Removal of sugar moieties from ginsenosides has been proposed to increase their biological effects in various disease models. In order to identify strains that can increase aglycone contents, we performed a screening using bacteria isolated from the feces of infants focusing on acid tolerance and β-glucosidase activity. We isolated 565 bacteria and selected Bifidobacterium animalis subsp. lactis LT 19-2 (LT 19-2), which exhibited the highest β-glucosidase activity with strong acid tolerance. As red ginseng (RG) has been known to exert immunomodulatory functions, we fermented RG using LT 19-2 (FRG) and investigated whether this could alter the aglycone profile of ginsenosides and improve its immunomodulatory effect. FRG increased macrophage activity more potently compared to RG, demonstrated by higher TNF-α and IL-6 production. More importantly, the FRG treatment stimulated the proliferation of mouse splenocytes and increased TNF-α levels in bone marrow-derived macrophages, confirming that the enhanced immunomodulatory function can be recapitulated in primary immune cells. Examination of the molecular mechanism revealed that F-RG could induce phosphorylations of ERK, p38, JNK, and NF-κB. Analysis of the ginsenoside composition showed a decrease in Rb1, Re, Rc, and Rb3, accompanied by an increase in Rd, Rh1, F2, and Rg3, the corresponding aglycone metabolites, in FRG compared to RG. Collectively, LT 19-2 maybe used as a probiotic strain to improve the bioactivity of functional foods through modifying the aglycone/glycoside profile.
Bibliographical noteFunding Information:
Acknowledgments: This research was supported by the Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through High Value-added Food Technology Development Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) grant (116030-3) and the Mid-Career Researcher Program funded by the National Research Foundation of Korea (NRF) grant (2015R1A2A1A10053567). This research was also funded by the National Research Foundation of Korea (NRF) grant (NRF-2017R1C1B1006072).
Funding: This research was funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) [116030-3], National Research Foundation of Korea (NRF) grant [2015R1A2A1A10053567] and the Korean government (MSIP) [NRF-2017R1C1B1006072].
© 2019 by the authors. Licensee MDPI, Basel, Switzerland.
All Science Journal Classification (ASJC) codes
- Food Science
- Nutrition and Dietetics