Stevia leaf extract has potential as anticancer treatment, researchers find
When fermented with plant-derived bacteria, stevia leaf extract is toxic to pancreatic cancer cells but not to healthy kidney cells

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Prior studies by other researchers indicated that stevia leaf extract demonstrated potential as an anticancer drug, but isolating and applying the specific bioactive components that protect against cancer cells has remained challenging, Danshiitsoodol said. However, fermenting with bacteria can structurally change the extract and produce bioactive metabolites, which are compounds that can impact living organisms.

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Specifically, the team fermented stevia leaf extract with plant-derived Lactobacillus plantarum SN13T strain (FSLE) and compared its effects on pancreatic cancer (PANC-1) cells in the lab, alongside non-cancerous human embryonic kidney cells HEK-293, to the effects of non-fermented stevia extract. The cells utilized in these experiments were acquired from established commercial cell lines.

“Our findings indicate that FSLE demonstrates significantly greater cytotoxicity than the non-fermented extract at equivalent concentrations, suggesting that the fermentation process enhances the bioactivity of the extract,” Sugiyama said. “Notably, FSLE exhibited lower toxicity toward the HEK-293 cells, with minimal inhibition observed even at the highest concentration tested.”

Additional analyses identified chlorogenic acid methyl ester (CAME) as the active anti-cancer compound. When fermented, the concentration of chlorogenic acid in the extract dropped six-fold, indicating a microbial transformation, according to Danshiitsoodol.

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