Intensification of Polyphenol Extraction from Olive Leaves Using Ired-Irrad®, an Environmentally-Friendly Innovative Technology

Abstract

Optimization of infrared-assisted extraction was conducted using Response Surface Methodology (RSM) in order to intensify polyphenol recovery from olive leaves. The extraction efficiency using Ired-Irrad®, a newly-patented infrared apparatus (IR), was compared to water bath (WB) conventional extraction. Under optimal conditions, as suggested by the model and confirmed experimentally, the total phenolic content yield was enhanced by more than 30% using IR as contrasted to WB, which even required 27% more ethanol consumption. High Performance Liquid Chromatography analyses quantified the two major phenolic compounds of the leaves: Oleuropein and hydroxytyrosol, which were both intensified by 18% and 21%, respectively. IR extracts increased the antiradical activity by 25% and the antioxidant capacity by 51% compared to WB extracts. On the other hand, extracts of olive leaves obtained by both techniques exhibited equal effects regarding the inhibition of 20 strains of Staphylococcus aureus, with a minimum inhibitory concentration (MIC) varying between 3.125 and 12.5 mg/mL. Similarly, both extracts inhibited Aflatoxin B1 (AFB1) secretion by Aspergillus flavus, with no growth inhibition of the fungus. Finally, optimization using RSM allowed us to suggest other IR operating conditions aiming at significantly reducing the consumption of energy and solvent, while maintaining similar quantity and quality of phenolic compounds as what is optimally obtained using WB.

Techniques and modeling of polyphenol extraction from food: a review

“…Hydrogen bonding interactions and phase behaviors play a key role in studying this process Agri-food wastes Mouratoglou et al ( 2016 ) Infrared irradiation technology One of clean energy sources for improved extraction of natural products and bioactive compounds using a ceramic infrared emitter. Entire extraction requires low energy, easy to use, economical and has a great potential for scaleup Pomegranate, olive, apricot pomace Abi-Khattar et al ( 2019 ); Rajha et al ( 2019 ) Rapid solid–liquid dynamic extraction An innovative solid–liquid cyclic pressurization process involving the rapid extraction of polyphenols from their organic or inorganic solvent mixtures. The technique uses liquid pressure and takes place at room temperature (or slightly lower) in order to avoid thermal stress on phenolic compounds.…”

Innovative Extraction Techniques Using Deep Eutectic Solvents and Analytical Methods for the Isolation and Characterization of Natural Bioactive Compounds from Plant Material

“…According to the results, extracts obtained with the proposed Ired-Irrad method showed the highest antioxidant and antibacterial activity compared to extracts obtained with UAE and classical SLE. The IR technology is based on the heating of the plant material by IR radiation which, in combination with a suitable solvent results in selective extraction of the target compounds [152,153]. However, only a limited number of papers on this topic have been published so far, mostly by a single research group, and additional investigation is certainly needed to assess the true potential of this methodology.…”

Innovation in cannon puffing technology for the homogenization of bulk treatment: Half‐popped purple corn, a new healthy snack

“…The infrared apparatus (Ired-Irrad) was designed and patented in collaboration between the faculties of Sciences of Saint-Joseph University of Beirut (Lebanon) and the University of Balamand (Lebanon) (Abi-Khattar et al, 2019). It consists in exposing the kernels in a round bottom flask to infrared irradiation at 1 cm distance from an infrared ceramic emitter of 1,500 W (Rotfil, Pianezza, Italy).…”