The molecular structure of humic acid (HA) extracted was investigated by FT-IR and 13C CP/MAS NMR spectroscopy during the vermicomposting of sugar industry wastes, viz. pressmud, trash and bagasse for 60 days. A rapid decrease in C/N and lignocellulosic (lignin, cellulose, hemicellulose) content was observed in vermicompost during early phase of the process. The FT-IR and 13C CP/MAS NMR spectra of HA indicated a high rate of change in structure with increase in the alkyl C/O-alkyl C ratio during the process. Aromatic structures and carboxyl groups showed an initial increase but decreased after ∼40 days indicating extensive mineralization during final stages of vermicomposting. © 2006 Elsevier Ltd. All rights reserved.

T S Chandra

Department Of Biotechnology

Biswarup Sen

composting

Fourier transform infrared spectroscopy

Molecular Structure

nuclear magnetic resonance

Sugar (sucrose)

Waste treatment

LIGNOCELLULOSIC BIOFRACTIONATION

SUGAR INDUSTRY WASTES

VERMICOMPOST

Solid wastes

bagasse

carbon

carboxyl group

cellulose

Hemicellulose

Humic acid

Lignin

Lignocellulose

nitrogen

organic matter

Oxygen

industrial waste

mineralization

Spectroscopy

Transformation

article

biotransformation

CARBON NITROGEN RATIO

carbon nuclear magnetic resonance

chemical structure

Extraction

infrared spectroscopy

nonhuman

ORGANIC MATTER TRANSFORMATION

priority journal

reaction analysis

SOLID STATE SPECTROSCOPY

SUGAR INDUSTRY

VERMICOMPOSTING

Agriculture

Animals

Carbon isotopes

HUMIC SUBSTANCES

Magnetic Resonance Spectroscopy

OLIGOCHAETA

Refuse disposal

Soil

Spectroscopy, Fourier Transform Infrared

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Bioresource Technology

Two laboratory-scale systems were set up (i) composting (without earthworms) and (ii) vermicomposting (with earthworms) and were monitored for 60 days after pre-composting. The physico-chemical parameters (pH, C/N, organic matter, NH4+ - N and ash content) showed similar evolution in both systems except a higher NH4+ - N in the initial vermicomposts. However, principle component analysis (PCA) of enzymatic activities and community level physiological profiles revealed differences in the functional response of microbial communities in compost and vermicompost during maturation. Dehydrogenase activity and bacterial counts indicated a steady decrease in biological activity and population during composting, whereas vermicomposting exhibited higher activity on day 30 and a reduction in bacterial counts on day 10. PCA of denatured gradient gel electrophoresis (DGGE) profiles showed divergent dynamics of bacterial communities in two processes. These results indicated differences in the functional response and genetic structure of microbial community in composts and vermicomposts despite similar changes in their physico-chemical parameters. © 2008 Elsevier Ltd. All rights reserved.

Do earthworms affect dynamics of functional response and genetic structure of microbial community in a lab-scale composting system?

Aims: To evaluate bacterial community structure and dynamics in triplicate vermicomposts made from the same start-up material, along with certain physico-chemical changes. Methods and Results: The physico-chemical parameters (pH, temperature, carbon, nitrogen, soluble substances and cellulose) evolved similarly in the triplicate vermicomposts, indicating a steady function. The 16S bacterial gene abundance remained constant over time. To monitor changes in the bacterial community structure, fingerprinting based on capillary electrophoresis single-strand conformation polymorphism was employed. A rise in bacterial diversity occurred after precomposting and it remained stable during the maturation phase. However, a rapid shift in the structure of the bacterial community in the vermicompost replicates was noted at the beginning that stabilized with the process maturation. Multivariate analyses showed different patterns of bacterial community evolution in each vermicompost that did not correlate with the physico-chemical changes. Conclusions: The broad-scale functions remained similar in the triplicates, with stable bacterial abundance and diversity despite fluctuation in the community structure. Significance and Impact of the Study: This study has demonstrated that microbial fingerprinting with multivariate analysis can provide significant understanding of community structure and also clearly suggests that an ecosystem's efficacy could be the outcome of functional redundancy whereby a number of species carry out the same function. © 2008 The Authors.

Fulltext

Journal of Applied Microbiology

Structural divergence of bacterial communities from functionally similar laboratory-scale vermicomposts assessed by PCR-CE-SSCP

Co-composting of filter cake and bagasse; by-products from a sugar mill

Waste Management

Study of the organic matter evolution during municipal solid waste composting aimed at identifying suitable parameters for the evaluation of compost maturity

Journal of Environmental Quality

Degradation of Biomacromolecules during High-Rate Composting of Wheat Straw-Amended Feces

Vermicomposting of crop residues and cattle dung with Eisenia foetida

Soil Biology and Biochemistry

Vermicomposting of wastewater sludge from paper-pulp industry with nitrogen rich materials

Chemolytic and solid-state spectroscopic evaluation of organic matter transformation during vermicomposting of sugar industry wastes

Journal	Data powered by TypesetBioresource Technology
Publisher	Data powered by TypesetElsevier Ltd
ISSN	09608524
Open Access	No