Development of Analytical Strategies for the Determination of Olive Fruit Bioactive Compounds Using UPLC-HRMS and HPLC-DAD. Chemical Characterization of Kolovi Lesvos Variety as a Case Study

Abstract

In this study, an overall survey regarding the determination of several bioactive compounds in olive fruit is presented. Two methodologies were developed, one UPLC-Q-TOF-MS method for the determination of olive fruit phenolic compounds and one HPLC-DAD methodology targeting the determination of pigments (chlorophylls and carotenoids), tocopherols (α-, β, -γ, δ-) and squalene. Target and suspect screening workflows were developed for the thorough fingerprinting of the phenolic fraction of olives. Both methods were validated, presenting excellent performance characteristics, and can be used as reliable tools for the monitoring of bioactive compounds in olive fruit samples. The developed methodologies were utilized to chemical characterize the fruits of the Kolovi olive variety, originating from the island of Lesvos, North Aegean Region, Greece. Twenty-five phenolic compounds were identified and quantified in Kolovi olives with verbascoside, hydroxytyrosol, oleacein and oleomissional found in significantly high concentrations. Moreover, 12 new bioactive compounds were identified in the samples using an in-house suspect database. The results of pigments analysis suggested that Kolovi variety should be characterized as low pigmentation, while the tocopherol and squalene content was relatively high compared to other olive varieties. The characterization of Kolovi olive bioactive content highlighted the high nutritional and possible economic value of the Kolovi olive fruit.

Phytochemical Profiling by UPLC‐ESI‐QTOF‐MS of Kalaharia uncinata (Schinz) Moldenke, Widely Used in Traditional Medicine in DR Congo

“…Other characteristic signals were observed at m/z 529, 487, 459 (loss of caffeoyl/hexose/162 Da from m/z 621), 179 (after consecutive losses of deoxyhexose=146 Da and hexose/caffeoyl=162 Da from m/z 487), 161 (after a loss of H 2 O=18 Da, from m/z 179) and 151 (after consecutive losses of hexose/caffeoyl=162 Da, and deoxyhexose=146 Da from m/z 459). The presence of a fragment ion at m/z 477 (after the loss of hexose or caffeoyl=162 Da, from m/z 639) could be consistent with β ‐hydroxyacteoside [27] being compound 4 and the absence of this fragment ion could indicate suspensaside [27–31] being compound 7 (Figure 3).…”

“…[19,[22][23][24] The high intensity of the ion at m/z 193 and the lack of a signal at m/z 211 observed upon fragmentation, most likely indicates secologanic acid [19] (Figure 2). [20,32,54,55] The mass spectrum of both compounds The presence of a fragment ion at m/z 477 (after the loss of hexose or caffeoyl = 162 Da, from m/z 639) could be consistent with β-hydroxyacteoside [27] being compound 4 and the absence of this fragment ion could indicate suspensaside [27][28][29][30][31] being compound 7 (Figure 3). [56][57][58] The presence of this ion is, according to the same authors, an indication of the 7-O position of glycosylation.…”

Monitoring the Phenolic and Terpenic Profile of Olives, Olive Oils and By-Products throughout the Production Process

“…These compounds were hydroxytyrosol (phenolic alcohol), luteolin (flavonoid), 6 isomers of oleuropein aglycone, oleacein and 5 isomers of ligustroside aglycone (secoiridoids), elenolic acid and its decarboxymethylated derivative. Although their presence in olive oil is probably due to the hydrolysis that occurs in the sample treatment for technological oil extraction, some of them have been described as olive fruit components in the literature [50,57].…”

Phytochemicals Derived from Agricultural Residues and Their Valuable Properties and Applications

“…The cultivation of olive trees is a widespread practice in the Mediterranean region, accounting for about 98% of the world’s olive cultivation. A large number of phenolic compounds occur in both olive oil and olive waste that includes both leaves and the residues of oil production [ 275 , 276 ]. Their chemical characterization was reported by Dermeche et al [ 277 ].…”