• Korean journal of food and cookery science
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• v.13 no.3
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• pp.286-292
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• 1997

The purpose of this study was to investigate the effect of citron (Citrus junos) on Dongchimi (watery radish kimchi) fermentation. Dongchimi with various levels (0, 1, 2, 4, 6％) of citron was fermented at 10$^{\circ}C$ for 36 days. The pH of Dongchimi decreased slowly in all samples during fermentation, however, it was slightly lower in citron-added Dongchimi. Total acidity and turbidity of Dongchimi increased gradually during formentation, in which the level of increase was greater as the ％ of added citron increased. However, the total acidity and turbidity of Dongchimt without citron increased dramatically on 36$\^{th}$/ day of fermentation, and reached the values similar to those of Dongchimi with 6% citron. Reducing sugar content increased gradually up to 15∼23 days of fermentation and decreased rapidly for the rest of the period. The content of vitamin C was much higher in citron-added Dongchimi, and especially it was 4 times higher than that of without citron at the beginning of fermentation. The number of lactic acid bacteria reached the maximum on 15$\^{th}$/ day in citron-added Dongchimi and on 30$\^{th}$/ day in Dongchimi without citron, and decreased thereafter.

• Food Science and Preservation
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• v.12 no.4
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• pp.395-401
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• 2005

This study was carried out to investigate the changes in the fermentation characteristics of Kimchi prepared with various salts (Korean solar salt, Chinese solar salt, washed and dehydrated salt, purified salt and a processed salt). Acidity appeared to increase most rapidly in Kimchi prepared with Korean solar salt and reached higher level. Total microbial count slowly increased at the beginning of fermentation and reached maximum on 6 days, then decreased slowly. The number of lactic acid bacteria was rapidly increased up to $4{\sim}6$ days, and thereafter decreased slowly. In conclusion, any significant differences in fermentation characteristics analyzed was not observed in Kimchi prepared with various salts except acidity.

• Analytical Science and Technology
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• v.31 no.6
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• pp.219-224
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• 2018

The fruit and stem of Opuntia ficus-indica var. aboten (OFS), a native plant of Jeju Island, are considered a safe food source. Moreover, stem extracts have been previously reported to possess a variety of biological effects (e.g. anti-inflammatory and anti-oxidant, including the ability to partially ameliorate cognitive impairment), suggesting that this plant may have utility as a functional food. The present study investigated whether fermentation by lactic acid bacteria enhances the biological effects of OFS extracts. The acetylcholinesterase (AChE) inhibitory activity of fermented or non-fermented OFS extracts was evaluated, and the content of marker components dihydrokaempferol (DHK) and quercetin-3-methyl ether (3-MeQ) was analyzed using high-performance liquid chromatography. Fermented (relative to non-fermented) OFS extracts exhibited improved AChE inhibitory activity ($IC_{50}=28.35 mg/mL$), with AChE inhibitory activity resulting from fermentation by L. plantarum ($IC_{50}=12.56mg/mL$) exceeding that resulting from fermentation by L. fermentum ($IC_{50}=17.71mg/mL$). Furthermore, fermented (relative to non-fermented) OFS extracts exhibited a 16.7 % increase in DHK content, and 3-MeQ content of OFS extracts fermented by L. plantarum and L. fermentum increased by 28.6 % and 21.4 %, respectively. Therefore, OFS stem extract AChE inhibitory activity, as well as DHK and 3-MeQ content, was enhanced by fermentation with Lactobacillus spp. This suggests that fermented OFS extracts may contribute to prevention or improvement of cognitive impairment. These data are anticipated to be useful in the development of enhanced-efficacy OFS products.

