Table 3.
Examples of plant waste extracted with conventional and non-conventional methods and analysed by liquid chromatography-mass spectrometry with the identification of different classes of compounds.
| Plant Waste | Extraction Methods | Analytical Techniques | Bioactive Compounds |
Ref. |
|---|---|---|---|---|
| Wine lees | Maceration followed by microfiltration step | UHPLC-LTQ Orbitrap and Velos LC-QTrap 4000 | Phenolic compounds | [91] |
| Olive leaves | Organo-solv extraction | LC-Finnigan AQA | Polyphenols | [92] |
| Tomato pomace | Maceration | LC-Q-Exactive | Polyphenols | [93] |
| Spent black tea | Pressurised liquid extraction | LC-LTQ-Orbitrap XL | Phenolic compounds | [94] |
| Aloe vera leaf | UAE and MAE extractions | LC/MS single quadrupole | Anthraquinone and chromone derivatives | [95] |
| Olive mill wastewater | Liquid-liquid extraction | LC-QTRAP 6500 | Polyphenols | [58] |
| Saffron tepals | Enzymatic and subcritical water extractions | LC-LTQ XL linear ion trap | Flavonoids | [96] |
| Red cabbage waste | Pressurized liquid extraction (PLE), ultrasound-assisted extraction (UAE), and heating and stirring extraction (HSE) | LC-Linear Ion Trap | Anthocyanyns | [99] |
| Annatto by-product | Maceration | UPLC-MS/QTOF Analysis | Terpenoids, ceramides | [41] |
| flower P. serrulata | Maceration | LC-Q-Trap 6500 in MRM mode | Anthocyanins | [64] |
| Plum seed residue | Matrix solid-phase dispersion | HPLC-ESI-QTOF-MS | Phenolic compounds | [37] |
| Walnut husk and pellicle | Ultrasound | UHPLC-Q-Exactive | Flavonoids, tannins and quinones | [38] |
| Chia leaves | Maceration | UHPLC-Q-Exactive | Polyphenols | [39] |
| Peach by-product | Extraction with enzyme (EAE) | UPLC-Qexactive | Phenolic acid Flavonoids |
[40] |
| Mustard, kale, and broccoli microgreens | Maceration | UHPL-Fusion Orbitrap | Flavonoids | [43] |
| Foxnut | Maceration | LC-Orbitrap eclipse | Lipids, amino acids, phenolic acid Flavonoids alkaloids |
[44] |
| Roots of red beet and sugar beet | Maceration | LC-LTQ XL linear ion trap | Betalins Phenolic compounds |
[59] |
| Peel of Citrus retigulata | Ultrasound extraction | LC-Q-Exactive | Flavonoids | [63] |
| Fennel waste | Ultrasound extraction | UPLC-Qtrap 6500 | Flavonoids | [66] |
| Apple cider by-products | Maceration | LC-Q-TOF | Carotenoids, phenols | [85] |
| Tamarillos | Maceration | LC-APCI-MS/MS | Carotenoids | [100] |
| Red pepper skin | Maceration | LC-Q-Exactive | Carotenoids | [102] |
| Avocado | Maceration | UHPLC-Q-Tof | Phenolic acids | [108] |
| Mango peel | Maceration | LC-ESI-MS | Polyphenols | [109] |