Journal Article

Understanding of aerobic granulation enhanced by starvation in the perspective of quorum sensing

Zhang, Chen, Sun, Supu, Liu, Xiang, Ma, Buyun, Lee, Duu-Jong, Wan, Chunli

2016

Overview

Three sequencing batch reactors (M1, M2, and M3) were set up to investigate the influence of different lengths of starvation time (3, 5, and 7 h) on aerobic granulation in the perspective of quorum sensing (QS). Autoinducer-2 (AI-2) level was quantified to evaluate the QS ability of aerobic granules. The results indicated that AI-2 level increased steadily during a cycle of sequencing batch reactors, suggesting that starvation was closely related to AI-2 secretion. In the long-term operation, aerobic granules cultivated using a prolonged starvation period had a better integrity and a higher level of cell adhesiveness despite a slower formation speed. With the extension of the starvation period, the total amount of extracellular polymeric substances (EPS) displayed an increasing tendency. EPS with large molecular weight (MW) also reached a higher level using a prolonged starvation period. However, a higher level of AI-2 and cell adhesiveness was observed in M2, which might be related to more stable granules. The results implied that the starvation period could trigger AI-2 secretion and promoted the production of large MW EPS, leading to cell adhesiveness enhancement and granule formation. Therefore, a combination of different starvation periods was proposed in this study in order to improve aerobic granulation.

• Publisher: Springer Berlin Heidelberg,Springer,Springer Nature B.V
• Subject: adhesion / Aerobiosis / Analysis / Bacteria - chemistry / Bacteria - classification / Bacteria - genetics / Bacteria - isolation & purification / Bacterial Adhesion / Bacterial Physiological Phenomena / Batch reactors / Biomedical and Life Sciences / Bioreactors / Bioreactors - microbiology / Biotechnology / Cell signaling / Cellular biology / Chemical oxygen demand / Chromatography / Culture Media - metabolism / Environmental Biotechnology / Extracellular polymers / Granular materials / Granulation / granules / Life Sciences / Microbial Genetics and Genomics / Microbiology / Microorganisms / Molecular weight / Observations / Oxygen - analysis / Oxygen - metabolism / Polymers / Purification / Quorum Sensing / Reactors / Secretion / Sequencing batch reactor / Sewage / Sewage - microbiology / Sludge / starvation / Studies / Water treatment