• Journal of Life Science
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• v.23 no.5
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• pp.682-688
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• 2013

We investigated a physiological function by fermenting a medicinal mushroom, (Cudrania tricuspidata fruit). A fermentation using lactic acid bacteria and the extracts isolated from 70% ethanol fractionation was included in cultured mouse spleen cells for cytokine secretion. As a result, total polyphenol content improved by 47% by organic acid fermentation. This was regarded as immune activity in fermented C. tricuspidata fruits, as the levels of interleukin (IL)-2 and IL-4 secretion increased. In addition, when the extracts were treated with a stimulant lipopolysaccharide, the secretion of helper T (Th) 1 cytokines IL-2, IL-12, and tumor necrosis factor-${\alpha}$ was suppressed, while the secretion of Th2 cytokines IL-4, IL-5, IL-6, and IL-10 significantly increased. Therefore, this study suggests that fermentative C. tricuspidata fruit extracts can contribute to the suppression of cellular immune reactions induced by the expression of Th1 cells and activation of the expression of Th2 cells inducing humoral immune reactions associated with the antibody generation by B lymphocytes.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2112-2118
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• 2017

Leuconostoc mesenteroides is used as a starter to produce high-quality kimchi products. In this study, an efficient and economical cabbage juice medium (CJM) was developed by process optimization of cabbage extraction and pasteurization and by compositional supplementation of various lacking nutrients. The pasteurized cabbage juice was determined to be a good medium candidate to cultivate L. mesenteroides, showing maximal cell numbers ($9.85{\times}10^8CFU/ml$) after 24 h. Addition of sucrose and yeast extract with soy peptone resulted in increment of bacterial cell counts in CJM, showing the supplementing effect of the lacking nutrients. Furthermore, addition of shell powder gave a protective effect on bacterial cells by preventing pH decline and organic acid accumulation in CJM, resulting in a 2-fold increase of bacterial counts. The optimized composition of CJM was 70% cabbage juice diluted with water, 0.5% (w/v) sucrose, 1% (w/v) yeast extract, 1% (w/v) soy peptone, and 1.5% (w/v) ark shell powder. The CJM developed in this study was able to yield a comparable level of bacterial counts with MRS medium and reduced the cost by almost 10-fold.

• Food Science of Animal Resources
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• v.32 no.5
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• pp.635-643
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• 2012

As an appraisal for the application of a new starter culture, more than 200 lactic acid bacteria strains were isolated from raw milk and healthy human feces. The strains showing excellent growth and acid production ability in 10% skim milk media were selected and identified as Lactobacillus casei based on the results of their API carbohydrate fermentation patterns, as well as 16S rDNA sequence analysis. To assess the effect of L. casei strains on irritable bowel disease (IBD), the inhibitory effect of the selected strains against the nitric oxide (NO) production of lipopolysaccharide (LPS)-stimulated RAW 264.7 cells was measured. Among the tested L. casei strains, L. casei MCL was observed to have the greatest NO inhibitory activity. Additionally, L. casei MCL was found to inhibit mRNA expression of pro-inflammatory cytokines (interleukin-$1{\beta}$, IL-6, TNF-${\alpha}$), as well as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) involved in pathophysiologic processes such as inflammation. The mRNA expression of anti-inflammatory cytokines, including IL-10 and transforming growth factor-$1{\beta}$ (TGF-${\beta}$) of L. casei MCL, was confirmed using quantitative real-time PCR. In conclusion, L. casei MCL showed decreases in the expression of pro-inflammatory cytokines and up-regulated expression of the anti-inflammatory cytokine.

• Food Science of Animal Resources
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• v.26 no.2
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• pp.252-256
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• 2006

This study was carried out to investigate characteristics of acid and alcohol fermented milk by mixed starters made by Lactobacillus bulgaricus (KCTC 3635) and Kluyveromyces marxianus (KCTC 17212) for 36 hours when the curds were formed. Final pH and titratable acidity were about 4.5 and 0.68%, respectively. The viable cell counts of lactic acid bacteria and yeast for alcohol fermented milk were increased to $3.2{\times}10^9 CFU/mL$ and $5.3{\times}10^9 CFU/mL$, respectively. The ethanol contents increased to 0.35% during fermentation. Antitumor activities of the fermented milk against tumor cell lines, such as HEp-2, HEC-1B, SW-156 and SK-MES-1 showed to 86.6, 70.3, 60.4 and 57.14%, respectively.

