【文獻(xiàn)標(biāo)題】Upgrade the high-load anaerobic digestion and relieve acid stress through the strategy of side-stream micro-aeration: biochemical performances, microbial response and intrinsic mechanisms
Measurements of total solid (TS), volatile solid (VS), chemical oxygen demand (COD), alkalinity and NH4 +-N were conducted in accordance
with standard methods (Gao et al., 2022). pH was determined by pH meter (FE28, METTLER TOLEDO, Switzerland). Gasbags were used to
collect the biogas in the digesters, and the volume was measured by a graduated syringe through repeat extracting the gas from the bag. The
biogas composition and volatile fatty acids (VFAs) were determined by a gas chromatography (Jiedao GC1690, Hangzhou). The operation process of gas chromatography was introduced in detail in previous study (Tian et al., 2021). α-Glucosidase activity, ATP content, coenzyme F420, CAT (catalase), as well as acetate kinase were measured by using the ELISA kit (Shanghai hengyuan biological technology co., LTD). Electron transfer activity (ETS) was measured using the method reported by Wan et al. (2016). Quantification of C, H and O elements using an elemental analyzer (Elementar Analysensysteme GmbH, Unicube). Confocal laser scanning microscope (CLSM) staining and observation was conducted according to the method reported by Chen et al. (2007).