Adrian Drescher, Lisa Schwingshackl and Marlene Kienberger
High quantities of biomass produced in greenhouses create environmental problems as this side stream, and its downgraded products are not further used in the production cycle. The aim of our research was the identification and semi-quantification of molecules extracted from vegetative tomato plant residues with sustainable green alternative solvents using vacuum-assisted soxhlet and solid–liquid extraction to evaluate the possibilities for high-value applications for the first time. To identify compounds, gas chromatography–mass spectrometry (GC–MS) analysis and the Folin–Ciocalteau method were used. In sum, 285 different compounds have been assigned to 383 detected peaks using GC–MS analysis. The solvents 2-methyltetrahydrofuran (2-MTHF) and ethyl acetate, compared with ethanol and hexane, provided better results with a maximum number of 99 ± 8.83 compounds, a maximum total concentration of 5894.82 ± 586.48 and 3363.02 ± 71.14 mg naphthalene equivalent (NEQ) kgdw−1, and a total phenolic content of 2143.25 ± 155.17 and 1605.92 ± 66.46 mg gallic acid equivalent (GAE) kgdw−1, respectively. With 781.2 ± 112.66 and 718.25 ± 54.89 mg NEQ kgdw−1, the compound neophytadiene was the most common terpene in ethyl acetate and 2-MTHF extracts, respectively. It can be concluded that vegetative tomato plant residues contain a large variety of bioactive molecules. Green solvents, such as 2-MTHF and ethyl acetate, enhance the extraction of these molecules from the solid matrix.
Biomass Conversion and Biorefinery, 2024