Nelson Marmiroli

Introduction: Utilizing agri-food by-products and residues to create soil improvers reduces waste and promotes environmentally friendly agriculture within a sustainability framework. This study evaluates the agronomic, biological, and economic impacts of biochars produced from three agri-food residues: vinasses, olive pomace, and tomato peels. Methods: Biochars were applied to tomato ( Solanum lycopersicum cv Heinz 1301) and wheat ( Triticum durum cv Svevo) in a greenhouse experiment at concentrations of 0.1-0.25-0.5% w/w, to assess their effects on plant biomass, physiology and gene expression, total countable microorganisms, enzymes involved in nitrogen mineralization (arylamidase), cellulose degradation (β-glucosidase) and phosphorus release (phosphatases). Economic and environmental assessments were also carried out. Results and discussion: Vinasse biochar contained the highest levels of nitrogen (12000 mg/kg), potassium (11700 mg/kg), and phosphorus (4200 mg/kg), performing comparably to vinasse-based compost. A concentration of 0.5% biochar derived from vinasses increased canopy cover in tomato (+125%), and stem length (+13%), fresh and dry root weight (+97% and 57%, respectively), and stem weight (+41% and 44%, respectively) in wheat. The same biochar modulated genes involved in plant growth and development, cell wall biogenesis, nutrient transport, hormone signaling, and stress response in both plants. All biochars, particularly those derived from vinasses, enhanced arylamidase activity in tomato plants compared with the control. The same biochar enhanced activity of β-glucosidase when added at 0.5% in wheat (+ 29%) and tomato (+20%) over the control. Biochar derived from tomato peels at 0.5% enhanced the phosphatase activity (+27%) in tomato plants, while biochar derived from olive at 0.5% enhanced the same activity (+45%) in wheat. Economic and environmental evaluations revealed that these biochars were better than composts derived from the same residues, in terms of sustainability and economic value.

Quantum dots such as CdS QDs have been extensively studied using human cells, plants, and unicellular eukaryotes such as Saccharomyces cerevisiae, whereas ZnS QDs—considered low-toxicity alternatives to cadmium-based nanomaterials—remain comparatively underexplored. Following preliminary analyses of ZnS QDs’ effects on wild-type S. cerevisiae BY4742 growth, the Yeast Knock-Out collection, comprising ~4600 haploid mutants deleted in non-essential genes, was screened in the presence of ZnS QDs. Sensitive mutants were predominantly associated with mitochondrial functions, prompting further characterization of sod1Δ, glr1Δ, and of the hypersensitive mutant pos5Δ. This last mutant, which lacks a mitochondrial NADH kinase, showed hypersensitivity specific to ZnS QDs but not to CdS QDs or zinc sulfate (ZnSO₄). Flow cytometry analysis of the wild-type strain and the pos5Δ mutant detected no significant increase in reactive oxygen species after ZnS QD treatment. RNA-sequencing analyses of the wild-type strain and the pos5Δ mutant exposed to ZnS QDs (or ZnSO₄) revealed that ZnS QD exposure selectively modulated genes encoding mitochondrial proteins, metal-binding factors, and intracellular trafficking components. Comparison with published data on CdS QDs identified specific mechanisms involving protein synthesis and degradation. Saccharomyces cerevisiae once again proved its versatility for studying engineered nanomaterial interactions with biological systems.

The pathological aggregation of α-synuclein (syn) is a hallmark of Parkinson’s disease (PD) and related synucleinopathies. In the present study, we report a supramolecular strategy to reduce syn aggregation and its associated cellular toxicity using a panel of rationally designed anionic calix[4]­arenes. Among them, CLXP1, a tetraphosphonato derivative with a rigid, preorganized cavity, emerged as a potent inhibitor of syn aggregation in a validated yeast model of PD based on syn overexpression. CLXP1 significantly improved cell viability by reducing the formation of toxic intracellular inclusions of syn and restoring multiple dysregulated molecular pathways while preserving mitochondrial morphology and redox and lipid homeostasis and enhancing autophagic clearance. NMR analyses revealed that CLXP1 interacts with key residues of the N-terminal domain of syn, critically involved in membrane anchoring and oligomerization, supporting a model in which this interaction stabilizes the α-helical, membrane-bound conformation of syn, thereby preventing its progression toward toxic oligomeric species. These findings highlight the potential of supramolecular host–guest chemistry to selectively target intrinsically disordered proteins and provide a promising scaffold for the development of new modulators of protein aggregation.

Currently, there is growing interest in wheat-based products with a reduced digestive impact. We investigated whether agronomic management could modulate the accumulation of immunogenic peptides in durum wheat by using two multifactorial field trials. In the first trial, immunogenic peptide levels were influenced by genotype and by its interaction with nitrogen supply and sowing density, indicating that management effects are highly genotype dependent. In the second trial, the sowing date and fertilization regime affected immunogenic peptide accumulation, with the sowing date being the main driver. Spring sowing reduced the grain yield and increased grain protein and immunogenic peptide levels compared with fall sowing. Overall, these results support the adoption of genotype-specific management strategies to reduce immunogenic peptide accumulation while maintaining a yield in durum wheat.

