Isolation and identification of an isoflavone reducing bacterium from feces from a pregnant horse

Autoři: Xie Jinglong aff001;  Li Xiaobin aff001;  Zhao Fang aff001;  Wang Chenchen aff001;  Yang Kailun aff001
Působiště autorů: Xinjiang Laboratory of Meat-and Milk-Production Herbivore Nutrition, Xinjiang Agricultural University, Urumqi, Xinjiang, China aff001
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
prolekare.web.journal.doi_sk: 10.1371/journal.pone.0223503


The aim of this research was to isolate bacteria capable of biotransforming daidzein from fresh feces from pregnant horses. A Hungate anaerobic roller tube was used for anaerobic culture. Single colonies were picked at random and incubated with daidzein. High performance liquid chromatography was used to detect whether the isolated bacteria were able to biotransform the substrate. A strain capable of reducing daidzein was selected and characterized using sequence analysis of 16S rDNA, and a phylogenetic tree was constructed. The morphological physiological and biochemical characteristics of the strain were investigated. A facultative anaerobic, Gram-positive bacterium capable of converting daidzein to dihydrodaidzein was isolated and named HXBM408 (MF992210). A BLAST search of HXBM408's 16S rDNA sequence against the GenBank database suggested that the strain has 99% similarity with Pediococcus acidilactici strain DSM (NR042057). The morphological, physiological, and biochemical characteristics of HXBM408 are very similar to those of Pediococcus. Based on these characteristics, the strain was identified as Pediococcus acidilactici. The bacterial strain HXBM408 isolated from the feces of pregnant horses was able to reduce the isoflavone daidzein to dihydrodaidzein.

Klíčová slova:

Bacteria – Gastrointestinal tract – High performance liquid chromatography – Horses – Anaerobic bacteria – Metabolites – Bacterial biochemistry – Physiological properties


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2019 Číslo 11