Pressurized liquid extraction of brewer’s spent grain: Kinetics and crude extracts characterization

Validation of a Rapid Ultrasound-Assisted Extraction Coupled with Anion Exchange Chromatography Method for the Determination of D-Psicose in Raisin Matrices

D-psicose is a rare sugar, used as an alternative to the natural sweetener that provides 70% of sucrose’s sweetness, with low-calorie absorption in the human body. Considering the health-beneficial effect and high availability of D-psicose in raisins (the world’s most consumed dried fruit), it is of interest to establish a reliable analytical method to determine D-psicose content in these matrices. Herein, a new method for determining D-psicose content in raisins, using ultrasound-assisted extraction in conjunction with anion exchange chromatography with pulsed amperometric detection (UAE-HPAEC-PAD) systems, has been developed and validated. The stability of D-psicose and its precursor was priorly assessed by applying a specific ultrasound power (100 W) and pulse duty cycle (0.5 s−1), with varying extraction temperatures (10, 25, 40, 55, 70, and 85 °C) and times (5, 10, 15, 20, and 25 min). The method was validated with high linearity (R2 > 0.999), accuracy (89.78–101.06%), and precision (4.8% intra-day and 4.34% inter-day). A number of raisin products were checked during the method applicability assessment. A concentration of 520 mg kg−1 was found in a specimen of commercial raisin matrix.

Investigation of the Genotoxic, Antigenotoxic and Antioxidant Profile of Different Extracts from Equisetum arvense L

The present study investigated the cyto-genotoxic and antigenotoxic effects of four different extracts of Equisetum arvense L. (common name: field horsetail) on human lymphocytes. Specifically, Soxhlet’s prepared extracts from E. arvense L., using different solvents (S1: methanol (MeOH)-, S2: ethanol (EtOH)-, S3: water-, and S4: ethanol/water (EtOH-W)-) were analyzed for (a) their total phenolic and flavonoid content (TPC and TFC, respectively), (b) their antioxidant activity (AA), via the DPPH, FRAP and ABTS assays, and (c) their cyto-genotoxic and/or protective efficiency against the mutagenic agent mitomycin C, via the Cytokinesis Block MicroNucleus assay. All extracts showed increased TPC, TFC, and AA values in almost all cases. S1, S3 and S4 demonstrated no cytotoxic potential, whereas S2 was cytotoxic only at the highest concentrations. Genotoxicity was not observed in the tested extracts. The highest antigenotoxic activity was observed for EtOH-W (S4) extract, which was found to be rich in flavonoids, flavonoid-O-glycosides, phytosterols, phenolic and fatty acids as well as in minerals and mainly in K, Ca, Mg, Si and P, as assessed by using various mass spectrometry techniques. Those findings confirm that E. arvense L. extracts could be valuable candidates for medicinal applications and pharmaceutical products, thus alleviating the effects of more conventional drugs.

High-Pressure Technologies for the Recovery of Bioactive Molecules from Agro-Industrial Waste

Large amounts of food waste are produced each year. These residues require appropriate management to reduce their environmental impact and, at the same time, economic loss. However, this waste is still rich in compounds (e.g., colorants, antioxidants, polyphenols, fatty acids, vitamins, and proteins) that can find potential applications in food, pharmaceutical, and cosmetic industries. Conventional extraction techniques suffer some drawbacks when applied to the exploitation of food residues, including large amounts of polluting solvents, increased time of extraction, possible degradation of the active molecules during extraction, low yields, and reduced extraction selectivity. For these reasons, advanced extraction techniques have emerged in order to obtain efficient residue exploitation using more sustainable processes. In particular, performing extraction under high-pressure conditions, such as supercritical fluids and pressurized liquid extraction, offers several advantages for the extraction of bioactive molecules. These include the reduced use of toxic solvents, reduced extraction time, high selectivity, and the possibility of being applied in combination in a cascade of progressive extractions. In this review, an overview of high-pressure extraction techniques related to the recovery of high added value compounds from waste generated in food industries is presented and a critical discussion of the advantages and disadvantages of each process is reported. Furthermore, the possibility of combined multi-stage extractions, as well as economic and environmental aspects, are discussed in order to provide a complete overview of the topic.