Analytica

In modern circular-economy value chains, wood is frequently processed into fines, chips, or powders—forms in which anatomical features are no longer visible, rendering traditional visual identification methods ineffective. This study introduces a rapid, non-destructive attenuated total reflection–Fourier transform infrared (ATR-FTIR) spectroscopy approach, combined with chemometric modeling, to address this challenge by enabling both the classification and compositional profiling of processed wood fractions. Using full-spectrum ATR-FTIR data, partial least squares discriminant analysis (PLS-DA) models achieved high-accuracy classification of wood by type, species, and provenance, with sensitivity and specificity reaching up to 1.00. In addition, PLS and backward interval BiPLS models predicted total lignin, acid-soluble lignin, and extractives with strong performance (R² > 0.90, RPD > 2). Interval selection further enhanced prediction accuracy by reducing RMSEP by up to 30%, improving model stability for real-world application. By replacing slow, reagent-intensive wet chemistry with a rapid, green, and scalable technique, the presented methodology provides a valuable tool for authentication, quality control, and resource optimization when dealing with mechanically processed or recycled wood.

In this study, an integrated analytical method coupling ultra-high-performance liquid chromatography–photodiode array detection–quadrupole time-of-flight mass spectrometry with total antioxidant capacity determination (UHPLC-PDA-Q-TOF/MS-TACD) was developed for the rapid screening and identification of antioxidants in complex natural extracts. The system enables simultaneous chromatographic separation, mass spectrometric characterization, and on-line activity assessment by combining 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and ferric ion reducing antioxidant power (FRAP) assays. When applied to Rosa rugosa samples from five different origins, the approach efficiently separated the extract and successfully localized antioxidants directly from the chromatographic profile. A total of 86 compounds were identified, including flavonoids, tannins, and phenolic acids. Among them, 60 exhibited free radical scavenging capacity and 59 showed reducing activity. Activity verification experiments showed that all seven compounds exhibited good antioxidant activity. The IC₅₀ values of gallic acid, ellagic acid, quercetin 3-O-rhamnoside, and rutin were 0.019, 0.025, 0.043, and 0.046 mM, respectively, which were significantly better than the positive control (vitamin C). This method provides methodological and technical support for the rapid discovery of antioxidant components in complex natural products.

In recent years, research and development in the field of green extraction of bioactive compounds from plants has intensified. This increased focus is driven by market trends, environmental concerns, and consumers’ growing interest in natural and healthy ingredients, as well as bioactive compounds. This development aligns with a global trend toward more sustainable use of natural resources. In this context, macroalgae have been recognized as valuable sources of bioactive compounds with various health benefits. These molecules include proteins, fatty acids, vitamins, and pigments. Phycobiliproteins (PBPs) are pigments and metabolites of particular interest that can be extracted from microalgae. This group of colored proteins, mainly present in cyanobacteria and red algae, is known to have a wide range of potential applications. However, conventional methods for extracting PBPs, such as homogenization, maceration, and freezing, are time-consuming and energy-intensive, often producing unsatisfactory yields. As a result, new extraction technologies have been developed, including ultrasound-assisted extraction, ionic liquid extraction methods, and the use of natural deep eutectic solvents. This review summarizes existing green processes for extracting and purifying PBPs, with the aim of enabling feasible and sustainable valorization of algae. Specifically, it covers various extraction and purification techniques of PBPs, as well as the effects of environmental growth conditions on the production of these metabolites. It also highlights the biological and pharmacological activities of PBPs and explores their potential applications in the food, cosmetic, and biomedical sectors.