Effectiveness of different solid-phase microextraction fibres for differentiation of selected Madeira island fruits based on their volatile metabolite profile—Identification of novel compounds

Abstract

a b s t r a c tA headspace solid-phase microextraction (HS-SPME) procedure based on five commercialised fibres (85 m polyacrylate -PA, 100 m polydimethylsiloxane -PDMS, 65 m polydimethylsiloxane/divinylbenzene -PDMS/DVB, 70 m carbowax/divinylbenzene -CW/DVB and 85 m carboxen/polydimethylsiloxane -CAR/PDMS) is presented for the characterization of the volatile metabolite profile of four selected Madeira island fruit species, lemon (Citrus limon), kiwi (Actinidia deliciosa), papaya (Carica papaya L.) and Chickasaw plum (Prunus angustifolia). The isolation of metabolites was followed by thermal desorption gas chromatography-quadrupole mass spectrometry (GC-qMS) methodology. The performance of the target fibres was evaluated and compared. The SPME fibre coated with CW/DVB afforded the highest extraction efficiency in kiwi and papaya pulps, while in lemon and plum the same was achieved with PMDS/DVB fibre. This procedure allowed for the identification of 80 compounds, 41 in kiwi, 24 in plums, 23 in papaya and 20 in lemon. Considering the best extraction conditions, the most abundant volatiles identified in kiwi were the intense aldehydes and ethyl esters such as (E)-2-hexenal and ethyl butyrate, while in Chicasaw plum predominate 2-hexenal, 2-methyl-4-pentenal, hexanal, (Z)-3-hexenol and cyclohexylene oxide. The major compounds identified in the papaya pulp were benzyl isothiocyanate, linalool oxide, furfural, hydroxypropanone, linalool and acetic acid. Finally, lemon was shown to be the most divergent of the four fruits, being its aroma profile composed almost exclusively by terpens, namely limonene, ␥-terpinene, o-cymene and ␣-terpinolene. Thirty two volatiles were identified for the first time in the fruit or close related species analysed and 14 volatiles are reported as novel volatile metabolites in fruits. This includes 5 new compounds in kiwi (2-cyclohexene-1,4-dione, furyl hydroxymethyl ketone, 4-hydroxydihydro-2(3H)-furanone, 5-acetoxymethyl-2-furaldehyde and ethanedioic acid), 4 in plum (4-hydroxydihydro-2(3H)-furanone, 5-methyl-2-pyrazinylmethanol, cyclohexylene oxide and 1-methylcyclohexene), 4 in papaya (octaethyleneglycol, 1,2-cyclopentanedione, 3-methyl-1,2-cyclopentanedione and 2-furyl methyl ketone) and 2 in lemon (geranyl farnesate and safranal). It is noteworthy that among the 15 volatile metabolites identified in papaya, 3-methyl-1,2-cyclopentanedione was previously described as a novel PPAR␥ (peroxisome proliferator-activated receptor ␥) agonist, having a potential to minimize inflammation.

Headspace solid‐phase microextraction combined with mass spectrometry as a powerful analytical tool for profiling the terpenoid metabolomic pattern of hop‐essential oil derived from Saaz variety

“…The temperature increases diffusion coefficients and Henry's constants while the time required to reach equilibrium decreases [54]. To evaluate the effect of temperature on SPME extraction efficiency, different extraction temperatures (24,30,40, and 50ЊC) were investigated. The results concerning total GC-qMS peak area as a function of temperature are illustrated in Fig.…”

“…This method, developed by Pawliszyn and co-workers [38,39], eliminates the use of organic solvents, and substantially shortens the time of analysis. SPME can integrate sampling, extraction, concentration, and sample introduction into a single uninterrupted process, resulting in high sample throughput and also be used as a solvent-free sample preparation method with gas chromatography (GC) mass spectrometry (MS) analysis, which has been successfully applied for profiling the metabolomic pattern of fruits [40][41][42][43][44], and analysis of environmental [45], food [40,42,44], forensic [46], and pharmaceutical samples [47] and also as a powerful technique for extraction of urinary potential cancer biomarkers [48,49].…”

Mass Spectrometry Strategies in Metabolomics

“…HS-SPME is a sensitive and robust technique. The effectiveness of various commercial HS-SPME fibers has recently been evaluated for the analysis of fruit volatiles and led to the identification of 14 novel volatiles (23). GC-MS-based analyses have also been used to identify volatile tomato repellents against whitefly (24) and to profile volatiles from various plant species, including tomato (25) and grape (26).…”

Effectiveness of high-throughput miniaturized sorbent- and solid phase microextraction techniques combined with gas chromatography–mass spectrometry analysis for a rapid screening of volatile and semi-volatile composition of wines—A comparative study

“…The theoretical foundations of SPME have been extensively addressed in the literature [29][30][31][32]. Since its development, this technique has become very popular and gained growing acceptance and increasing use in routine laboratories applications mainly to the sampling and analysis of environmental [33], food [34][35][36], forensic [37] and pharmaceutical samples [38,39]. Typically followed by GC in combination with mass spectrometric detection (MS) [40][41][42] or its multidimensional alternative, comprehensive two-dimensional GC (GC × GC-ToFMS) [43][44][45], SPME technique has been successfully used for wine samples.…”