Microbial fuel cells (MFCs) directly convert chemical energy into electrical energy via the microbial catalytic oxidation of organic substrates, demonstrating immense potential for simultaneous pollutant degradation and bioenergy recovery. However, their industrialization has long been hindered by bottlenecks like low electron transfer and energy conversion efficiencies, high material costs, and poor large-scale stability. Iron-sulfur minerals, possessing unique electron transfer properties and environmental compatibility, provide an effective solution for the sustainable development of MFCs. Nevertheless, current literature predominantly focuses on their abiotic catalytic oxidation processes, lacking a systematic review of their applications in MFCs. This partially neglects the complex interactions among intrinsic mineral properties, environmental factors, and interfacial microbial dynamics, limiting an in-depth understanding of system efficacy and engineering bottlenecks. Therefore, this paper systematically reviews the research progress on the applications of iron-sulfur minerals in MFCs, elucidating their core mechanisms of action under diverse application forms. Furthermore, it summarizes key factors influencing the power generation performance and pollutant removal efficiency of the system. Finally, this review analyzes the engineering challenges and proposes future research directions, aiming to provide a fundamental reference for promoting both the technical optimization and practical application of iron-sulfur mineral-based MFCs.

Current research on antibiotic resistance genes (ARGs) removal during manure composting has primarily focused on differences across animal species. However, how farming practices, which fundamentally differ in feed composition, antibiotic use, and rearing density, shape ARGs removal patterns and underlying mechanisms remains poorly understood. Here we compared manure composting between large-scale (LS) and free-range (FR) systems and revealed fundamentally divergent causal pathways governing ARGs dynamics. LS achieved higher removal rates of total ARGs (93% vs 57%) and total mobile genetic elements (MGEs; 93% vs 77%) than FR, operating through a biotic-driven mechanism: composting conditions suppressed specialized bacterial consortia that served as primary ARGs hosts, with biotic factors exerting a dominant effect on ARGs variation (path coefficient: r = 0.92). In contrast, FR relied on an abiotic-factor-dominated dual-suppression mechanism, with the abiotic latent variable exerting a dominant negative effect on ARGs abundance (r = -0.59), while biotic contributions were minimal (r = 0.26). Driven by their distinct feed origins, key nutritional components diverged significantly between systems: nitrogen-related factors [total nitrogen (TN) + protein (P)] dominated ARGs variation in LS (56.86%), whereas TS was the predominant driver in FR (76.06%). FR also exhibited greater microbial richness and a wider variety of genera, but lacked specialized ARG-hosting consortia, explaining its lower removal efficiency. Collectively, our findings reveal system-associated differences in the mechanistic pathways of ARGs removal between the two farming systems, underscoring the potential necessity for system-specific composting strategies.

Medium chain-methyl ketones are molecules with high energy content and various industrial applications. So far, biotechnological methyl ketone production was performed with glucose as a carbon source in minimal media, which is often not the best choice in terms of achieving a sustainable and cost-efficient bioprocess. We evaluated the application of lignocellulosic hydrolysates as a carbon source derived from agricultural waste streams that do not compete with food production. Notably, we demonstrate that methyl ketone production is feasible from both the cellulosic and hemicellulosic fractions. In bioreactor cultivations, the product yield with the cellulosic hydrolysate exceeded the yield obtained from glucose minimal media by more than 10%. These results indicate that the use of alternative carbon sources for methyl ketone production is promising to establish an economic and ecologic bioprocess.

During saccharification and fermentation, glucose feedback inhibition severely restricts enzymatic hydrolysis efficiency. To address this issue, an integrated Mild Pretreatment-Pre-Enzymatic Hydrolysis-High-Solid Synchronized State Fermentation (MP-PEH-HSSF) process was developed using corn stover (CS) for efficient lactic acid production. In the mild pretreatment (MP) stage, treatment with low-dosage sodium hydroxide (0.02 g g⁻¹ CS) and 5% (w/w) aqueous ammonia at 50% solid loading achieved 43.01% lignin removal while reducing chemical consumption. In the pre-enzymatic hydrolysis (PEH) stage, optimized enzymatic conditions and a staged enzyme addition strategy (PEH:EH = 3:7) effectively alleviated product inhibition, increasing cellulose and hemicellulose conversion rates to 45.72% and 30.01%, respectively. In the high-solid synchronized saccharification and fermentation (HSSF) stage, at a solid loading of 30% (w/w), PEH markedly enhanced the release of fermentable sugars, with a peak glucose concentration of 36.86 g L⁻¹. Among six screened L-lactic bacteria, Lacticaseibacillus rhamnosus exhibited the best performance, achieving a L-L-lactic titer of 49.57 g L-1 with an optical purity of 97.12%, and a yield of 0.165 g g-1 of pretreated CS. In addition, the xylose recovery from fermentation residues reached 83.27%, enabling efficient cascade utilization of carbon sources. Overall, the proposed MP-PEH-HSSF integrated strategy effectively mitigates glucose feedback inhibition, enhances the overall conversion efficiency of CS, and improves L-lactic production, providing a feasible pathway for the high-value utilization of lignocellulosic biomass.

