascoside and hydroxytyrosol was also affected by agronomic conditions (location/conventional or ecological).

Sign in / Sign up

Export Citation Format

Share Document