Isolation of a hydroxytyrosol lactone conjugate from olive mill waste water with antioxidant activity

• Published in: Planta Medica
• Main Authors: Vougogiannopoulou, K, Pratsinis, H, Grougnet, R, Halabalaki, M, Kletsas, D, Deguin, B, Skaltsounis, L
• Format: Conference Proceeding
• Language: English
• Published: 30.10.2014
• ISSN: 0032-0943; 1439-0221
• DOI: 10.1055/s-0034-1394715

Olive mill waste water (OMWW) is the major byproduct of olive oil industry with destructive impact to the environment, ranging from aesthetic devalorization of countryside to severe genetic toxicity to eukaryotic organisms. Nevertheless, OMWW is a valuable source of high added value products such as hydroxytyrosol ( 1 ) and lactones deriving from the secoiridoid core of olive constituents ( 2 ) [1]. Under the context of revealing the elusive non-phenolic substances present in OMWW, we proceeded with the investigation and qualitative characterization of an enriched extract of OMWW, which resulted in the isolation and structural characterization of seven secoiridoid lactones, through fast centrifugal partition chromatography (FCPC) separation. Structural elucidation of the isolated compounds was performed with the aid of 1D and 2D NMR and mass spectroscopy. Among the isolates, lactone 3 is a new derivative characterized by the ester linkage of hydroxytyrosol with lactone 2 . Although the lactone content of OMWW has been investigated in the past, it is the first time that a lactone derivative bearing a hydroxytyrosol moiety is found. Additionally, the antioxidant capacity of compounds 1 , 2 and 3 was studied at a cellular level using human skin fibroblasts in the well known DCFH-DA assay where 3 showed an activity similar to equimolar concentrations of Trolox. References: 1. Agalias A, Magiatis P, Skaltsounis AL, Mikros E, Tsarbopoulos A, Gikas E, Spanos I, Manios T. A new process for the management of olive oil mill waste water and recovery of natural antioxidants. J Agric Food Chem 2007; 55: 2671 – 2676. 2. Zoidou E, Agalias A, Magiatis P, Skaltsounis AL. New iridoid derivatives from table olives cv 'Throuba Thassos'and olive mill waste waters. Planta Med 2008; 74: PB168