Due to the ability to catalyze the formation of covalent cross-links between proteins, microbial transglutaminase (MTGase) has been widely applied in the fields of food industry, biomedicine and biotechnology. However, the industrial-scale purification of MTGase is often limited by the complexity and low efficiency of traditional chromatographic techniques. Herein, we introduce an economical and handy method utilizing a recyclable thermoseparating ethylene oxide-propylene oxide (EOPO) random copolymer (EO20PO80) for the direct and efficient precipitation of MTGase from fermentation broth. Through systematic optimization of copolymer concentration, pH, ionic strength and subsequent wash step with ethanol, we obtained MTGase powder after freeze drying with high product yield and enzyme activity. The purity of was detected through SDS-PAGE and the specific activity increased by 63 times compared with the of MTGase in fermentation broth. The MTGase purified by this process had an enzyme activity up to 46411.88 U/g with the enzyme activity recovery rate reaching up to 99% while over 98% of precipitant EO20PO80 can be recovered through only temperature adjustment. The molecular dynamic simulation was adopted to visualize the process of MTGase precipitation and interaction between MTGase and EOPO. The work establishes a simple, scalable, and efficient purification strategy for MTGase, highlighting the potential of smart copolymers as versatile tools for downstream processing in industrial enzyme production.

Lignocellulosic hydrolysates contain inhibitors that hinder lactic acid (LA) production. This study evaluated a synthetic microbial community (SMC) of five lactic acid bacteria for fermenting undetoxified corn stover hydrolysate. Metatranscriptome analysis revealed links between fermentation performance and inhibitor effects. Although LA yield decreased by 5.79% versus the control, SMC achieved 94.47% mixed sugar utilization and produced L-LA with 99.70% optical purity. Transcriptomic data suggest that hydrolysate inhibitors may suppress glycolysis and the pentose phosphate pathway, which may contribute to a shift in carbon flux to the TCA cycle. Upregulation of malolactic enzyme (mleA) and downregulation of D-lactate dehydrogenase/hydroxyacylglutathione hydrolase (ldhA/gloB) correlated with enhanced L-LA purity. Syringaldehyde showed the strongest inhibition among tested compounds. These findings demonstrate an effective SMC-based strategy for producing high-purity L-LA from undetoxified hydrolysates, advancing biomass utilization.

Borophene was grown on glass coverslip substrates by chemical vapor deposition (CVD) to investigate its effects on fibroblast viability and selected oxidative stress, apoptosis-related, and inflammatory markers. The deposited films were characterized using optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy, X-ray diffraction, and atomic force microscopy. Surface imaging revealed film coverage across the examined regions, and atomic force microscopy indicated a representative thickness of approximately 27nm. L929 fibroblasts were cultured on borophene-coated glass coverslips, and cellular responses were evaluated after 24h using the MTT assay, total antioxidant capacity (TAC), total oxidant status (TOS), and measurements of BAX, BCL-2, IL-1, and IL-10. Cell viability was 90.84% relative to the control, with no statistically significant difference reported. TAC, TOS, and BAX also showed no statistically significant changes. In contrast, BCL-2 levels increased significantly (P < 0.001), suggesting a potential adaptive or anti-apoptotic response. These findings provide preliminary evidence of limited short-term cytotoxicity under the tested conditions. However, the increased BCL-2 level alone does not establish functional cytoprotection, and further studies are needed to clarify the underlying mechanisms and longer-term biological effects.

