Harnessing the Potential of Walnut Leaves from Nerpio: Unveiling Extraction Techniques and Bioactivity Through Caenorhabditis elegans Studies

This study used Juglans regia leaves from the Gran Jefe variety; this indigenous cultivar from Nerpio is highly valued for its quality and distinct characteristics. This type of walnut is traditionally cultivated in the region and is noted for its organoleptic properties and adaptation to local clim...

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Bibliographic Details
Authors: Hamdi, Amel, Córdoba-Rojano, Miguel Angel, Monje, José Manuel, Guillén-Izquierdo, Elisa, Rodríguez-Arcos, Rocío, Jiménez-Araujo, Ana, Muñoz Ruiz, Manuel Jesús, Guillén-Bejarano, Rafael
Format: article
Publication Date:2025
Country:España
Institution:Universidad Pablo de Olavide (UPO)
Repository:RIO. Repositorio Institucional Olavide
Language:English
OAI Identifier:oai:rio.upo.es:10433/23789
Online Access:https://hdl.handle.net/10433/23789
Access Level:Open access
Keyword:Walnut leaves
Gran Jefe variety
Nerpio
Phenolic compounds
Extraction methods
Water
Ethanol 80%
Bioactivities
Free phenolics
C. elegans
Description
Summary:This study used Juglans regia leaves from the Gran Jefe variety; this indigenous cultivar from Nerpio is highly valued for its quality and distinct characteristics. This type of walnut is traditionally cultivated in the region and is noted for its organoleptic properties and adaptation to local climatic conditions. Two solvents were tested to determine the optimal extraction conditions for phenolic compounds: 80% ethanol and water. Direct homogenization with an Ultra-Turrax, direct ultrasound, and indirect ultrasound treatments were compared for ethanol extraction. Water extractions were conducted using direct and indirect ultrasound, infusion, and decoction. Compared to water extraction, 80% ethanol proved to be more efficient. Extracting phenolic compounds from ’Gran Jefe’ walnut leaves was most effective when using direct extraction methods without either ultrasound assistance or indirect ultrasound treatment. The main compounds identified were trans-3-caffeoylquinic acid and quercetin-3-hexoside isomer 1. The ethanolic extract obtained through direct extraction was selected to study further the bioactivities of ’Gran Jefe’ walnut leaves using C. elegans as an in vivo model. Results indicated that the leaf extract enhanced thermal and oxidative stress resistance, promoted fertility, and exhibited neuroprotective effects in models of Alzheimer’s and Parkinson’s diseases. The observed bioactivities were attributed to the free phenolics present in the ethanolic extract.