Microbial community structure at different fermentation stages of kutajarista, a herbal formulation

Abstract

Kutajarista is an Ayurvedic fermented herbal formulation prescribed for gastrointestinal disorders. This herbal formulation undergoes a gradual fermentative process and takes around 2 months for production. In this study, microbial composition at initial stages of fermentation of Kutajarista was assessed by culture independent 16S rRNA gene clone library approach. Physicochemical changes were also compared at these stages of fermentation. High performance liquid chromatography-mass spectrometry analysis showed that Gallic acid, Ellagic acid, and its derivatives were the major chemical constituents recovered in this process. At 0 day of fermentation, Lactobacillus sp., Acinetobacter sp., Alcaligenes sp., and Methylobacterium sp. were recovered, but were not detected at 8 day of fermentation. Initially, microbial diversity increased after 8 days of fermentation with 11 operational taxonomic units (OTUs), which further decreased to 3 OTUs at 30 day of fermentation. Aeromonas sp., Pseudomonas sp., and Klebsiella sp. dominated till 30 day of fermentation. Predominance of γ- Proteobacteria and presence of gallolyl derivatives at the saturation stage of fermentation implies tannin degrading potential of these microbes. This is the first study to highlight the microbial role in an Ayurvedic herbal product fermentation.

Keywords: Ayurveda; Fermentation; Kutajarista; Microbial diversity.

Fig. 1

Phylogenetic tree of bacterial OTUs recovered at 0, 8, and 30 day of fermentation. Clones with prefix KA 0D, KA 8D, and KA 30D denotes sequenced clones at 0, 8, and 30 days of fermentation respectively

Fig. 2

Relative abundance of bacterial families in samples at 0, 8, and 30 days of fermentation

Fig. 3

Rarefaction curves for bacterial OTUs recovered at different time point of fermentation i.e. 0, 8, and 30 days