title: Influence of olive leaf processing on the bioaccessibility of bioactive polyphenols.
abstract: Olive leaves are rich in bioactive compounds, which are beneficial for humans. The objective of this work was to assess the influence of processing conditions (drying and extraction) of olive leaves on the extract's bioaccessibility. Thus, extracts obtained from dried olive leaves (hot air drying at 70 and 120 °C or freeze-drying) by means of conventional or ultrasound-assisted extraction were subjected to in vitro digestion. Antioxidant capacity, total phenolic content, and HPLC-DAD/MS/MS analysis were carried out during digestion. The dehydration treatment used for the olive leaves did not have a meaningful influence on bioaccessibility. The digestion process significantly (p<0.05) affected the composition of the extracts. Oleuropein and verbascoside were quite resistant to gastric digestion but were largely degraded in the intestinal phase. Nevertheless, luteolin-7-O-glucoside was the most stable polyphenol during the in vitro simulation (43% bioaccessibility). Therefore, this compound may be taken into consideration in further studies that focus on the bioactivity of olive leaf extracts.
authors.affiliation: Grupo de Análisis y Simulación de Procesos Agroalimentarios (ASPA), Departamento de Tecnologı́a de Alimentos, Universitat Politècnica de València , Valencia 46022, Spain.
authors.forename: Margarita H
authors.initials: MH
authors.lastname: Ahmad-Qasem
authors.forename: Jaime
authors.initials: J
authors.lastname: Cánovas
authors.forename: Enrique
authors.initials: E
authors.lastname: Barrajón-Catalán
authors.forename: José E
authors.initials: JE
authors.lastname: Carreres
authors.forename: Vicente
authors.initials: V
authors.lastname: Micol
authors.forename: José V
authors.initials: JV
authors.lastname: García-Pérez
mesh_terms: D000383:Agriculture / Q000191:economics; D000975:Antioxidants / Q000032:analysis / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism*; D019587:Dietary Supplements / Q000032:analysis / Q000191:economics; D004063:Digestion; D005511:Food Handling; D005960:Glucosides / Q000032:analysis / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D006868:Hydrolysis; D007220:Industrial Waste / Q000032:analysis / Q000191:economics; D057888:Iridoid Glucosides; D039823:Iridoids / Q000032:analysis / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism; D047311:Luteolin / Q000032:analysis / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism; D008954:Models, Biological; D031658:Olea / Q000737:chemistry*; D010636:Phenols / Q000032:analysis / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism; D064209:Phytochemicals / Q000032:analysis / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry / Q000191:economics / Q000302:isolation & purification / Q000378:metabolism*; D018515:Plant Leaves / Q000737:chemistry*; D013030:Spain; D059808:Polyphenols
chemical_list: D000975:Antioxidants; D005960:Glucosides; D007220:Industrial Waste; D057888:Iridoid Glucosides; D039823:Iridoids; D047311:Luteolin; D010636:Phenols; D064209:Phytochemicals; D010936:Plant Extracts; C002769:oleuropein; C058956:acteoside; D059808:Polyphenols; C066408:luteolin-7-glucoside
keywords: Olea europaea; antioxidant potential; byproduct; drying; in vitro digestion