Nutraceutical potential of Mediterranean agri-food waste and wild plants: Green extraction and bioactive characterization

The agricultural waste and wild plants of the Mediterranean region offer significant nutraceutical potential, rich in bioactive compounds such as phenolics, carotenoids, lipids and volatile organic compounds. These compounds exhibit health-promoting properties, including antioxidant, neuroprotective and anti-inflammatory effects. Advanced analytical techniques such as HPLC, GC-MS and NMR are essential for the accurate chemical characterization of these bioactives. Green extraction methods, including ultrasound-assisted, enzyme-assisted and cold plasma-assisted extractions, provide efficient and environmentally friendly alternatives to classical techniques for the isolation of bioactive compounds. The valorization of Mediterranean agricultural by-products, such as olive pomace, grape seeds, and citrus peels, exemplifies sustainable approaches to the utilization of these underutilized resources. This chapter explores the bioactive characterization and green extraction methods that contribute to unlocking the nutraceutical potential of Mediterranean plant waste and wild plants, highlighting their role in the development of functional foods and natural health products.

Strategies for the Management of Aggressive Invasive Plant Species

Current control methods for invasive alien plants (IAPs) have acceptable short-term outcomes but have proven to be unfeasible or unaffordable in the long-term or for large invaded areas. For these reasons, there is an urgent need to develop sustainable approaches to control or restrict the spread of aggressive IAPs. The use of waste derived from IAP control actions could contribute to motivating the long-term management and preservation of local biodiversity while promoting some economic returns for stakeholders. However, this strategy may raise some concerns that should be carefully addressed before its implementation. In this article, we summarize the most common methods to control IAPs, explaining their viability and limitations. We also compile the potential applications of IAP residues and discuss the risks and opportunities associated with this strategy.

Major Phytochemicals: Recent Advances in Health Benefits and Extraction Method

Recent scientific studies have established a relationship between the consumption of phytochemicals such as carotenoids, polyphenols, isoprenoids, phytosterols, saponins, dietary fibers, polysaccharides, etc., with health benefits such as prevention of diabetes, obesity, cancer, cardiovascular diseases, etc. This has led to the popularization of phytochemicals. Nowadays, foods containing phytochemicals as a constituent (functional foods) and the concentrated form of phytochemicals (nutraceuticals) are used as a preventive measure or cure for many diseases. The health benefits of these phytochemicals depend on their purity and structural stability. The yield, purity, and structural stability of extracted phytochemicals depend on the matrix in which the phytochemical is present, the method of extraction, the solvent used, the temperature, and the time of extraction.

Chemical and Functional Characterization of Extracts from Leaves and Twigs of Acacia dealbata

The purpose of this work was to evaluate the recovery of bioactive extracts from Acacia dealbata leaves and twigs and to characterize their chemical composition and functional properties. Fresh and air-dried samples were extracted by maceration at room temperature and by hot extraction at 60 °C using aqueous solutions of acetone, ethanol, and methanol. The highest extraction yields (14.8 and 12.0% for dried leaves and twigs, respectively) were obtained with 70% acetone, for both extraction procedures. Extracts were characterized for total phenolics content (TPC), total flavonoid content (TFC) and total proanthocyanidin content (TPrAC). Bioactive extracts with high TPC (526.4 mg GAE/g extract), TFC (198.4 mg CatE/g extract), and TPrAC (631.3 mg PycE/g extract) were obtained using maceration, a technically simple and low-energy process. The non-polar fraction of selected extracts was characterized using gas chromatography and time of flight mass spectrometry (GC-TOFMS). The main components detected were phytol, squalene, a-tocopherol, lupenone, and lupeol. The antioxidant activity of the extracts was characterized through DPPH and FRAP assays. Antimicrobial activity of the extracts against different bacteria was also determined. The highest DPPH and FRAP activities were obtained from dried twigs from Alcobaça (1068.3 mg TE/g extract and 9194.6 mmol Fe2+/g extract, respectively). Extracts from both leaves and twigs showed antimicrobial properties against Staphylococcus aureus, Staphylococcus epidermidis, methicillin resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Bacillus cereus, Streptococcus mutans, and Streptococcus mitis. The results obtained demonstrate the feasibility of recovering valuable components from these biomass fractions that may be further valorized for energy production in a biorefinery concept.

Valorization of Tomato Residues by Supercritical Fluid Extraction

Tomato processing leads to the production of considerable amounts of residues, mainly in the form of tomato skins, seeds and vascular tissues, which still contain bioactive molecules of interest for food, pharmaceutical and nutraceutical industries. These include carotenoids, such as lycopene and β-carotene, tocopherols and sitosterols, among others. Supercritical fluid extraction is well positioned for the valorization of tomato residues prior to disposal, because it remains an environmentally safe extraction process, especially when using carbon dioxide as the solvent. In this article, we provide an extensive literature overview of the research on the supercritical fluid extraction of tomato residues. We start by identifying the most relevant extractables present in tomatoes (e.g., lycopene) and their main bioactivities. Then, the main aspects affecting the extraction performance are covered, starting with the differences between tomato matrixes (e.g., seeds, skins and pulp) and possible pretreatments to enhance extraction (e.g., milling, drying and enzymatic digestion). Finally, the effects of extraction conditions, such as pressure, temperature, cosolvent, flow rate and time, are discussed.