• The Korean Journal of Food And Nutrition
• /
• v.32 no.5
• /
• pp.494-503
• /
• 2019

The purpose of this study was to investigate the quality and antioxidant properties of three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria. During the fermentation, the pH was lowered and the titratable acidity increased. The viable cell counts of lactic acid bacteria increased 8.44-9.62 log CFU/g. Organic acid content (especially lactic acid) of sweet potatoes increased by fermentation. Also, ${\gamma}$-Aminobutyric acid increased more than 8.6 times by fermentation in all samples. The total polyphenol and flavonoid contents of sweet potato, showed insignificant changes in all samples by fermentation. ABTS radical scavenging activity of all samples slightly decreased by fermentation, but not significantly. DPPH radical scavenging activity decreased slightly by fermentation except Shinyulmi. However, when compared with the varieties, Shinjami showed the highest activity. The reducing power of Shinjami decreased slightly by fermentation, but activity was the highest among all samples. Based on these results, most of the chemical properties and functionality of fermented sweet potato are retained after fermentation, although some antioxidant activity decreases. We suggest that three fermented sweet potato cultivars (Shinyulmi, Hogammi, and Shinjami) using lactic acid bacteria can be used in various applications because of their effective functional properties.

• The Korean Journal of Food And Nutrition
• /
• v.37 no.1
• /
• pp.17-29
• /
• 2024

To increase industrial applicability of Astragalus membranaceus (AM) as immunostimulating materials, hot-water extract (AME) was prepared from AM and fermented with Kimchi-lactic acid bacteria (Lactobacillus sakei & Leuconostoc mesenteroides) to prepare fermented AM-postbiotics (FAME). Although FAME prepared from AM-postbiotics did not show a significant enhancement in macrophage stimulating activity compared to non-fermented AME, crude polysaccharide (FAME-CP) fractionated by EtOH precipitation from FAME showed significantly higher macrophage stimulating activity than AME-CP. Compared to AME-CP, FAME-CP showed dramatic changes in component sugar and molecular weight distribution. FAME-CP was a polysaccharide with a major molecular weight distribution of 113.4 kDa containing Man (44.2%), Glc (19.3%), Gal (10.2%), GalA (10.2%), and Ara (7.4%) as sugar components. FAME-CP with enhanced macrophage stimulatory activity not only increased expression levels of mRNA genes encoding macrophage-activated factors (iNOS, TNF-α, MCP-1, IL-6, and COX-2), but also led the nuclear translocation of activated p65 and c-Jun. In conclusion, crude polysaccharide from AM-postbiotics fermented with lactic acid bacteria could increase industrial applicability as a functional material with enhanced immunostimulating activity than AME-CP.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.49 no.6
• /
• pp.792-799
• /
• 2016

We isolated seven tryptamine-producing bacteria from commercial salted and fermented sand lance (Ammodytes personatus) sauces using an L-tryptophan decarboxylating medium. These tryptamine-producing bacteria, identified using an API kit and 16S rRNA analysis, included Lysinibacillus xylanilyticus (one strain), Lysinibacillus fusiformis (four strains), and Staphylococcus epidermidis (two strains). Lysinibacillus spp. produced the highest levels of tryptamine in culture broth containing 0.5% L-tryptophan, compared with 1.0% and 2.0% preparations. After 72 h of incubation, Staphylococcus epidermidis produced the highest levels of tryptamine ($60.50{\mu}g/mL$ and $664.86{\mu}g/mL$) in culture broth containing 2.0% L-tryptophan. While Lysinibacillus spp. comprised the dominant tryptamine-producing bacteria in sand lance sauces, Staphylococcus epidermidis also showed high tryptamine-producing activity. This is the first report on the isolation and identification of tryptamine-producing bacteria in sand lance sauces.

