Fermented Pueraria lobata root extract and Glycine max extract showed estrogen-like activities, reducing depressive symptoms in menopausal mice but not increasing female cancer risks.
The researchers focused on Pueraria lobata roots and Glycine max (also known as soybeans) extracts, which are rich in isoflavones but often limited in practical use due to their high molecular weight and low bioavailability. The researchers chose to ferment these extracts with Lactiplantibacillus plantarum strains which are known to convert glycosides to aglycones, potentially enhancing the beneficial effects of the isoflavones. Specifically, the study was conducted using ovariectomized mice.
The research found that both fermented Pueraria lobata root extract and Glycine max extract exhibited estrogen-like activities. More intriguingly, the fermentation process increased the expression of estrogen receptor beta, suggesting that these extracts may not increase the risk of various female cancers—a common side effect of hormone replacement therapy—as was previously believed. Also, the ingestion of these extracts not only increased the estrogen receptor beta in the mice but also upregulated the expression of the brain-derived neurotrophic factor in the hippocampal region of the brain, thus improving depressive symptoms. The highest expression was observed in the group given a mixture of both extracts.