Bioresource Technology最新文献

This study surveyed the fates of artificial sweeteners in influent, effluent, and sewage sludge (SS) in wastewater treatment plant, and investigated the effects of Micro-Kaolin (Micro-KL) and Nano-Kaolin (Nano-KL) on nitrogen transformation and sucralose (SUC) and acesulfame (ACE) degradation during SS composting. Results showed the cumulative rate of ACE and SUC in SS was ∼76 %. During SS composting, kaolin reduced NH₃ emissions by 30.2–45.38 %, and N₂O emissions by 38.4–38.9 %, while the Micro-KL and Nano-KL reduced nitrogen losses by 14.8 % and 12.5 %, respectively. Meanwhile, Micro-KL and Nano-KL increased ACE degradation by 76.8 % and 84.2 %, and SUC degradation by 75.3 % and 77.7 %, and significantly shifted microbial community structure. Furthermore, kaolin caused a positive association between Actinobacteria and sweetener degradation. Taken together, kaolin effectively inhibited nitrogen loss and promoted the degradation of ACE and SUC during the SS composting, which is of great significance for the removal of emerging organic pollutants in SS.

The nitrogen loss in composting is primarily driven by the transformation of organic nitrogen, yet the mechanisms underlying the degradation process remain incompletely understood. This study employed protein family domains (Pfams) analysis based on metagenomic sequencing to investigate the functional characteristics, key microorganisms, and environmental parameters influencing organic nitrogen degradation in chicken manure and pig manure composting. 154 Pfams associated with ammonification function were identified. Predominant Pfams: proteolytic peptidase, followed by chitin/cell wall degraders, least involved in nucleic acid degradation. Ammonifying microbial diversity was basically consistent among compost types, particularly in the thermophilic stage with the peak of abundance of dominant ammonifying microorganisms. Viruses played an important role in ammonification process, especially Uroviricota. 26 key ammonifying genera were identified by the microbial network. pH dominated the metabolic activity of ammonifying microorganisms in various manure compost types, primarily consisting of protein-degrading bacteria with stable community structures.

Indigenous microalgae-bacteria consortium (IMBC) offers significant advantages for swine wastewater (SW) treatment including enhanced adaptability and resource recovery. In this review, the approaches for enriching IMBC both in situ and ex situ were comprehensively described, followed by symbiotic mechanisms for IMBC which involve metabolic cross-feeding and signal transmission. Strategies for enhancing treatment efficiencies of SW-originated IMBC were then introduced, including improving SW quality, optimizing system operating conditions, and adjusting microbial activities. Recommendations for maximizing treatment efficiencies were particularly proposed using a decision tree approach. Moreover, removal/recovery mechanisms for typical pollutants in SW using IMBC were critically discussed. Ultimately, a technical route termed SW-IMBC-Crop-Pig was proposed, to achieve a closed-loop economy for pig farms by integrating SW treatment with crop cultivation. This review provides a deeper understanding of the mechanism and strategies for IMBC’s resource recovery from SW.

Strengthening the direct interspecies electron transfer (DIET) is an effective strategy to improve the performance of anaerobic digestion (AD) process. In this study, the polyaniline functionated activated carbon (AC-PANi) was prepared by chemical oxidative polymerization. This material possessed pseudo-capacitance properties as well as excellent charge transfer capability. The experimental results demonstrated that the incorporation of AC-PANi in AD process could efficiently increase the chemical oxygen demand (COD) removal (18.6 %) and daily methane production rate (35.3 %). The AC-PANi can also act as an extracellular acceptor to promote the synthesis of adenosine triphosphate (ATP) and secretion of extracellular enzymes as well as cytochrome C (Cyt-C). The content of coenzyme F₄₂₀ on methanogens was also shown to be increased by 60.9 % with the addition of AC-PANi in AD reactor. Overall, this work provides an easy but feasible way to enhance AD performance by promoting DIET between acetate-producing bacteria and methanogens.