• Journal of Environmental Science International
• /
• v.26 no.12
• /
• pp.1355-1362
• /
• 2017

This study was performed to evaluate the possibility of application of lactic acid bacteria fermentation to increase the anti-allergic activity of the extracts from Houttuynia cordata Thunb. H. cordata Thunb was fermented on 25, 30, 35 and $40^{\circ}C$ for 5 days by two species of lactic acid bacteria, Leuconostoc mesenteroides 4395 and Lactobacillus sakei 383. The anti-allergic activity of water extracts of H. cordata Thunb was then analyzed both before and after fermentation. Anti-allergic activity was determined in vitro assays by using 5-lipoxygenase (5-LO), cyclooxygenase-2 (COX-2) and ${\beta}$-hexoseaminidase release of RBL-2H3 cells (degranulation marker). The extracts fermented at $35^{\circ}C$ by both bacteria had the highest inhibitory activities against 5-LO, and also higher than the control, and the one fermented at $30^{\circ}C$ by both bacteria had the highest inhibitory activity against COX-2. The degranulation of RBL-2H3 cells induced by IgE-antigen complex was estimated as ${\beta}$-hexoseaminidase release rate as reference of 100%, the release rates were inhibited in $25{\mu}g/ml$ of the extracts fermented at 30, 35 and $40^{\circ}C$ only by L. mesenteroides 4395. These results indicate that anti-allergic activity of H. cordata Thunb is increased by lactic acid bacteria fermentation.

• Asian-Australasian Journal of Animal Sciences
• /
• v.29 no.9
• /
• pp.1273-1279
• /
• 2016

The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB) co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM) supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle ($410{\pm}10kg$) were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate) on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a), potential degradability (a+b) and effective degradability of dry matter (EDDM) linearly (p<0.01) increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b) and rate of degradation (c). In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.

• Food Science and Preservation
• /
• v.20 no.5
• /
• pp.712-719
• /
• 2013

This study was conducted to investigate the antibacterial activity of lactic acid bacteria isolated from traditional fermented foods and to develop a new starter for fermented milk. The isolates were identified using 16S rDNA sequencing and named Lactobacillus plantarum A, Leuconostoc lactis B and L. acidophilus C. The activity of these strains to inhibit the growth of food-borne human pathogens (Escherichia coli NCTC 12923, Salmonella Typhimurium NCTC 12023, Listeria monocytogenes NCTC 11994) was measured using the paper disc method. All these strains showed strong antibacterial activity against Li. monocytogenes NCTC 11994. The experiment groups were the fermented milks with these strains, and the control group was the fermented milk with the commercial starter (ABT 5). The change of pH, acidity and viable cell counts were measured during their aging time. All the experiment groups showed a significant difference in their aging times compared to the control group. However, the sensory test showed that the experiment groups can be used as useful starters for fermented milk. This result suggests that L. plantarum A, Leu. lactis B and L. acidophilus C have the potential to be developed as new starters for fermented milk.

• Journal of Life Science
• /
• v.33 no.6
• /
• pp.506-511
• /
• 2023

The purposes of this study were to isolate and characterize lactic acid bacteria with antibacterial activity against Methicillin-resistant Staphylococcus aureus (MRSA) from fermented food and to confirm the antibacterial activities of fermented rice products using the isolated lactic acid bacterium. Three bacteria, namely, Weissella sp. ISF-1, ISF-2, and ISF-3, were selected from fermented squid based on the 16S rRNA gene sequence. All three strains grew well in an MRS medium containing 5% (w/v) NaCl and showed antibacterial activity against Bacillus cereus, Staphylococcus aureus, and MRSA. Their growth was excellent at 0% ~ 5% (w/v) NaCl and relatively good up to 7% (w/v) NaCl. The initial pH of 8 was optimal for their growth, and good growth was also observed at pH 6, 7, and 9. The lyophilisates of the fermented rice using Weissella sp. ISF-1 showed antibacterial activities against B. cereus, S. aureus, and MRSA. We inferred that isolated lactic acid bacteria could be useful in the development of probiotics and biopreservatives for foods and in the treatment of MRSA and may increase the value of rice products.

