NODES - SPOKE 6 Project FORMIDABILÆ - D3.2 Feed conservation and quality, safety of diets and circularity

These studies integrate metabolomic, metagenomic, and mycotoxin screening approaches to investigate the impact of diet on milk composition and safety. Metabolomic analysis is complemented by metagenomic profiling to explore associations between discriminating milk metabolites and microbial communities influenced by different feeding strategies. The dataset is further enriched with targeted analysis of amino acids (both essential and non-essential), B vitamins, and phenolic compounds linked to dietary inputs. Additionally, a multiscreening method for mycotoxins is applied to various biofluids, including milk, to assess potential carryover phenomena, with a particular focus on aflatoxins and emerging mycotoxins. This integrated approach aims to provide a comprehensive understanding of how diet affects milk quality, microbial ecology, and food safety risks. Another this study describes the development of a low-cost, bioprinted acetate biosensor composed of engineered E. coli embedded in a hydrogel. The bacteria carry a synthetic DNA circuit that produces red fluorescence in response to acetate. After selecting and characterizing the glnAP2 sensor system, researchers optimized the abiotic matrix to ensure structural integrity and minimal background activity. Detection protocols were established using both direct sample application and volatile sensing. The biosensor successfully detected acetate concentrations above 300 mg/L in silage samples, with fluorescence output correlating well with HPLC measurements (r = 0.78). While less sensitive than advanced analytical methods, the biosensor offers a simple, automatable, and cost-effective tool for monitoring acetate accumulation in fermentation processes. This document is a deliverable of the project FORMIDABILÆ ("Forage system to make resilient Maize, Dairy and Biogas supply chains for a Lasting Agricultural Ecosystem"), which promotes approaches aimed at improving the smart, resilient, circular and diversified farm to ensure food security and social economic sustainability of dairy food chains with the aim of reducing greenhouse gas emissions in this sector. This document is part of the project NODES which has received funding from the MUR – Missione 4, Componente 2, Investimento 1.5 – Creazione e rafforzamento di “Ecosistemi dell’innovazione”, costruzione di “leader territoriali di R&S'' – del PNRR funded by the European Union - NextGenerationEU with grant agreement no. ECS00000036