Pectinolytic Bacterial Consortia Reduce Jute Retting Period and Improve Fibre Quality.

Jute fibre is the second most important fibre next to cotton. It is obtained from the bark of plant through microbial retting process. Here we report optimized microbial retting protocol that can lower retting period and produce high fibre quality. A total of 451 bacterial colonies have been isolated from five jute retting water samples in Bangladesh. Higher pectinolytic bacterial isolates were predominant in the later stage of jute retting. Out of these, 168 isolates have been screened by both semi-quantitative and quantitative pectinase, xylanase and cellulase enzyme assay. Among them, 144 isolates have been selected on the basis of extra cellular enzyme activity of these three enzymes. 16 s ribosomal gene sequencing analysis identified 2 phyla- Firmicutis (80.55%) and Proteobacteria (19.45%). To check the synergistic and antagonistic effect 10 selected isolates were tested in 167 different combinations. Three best combinations were identified that lowered retting period from 18-21 days to 10 days producing high quality fibre in both laboratory and field trial. This improved retting technology can be adopted in industrial scale for the production of quality jute fibre in a controlled condition in reduced water quantity without polluting the environment.

Comparative genomics of two jute species and insight into fibre biogenesis.

Jute (Corchorus sp.) is one of the most important sources of natural fibre, covering ∼80% of global bast fibre production1. Only Corchorus olitorius and Corchorus capsularis are commercially cultivated, though there are more than 100 Corchorus species2 in the Malvaceae family. Here we describe high-quality draft genomes of these two species and their comparisons at the functional genomics level to support tailor-designed breeding. The assemblies cover 91.6% and 82.2% of the estimated genome sizes for C. olitorius and C. capsularis, respectively. In total, 37,031 C. olitorius and 30,096 C. capsularis genes are identified, and most of the genes are validated by cDNA and RNA-seq data. Analyses of clustered gene families and gene collinearity show that jute underwent shared whole-genome duplication ∼18.66 million years (Myr) ago prior to speciation. RNA expression analysis from isolated fibre cells reveals the key regulatory and structural genes involved in fibre formation. This work expands our understanding of the molecular basis of fibre formation laying the foundation for the genetic improvement of jute.