Extracellular polymeric substances (EPS) and extracellular enzymes in aerobic granules
Journal
Drying Technology
Journal Volume
28
Journal Issue
7
Pages
910-915
Date Issued
2010
Author(s)
Abstract
This work highlighted the main cause of vacuole formation, which may contribute to the stability loss for stored granules, using extracellular polymeric substances (EPS) fractionation in conjunction with fluorescence staining approaches. The results showed that the stored granules had an integrated appearance after 30 days' storage. However, their interior was composed of large vacuoles at 30 £gm cryomicrotome sections. After storage, protease activity was bound principally with tightly bound EPS (TB-EPS) fractions, whereas proteins were predominant in the loosely bound EPS fractions (i.e., supernatant and slime), few in the tightly bound EPS fractions (i.e., TB-EPS and pellet). About 74.5% of Mg2+ was present in the supernatant and slime fractions, and only 25.5% of Mg2+ was found in the LB-EPS, TB-EPS, and pellet fractions. The vacuoles were formed as a result of protease hydrolysis reaction at the core regime that breaks the bonds between proteins and cations (mainly Mg2+). This action leaks the proteins and Mg2+ from the TB-EPS to LB-EPS fractions. ? 2010 Taylor & Francis Group, LLC.
Subjects
Aerobic granules
Enzyme
Extracellular polymeric substances
Storage
Type
journal article