• Food Science of Animal Resources
• /
• v.30 no.1
• /
• pp.154-162
• /
• 2010

This study was carried out to compare the efficacy and selectivity of TOS and BS media for enumeration of bifidobacteria in commercial fermented milk products. First, bifidobacteria was isolated from 20 fermented milk products, and all isolated bifidobacteria were identified by genomic technology as Bifidobacterium lactis. The two media significantly differed from each other with regard to the recovery of B. lactis, that is, the recovery of this organism was as much as 6 logs lower on BS medium than on TOS. When the concentration of BS solution (mixture of paromomycin sulfate, neomycin, sodium propionate, and lithium chloride) used in BS medium was reduced to 50% (BS50), a relatively high percentage recovery of bifidobacteria from pure cultures was achieved. Susceptibility tests to antibiotics and tests for selective agents for the isolated bifidobacteria and lactic acid bacteria were conducted. The BS solution inhibited some lactic acid bacteria and Bifidobacterium species, while mupirocin (MU) suppressed the growth of all tested lactic acid bacteria but not Bifidobacterium. As compared with BS50 medium, TOS with or without MU showed good bifidobacteria recovery and readily distinguishable colonies; in particular, TOS supplemented with MU had a high selectivity for bifidobacteria. In conclusion, all results suggested that TOS medium with or without MU was found to be suitable for selective enumeration of bifidobacteria from mixed cultures in fermented milk, and better in that capacity than BS medium.

• Preventive Nutrition and Food Science
• /
• v.7 no.4
• /
• pp.397-404
• /
• 2002

Soybean curd residue (SCR) was fermented by lactic acid bacteria, Lactobacillus rhamnosus LS and Entercoccus faecium LL, isolated from SCR. The pH, titratable acidify and viable cell counts were determined from the fermented SCR to evaluate the lactic acid production and growth of lactic acid bacteria. Optimal amounts of pretense enzyme and glucose, and ideal fermentation time for SCR fermentation were estimated by response surface methodology (RSM). Raw SCR fermented by indigenous microorganisms had 0.78 % titratable acidity, The acid production in SCR fermented by L. rhamnosus LS was greatly enhanced by the addition of glucose and lactose. However only glucose increased acid production by Ent. faecium LL. The proof test of SCR fermentation demonstrated that similar results for titratable acidity, tyrosine content and viable cell counts to that predicted could be obtained by the at optimized fermentation conditions. In the presence of 0.029 % (w/w) pretense enzyme and 0.9% (w/w) glucose, the SCR fermented by Ent. faecium LL showed 1.07% (w/v) of titratable acidity, 1.02 mg% tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts. With the SCR fortified with 0.033% pretense enzyme and 1.7% glucose, L. rhamnosus LS showed 1.8% (w/v) of titratable acidity, 0.92 mg% of tyrosine content and 2$\times$10$^{9}$ (cfu/g) of viable cell counts.

• The Korean Journal of Food And Nutrition
• /
• v.27 no.4
• /
• pp.742-750
• /
• 2014

This study was done in order to investigate the changes in quality of Cheonggukjang for soybean cultivars during fermentation. Cheonggukjang of 14 cultivars that were inoculated with Bacillus subtilis 15893 was produced, and, then, it was measured for hardness, proximate composition, amino nitrogen, enzyme activity, and total aerobic bacteria counts. In a raw bean, the highest hardness value was 16,975 g from Sunyu. In a steaming bean, Jangwon had the highest hardness value and the lowest aerobic bacteria counts of forty-eight hours fermented Cheonggukjang. Saedanbaek, whose protein contents was highest in raw bean, was also highest in Cheonggukjang. The amino nitrogen content of twenty-four hours fermented Cheonggukjang was highest in Saeol and Sunyu while forty-eight hours fermented Cheonggukjang was highest in Singi, Daol, and Milyang 231. In the protease activity, Saedanbaek had the highest and total aerobic bacteria count that were either increased or held as time went on ; twenty-four hours fermented Cheonggukjang was highest in Milyang 231 and Keunol while forty-eight hours fermented Cheonggukjang was highest in Chunsang.