The purpose of this study is to optimize the composition of the medium for turmeric fermentation and to select competent turmeric fermentation strains using bacterial isolates from kimchi. Initially, 30 isolates from kimchi were cultured in 5% (w/v) yeast extract and 1% (w/v) maltodextrin to determine viability. As a result, eight strains showed a tendency to maintain viability until the fifth day of fermentation. Subsequently, the eight isolates were fermented in an optimum medium for turmeric fermentation, 5% (w/v) yeast extract, 1% (w/v) maltodextrin, and 5% (w/v) turmeric for seven days to determine the viable cell count and antioxidant capacity. The antioxidant capacities of turmeric fermented by the eight isolates were similar or higher than turmeric fermented by Lactococcus lactis KCTC 2013, while maintaining high viable cell counts of both the eight isolates and L. lactis KCTC 2013 until the seventh day of fermentation. The antioxidant capacities of the selected five strains during fermentation might increase possibly due to the biological conversion of active compounds in turmeric by fermentation. Consequently, a total of five strains of the isolates showing higher antioxidant capacity (4.81±0.19-5.81±0.04 VCE/mL) than fermentation day 0 were selected for fermentation of turmeric.
Coffee is a commonly consumed beverage that contains anti-inflammatory compounds such as caffeine, chlorogenic acid, cafestol, trigonelline, and kahweol. Lactobacillus plantarum is a lactic acid bacterium most frequently used in the fermentation of food products of plant origin. L. plantarum is able to degrade some food phenolic compounds and provide high value-added compounds such as powerful antioxidants or food additives approved as flavouring agents. In this study, we investigated the anti-inflammatory effects of coffee extract fermented by L. plantarum on RAW264.7 macrophages. In lipopolysaccharide-stimulated RAW264.7 cells, these coffee extracts exhibited antiinflammatory activities through the reduction of nitric oxide (NO) production and inducible NO synthase expression. Fermented coffee extracts significantly decreased the expression of inflammatory cytokines such as tumor necrosis factor α, interleukin 1β, interleukin 6, and interferon γ. Cyclooxygenase-2, which is one of the key biomarkers for inflammation, was significantly suppressed. These results might be helpful for understanding the anti-inflammatory mechanism of fermented coffee extract on immune cells and, moreover, suggest that fermented coffee extract may be a beneficial anti-inflammatory agent.
A cultivar (Malus domestica cv. Fuji) of apple was selected to make apple peel (AP) powder by three different powdering methods. Frozen AP was thawed and subsequently was dried or ground without drying. After AP was dried by hot-air drying at 60°C or freeze-drying, the dried AP was ground using a conventional blender. Separately, the thawed AP was powered by using a cryogenic micro grinding technology (CMGT). The ground AP and three types of AP powder were extracted using deionized water, 20, 40, 60, 80, or 100% methanol, followed by vacuum evaporation. The total phenolics contents (TPC), total flavonoids contents (TFC), DPPH, and ABTS radical scavenging capacities of each extract were compared to determine an efficient powdering method. Lyophilized AP powder extract using 60% methanol showed the highest TPC and DPPH radical scavenging capacity. In contrast, 60% methanol extract of the powder by CMGT, resulting in the smallest particle, exhibited the highest TFC and ABTS radical scavenging capacity. This study suggests that the extraction yield of bioactive compounds from AP may be varied according to different powdering methods and that a new powdering process such as CMGT may be applicable to develop functional foods efficiently.
Proximate analysis and antioxidant activity of cultivated wild Panax ginseng (CWPG) were investigated to provide fundamental information of CWPG with different ages and to increase its industrial application. Proximate analyses of CWPG with different ages were performed. Extraction of CWPG with different ages was carried out using heatreflux extraction, and their extraction yield, crude saponin content, ginsenoside content, and antioxidant activity were analyzed. Moisture content decreased, but crude fat and crude protein were increased with aging. Extraction yield and crude saponin contents did not show a specific pattern while 5-year-old CWPG revealed the highest extraction yield and crude saponin content. All CWPGs showed typical ginsenoside profiles containing C-K and Rh2 ginsenosides, which are not found in ginseng. The 3-year-old CWPG showed the highest antioxidant activity including total phenolic content, total flavonoid content, and DPPH and ABTS radical scavenging activities. Moreover, 3-year-old CWPG also revealed the highest acidic polysaccharide content. Therefore, these results suggested that 3-year-old CWPG, which is the cheapest, can be used in industrial application due to its high antioxidant activity and acidic polysaccharide content with similar ginsenoside profile compared to 5- and 7-year-old CWPGs.
