Development of compost maturity and Actinobacteria populations during full-scale composting of organic household waste

Abstract

Aims: 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. Methods and 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. Significance and Impact of the Study: 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.

Use of the co-composting time extract agar to evaluate the microbial community changes during the co-composting of activated sludge and date palm waste

“…Pérez et al (2002) and Nakasaki et al (2009) showed that actinobacteria produce an active enzyme to degrade lignocellulotic compounds. Tuomela et al (2000); Steger et al (2007) and Xiao et al (2011) have shown that actinomycetes are activated later and contribute to the degradation of recalcitrant compounds and the formation of the stable compounds of ''humic substance''.…”

“…Chroni et al (2009) explained that the thermophilic fungi exhibited a small increase as temperature rose in the first month of composting, stabilizing thereafter. Steger et al (2007), showed that fungi and actinobacteria commonly proliferate during periods with comparatively low temperatures (\45°C). Several authors show that the final phase, which includes both coolingdown and maturation stages, is characterised by the development of a new mesophilic fungal community (Finstein and Morris 1975;Ishii et al 2000).…”

“…In order to evaluate the process and the end product biotransformation, better knowledge of the functional microbial community dynamics is needed. Steger et al (2007) showed that knowledge of the microorganism composition in composts, their community structure and the microbial succession should help to ensure high quality of the final compost product. It has been underlined that microbial activity during composting is mainly due to the mesophilic microbial community, such as (bacteria, fungi and actinobacteria) which play an important role in breaking down the organic compounds to humus-like material (Finstein and Morris 1975;Herrmann and Shann 1997;Ryckeboer et al 2003).…”

Bacteria community analysis of compost by denaturing gradient gel electrophoresis (DGGE) method

“…Sự tồn tại các nhóm vi sinh vật theo từng giai đoạn và phụ thuộc vào nguồn carbon hữu cơ hòa tan, tỷ lệ thay đổi C/N [2], cũng như nhiệt độ và pH trong các giai đoạn phân hủy trong báo cáo của Cahyani (2003) [1] cho thấy cộng đồng vi khuẩn trong phân bón của rơm rạ như Alphaproteobacteria trong nguyên liệu, Bacillus và Actinomycetes ở giai đoạn ưa nhiệt và Cytophaga và Clostridial. Theo kết quả nghiên cứu của Steger (2007) [13] cho thấy thay đổi thành phần trong cộng đồng Actinobacteria trong quá trình ủ thải hữu cơ theo quy mô của hộ gia đình. Trong thí nghiệm này, chúng tôi chọn phân chuồng ủ từ các hộ gia đình theo phuơng thức truyền thống, nên quá trình tách chiết và tinh sạch cũng như nhân bản đoạn gene 16S rDNA cho kết quả thường không ổn định xem hình 1.…”

Microbial Conversion of Vegetable Wastes for Bio fertilizer Production

“…The internal tissues are nutrient rich and have a pH nearly neutral because the principal storage polymer is starch. During the composting process, various parameters including C:N ratio, composting temperature, pH of the finished product, moisture content and the presence of potential pathogens such as coli form bacteria are used to assess the quality and stability of the compost (Wu and Ma 2002;Steger et al, 2007;Sanmanee et al, 2011). In the present study, a simple microbiological process, this could provide a solution to the problem of kitchen waste disposal, and for recycling of solid waste into useful manure by the action of decomposing bacteria.…”