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The Agaricus bisporus (Button mushroom) stands out as one of the most prolific edible fungi which offers robust flavor and nutrition. Nonetheless, this mushroom contains high moisture levels and intense respiration. Without appropriate postharvest preservation techniques, the button mushroom readily experiences browning and senescence. To ensure optimum quality, prompt cooling and appropriate storage conditions are essential. This present research investigated the postharvest quality of button mushrooms stored in a controlled atmosphere (CA) with different initial gas compositions. The findings revealed that button mushrooms in the CA group demonstrated considerable enhancements in appearance and overall quality, effectively delaying browning and senescence compared to those in the control group. The optimal gas composition is 1–3% O2 and 15–17% CO2 (CAII), which effectively inhibited the expression of polyphenol oxidase (PPO)- and lactase (LAC)-related genes in the button mushroom, maintaining a high L* value. Furthermore, the application of 1–3% O2 and 15–17% CO2 (CAII) not only preserved visual quality but also extended the postharvest shelf life of the button mushroom by minimizing metabolic activities that contribute to senescence. Moreover, 1–3% O2 and 15–17% CO2 (CAII) storage also reduced the expression levels of genes associated with ethylene synthesis, which is reflected in the gradual decrease in cell membrane permeability. Consequently, this research underscores the critical importance of controlled atmosphere storage in improving the marketability and sustainability of this widely consumed mushroom. [ABSTRACT FROM AUTHOR]

To endow microbial fuel cells (MFCs) with low cost, long-term stability and high-power output, a novel cobalt-based cathode electrocatalyst (Nano-Co@NC) is synthesized from a polygonal metal–organic framework ZIF-67. After calcining the resultant ZIF-67, the as-synthesized Nano-Co@NC is characteristic of cobalt nanoparticles (Nano-Co) embedded in nitrogen-doped carbon (NC) that inherits the morphology of ZIF-67 with a large surface area. The Nano-Co particles that are highly dispersed and firmly fixed on NC not only ensure electrocatalytic activity of Nano-Co@NC toward the oxygen reduction reaction on the cathode, but also inhibit the growth of non-electrogenic bacteria on the anode. Consequently, the MFC using Nano-Co@NC as the cathode electrocatalyst demonstrates excellent performance, delivering a comparable initial power density and exhibiting far better durability than that using Pt/C (20 wt%) as the cathode electrocatalyst. The low cost and the excellent performance of Nano-Co@NC make it promising for MFCs to be used in practice. [ABSTRACT FROM AUTHOR]

A novel composite of iron sulfide, iron carbide and nitrogen carbides (Nano-FeS/Fe3C@NCNTs) as a cathode electrocatalyst for microbial fuel cells (MFCs) is synthesized by a one-pot solid state reaction, which yields a unique configuration of FeS/Fe3C nanoparticles highly dispersed on in situ grown nitrogen-doped carbon nanotubes (NCNTs). The highly dispersed FeS/Fe3C nanoparticles possess large active sites, while the NCNTs provide an electronically conductive network. Consequently, the resultant Nano-FeS/Fe3C@NCNTs exhibit excellent electrocatalytic activity towards the oxygen reduction reaction (ORR), with a half-wave potential close to that of Pt/C (about 0.88 V vs. RHE), and enable MFCs to deliver a power density of 1.28 W m−2 after two weeks' operation, which is higher than that of MFCs with Pt/C as the cathode electrocatalyst (1.02 W m−2). Theoretical calculations and experimental data demonstrate that there is a synergistic effect between Fe3C and FeS in Nano-FeS/Fe3C@NCNTs. Fe3C presents a strong attraction and electron-donating tendency to oxygen molecules, serving as the main active component, while FeS reduces charge transfer resistance by transferring electrons to Fe3C, synergistically improving the kinetics of the ORR and power density of MFCs. [ABSTRACT FROM AUTHOR]