The valorization of side streams from industrial production is one of the key strategies to achieve more environmentally and economically sustainable manufacturing processes. Biodiesel biorefineries generate significant amounts of crude glycerol, which has potential for conversion into higher-value products. Instead of an expensive multistep purification procedure for the production of high-grade glycerol, there are many possible ways to utilize crude or partially purified glycerol directly by chemical or microbial conversions to produce valuable compounds. One approach is the use of enzymes, which often can be used directly in the biorefineries (e.g., lipases for transesterification). The use of microorganisms can be limited by the presence of impurities in crude glycerol, which may inhibit their growth and reduce product yields. While naturally robust strains are often required to withstand these conditions, recombinant DNA technology expands the utility of this substrate by engineering these microorganisms to produce specific, high-value compounds. This review provides a comprehensive overview of the microbial conversion of waste glycerol using recombinant and genetically modified strains, with particular emphasis on their potential for application in industry.

Efficient production of enantiopure phenylserine (PhSer) is hampered by poor economy and challenging byproduct separation in conventional resolution methods. Phenylserine dehydratase (PSDH) offers an alternative by catalyzing irreversible dehydration, yet its strict stereospecificity toward the l-threo isomer limits its synthetic scope. Herein, structure-guided site-saturation mutagenesis of l-PSDH from Paraburkholderia xenovorans yielded the G93C mutant, which acquired activity against the previously inaccessible d-erythro isomer. Both wild-type and G93C enabled preparative-scale kinetic resolution, affording enantiopure l-threo- and d-erythro-PhSer with improved isolated yields of 43.6% and 43.0%, respectively. To upgrade the byproduct, a multi-enzyme cascade combining PSDHs, d-lactate dehydrogenase, and formate dehydrogenase was constructed, which simultaneously resolved racemic PhSer and converted the phenylpyruvate byproduct in situ into high-value d-phenyllactic acid. This work expands the synthetic utility of PSDHs through stereoselectivity engineering and cascade design, establishing an efficient biocatalytic platform for co-producing enantiopure PhSer and d-phenyllactic acid.

High-fidelity PCR amplification of long or challenging DNA templates typically relies on expensive commercial kits and lengthy amplification protocols. Here, we have developed a high-performance, cost-effective PCR system that can be readily prepared in-house. The system is based on a Pfu-sso7d fusion DNA polymerase, which combines the high fidelity of Pfu DNA polymerase with the enhanced processivity conferred by the sso7d DNA-binding domain. When supplemented with a combined enhancer cocktail comprising TneSSB and dUTPase, the system exhibited substantial improvements in amplification yield, speed, and robustness. The optimized formulation consistently amplified DNA fragments up to 15kb and increased the yield of 10kb amplicons by approximately fourfold. The enhancer cocktail also markedly reduced amplification time, enabling the amplification of a 1kb fragment in 25min (vs. 45min), a 5kb fragment in 45min (vs. 4h), and a 10kb fragment in approximately 3h (vs. 6h). Furthermore, the system demonstrated enhanced tolerance to common PCR inhibitors present in DNA extraction samples and clinical specimens, supporting successful amplification in the presence of up to 5% whole human blood or 20% human serum.

Terpenic esters are compounds of considerable industrial relevance that can be obtained through direct extraction or chemical synthesis. However, these conventional approaches present limitations, making biotechnological production a promising and sustainable alternative. In this study, it was investigated the biosynthesis of citronellyl pentanoate using lipase B from Candida antarctica (CALB) and lipase from Rhizomucor miehei (RML), either in soluble form or immobilized on magnetic cashew apple bagasse (CAB) lignin. After immobilization, the enzymes exhibited satisfactory activity (12.6 ± 0.7 U.g[-1] for CALB; 13.1 ± 0.1 U.g[-1] for RML) and high immobilization yields (71.5 ± 1.2% for CALB; and 79.9 ± 4.6% for RML). Biotransformation assays revealed that the optimal reaction conditions were 50 °C and a 1:1 alcohol-to-acid molar ratio, achieving conversion of citronellol above 90% within 24h for immobilized lipases. The operational stability of the biocatalyst was evaluated over 10 reaction cycles of 24h, verifying that the catalytic activity was maintained, with conversions above 80% at the last cycle. The citronellyl pentanoate attained chromatographic purity of 97.3% and its antimicrobial activity was evaluated. Against Staphylococcus aureus, inhibition zones were 15mm for the ester and 19.5mm for the citronellol, while against Escherichia coli they were 18.5mm and 20mm, respectively. The citronellyl pentanoate showed greater antifungal activity against Fusarium graminearum DSM 4528 than the precursor alcohol (IC50 reduced by ~68%), while it presented less antibacterial activity effectiveness against Pseudomonas syringae pv. tomato DC3000. These results highlight the selective bioactivity of terpenic esters and their potential as targeted antifungal agents. Overall, the synthesis of citronellyl pentanoate proved efficient, achieving high yields with promising biotechnological potential.

