Bioconversion of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) confers advantages of mild conditions, high selectivity, and eco-friendliness. However, enzymatic catalysis is expensive and multi-strain microbial catalysis is limited by the transmembrane transport of intermediates between strains, restricting the efficient synthesis of FDCA and generating a byproduct. In this study, we aimed to establish sequential regulation of dual catalytic modules in Escherichia coli to precisely control the expression of hydroxymethylfurfural oxidase (HMFO) and vanillin dehydrogenase (VDH1), enabling the directed one-pot conversion of HMF to FDCA with no detectable accumulation of the measured intermediates and simplifying the operational process. At a 15 mM HMF scale, this strategy achieved a FDCA yield of 100
Access to modern electricity and clean cooking technologies remains uneven across much of Africa, despite the continent’s abundant biomass resources, which have the potential to enhance energy security while supporting the transition toward a circular bioeconomy. However, a substantial proportion of agricultural, forestry, municipal, and marine organic residues is still treated as waste rather than valorized within the formal energy sector. Morocco exemplifies this disconnect. Although the country has achieved near-universal rural electrification, biomass derived from agricultural and marine resources contributes less than 2
The medicinal fruiting bodies of Shiraia harbor diverse microbial communities that are increasingly recognized as important regulators of fungal secondary metabolism. While endophytic bacteria and fungi associated with Shiraia have recently attracted considerable attention, the diversity and functional roles of endophytic actinomycetes remain largely unexplored. Here, we combined culture-dependent isolation with high-throughput 16 S rRNA amplicon sequencing to investigate the endophytic actinomycete community associated with Shiraia fruiting bodies. A total of 28 actinomycete isolates representing four genera were recovered, with Streptomyces being the predominant culturable genus. Functional screening identified the native endophyte S. pseudogriseolus A6 as the most effective elicitor of fungal hypocrellin A (HA) biosynthesis. Genome analysis revealed abundant carbohydrate-active enzymes and 27 secondary metabolite biosynthetic gene clusters, indicating a strong genetic potential for fungal colonization and metabolite-mediated communication. Co-cultivation with live strain A6 markedly enhanced both intracellular and extracellular HA accumulation without significantly affecting fungal biomass. Under the optimized co-cultivation conditions, total HA production reached 296.0 mg/L, representing a threefold increase over the monoculture control. Furthermore, A6 coordinately upregulated the expression of HA biosynthetic genes and metabolite transport genes. This study provides the first characterization of endophytic actinomycetes associated with Shiraia fruiting bodies and identifies actinomycete elicitors capable of stimulating fungal HA biosynthesis. These findings expand current knowledge of the Shiraia microbiome and highlight endophytic actinomycetes as promising microbial resources for enhancing fungal perylenequinone production.
Laccases are copper-containing oxidases that have been widely investigated for the decolorization and degradation of synthetic dyes, including azo, anthraquinone, triphenylmethane, indigo and thiazine dyes. However, their application in dye-containing wastewater remains constrained by enzyme instability under complex effluent conditions, limited oxidation of some recalcitrant or high-redox-potential dyes, mediator dependence, and poor recovery and reuse of free laccase. This review discusses recent progress in laccase-catalyzed dye degradation from a mechanism-to-engineering perspective, linking dye-structure-dependent degradation pathways with laccase discovery, recombinant expression, protein engineering and immobilization strategies. Particular attention is given to comparative evidence across dye classes, fungal and bacterial laccases, engineered variants generated through rational design, directed evolution and semi-rational mutagenesis, and immobilized laccase systems based on nanomaterials, biopolymers, magnetic carriers and porous supports. In addition, the review distinguishes laboratory model dye systems from simulated and real wastewater applications, highlighting the need for more cautious interpretation of decolorization efficiency, degradation evidence and process feasibility. Finally, we outline future prospects for laccase applications in dye degradation, including the mining of novel laccases from extreme environments, artificial intelligence-assisted laccase design, and developing new nano-scale carrier materials, which will be essential for enhancing laccase performance and broadening its application scope.
Fruit and vegetable (FV) waste represents an underutilized organic stream in Europe, yet its soluble sugar fraction remains poorly exploited as a bioprocess feedstock. Recombinant enzyme production from biowaste is often bottlenecked by heterogeneous substrate composition, low fermentable sugar titres, and uncertain process economics. This study evaluates the techno-economic feasibility of recombinant Candida rugosa lipase type 1 (CRL1) production in Pichia pastoris (Komagataella phaffii) under the constitutive glyceraldehyde-3-phosphate dehydrogenase promoter pGAP across three carbon sources: commercial glucose (Scenario A), mechanically pressed fruit and vegetable juice (Scenario B), and an enzymatically hydrolysed, nanofiltered fruit and vegetablesugar stream (Scenario C). Bench-scale fermentation kinetics were integrated into 24 SuperPro Designer models across four scales (1 to 5000 L nominal vessel capacity; 0.75 to 3750 L working volume) under batch and continuous chemostat ( D=0.05 h^-1 ) modes. Interpreted through the Titre, Rate, and Yield (TRY) framework, continuous operation on glucose increased volumetric CRL1 productivity 12.6-fold over batch (0.084 vs. 0.06 U L−1 h−1. Conversely, continuous operation on the hydrolysed stream did not improve productivity over batch, indicating potential kinetic inhibition from enzymatic pretreatment products or suboptimal dilution rate. At the 5000 L vessel scale under continuous mode, unit production costs were 1186,36,049, and 3416kg^-1for Scenarios A, B, and C, respectively, all exceeding the commodity lipase benchmark (25 kg^-1 ). Facility-dependent costs dominated Scenarios A and B (73
