TY - JOUR
T1 - Stoichiometry and kinetics of poly-β-hydroxybutyrate metabolism in aerobic, slow growing, activated sludge cultures
AU - Beun, J. J.
AU - Paletta, F
AU - Van Loosdrecht, M. C.M.
AU - Heijnen, J. J.
PY - 2000/2/20
Y1 - 2000/2/20
N2 - This paper discusses the poly-β-hydroxybutyrate (PHB) metabolism in aerobic, slow growing, activated sludge cultures, based on experimental data and on a metabolic model. The dynamic conditions which occur in activated sludge processes were simulated in a 2-L sequencing batch reactor (SBR) by subjecting a mixed microbial population to successive periods of external substrate availability (feast period) and no external substrate availability (famine period). Under these conditions intracellular storage and consumption of PHB was observed. It appeared that in the feast period, 66% to almost 100% of the substrate consumed is used for storage of PHB, the remainder is used for growth and maintenance processes. Furthermore, it appeared that at high sludge retention time (SRT) the growth rate in the feast and famine periods was the same. With decreasing SRT the growth rate in the feast period increased relative to the growth rate in the famine period. Acetate consumption and PHB production in the feast period both proceeded with a zero-order rate in acetate and PHB concentration respectively. PHB consumption in the famine period could best be described kinetically with a nth-order degradation equation in PHB concentration. The obtained results are discussed in the context of the general activated sludge models.
AB - This paper discusses the poly-β-hydroxybutyrate (PHB) metabolism in aerobic, slow growing, activated sludge cultures, based on experimental data and on a metabolic model. The dynamic conditions which occur in activated sludge processes were simulated in a 2-L sequencing batch reactor (SBR) by subjecting a mixed microbial population to successive periods of external substrate availability (feast period) and no external substrate availability (famine period). Under these conditions intracellular storage and consumption of PHB was observed. It appeared that in the feast period, 66% to almost 100% of the substrate consumed is used for storage of PHB, the remainder is used for growth and maintenance processes. Furthermore, it appeared that at high sludge retention time (SRT) the growth rate in the feast and famine periods was the same. With decreasing SRT the growth rate in the feast period increased relative to the growth rate in the famine period. Acetate consumption and PHB production in the feast period both proceeded with a zero-order rate in acetate and PHB concentration respectively. PHB consumption in the famine period could best be described kinetically with a nth-order degradation equation in PHB concentration. The obtained results are discussed in the context of the general activated sludge models.
KW - Aerobic activated sludge
KW - Dynamic conditions
KW - PHB metabolism
UR - http://www.scopus.com/inward/record.url?scp=0034688444&partnerID=8YFLogxK
U2 - 10.1002/(SICI)1097-0290(20000220)67:4<379::AID-BIT1>3.0.CO;2-2
DO - 10.1002/(SICI)1097-0290(20000220)67:4<379::AID-BIT1>3.0.CO;2-2
M3 - Article
C2 - 10620753
AN - SCOPUS:0034688444
SN - 0006-3592
VL - 67
SP - 379
EP - 389
JO - Biotechnology and Bioengineering
JF - Biotechnology and Bioengineering
IS - 4
ER -