It is well-known that cultivated wild Panax ginseng has anti-inflammatory effect. However, a comparative study on cultivation period vs biofunctionality is currently lacking. In this study, 70% ethanol extracts of 3-years (yrs)-, 5-yrs-, or 7-yrs-old cultivated wild ginseng were evaluated for their inhibitory effects on RAW264.7 murine macrophages. Specifically, the production of pro-inflammatory cytokines (interleukin-6 [IL-6] and tumor necrosis factor-alpha [TNF-α]), the expression of surface proteins (CD80, CD86, and MHC-II), and the phagocytic properties were investigated. RAW264.7 cells were induced by 500 ng/mL of lipopolysaccharide (LPS) and treated with 0.1, 1, and 10 ppm of samples. LPS-induced IL-6, TNF-α and surface proteins in all samples were downregulated in a dose-dependent manner. Both IL-6 and TNF-α were significantly reduced at 10 ppm of the 7-yrsold sample compared to 10 ppm of 3-yrs- and 5-yrs-old samples. CD80 and CD86 were also reduced at 10 ppm of all samples, and there was no difference among samples. The phagocytosis has no difference except in 10 ppm of 3 yr-old sample. The results suggest that cultivated wild ginseng extract has anti-inflammatory effect without decreasing phagocytosis.
We attempted to investigate antibacterial and proteolytic activities of bacteria isolated from three ethnic fermented seafoods in the east coast of South Korea, gajami sikhae, squid jeotgal, and fermented jinuari (Grateloupia filicina). Bacillus cereus ATCC 14579, Listeria monocytogenes ATCC 15313, Staphylococcus aureus KCTC 1916, Escherichia coli O157:H7 ATCC 43895, and Salmonella enterica serovar Typhimurium ATCC 4931 were selected to determine the antibacterial activity of the bacterial isolates. Among 233 isolates from the three foods, 36 isolates (15.5%) showed antibacterial activity against B. cereus ATCC 14579, the highest incidence of inhibition, followed by S. aureus KCTC 1916 (7.7%) and L. monocytogenes ATCC 15313 (6.0%). However, only five and three strains among the isolates exhibited inhibitory activity against Gram-negative indicators, E. coli ATCC 43895 and Sal. enterica ATCC 4931, respectively. The proteolytic activity of the isolates was determined via hydrolysis of skim milk after 24, 48, and 72 h incubation. After 72 h incubation, 72 out of 233 isolates (30.9%) showed proteolytic activity, and the isolates of fermented jinuari exhibited the highest incidence of proteolytic activity (60%, 36 isolates). These results suggest that ethnic fermented seafoods in the east coast of South Korea might be a promising source of bacterial strains producing antibacterial and proteolytic compounds.
An alkalophilic microorganism, strain DK1122 producing an alkaline protease was identified. DK1122 was isolated from soil collected in central Korea. The strain DK1122 was Gram-positive, 0.7×2-4 μm in size, and its colony was yellowish white, The strain DK1122 was found to be spore-forming, catalase positive, oxidase positive, caseinolytic, and reduce nitrate to nitrite. The protease was produced aerobically on Horikoshi I agar medium (pH 9.0) with 1% (w/v) skim milk at 40°C for 24 h. Through 16S rRNA gene partial sequencing, the strain DK1122 had the 99.7% sequence similarity to 16S rRNA gene sequence of Bacillus pseudofirmus. Based on the biochemical and physiological properties as well as phylogenetic analysis, the isolated strain was named as Bacillus sp. DK1122. It is expected that Bacillus sp. DK1122 may be a promising candidate for a proudcer of an alkaline protease applicable to the food and detergent industries.
Many traditional fermented foods contain diverse bacteria and many lactic acid bacteria (LAB) play important roles for the fermentation of foods such as many dairy foods and kimchi. Especially, Leuconostoc mesenteroides is one of major bacteria in those fermented foods and the development of this species would be expected to be critical for strain improvement as well as the industrialization. Up to now, a lot of plasmids were isolated from Leuconostocs species including Leu. mesenteroides and a number of vector systems has been developed. Many plasmid vector systems using Leuconostocs spp. employ RCR (rolling circle replication) producing single-stranded DNA intermediates or sometimes takes theta replication. These plasmids include the sequences for Pre protein, recombination specific sites such as RSA (recombination site A) and RSB (recombination site B), and single strain origins for RCR replication. This information might be helpful to elucidate the improvement of Leuconostocs spp. and moreover the development of diverse products using Leuconostocs spp.