Recently, a new study published in the《 International Journal of Molecular Sciences 》revealed that Organic Stevia Extract, after being fermented by bacteria isolated from banana leaves, may have the ability to kill pancreatic cancer cells without harming healthy kidney cells. Pancreatic cancer is a highly malignant tumor with a very poor prognosis.
This research was conducted by a team from Hiroshima University in Japan. The results showed that the antioxidant activity and cytotoxicity of the fermented sweet sorghum leaf extract were "significantly enhanced", which could cause damage or death to the experimental pancreatic cancer cells. Further experiments also revealed that this extract could effectively inhibit the proliferation and migration of pancreatic cancer cells.
Narandalai Danshiitsoodol, an associate professor in the Department of Preventive Medicine and Probiotics Science at Hiroshima University and a co-author of the study, said: "The incidence and mortality rates of pancreatic cancer are continuously rising worldwide, with a five-year survival rate of less than 10%. This cancer is highly aggressive, easily metastasizes, and shows significant resistance to existing treatments such as surgery, radiotherapy, and chemotherapy. Therefore, there is an urgent need to develop new highly effective anti-cancer compounds, and medicinal plants are an important potential source."
The power of fermentation
Early studies have shown that certain bioactive components in stevia leaf extract have anti-cancer potential. However, how to effectively separate and apply these components remains a challenge. Research has found that after bacterial fermentation, the structure of stevia leaf extract changes, and new bioactive metabolites are produced, thereby exerting effects on the body.
Masanori Sugiyama, a professor from the Department of Preventive Medicine and Probiotics Science at Hiroshima University, pointed out that microbial transformation has become an effective strategy for enhancing the pharmacological efficacy of natural plant extracts. Professor Sugiyama's laboratory has isolated over 1,300 strains of lactic acid bacteria from fruits, vegetables, flowers, and medicinal plants, and has verified their health benefits.
This study aims to compare the fermented and non-fermented extracts of lactic acid bacteria, identify the key compounds that enhance their biological activity, and ultimately increase the application value of medicinal plants in cancer prevention and treatment.
The fermentation strain used in this study was the plant-derived lactic acid bacteria SN13T. The researchers compared the effects of fermented and unfermented stevia leaf extract on pancreatic cancer cells and non-cancerous human embryonic kidney cells (HEK-293).
Professor Sugiyama stated: "The results show that at the same concentration, the sweet sorghum leaf extract processed by the SN13T strain exhibited significantly higher cytotoxicity against pancreatic cancer cells compared to the unprocessed extract. This indicates that the fermentation process enhanced its biological activity. It is noteworthy that the SN13T strain showed lower toxicity towards HEK-293 cells, and even at the highest tested concentration, it only exhibited a mild inhibitory effect."
Active anti-cancer compounds
Further analysis revealed that the main active component responsible for the anti-cancer effect was p-coumaric acid methyl ester (CAME). The research showed that CAME could exert toxic effects on cancer cells by inhibiting cell proliferation and migration, blocking the cell cycle, and regulating the expression of genes related to apoptosis.
The study also indicated that during the fermentation process, the concentration of the polyphenolic compound chlorogenic acid in the stevia leaf extract decreased by approximately six times, suggesting that significant microbial transformation occurred during the fermentation process.
Professor Danshiitsoodol explained: "This transformation might be caused by a specific enzymatic reaction in the SN13T strain. The results show that compared to chlorogenic acid, CAME exhibits stronger cytotoxicity and pro-apoptotic effects on pancreatic cancer cells."
The research team plans to further verify the efficacy of this fermented extract in mouse models and assess its systemic effects at different doses.
This study has revealed the mechanism of action of lactic acid bacteria SN13T in the fermentation of herbal extracts, and has also provided a new research direction for the potential application of probiotics as natural anti-tumor components.
Trend of reducing sugar
Under the consumption trend of health, low-calorie and good taste, stevia leaf extract, as a natural high-potency sweetener, not only has zero calories but also outperforms traditional sucrose. Therefore, it has become the preferred raw material for food manufacturers to meet market demands.
Earlier this month, Nate Yates, the CEO of PureCircle, a sweetener brand under global supplier Ingredion, shared his insights on the "sugar reduction trend". He stated that Ingredion's exclusive research shows that North American consumers have a significantly higher acceptance of stevia compared to artificial sweeteners, and stevia will play a crucial role in the "sugar reduction trend".
Meanwhile, research conducted by sweetener supplier Cargill also indicates that adding stevia to beverages and drinking water does not affect blood sugar levels, while adding sucrose, glucose or maltodextrin significantly raises blood sugar. Additionally, the participants who consumed stevia beverages consumed fewer calories in their subsequent meals.
