Squalene oxidation products: Monitoring the formation, characterisation and pro-oxidant activity

Naziri, E; Consonni, R; Tsimidou, MZ

HERO ID

4969066

Reference Type

Journal Article

Year

2014

HERO ID 4969066
In Press No
Year 2014
Title Squalene oxidation products: Monitoring the formation, characterisation and pro-oxidant activity
Authors Naziri, E; Consonni, R; Tsimidou, MZ
Journal European Journal of Lipid Science and Technology
Volume 116
Issue 10 (Oct 2014)
Page Numbers 1400
Abstract   Squalene (SQ), a precursor of sterols and terpenoids is a functional lipid of high importance in the food and pharmaceutical sectors. SQ oxidation studies are rather limited compared with those for other olefins. The aim of the present study was to monitor the formation of SQ oxidation products under different conditions (temperature, air supply), to characterise the most abundant of them by spectroscopic techniques and then examine their pro-oxidant activity in a model lipid substrate. Squalane (SQA), the saturated analogue of SQ, was used as a reference compound. FT-MIR analysis indicated the presence of alcohols, epoxides, aldehydes, and ketones. GC-MS was used to characterise SQ primary oxidation and scission products. The presence of epoxides was further confirmed by means of 1H NMR and 13C NMR spectroscopy. It could be argued that SQ stability is due to its stereochemistry and specifically to the presence of methyl groups next to the double bonds. The pro-oxidant activity of SQ oxidation products was evident at 62 and 40°C and suppressed only in the presence of primary antioxidants, not of SQ. The present work adds to the characterisation of SQ oxidised products. To our knowledge their pro-oxidant activity has never been examined before. Practical applications: Characterisation of squalene oxidation products and assessment of their activity as pro-oxidants present both scientific interest regarding the kinetics and product identity as well as a practical impact in case this bioactive lipid is provided for consumption as a functional product. In the past, cholesterol oxidation products and more recently phytosterol ones attracted the interest of researchers, who studied the stability of the respective parent compounds for food safety reasons. Monitoring of the formation of SQ oxidation products under different conditions (temperature, air supply) and chemical characterisation of the most abundant of them by spectroscopic techniques. Examination of their pro-oxidant activity in a model lipid substrate. Squalene may exert a weak antioxidant activity due to competitive oxidation phenomena with the lipid substrate while its oxidation products have a pro-oxidant activity on purified olive oil model substrate that was suppressed only in the presence of primary antioxidants. [PUBLICATION ABSTRACT]
Doi 10.1002/ejlt.201300506
Wosid WOS:000342773300016
Is Certified Translation No
Dupe Override No
Is Public Yes
Keyword NMR; Olive oil; Squalene; Squalene oxidation products; Squalene epoxides