Correction: Effect of the HXBM408 bacteria on rat intestinal bacterial diversity and the metabolism of soybean isoflavones.

[This corrects the article DOI: 10.1371/journal.pone.0253728.].

Effect of the HXBM408 bacteria on rat intestinal bacterial diversity and the metabolism of soybean isoflavones.

The purpose of this study was to investigate the effect of the HXBM408 bacteria on the diversity of rat intestinal bacteria and the metabolism of soybean isoflavones. The control group was administered sterilized water and daidzein by gavage for 7 days. Conversely, the experimental group was administered HXBM408 solution and daidzein by gavage for 7 days. The content of the daidzein metabolite equol in rat feces in the experimental group was significantly higher than that in the control group (P < 0.05) on the 7th and 14th days. However, the content of daidzein and its metabolites in feces was not significantly different (P > 0.05). On the 7th day, the relative abundance of Streptococcus in the feces of the experimental group was significantly higher than that of the control group (P < 0.05), but the difference disappeared over time (P > 0.05). In the intestinal digesta of rats, the proteobacteria of the experimental group was significantly lower than those of the control group (P < 0.05). HXBM408 can increase the degradation ability of soybean isoflavones in a short period after ingestion, increase the number of beneficial intestinal flora, and improve the structure of the flora.

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

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.