In the present study, novel conjugated lignin/chitosan nanoparticles (LCNPs) were synthesized by a first-time simple green methodology using interfacial co-assembly between both biopolymers. The physicochemical (ζ-potential, size, concentration of surface acidic/basic groups), structural (surface functional groups), and morphological characteristics of the blank and quercetin-encapsulated (Q-LCNPs) nanoparticles were analyzed by the Boehm method, Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The experimentally determined encapsulation capacity was satisfactory—95.75%. The in vitro quercetin release efficiency in acidic solution that simulated the gastric microenvironment was 21.9%, followed by 68.5% and 99.8% cumulative release efficiency in simulated intestinal media at pH 7.4 and 6.8, respectively. The satisfactory applicability of the Weibull and sigmoidal mathematical models towards the experimental in vitro release data was indicative of the remarkable roles of diffusion and relaxation mechanisms.

Currently, marine algae are capturing the attention of both farmers and researchers eager to integrate sustainable methods to safeguard their crops. Instead of relying exclusively on synthetic pesticides, which often have negative environmental effects, some growers are now exploring algae-based products in hopes of reducing pest pressures. Various natural compounds sourced from algae—such as specific fatty acids and complex sugars—are believed to inhibit pest development, although their precise mechanisms are yet to be fully understood. Furthermore, there is some evidence suggesting that these compounds may bolster the plant’s own immune responses, thus enhancing crop resilience. Despite certain limitations on field applications, various techniques, including spraying, amending soil, or pre-treating seeds, are currently being evaluated. The results from the laboratory present a positive outlook, but implementing these discoveries to ensure consistent efficacy in practical settings is a major challenge. Variables such as climatic fluctuations, product durability, and formulation standards all elevate this complexity. In every instance, the approach of incorporating algae to lessen chemical dependence while securing uniform yields persists in being of interest, particularly in the area of organic or low-input farming.

Background/Objectives: The aim of the present study was to conduct a systematic in vitro assessment of the biofunctionalities of newly synthesized lignin (LNPs) and lignin–chitosan nanoparticles (LCNPs) via a comparative in vitro estimation of their cytotoxicity, cytocompatability potential, radical-scavenging activity, and antimicrobial performance, thereby establishing a benchmark for their sustainable design and biomedical applications. Methods: LNPs and LCNPs were synthesized via “green” self-assembly and co-assembly methods. Results: In vitro cytotoxicity studies on L929 fibroblasts and HaCaT keratinocytes demonstrated higher long-term viability for LCNPs (half-maximal inhibitory concentration IC₅₀ = 3.05 mg/mL at 72 h) compared with LNPs (IC₅₀ = 1.37 mg/mL), while both formulations maintained >76% viability at a concentration of 0.5 mg/mL. Electron Paramagnetic Resonance (EPR) and spectrophotometric antioxidant assays displayed strong radical scavenging activity, with LNPs excelling in ^●OH, NO, and ABTS scavenging and LCNPs exhibiting enhanced lipid peroxidation and superoxide inhibition potential. Antimicrobial testing revealed minimal inhibitory concentration (MIC) reductions of the nanoparticles up to 8–13-fold compared to lignin solutions, with LCNPs showing higher activity against Gram-positive and Gram-negative microbial strains. Conclusions: These results highlight LCNPs as biocompatible, antioxidant, and antimicrobial nanoplatforms with potential for regenerative medicine, oxidative stress mitigation, and infection control.

This study evaluates the impact of recirculating aquaponic cultivation on the biochemical, mineral, and antioxidant profiles of Swiss chard (Beta vulgaris var. cicla) integrated with Nile tilapia (Oreochromis niloticus), which serves as a source of nutrients through metabolic waste transformation within the system. Water quality parameters and microbiological testing confirmed efficient nitrification and system safety, with no Escherichia coli detected. Results showed that aquaponic cultivation yields a high nutritional value of Swiss chard, yielding high crude protein (31.4% DW) and mineral-rich biomass (ash 22.8% DW). Substantial concentrations of essential elements were recorded, including Ca, Mg, Fe (253.7 mg/kg DW), Zn, and Cu, suggesting high ionic bioavailability in the recirculating system. Physiological stability was reflected by a chlorophyll a content of 4.74 mg/g DW. Furthermore, the plants exhibited a robust phytochemical profile, with total phenolics (4.13 mg GAE/g DW) and flavonoids (5.18 mg QE/g DW) driving strong antioxidant activity (93.1% ABTS inhibition). These findings demonstrate that integrated aquaponic systems function as effective nutrient bioreactors, supporting high plant functional quality while supporting sustainable food production. The results validate aquaponics as a viable, climate-smart strategy for high-quality leafy vegetable cultivation within a circular bioeconomy framework.

Aquaponics is an integrated and resource-efficient production system that combines aquaculture and hydroponics in a closed-loop environment with reduced water consumption and nutrient losses. The present study evaluated the nutritional composition, mineral profile, microbiological quality, and antioxidant-related phytochemical characteristics of red amaranth (Amaranthus cruentus L.) cultivated in a recirculating aquaponic system under controlled environmental conditions. Leaf biomass was analyzed for proximate composition, macro- and micronutrient content, total phenolic and flavonoid compounds, betalains, chlorophyll pigments, and antioxidant activity using standard analytical and spectrophotometric methods. The results demonstrated high crude protein content and substantial accumulation of essential minerals, particularly calcium, potassium, and magnesium. The analyzed biomass also exhibited elevated levels of phenolic compounds, flavonoids, betalains, and chlorophyll pigments associated with considerable antioxidant potential. The pigment profile suggested good physiological adaptation of plants to aquaponic cultivation conditions. In addition, microbiological analysis confirmed acceptable hygienic quality and safety of the harvested plant material. Overall, the findings indicate that red amaranth can be successfully cultivated in aquaponic systems while maintaining high nutritional value and functional food potential. The study highlights aquaponic cultivation as a sustainable approach to producing nutrient-dense leafy vegetables within environmentally responsible agricultural systems.