Sustainable food production systems based on the use of biofertilizers and soil improvers are proposed to mitigate agricultural-related environmental impacts and address the climate crisis. In particular, plant growth-promoting microbes (PGPM) and biochar (Char) have been reported to improve plant growth, soil quality, and crop yield; however, their effects on food quality remain debated. In this study, untargeted metabolomics based on ultra-high performance liquid chromatography–ion mobility–high-resolution mass spectrometry (UHPLC-IMS-HRMS) and proton nuclear magnetic resonance spectroscopy (¹H-NMR) are proposed to achieve a comprehensive investigation of the effects of Char, PGPM and Char+PGPM on durum wheat. A total of 88 metabolites were annotated by UHPLC-IMS-HRMS, mainly belonging to carbohydrates, flavones, flavonoids, glycerophospholipids, and glycolipids, while 30 compounds were annotated by ¹H-NMR, mostly amino acids and short-chain carboxylic acids. The two datasets were merged with the gluten protein content dataset by using low- and mid-level data fusion approaches, obtaining models that exhibit excellent classification performance. Integrated analysis highlighted that the combined Char+PGPM treatment induced metabolic changes across multiple chemical classes, including enrichment of flavonoids and lipids, and downregulation of carbohydrate metabolites, suggesting a redistribution of carbon resources and modulation of secondary metabolism with potential implications on wheat grain quality.

The circular bioeconomy, centred on the principles of “Reduce, Reuse, and Recycle”, is central to achieving the goals of the European Green Deal and the “Farm to Fork” strategy. The key approach, within this framework, is the valorisation of food processing side-streams through various processing technologies to produce fertilisers that, when applied to the soil, act as potential “soil improvers”. When applied to soil, these materials affect not only the physical, chemical, and biological properties of soil but also impact greenhouse gas emissions, nutrient leaching, and the levels of contaminants or pathogens. A systematic review of field studies conducted in European soils between 2014 and 2024 was performed with stringent inclusion and exclusion criteria, which allowed the identification of suitable articles in three independent steps. The main soil improvers derived from various agri-food side-streams were biochar, compost, and digestate. Their effects, along with the potential risks associated with their use in agricultural fields, were carefully evaluated and discussed. This review forms part of the DeliSoil project “Delivering safe, sustainable, tailored & societally accepted soil improvers from circular food production for boosting soil health” funded under the European Union “A Soil Deal for Europe”. This systematic review showed that soil improvers enhance soil health by improving microbial diversity, organic matter, and water retention, and by boosting plant growth. However, potential risks require careful management, and long-term studies are needed to fully assess their environmental and agronomic impacts. Graphical Abstract

Soil health is crucial for the sustainability of agricultural practices and ecosystem resilience. Using a data mining approach, this study aims to explore emerging themes related to the impact of soil improvers on soil health by analyzing results from various EU-funded agricultural projects, with the final goal of identifying the key factors driving the effectiveness of soil amendments. By integrating data mining and text analysis, the study extracts, aggregates, and visualizes insights, providing a comprehensive overview of innovative strategies to enhance soil fertility and promote ecological balance. This integrated analytical framework offers a nuanced understanding of the conceptual landscape surrounding soil health in EU projects, highlighting the multifaceted roles of organic amendments and microbial solutions. Our findings underscore the critical link between organic amendments and soil health, highlighting their potential as strategic tools for achieving more sustainable agricultural systems. These findings provide a basis for refining soil management strategies in agriculture and support the development of evidence-based policies aimed at improving soil health and fostering ecological balance across Europe.

The study investigates the iron oxide nanoparticles (nFe₃O₄) nanobiotransformation dynamics and impact at physical and molecular level.

Conventional agriculture is mainly dependent on chemistry and energy to promote growth and yield and on pesticides to protect crops from pests or pathogens. Biofertilizers as plant growth‐promoting microbes (PGPM) and novel soil amendments, as biochar, are considered sustainable alternatives to diminish the excessive use of chemicals in agriculture. The effects of biochar, whether used alone or in combination with biofertilizers, are still not fully understood, and its potential benefits have yet to be thoroughly investigated. Additional field studies across various agronomic conditions are needed to confirm the impact of biochar–microbial consortia before they can be widely adopted in sustainable agricultural practices. Industrial tomato is a paradigmatic example of a culture requiring resources as well as fertilisers and energy. Results from field trials performed in two different locations in Emilia‐Romagna (Italy): Parma and Ferrara (two different fields), with both conventional and organic practices, are here reported. Biochar, PGPM and arbuscular mycorrhizal fungi (AMF) were applied in field trials for two to three consecutive years. Soil characteristics, both chemical and biological, revealed that the fields had features comparable to the average European arable soils; specifically, the rhizospheric biological diversity indexes were similar in the three locations. The most interesting results were obtained in the Parma field location, where it was observed that biochar and PGPM treatment determined a reduction in the number of not ripe fruits (average 65%). When biochar was combined with newly developed PGPM in the two conventional fields, the value of commercial production and the Brix index of the harvest increased. The biofertilizers, when combined with biochar, remarkably permitted saving 20% of chemical fertilisers with a consequent saving in greenhouse gas (GHG) emissions. These results were also considered from an economic perspective, which revealed that PGPM and biochar increase the gross margins while reducing the environmental impact of the tomato cultivation.