In vivo extraction of volatile organic compounds (VOCs) from Micro-Tom tomato flowers with multiple solid phase microextraction (SPME) fibers

The in vivo headspace extraction of volatile organic compounds from Micro-Tom tomato flowers was investigated using multiple solid phase microextraction (SPME) fibers of different properties to maximize the extraction selectivity for a nontargeted analysis. The three fibers used in this work were polydimethylsiloxane (PDMS), PDMS/divinylbenzene (DVB), and carboxen (CAR)/PDMS. Two sources for tomato flowers were used: Micro-Tom wild type (WT) and transgenic Micro-Tom overexpressing the carotenoid cleavage deoxygenase 1 gene. Gas chromatography-mass spectrometry (GC-MS) results demonstrated that the largest amounts of volatile organic compounds (VOCs) were observed with the PDMS/DVB fiber for both wild type and transgenic plants, but the CAR/PDMS and PDMS fibers contributed to the detection of selective compounds. Data revealed the presence of 45 VOCs from transgenic plants and 35 from the wild type when all three fibers were used together. Of the total VOCs identified, 30 were common to both types of plants, but 15 were specific to the transgenic and 5 to the wild type plants. The compounds identified from Micro-Tom flowers were mainly monocyclic and bicyclic monoterpenes and sesquiterpenes, with one alkyl benzene compound. The bicyclic monoterpenes, (1R)-α-pinene, (1S)-α-pinene, and β-pinene, were found to be the most abundant molecules present in both wild type and transgenic plants. The overall advantage of maximizing the discovery of VOCs based on the selectivity differences with three SPME fibers was evident. Such a benefit is important in the nontargeted analysis of transgenic plants for detecting the production of unexpected compounds.