A 2‐D‐HPLC‐CE platform coupled to ESI‐TOF‐MS to characterize the phenolic fraction in olive oil

Abstract

A 2-D-HPLC/CE method was developed to separate and characterize more in depth the phenolic fraction of olive oil samples. The method involves the use of semi-preparative HPLC (C18 column 250x10 mm, 5 microm) as a first dimension of separation to isolate phenolic fractions from commercial extra-virgin olive oils and CE coupled to TOF-MS (CE-TOF-MS) as a second dimension, to analyze the composition of the isolated fractions. Using this method, a large number of compounds were tentatively identified, some of them by first time, based on the information concerning high mass accuracy and the isotopic pattern provided by TOF-MS analyzer together with the chemical knowledge and the behavior of the compounds in HPLC and CE. From these results it can be concluded that 2-D-HPLC-CE-MS provides enough resolving power to separate hundreds of compounds from highly complex samples, such as olive oil. Furthermore, in this paper, the isolated phenolic fractions have been used for two specific applications: quantification of some components of extra-virgin olive oil samples in terms of pure fractions, and in vitro studies of its anti-carcinogenic capacity.

Theoretical Study of the Hydrogenation Reactions between 1,2-diazene and Flavonoid Molecules

“…So we can say that the compound 3b (2R3R) is the thermodynamic product and compound 3'b(2S 3S) is the kinetic product of Our theoretical results clearly confirm the existence of stereoisomere 3b that is thermodynamically more stable than stereoisomeres 3'b(2S 3S), 3b 1 (2S 3R) and 3b 2 (2R3S). This explains well the existence of flavanone 3b in different plants [1][2][3][4] .…”

“…This confirms the existence of flavanone 3a(2R). However the existence of compound 3'a(2S) is not possible in nature [1][2][3][4] . Second, we determine the transition states of reaction between (Z)-1,2-diazene 2 and flavonol 1b in both approaches endo and exo.…”

Differential metabolomic analysis of the potential antiproliferative mechanism of olive leaf extract on the JIMT-1 breast cancer cell line

“…In fact, dietary antioxidants and phenolic compounds in particular have been associated with preventive effects against several diseases, such as cancer [2,3]. The past two decades have witnessed substantial progress in the identification of the biochemical events associated with the multistage process of carcinogenesis, and we are now aware of how certain dietary phytochemicals alter this process [4].…”

Separation of phenolic acids and flavone natural antioxidants by two‐dimensional method combining liquid chromatography and micellar electrokinetic capillary chromatography

“…On‐line connection of RPLC to CZE has been introduced by Bushey and Jorgenson 35 and further applied by Jorgenson's group 31, 36, 37. Off‐line connections of LC and CE have been described by several research groups 38, 39, 45. The off‐line approach is slower than the on‐line 2‐D methods, as it involves the collection of fractions from the first dimension and then the analysis of isolated fractions in the second dimension.…”

“…Garcia‐Villalba et al . used HPLC‐CE for the analysis of extra‐virgin olive oil samples 45. Selected fractions containing phenolic compounds were isolated for quantification and in vitro studies of anti‐carcinogenic capacity.…”