Developent of microbiome-based bioprocesses for sustainable production of bio-resources for the textile industry

Pigmented microorganisms from under explored environments where explored as a possible sources of bioactive natural compounds for textile colouring. A targeted isolation strategy was employed which yielded multiple pigmented strains; seven candidates were then selected for in-depth study based on pigmentation, growth and scalability, combining fermentation, extraction, solvent partitioning, UPLC–MS profiling, whole-genome sequencing with BGC mining, and finally functional screening for total antioxidant capacity, antimicrobial activity and antibiofilm activity were also performed. Metabolomics analysis through UPLC-MS managed to detected anthraquinone signals and diverse carotenoid signatures across the prepared extracts, with the concentrations of detected anthraquinones falling into the ng/ml range making them currently not economically exploitable without process intensification. Genome mining revealed numerous terpene, PKS and NRPS-like clusters in various isolates, but canonical AQ biosynthetic loci were not identified. Functionally, four extracts exhibited measurable antioxidant capacity (TAC). Antimicrobial results varied between assays: with several strains showed activity in plate assays but weaker or variable effects in broth, which might reflect an incomplete extraction of antimicrobial molecules. Lastly, water-soluble extracts from P. marcusii and Cladosporium reduced the production of biofilm by Pseudomonas aeruginosa, indicating secreted polar antibiofilm agents. Overall this work showcase a pipeline for the characterization of pigmented extracts, which might lead to the bio discovery of functional bioactive compounds, while the production of anthraquinones for textile applications still remains limited, and necessitates more studies to increase production yields.