Project description:Population dynamics of methanogenic genera was investigated in pilot anaerobic digesters. Cattle manure and two-phase olive mill wastes were codigested at a 3:1 ratio in two reactors operated at 37 ï¾°C and 55 ï¾°C. Other two reactors were run with either residue at 37 ï¾°C. Sludge DNA extracted from samples taken from all four reactors on days 4, 14 and 28 of digestion was used for hybridisation with the AnaeroChip, an oligonucleotide microarray targeting those groups of methanogenic archaea that are commonly found under mesophilic and thermophilic conditions (Franke-Whittle et al. 2009, in press, doi:10.1016/j.mimet.2009.09.017).
Project description:Identify and characterize two distinct communities, the aerobic community and the anaerobic community in the partial nitritation/anammox reactors using metaproteomics approach
Project description:We developed a mini-chemostat system with 16 reactors, each at a working volume of 40 ml. Sensors measure dissolved oxygen in the reactor, while OD600 is measured in the outflow. We further developed a CO2 and pH sensor array that can be plugged in to the outflow of the reactors. The system was used to characterize yeast physiology at four metabolically different conditions: limitations of glucose, both aerobic and anaerobic, nitrogen, and ethanol. The physiology of yeast cells grown at the four different conditions in the mini-chemostat (MC) system was compared with yeast cells grown in a DASGIP 1L system using RNAseq analysis
2019-02-01 | GSE120188 | GEO
Project description:Anaerobic bioaugmentation in soil
Project description:By using metagenome resolved protein stable isotope probing (protein-SIP) through incubations of identical reactors with 13C labelled bicarbonate over a period of 48 hours, the study aims to map differences in the metabolic behaviour of the microbial community during anaerobic digestion.
Project description:Industrial anaerobic digestion (AD) represents a relevant energy source beyond today’s fossil fuels, wherein organic matter is recycled to methane gas via an intricate and complex microbial food web. Despite its potential, anaerobic reactors often undergo process instability over time, mainly caused by substrate composition perturbations, making the system unreliable for stable energy production. To ensure the reliability of AD technologies, it is crucial to identify microbial- and system responses to better understand the effect of such perturbations and ultimately detect signatures indicative of process failure . Here, we investigate the effect of microalgal organic loading rate (OLR) on the fermentation products profile, microbiome dynamics, and disruption/recovery of major microbial metabolisms. Reactors subjected to low- and high-OLR disturbances were operated and monitored for fermentation products and biogas production over time, while microbial responses were investigated via 16S rRNA gene amplicon data, shotgun metagenomics and metagenome-centric metaproteomics.
Project description:Caldicellulosiruptor bescii is an anaerobic hyper thermophile that can utilize a wide range of substrates. However, inhibitors released from biomass can result in unfavorable growth conditions and limit bioconversion to products. Medium as well as intracellular pH are conditions critical for growth and prone to change in effect of fermentation end or by products such as, CO2, organic acids etc. Growth pH for C. bescii as currently reported is a narrow range of 6.8-7.3. In this study, we examined the physiological and systems level responses of C. bescii to growth at acidic pH. Samples collected from bottles, controlled batch, fed-batch and chemostat systems were subjected to growth, product and integrated omics profiling. It was discovered that in batch reactors, lowering pH from 7.2 to 6.0 at the mid-log phase, led to a significant increase in growth and product yields. Time course transcriptomics data collected from these batch reactors was analyzed to try and get a better understanding of the underlying mechanisms for improved growth.