Insights on bio-degumming of kenaf bast based on metagenomi and proteomics
Microbia play important roles in kanef-degumming. This study is to identify the key candidate microbia and proteins responsible for the degumming of kenaf (Hibiscus cannabinus) bast. Kenaf bast was cut into species and immersed into microbial fermentation liquid collected from different sites. Fermentation liquid samples were collected at 0, 40, 110 and 150 h and the subjected to the 16S/18S rRNA sequencing analysis and isobaric tag for relative and absolute quantitation (iTRAQ) analysis. The
... AQ) analysis. The microbial (bacterial and fungal) diversity and the differentially expressed proteins/peptides (DEPs) were identified. Results: With the prolonged degumming time, the weight loss rate increased, the bacterial diversity was decreased. [Weeksellaceae], Enterobacteriaceae and Moraxellaceae were rapidly increased at 0~40 h, and then decreased and were gradually replaced by Bacteroidaceae from 40 h to 150 h. Similarly, Chryseobacterium and Dysgonomonas were gradually increased at 0~110 h and then decreased; Acinetobacter and Lactococcus were increased at 0~40 h, followed by decrease. Bacteroides was the dominant genus at 150 h. 18S rRNA-seq showed the gradually decreased Wallemiaichthyophaga and increased Sclerotiniahomoeocarpa LT30 during degumming. iTRAQ data analysis showed Rds1, and pyruvate kinase I was decreased and increased in the kanef-degumming. Other DEPs of ferredoxin I, superoxide dismutase and aconitatehydratase were identified to be related to the Glyoxylate and dicarboxylate metabolism (ko00630). Conclusions: Bacteria including Chryseobacterium, Dysgonomonas, Acinetobacter, Lactococcus and Bacteroidesand fungi like Wallemia ichthyophaga are key candidate microbia for kanef degumming.