Abi-Khattar Anna-Maria, Rajha Hiba N, Abdel-Massih Roula M, Maroun Richard G, Louka Nicolas, Debs Espérance
Centre d'Analyses et de Recherche, Unité de Recherche Technologies et Valorisation Agro-alimentaire, Faculté des Sciences, Université Saint-Joseph, B.P. 17-5208 Riad El Solh, Beirut 1104 2020, Lebanon.
Department of Biology, University of Balamand, Tripoli, P. O. Box 100, Lebanon.
Antioxidants (Basel). 2019 Jul 18;8(7):227. doi: 10.3390/antiox8070227.
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 with a minimum inhibitory concentration (MIC) varying between 3.125 and 12.5 mg/mL. Similarly, both extracts inhibited Aflatoxin B1 (AFB1) secretion by , 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.
采用响应面法（RSM）对红外辅助提取进行优化，以提高从橄榄叶中回收多酚的效率。将使用新型专利红外设备（IR）Ired-Irrad的提取效率与水浴（WB）常规提取进行了比较。在模型建议并经实验证实的最佳条件下，与WB相比，使用IR时总酚含量产量提高了30%以上，而WB甚至需要多消耗27%的乙醇。高效液相色谱分析对叶片中的两种主要酚类化合物进行了定量：橄榄苦苷和羟基酪醇，它们的含量分别提高了18%和21%。与WB提取物相比，IR提取物的抗自由基活性提高了25%，抗氧化能力提高了51%。另一方面，两种技术获得的橄榄叶提取物对20株菌株的抑制效果相同，最低抑菌浓度（MIC）在3.125至12.5mg/mL之间。同样，两种提取物都抑制了黄曲霉毒素B1（AFB1）的分泌，且对真菌没有生长抑制作用。最后，使用RSM进行优化使我们能够提出其他IR操作条件，旨在显著降低能源和溶剂消耗，同时保持与WB最佳提取时相似数量和质量的酚类化合物。
