The CH4 emissions were positively correlated with HRT (26.3 μmol/cm2.min under 24 h HRT of the floating bed AS system). The N2O emissions were positively correlated with nitrogen loading, and the N2O emissions from the floating bed AS system were lower due to an abundance of N2O-reducing bacteria. The floating media enhanced the biological treatment efficiency while maintaining the bacterial community in the system. However, the floating media promoted CH4 production under anoxic conditions. The originality of this research lies in the use of floating media in the biological treatment system to mitigate GHG emissions, unlike existing research which focused primarily on enhancement of the treatment efficiency.The aim of this work was to study an innovative alkaline process on two cover crops. CaO load of 60 g.kgTS-1 was implemented to combine the functions of storage and pretreatment. Lab-scale reactors were monitored for 180 days to assess the effect of this process on the physico-chemical properties of the biomass. From the first days, pH was not maintained in an alkaline zone and microbial fermentation activity was observed with the degradation of available carbohydrates and production of metabolites, CO2 and H2. High butyric acid accumulation was observed and mass losses of 18.1% and 9.0% of initial VS occurred for oat and rye, respectively. https://www.selleckchem.com/products/Nolvadex.html However, no methane potential loss was recorded in the short and long term and the crops were efficiently preserved. The pretreatment had no major impact on fiber solubilization, and no increase in BMP was obtained, which was attributed to the short duration of the alkaline conditions.This study revealed core bacterial metabolic mechanisms involved in carbon (C) and nitrogen (N) in composting with adding MnO2. Two tests (control group (CK), adding MnO2 (M)) were performed. The results indicated that the MnO2 accelerated the transformation of carbon and nitrogen in composting. Core bacteria involved in the C and N conversion were identified, the complementarity effects of core bacteria were stimulated in M composting. Additionally, the influence of core bacteria on the C and N conversion could be divided into two pathways in M composting. One was that core bacteria promoted C and N conversion by accelerating the flow of amino acids into the tricarboxylic acid cycle. Another was that the complementarity effects of core bacteria increased the overall bacterial diversity, which contributed to C and N conversion. These findings showed that the addition of MnO2 to composting was a promising application to treat agricultural organic waste.Although the high nitrogen content of chicken manure (CM) poses major challenges for methane production through anaerobic digestion, on the bright side, it has a great potential for production of value-added intermediate products, such as volatile fatty acids (VFAs). However, in order to enhance VFAs yield, methane formation should be substantially suppressed. In the current research, individual and multiple effects of initial pH, heat-shock pretreatment, chemical methanogens inhibitor and the inoculum to substrate ratio (ISR) on optimization VFAs fermentation from CM were evaluated via batch assays. In this regard, the highest net VFAs yield, 0.53 g-VFA/g-VS, was achieved at conditions with heat-shocked inoculum and CM at ISR 16 and pH uncontrolled. Acetate dominated the VFAs mixture, accounting for up to 75% of total. Increased inoculum content enhanced the bioconversion efficiency to 78% at ISR 13. The study results suggest that alkalinity is a key promoter of VFAs production from CM.Microbial surfactants are a large number of amphipathic biomolecules with a myriad of biomolecule constituents from various microbial sources that have been studied for their surface tension reduction activities. With unique properties, their applications have been increased in different areas including environment, medicine, healthcare, agriculture and industries. The present review aims to study the biochemistry and biosynthesis of biosurfactants exhibiting varying biomolecular structures which are produced by different microbial sources. It also provides details on roles played by biosurfactants in nature as well as their potential applications in various sectors. Basic biomolecule content of all the biosurfactants studied showed presence of carbohydrates, aminoacids, lipids and fattyacids. The data presented here would help in designing, synthesis and application of tailor-made novel biosurfactants. This would pave a way for perspectives of research on biosurfactants to overcome the existing bottlenecks in this field.The enhancement effects of biochar to an anaerobic membrane bioreactor (AnMBR) treating sewage at low temperatures was investigated in this study through analyzing organics removal, digestion performance, mixed liquor properties, membrane resistance, and foulant compositions. The chemical oxygen demand (COD) removal efficiency and the COD converted to methane rate increased by more than 12.5% at 10 °C, mainly because of the promotion of biochar to volatile fatty acids degradation. Although biochar caused higher dissolved organic matter (DOM) concentration in the AnMBR, it improved the filtration property of the bulk sludge and absorbed the hydrophobic DOM. The decreased filtration resistance assisted by biochar leads to a prolonged membrane operation duration over 200%. Surface foulants, especially cake foulants, were largely mitigated by the enhanced scouring intensity of mixed liquor at the membrane surface, and hence, decreasing the cake/gel foulants ratio.The down flow structured bed bioreactor (DFSBR) was applied to treat synthetic acid mine drainage (AMD) to reduce sulfate, increase the pH and precipitate metals in solutions (Co, Cu, Fe, Mn, Ni and Zn) using vinasse as an electron donor for sulfate-reducing bacteria (SRB). DFSBR achieved sulfate removal efficiencies between 55 and 91%, removal of Co and Ni were obtained with efficiencies greater than 80%, while Fe, Zn, Cu and Mn were removed with average efficiencies of 70, 80, 73 and 60%, respectively. Sulfate reduction increased pH from moderately acidic to 6.7-7.5. Modelling data confirmed the experimental results and metal sulfide precipitation was the mainly responsible for metal removal. The main genera responsible for sulfate and metal reduction were Geobacter and Desulfovibrio while fermenters were Parabacteroides and Sulfurovum. Moreover, in syntrophism with SRB, they played an important role in the efficiency of metal and sulfate removal.