Development of compost maturity and Actinobacteria populations during full-scale composting of organic household waste.
OBJECTIVE
This study investigates changes in microbiological and physicochemical parameters during large-scale, thermophilic composting of a single batch of municipal organic waste. The inter-relationships between the microbial biomass and community structure as well as several physicochemical parameters and estimates of maturation were evaluated.


RESULTS
Analyses of signature fatty acids with the phospholipid fatty acid and ester-linked methods showed that the total microbial biomass was highest during the early thermophilic phase. The contribution of signature 10Me fatty acids from Actinobacteria indicated a relatively constant proportion around 10% of the microbial community. However, analyses of the Actinobacteria species composition with a PCR-denaturing gradient gel electrophoresis approach targeting 16S rRNA genes demonstrated clear shifts in the community structure.


CONCLUSIONS
This study demonstrates that compost quality, particularly maturity, is linked to the composition of the microbial community structure, but further studies in other full-scale systems are needed to validate the generality of these findings.


CONCLUSIONS
The combination of signature lipid and nucleic acid-based analyses greatly expands the specificity and the scope for assessing the microbial community composition in composts. The results presented in this study give new information on how the development of the compost microbial community is connected to curing and maturation in the later stages of composting, and emphasizes the role of Actinobacteria in this respect.
Steger
K
K
Department of Microbiology, SLU, Uppsala, Sweden. kristin.steger@ebc.uu.se
Sjögren
A M
AM
Jarvis
A
A
Jansson
J K
JK
Sundh
I
I
D039903:Actinobacteria / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D001673:Biodegradation, Environmental; D018533:Biomass; D004269:DNA, Bacterial / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005227:Fatty Acids / Q000032:analysis; D006795:Household Products / Q000382:microbiology; D006812:Humic Substances / Q000382:microbiology*; D008055:Lipids / Q000032:analysis; D010743:Phospholipids / Q000032:analysis; D010802:Phylogeny; D025341:Principal Component Analysis; D012037:Refuse Disposal / Q000379:methods; D012987:Soil / Q000032:analysis; D012988:Soil Microbiology; D014866:Waste Products / Q000032:analysis
D004269:DNA, Bacterial; D005227:Fatty Acids; D006812:Humic Substances; D008055:Lipids; D010743:Phospholipids; D012987:Soil; D014866:Waste Products