This study aimed to prepare kombucha, a fermented tea beverage, containing Dendropanax morbiferus (DM) leaves and roots, and analyze its antioxidant and intracellular activities. We compared the pH change, total acidity, radical scavenging activity, and oxygen radical absorbance capacity (ORAC) of kombucha fermented with black tea alone and that with added DM leaves or roots during fermentation. Using RAW 264.7, we evaluated the effects of kombucha containing different DM parts on nitric oxide (NO) production and inflammation-related cytokine content in cells. Kombucha containing ethanol extracts of DM leaves (BTK-E-DML) and roots (BTK-E-DMR) showed higher radical scavenging activity and ORAC 3 d after fermentation than that prepared from black tea alone (BTK-Ori). In an in vitro experiment using RAW 264.7, samples were treated with 8 mg/mL kombucha considering cytotoxicity; the lipopolysaccharide (LPS)-induced NO content significantly reduced after BTK-E-DML and BTK-EDMR treatments compared with that after BTK-Ori treatment. Additionally, the levels of interleukin-6 and tumor necrosis factor-alpha, which were LPS-stimulated inflammatory cytokines, significantly decreased in cells treated with BTK-E-DML and BTK-E-DMR 15 d after fermentation compared with those treated with BTK-Ori. In conclusion, these results demonstrate that kombucha fermented with the leaves and roots of DM increases antioxidant activity and can significantly regulate inflammatory responses at the cellular level.

Materials and Methods
    Materials
    Fermentation
    pH and acidity measurement
    Radical scavenging and absorbance capacity assays
    Nitric oxide assay
    Measurement of inflammation-related cytokineproduction
    Statistical analysis
Results and Discussion
    Effects of DM extracts on pH and acidity in kombucha
    Effects of DM extracts on radical scavenging andabsorbance capacities
    Effects of DM extracts on NO production in RAW264.7 cells
    Effects of DM extracts on inflammation-relatedcytokines in RAW 264.7 cells
국문요약
Acknowledgment
ORCID

• Jie Rong(Department of Food Science and Nutrition, Jeju National University, Jeju Korea)
• Ki-Bae Hong(Department of Food Science and Nutrition, Jeju National University, Jeju Korea)
• Yun Jae Cho(R&D Center, JEJUPANATEK Inc., Jeju Korea)
• Sung-Soo Park(Department of Food Science and Nutrition, Jeju National University, Jeju Korea) Corresponding author