• Journal of Dairy Science and Biotechnology
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• v.39 no.4
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• pp.157-165
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• 2021

This study aimed to determine the effect of extraction temperature and time on the antioxidant activity of hot water extract from Panax ginseng sprout powder and to evaluate the suitability of this extract for use in dairy products. Water-soluble fractions of commercial Panax ginseng sprout powder were obtained by hot water extraction at 25, 60, or 80℃ for 0.5, 2, 12, or 24 h. The antioxidant activity of each extract was evaluated by measuring its free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS). DPPH and ABTS free radical scavenging activity increased with extraction temperature from 25 to 80℃. At 80℃, increasing the extraction time from 0.5 to 2 h led to increases in DPPH and ABTS free radical scavenging activity. Thus, the extract obtained under 2 h at 80℃ was selected for addition to milk and yogurt. After 16 days of storage, there were no significant changes in the pH of the milk or the antioxidant activity of the extract. With regard to yogurt fermentation, adding the extract did not affect the pH or the number of viable lactic acid bacteria. In conclusion, hot water extract from Panax ginseng sprout powder can be added to dairy products to enhance antioxidant activity.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.231-240
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• 2015

In this study, a total of 16 conjugated linoleic acid (CLA) producing lactic acid bacteria (LAB) were isolated from fermented foods. Among those strains, the S48 and P1201 strains were capable of producing higher CLA contents than other LABs. The two strains were classified as Lactobacillus plantarum based on morphological, physiological, chemotaxonomic, and molecular-genetic properties. The survival rates of these strain appeared to be 59.57% and 62.22% under artificial gastric conditions after 4 h at pH 2.5, respectively. These strains produced the cis-9, trans-11, and trans-10, cis-12 CLA isomers from 8% skim milk medium supplemented with the different free LA concentration at $37^{\circ}C$ for 48 h and the production of two CLA isomers constantly increased in the growth until 48 h of incubation. After 48 h of fermentation, the levels of CLA appeared highest in steamed soy-powder milk than fresh and roasted soy-powder milks. In particular, the CLA contents were produced $183.57{\mu}g/ml$ and $198.72{\mu}g/ml$ from steamed soy-powder milk after fermentation (48 h) with S48 and P1201 strains, respectively.

• Korean Journal of Microbiology
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• v.47 no.3
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• pp.231-240
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• 2011

The objective of this study was to evaluate the acid and bile tolerance, bile salt hydrolase (BSH) activity, and cholesterol assimilation ability of lactic acid bacteria isolated from mustard leaf kimchi. MLK11, MLK22, MLK27, MLK41, and MLK67 were relatively acid- and bile-tolerant strains, with more than $10^5$ CFU/ml after incubation in simulated gastric juice and intestinal fluid, while MLK53 was the most sensitive strain to acid and bile. Strains MLK22 and MLK67 deconjugated the highest level of sodium glycocholate with more than 3.5 mM of cholic acid released, while deconjugation was lowest by strains MLK13 and MLK41 which released only 1.35 mM and 1.16 mM, respectively. Specially, strains MLK22 and MLK67 showed higher deconjugation of sodium glycocholate compared to sodium taurocholate and conjugated bile mixture. Although strains MLK22 and MLK67 exhibited maximal BSH activity at the stationary phase, MLK22 had somewhat higher total BSH activity compared to MLK67 towards both sodium glycocholate and sodium taurocholate. Meanwhile, cholesterol removal varied among tested strains (p<0.05) and ranged from 5.22 to 39.16 ${\mu}g$/ml. Especially, MLK67 strain assimilated the highest level of cholesterol in media supplemented with 0.3% oxgall, cholic acid, and taurocholic acid (p<0.05). According to physiological and biological characteristics, pattern of carbohydrate fermentation, and 16S rDNA sequence, strain MLK67 that may be considered as probiotic strain due to acid and bile tolerance and cholesterol-lowering effects was identified as Pediococcus pentosaceus MLK67.