Abstract:
Lignocellulose is a promising feedstock to produce biofuels and other biobased products and it is the most abundant sustainable and economical
alternative to fossil resources. It is the sole source of some of these bio-based
products. Many of these products are obtained from the sugars hydrolysed from
the celluloses and hemicelluloses and this bioconversion is a major factor that
determines effective production. Among different methods of conversion
microbial conversion is more effective and a consortium is more effective than
a single strain. This study aimed at isolating efficient cellulose utilizing
bacteria (CUB) from coir retting water, compost, and cow dung by enrichment
with three lignocellulosic substrates i.e. factory tea refuse, grass clippings, and
Palmyra husk. Four enrichments (each with five days incubation at 37°C) in a
basal culture media with the respective cellulosic substrates as the sole source
of carbon. The populations of CUB were determined by plate count method
using Congo-red agar medium (in triplicates per treatment) from which bacteria
with larger clear zones were isolated. CUB densities were subjected to ANOVA
followed by comparison using Duncan’s test. The cellulose utilizing efficiency
of the isolates was tested using the filter paper degradation method. CUB
density increased with the number of enrichments and further enrichments may
give higher densities of bacteria. Grass clippings were the best lignocellulose
substrate supporting CUB and cow dung was the best source of CUB among
the tested. The highest cellulose utilizing efficiency too was found in strains
isolated from cow dung. The isolates are stored for identification and further
testing of cellulose degrading efficiency of different combinations of the
isolates that may yield an efficient CUB consortium.
