Sphingobacterium jejuense sp. nov., with ginsenoside-converting activity, isolated from compost

Area of Science:

• Microbiology
• Bacteriology
• Taxonomy

Background:

• Compost microbiota harbors diverse bacterial species with unique metabolic capabilities.
• Understanding bacterial taxonomy is crucial for elucidating ecological roles and potential applications.
• Ginsenosides are bioactive compounds in ginseng with significant pharmacological interest.

Purpose of the Study:

• To taxonomically classify a novel bacterium isolated from compost.
• To investigate the metabolic potential of the isolate, specifically its ability to transform ginsenosides.
• To propose a new species within the genus Sphingobacterium.

Main Methods:

• Polyphasic taxonomic characterization including phenotypic and genotypic analyses.
• 16S rRNA gene sequencing for phylogenetic analysis.
• Enzymatic assays to determine beta-glucosidase activity and ginsenoside transformation.

Main Results:

• Strain GJ30-7T was characterized as a Gram-negative, aerobic, non-motile bacterium.
• Phylogenetic analysis placed the isolate within the genus Sphingobacterium, closely related to S. yanglingense.
• The bacterium demonstrated beta-glucosidase activity, transforming ginsenosides Rb1 and Rc to F2.
• Distinct genotypic and phenotypic features differentiated GJ30-7T from known Sphingobacterium species.

Conclusions:

• The novel isolate, GJ30-7T, represents a new species, Sphingobacterium jejuense sp. nov.
• Sphingobacterium jejuense possesses the enzymatic machinery for ginsenoside biotransformation.
• This discovery expands the known diversity within the Sphingobacterium genus and highlights potential biotechnological applications.