Hyaluronic acid (HA) in the tumor microenvironment forms a physical barrier that hinders the penetration of chemotherapeutic drugs. Hylp1 is a bacteriophage-encoded hyaluronate lyase with a unique triple-stranded β-helix structure harboring three active centers. In this study, we recombinantly expressed Hylp1 in Escherichia coli and developed a purification scheme that yielded high-purity and high-activity enzyme. Enzymatic characterization showed that recombinant Hylp1 retained substantial activity at 37 °C, degraded HA via an endolytic β‑elimination mechanism, and exhibited higher catalytic activity than recombinant human hyaluronidase PH20 (rHuPH20). In A549 lung cancer cells, Hylp1 alone showed no direct cytotoxicity. However, when combined with gemcitabine and cisplatin, Hylp1 synergistically inhibited cell proliferation, migration, and invasion. Using 3D tumor spheroids, we demonstrate that Hylp1 promotes diffusion of small-molecule drugs into the spheroid interior by degrading HA in the extracellular matrix, thereby increasing chemotherapeutic cytotoxicity. These findings establish Hylp1 as an adjuvant that improves chemotherapy efficacy in HA‑rich solid tumors.

Dilute acid- and ammonia-assisted steam explosion (SE) are promising pretreatments for lignocellulosic biorefineries and induce distinct structural changes in biomass. Here, sulfuric acid-, phosphoric acid-, and ammonia-assisted SE were comparatively investigated within a wash-free framework to elucidate additive-dependent mechanisms linking biomass structural reconstruction to downstream bioconversion. Mechanistic analyses revealed that sulfuric acid-assisted SE intensified lignin-related inhibition, resulting in the highest surface lignin coverage (SLC) and the strongest non-productive cellulase adsorption. By contrast, phosphoric acid-assisted SE preferentially promoted hemicellulose removal while alleviating lignin condensation, yielding the lowest SLC. Ammonia-assisted SE suppressed lignin condensation despite limited lignin removal; however, its higher water retention capacity impaired enzymatic hydrolysis under high-solids conditions. Notably, SLC showed the strongest correlation with glucose yield (R[2] = 0.999), highlighting it as an integrated indicator of enzymatic hydrolysis performance. Consistent with these structural differences, the sulfuric acid-, phosphoric acid-, and ammonia-assisted corn stover achieved glucose yields of 85.72%, 93.28%, and 92.16%, respectively. Moreover, retained soluble components in the wash-free system appeared to benefit downstream fermentation, as all hydrolysates remained fermentable without detoxification, with the ammonia-assisted SE hydrolysate showing the best co-production of yeast protein and ethanol. These findings provide mechanistic guidance for additive selection in water-efficient lignocellulosic biorefineries.

Lignin is largely wasted agro-industrial aromatic biomass. Green deep eutectic solvents (DES) fractionation optimizes its UV-blocking, antioxidant and antibacterial performance, outperforming traditional alkali extraction. This study compares NaOH and four choline chloride acidic DES to reveal their regulation effects on rice straw lignin structure and functionalities. The recovered lignin fractions were characterized by elemental analysis (EA), FTIR, UV-Vis spectroscopy, and gel permeation chromatography (GPC) to evaluate their elemental composition, chemical structure, molecular weight distribution, UV-shielding capacity, antioxidant activity, and antibacterial properties. Both alkaline and DES pretreatments effectively fractionated lignin from rice straw, yielding high-purity lignin fractions with well-preserved aromatic structures, low molecular weights, and narrow polydispersity. Compared with alkaline-extracted lignin, DES-derived lignin showed increased UV-shielding performance and a higher phenolic hydroxyl group content. These characteristics were associated with enhanced DPPH• radical scavenging activity, hydroxyl radical scavenging activity, and ferric ion reducing power. DES-derived lignin also displayed broad-spectrum antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Salmonella, and E. coli. Pearson correlation analysis revealed a structure-activity relationship in which reduced molecular weight was associated with increased phenolic hydroxyl content, leading to improved antioxidant capacity and antibacterial activity. These results provide a foundation for the use of DES-derived rice straw lignin in biodegradable biomaterials, natural antioxidant formulations, and bio-based antibacterial agents.