Accelerated Co-Composting of Textile Waste Using the New Strains and Microbial Consortium: Evaluation of Maturity, Stability and Microbial Activity

In the present work, the impact of three new bacterial strains and their consortium on composting was evaluated using textile waste as a main substrate mixed with paper, cardboard and green waste, The effectiveness of these micro-organisms in accelerating organic matter degradation was tested. For bioaugmentation of composting, three concentrations (4%, 6% and 8%) were applied. Among the three strains tested, one strain and the consortium demonstrated high organic matter degradation potential, achieving a total organic carbon concentration between 19-21%, total Kjeldahl nitrogen between 1.29-1.56%, a C/N ratio between 13-16%, and a temperature exceeding 55 degrees C. In the current study, mature compost was attained in 10 weeks, instead of the 44 weeks required for conventional composting and the 12 weeks achieved with other strains previously used. Identification of the strains by 16S rRNA sequencing revealed that they belonged to Bacillus sp., Paenibacillus sp., and Enterobacter aerogenes, respectively. These strains are recognized for their remarkable potential to breakdown a broad variety of organic matter, including lignocellulosic molecules. Furthermore, incorporation of bacteria into the waste mixture (either separately or as a consortium) extended the thermophilic phase by 2 weeks in this study, especially Bacillus sp., Paenibacillus sp. and consortium, leading to a significant reduction in compost production time. It is noteworthy that the efficacy of these strains was considerably greater compared with the three previous strains (i.e., Streptomyces cellulosae, Achromobacter xylosoxidans and Serratia liquefaciens), which were isolated from compost and used for bioaugmentation in a previous study. Our results demonstrate that bioaugmentation by endogenous microbial strains and/or their consortium significantly accelerates the composting process.