In this study, fermented products of yeast and acetic acid bacteria were prepared using coffee bean extracts, and evaluated the fermentation characteristics and functionality of fermented products respectively. Roasted coffee extract was manufactured mixed solution (70% coffee extract, 20% glucose, 1% yeast extract) for yeast fermentation with Saccharomyces cerevisiae SRCM102539 and fermented for 5 days. During the yeast fermentation period (5 days), the live cell counts and physicochemical properties (soluble solid content, pH and total acidity), free sugar, organic acid and ethanol contents were analyzed. The live cell counts, soluble solids, pH and total acidity of UFRCE (day 0, unfermented roasted coffee extract) were 4.50 log CFU/mL, 21.27°Brix, 4.99, 0.21%, and FRCE (day 5, fermented roasted coffee extract) were 6.72 log CFU/mL, 7.60°Brix, 4.56, 0.30%, respectively. The organic acids of FRCE were succinic acid (373.00 mg%), acetic acid (190.91 mg%), and citric acid (67.41 mg%), respectively. The glucose content of UFRCE was 23.89% (w/v), but FRCE was not detected. The ethanol content of UFRCE was not detected, but FRCE was detected 8.41% (w/v). The anti-inflammatory effect of UFRCE and FRCE were evaluated in lipopolysaccharide (LPS, 1 μg/mL)-induced inflammatory reactions in RAW 264.7 cells. UFRCE was decreased nitric oxide (NO), prostaglandin2 (PGE2), tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) production in RAW 264.7 cells by 26.01%, 31.70%, 32.31%, 62.10% and FRCE was decreased 41.82%, 55.71%, 40.14%, 71.13%, respectively, at concentration of 0.5 mg/mL. UFRCE were inhibited activation of iNOS and COX-2 expression 50.28%, 20.01% and FRCE were inhibited 58.01%, 41.23%, respectively. FRCE showed higher anti-inflammatory activity than UFRCE, and this activity was increased by yeast fermentation.
Roasted coffee liquor (70% coffee extract, 5% glucose, 1% yeast extract, 6% ethanol) was manufactured for seed culture with Acetobacter pasteurianus CT_02 and fermented for 8 days. Acetic acid bacteria fermentation was performed by adding 30% (v/v) of seed culture to coffee wine. During the acetic acid bacteria fermentation period (15 days), the live cell counts and physicochemical properties (soluble solid content, pH and total acidity), free sugar, organic acid and ethanol contents were analyzed. The live cell counts, soluble solids, pH and total acidity of AUFCW (day 0, acetic acid unfermented coffee wine) were 6.35 log CFU/mL, 8.10°Brix, 3.88, 1.29%, and AFCW (day 15, acetic acid fermented coffee wine) were 4.40 log CFU/mL, 8.57°Brix, 3.07, 7.45%, respectively. The organic acids of AFCW were acetic acid (5921.43 mg%), succinic acid (434.94 mg%) and citric acid (69.43 mg%), respectively. The antibacterial activity was increased as the acetic acid fermentation progressed, and AFCW showed the highest antibacterial activity in B. cereus KTCT1661 and S. aureus KCCM11593 strains. The pancreatic lipase inhibitory activity also increased according to the fermentation period, and the 50% inhibitory activity (IC50) values of the fermentation products on the 10th and 15th days were 226.94 and 334.48, respectively, at the dilution factor. The anti-obesity effect of AUFCW and AFCW were evaluated in lipid accumulation rate, leptin protein expression level, and adipogenesis-related genes at the mRNA level. AUFCW was decreased lipid accumulation rate, leptin protein expression in 3T3-L1 cells by 15.66%, 18.80%, and AFCW was decreased 30.63%, 49.80%, respectively, at a concentration of 0.2 mg/mL. AUFCW were inhibited activation of PPAR-γ and SREBP-1c expression 13.47%, 36.75% and AFCW were inhibited 21.84%, 50.79%, respectively. AFCW showed higher antibacterial activity and anti-obesity effect than AUFCW, and these activities were increased by acetic acid bacteria fermentation.