Effect of Hydrogen Peroxide on Biohydrogen Production from Melon Fruit (Cucumis melo L.) Waste by Anaerobic Digestion Microbial Community

Biohydrogen (H-2) production has the potential to provide clean, environmentally friendly, and cost-effective energy sources. The effect of increasing oxidative stress on biohydrogen production by acid-treated anaerobic digestion microbial communities was studied. The use of varying amounts of hydrogen peroxide (H2O2; 0.1, 0.2, and 0.4 mM) for enhancing hydrogen production from melon fruit waste was investigated. It was found that H2O2 amendment to the H-2-producing mixed culture increased hydrogen production. Treatment with 0.4 mM H2O2 increased cumulative H-2 output by 7.7% (954.6 mL/L), whereas treatment with 0.1 mM H2O2 enhanced H-2 yield by 23.8% (228.2 mL/gVS) compared to the untreated control. All treatments showed a high H-2 production rate when the pH was 4.5 - 7.0. H2O2-treated samples exhibited greater resilience to pH reduction and maintained their H-2 production rate as the system became more acidic during H-2 fermentation. The application of H2O2 affected the volatile fatty acid (VFA) profile during biohydrogen fermentation, with an increase in acetic and propionic acid and a reduction in formic acid concentration. The H2O2 treatment positively affects H-2 production and is proposed as an alternative way of improving H-2 fermentation..

Automated summary

This study investigated the effect of hydrogen peroxide (H2O2) on enhancing biohydrogen production. It was found that the addition of H2O2 increased the hydrogen production and affected the pH and volatile fatty acid concentration during hydrogen fermentation.