Long-term storage of aerobic granules in liquid media: Viable but non-culturable status
Journal
Bioresource Technology
Journal Volume
166
Pages
464-470
Date Issued
2014
Author(s)
Abstract
Long-term storage and successful reactivation after storage are essential for practical applications of aerobic granules on wastewater treatment. This study cultivated aerobic granules (SI) in sequencing batch reactors and then stored the granules at 4. ¢XC in five liquid media (DI water (SW), acetone (SA), acetone/isoamyl acetate mix (SAA), saline water (SS), and formaldehyde (SF)) for over 1. year. The first four granules were then successfully reactivated in 24. h cultivation. The specific oxygen uptake rates (SOUR) of the granules followed SI. >. SS. >. SA. >. SAA. >. SW. >. SF; and the corresponding granular strengths (10. min ultrasound) followed SI. >. SA = SS. >. SAA. >. SW. >>. SF. During storage the granular cells secreted excess quantities of cyclic-diguanylate (c-di-GMP) and pentaphosphate (ppGpp) as responses to the stringent challenges. We proposed that to force cells in granules (Alphaproteobacteria, Flavobacteria, Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Sphingobacteria, and Clostridia) entering viable but non-culturable (VBNC) status is the key of success for extended period storage of granules. ? 2014 Elsevier Ltd.
Subjects
Aerobic granules
High throughput sequencing
Signaling molecules
Storage
Viable but non-culturable status
SDGs
Type
journal article