Effect of Geographical Location on the Phenolic and Mineral Composition of Chetoui Olive Leaves

Abstract

In this study, we investigated the influence of pedological parameters and variation of altitude on the mineral nutrients, phenolic compounds, and antioxidant activities of olive leaves. Samples of the Chetoui cultivar were collected from eight geographical locations with different altitudes. Levels of phenolic compounds varied according to the altitude. Classification of the locations revealed that altitude 1 (>500 m) was characterized by high levels of secoiridoids and simple phenols, while altitude 2 (500–300 m) and altitude 3 (<300 m) were higher in flavonoids. Levels of Mn, Ca and B in the leaves and level of Zn in the soil were significantly correlated with the abundance of oleuropein and luteolin-7-O glucoside, the most important phenols in Chetoui olive leaves. The results suggest that, in addition to pedological criteria, environmental conditions also influence the formation of phenolic compounds.

Valorization of Olive Leaf Polyphenols by Green Extraction and Selective Adsorption on Biochar Derived from Grapevine Pruning Residues

“…The main compound found in olive leaves was oleuropein, which is in accordance with previous results [43][44][45][46]. Accordingly, the sum of polyphenols performed similarly to oleuropein.…”

Amino Acids Biostimulants and Protein Hydrolysates in Agricultural Sciences

“…Food-derived bioactive proteins have physiological impacts on major body systems, such as opioid agonists and opioid antagonists on the nervous system; anti-hyperlipidemic, anti-thrombotic, anti-oxidative, and anti-hypertensive effects on the cardiovascular system; cytomodulatory, immunomodulatory, and anti-microbial effects on the immune system; and mineral binding, anti-appetizing, and anti-microbial impacts on the gastrointestinal system [ 46 , 47 , 48 , 49 , 50 ]. Phenols have notable roles in plant development and growth [ 51 , 52 , 53 ], as they are products of secondary metabolic procedures and are generally converted from sugars via the pentose phosphate pathway, the manganiferous acid pathway, the glycolytic pathway, or the benzene-propane pathway [ 54 , 55 , 56 ]. Phenolic acids include a carboxylic acid group in addition to the basic phenolic structure and are categorized into hydroxybenzoic and hydroxycinnamic acids.…”

Preventing Microbial Growth in Game Meat by Applying Polyphenolic Extracts from Olive Mill Vegetation Water

“…Polyphenols are also evaluated after being mixed with other molecules or adsorbed onto coating agents [ 12 , 13 ]. Different polyphenols are present in olive leaves and fruits, and their amounts change according to geographical localization, cultivar, and season [ 14 , 15 ]. Although the olive fruit contains a high concentration of phenolic compounds, only 2% of them are found in the oil phase.…”