Lignocellulose presents a promising alternative to fossil fuels. Monitoring the mass and size changes of lignocellulosic particles without disrupting the process can assist in adjusting pretreatment and enzymatic hydrolysis, where conventional sieving methods fall short. A method utilizing focused beam reflectance measurement (FBRM) was developed to establish mathematical correlations between FBRM chord information (chord length and count) and particle characteristics (weight and size) quantified through sieving. Results indicate particle size exhibits a linear correlation with the square weighted median chord length (L_sqr) with R² at 0.93. Further, real-time bulk particle mass can be predicted using L_sqr and chord count (R² 0.98). These correlations are applicable in range 53 μm to 358.5 μm. Real-time monitoring of enzymatic hydrolysis of corn stalks has demonstrated the practical applicability of FBRM. This study introduces a novel approach for online characterization of lignocellulosic particles, thereby enhancing lignocellulosic biorefineries.

In this work, carbonization and subsequent activation procedures were adopted to synthesize waste shea butter shells into oxygen-rich interconnected porous activated carbon (SAC_x, x is the mass ratio of KOH used for activation). The SAC_1.5 electrode material showed outstanding electrochemical performance with high specific capacitance (286.6 F/g) and improved rate capability, owing to various synergistic effects originating from a high specific surface area (1233.5 m²/g) and O-rich content. The SAC_1.5-based symmetric device delivered an impressive specific capacitance of 91.6 F/g with a high energy density of 12.7 Wh/kg at 0.5 A/g. The device recorded 99.9 % capacitance retention after 10,000 charge-discharge cycles. The symmetric supercapacitor device successfully lit an LED bulb for more than 1 h, signifying the potential of bio-waste as an efficient carbon precursor for electrode material in practical supercapacitors. This work offers an efficient, affordable, and environmentally friendly strategy for potential renewable energy storage devices.

Cyanobacteria hold promise for simultaneous carbon capture and chemicals production, but the regulation and effect of nitrogen (N) and phosphorus (P) remains unclear. This study investigates major productions of glycogen, protein, and C-phycocyanin (C-PC) in Cyanobacterium aponinum PCC10605 under different N/P levels, alongside changes in light and CO₂. Increasing nitrate (NO₃^–) from 2 to 6 mM resulted in a 9.7-fold increase in C-PC and reduced glycogen to 8.9 %. On the other hand, elevating phosphorus from 0.1 to 2 mM under limited nitrogen enhanced biomass and glycogen through the upregulation of carbonic anhydrase, ADP-glucose pyrophosphorylase, and glycogen phosphorylase. Changes in phosphorus levels and CO₂ inlet concentrations affected metabolites accumulation and carbon capture efficiency, leading to the best condition of 76 % uptake capacity in direct air capture (DAC). All findings underscore the trade-off between glycogen and protein, representing the importance of N/P levels in nutrient modulation of PCC10605.

Microalgae extracellular polymeric substances (EPS) are complex high-molecular-weight polymers and the physicochemical properties of EPS strongly affect the core features of microalgae cultivation and resource utilization. Revealing the key roles of EPS in microalgae life-cycle processes in an interesting and novelty topic to achieve energy-efficient practical application of microalgae. This review found that EPS showed positive effect in non-gas uptake, extracellular electron transfer, toxicity resistance and heterotrophic symbiosis, but negative impact in gas transfer and light utilization during microalgae cultivation. For biomass harvesting, EPS favored biomass flocculation and large-size cell self-flocculation, but unfavored small size microalgae self-flocculation, membrane filtration, charge neutralization and biomass dewatering. During bioproducts extraction, EPS exhibited positive impact in extractant uptake, but the opposite effect in cellular membrane permeability and cell rupture. Future research on microalgal EPS were also identified, which offer suggestions for comprehensive understanding of microalgal EPS roles in various scenarios.