• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.512-520
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• 2001

Kimchi is one of the traditional Korean food and a very popular side dish in Korea. To obtain funda mental data on how to prevent over ripening in kimchi after acidity of 0.4% was reached during the lactate fermentation, the physicochemical characteristics such as pH. acidity. organic acids, enzyme activity were measured and the time dependent ecology of microorganism were observed. In the initial stages of fermentation, the pH of kimchi was markedly changed and slowly decreased in 0.5% acidity The acidity was slowly increased and markedly increased in pH 4 by growth of microorganism. HPLC analysis showed oxalic acid, lactic acid, acetic acid, malic acid and succinic acid and this results reconfirmed by GC-MSD. Lactic acid was changed a lot during fermentation period as the time of storage went on, where as malic was decreased. Kimchi A, having acidity of 0.75%, showed the highest acidic Protease and lipase activity. Also, the amylase activity was high in kimchi C, having 0.95% acidity. The total viable bacteria showed 8.1$\times$10$^{5}$ , 4.7$\times$10$^4$, 1.2$\times$10$^3$, 3.2$\times$10$^4$, 4.9$\times$10$^{5}$ cfu/ml in the kimchi A, B, C, D and E, respectively. The numbers of lactic acid bacteria counted 1.0$\times$10$^{5}$ , 1.3$\times$10s, 1.2$\times$10$^3$, 2.3$\times$ 10$^3$, 2.1$\times$10$^4$c1u/m1 in the kimchi A, B, C, D and E, respectively. The numbers of acetobactor were counted 1.8$\times$10$^{5}$ , 9.3$\times$10$^4$, 7.0$\times$10$^1$, 4.5$\times$10$^4$, 5.3$\times$10$^3$cfu/m1 in the kimchi A, B, C, D and E, respectively.

• Korean Journal of Microbiology
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• v.50 no.1
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• pp.73-83
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• 2014

The objective of the this study was to investigate the binding capacity and removal ability of lactic acid bacterial strains obtained from Korean soybean paste for mutagenic heterocyclic amines (HCAs) formed during cooking of protein-rich food at high temperature. Among 19 strains identified by carbohydrate fermentation and 16S rRNA sequencing, the live cell or cell-free culture supernatant of Lactobacillus acidophilus D11, Enterococcus faecium D12, Pediococcus acidilactici D19, L. acidophilus D38, Lactobacillus sakei D44, Enterococcus faecalis D66, and Lactobacillus plantarum D70 inhibited the mutagenesis caused by either 3-amino-1,4-dimethyl-5H-pyrido[4,3-b] indole (Trp-P-1) or 3-amino-1-methyl-5H-pyrido[4,3-b] indole (Trp-P-2) in Salmonella typhimurium TA98 and TA100. The bacterial cells of the isolated strains showed greater binding activity than the pure cell wall, exopolysaccharide, and pepetidoglycan. The carbohydrate moieties of the cell wall or protein molecules on the cell surface have a significant role in binding Trp-P-1 and Trp-P-2, since protease, heating, sodium metaperiodate, or acidic pH treatments significantly (P<0.05) reduced the binding efficacy of the tested bacteria. Addition of metal ions or sodium dodecyl sulfate decreased the binding ability of E. faecium D12, L. acidophilus D38, and E. faecalis D66. Therefore, the binding mechanisms of these strains may consist of ion-exchange and hydrophobic bonds. Especially, the high mutagen binding by L. acidophilus D38 and L. plantarum D70 may reduce the accumulation or absorption of Trp-P-1 and Trp-P-2 in the small intestine via increased excretion of a mutagen-bacteria complex.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.17-23
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• 1987

Soy milk prepared from soy protein concentrate was fermented with each of the following lactic acid bacteria: Lactobacillus acidophilus KFCC 12731, L. acidophilus AKU 1122, L. bulgaricus, L. casei, Leuconostoc mesenteroides and Streptococcus lactis. The effects of methionine supple mented to soy milk on the growth and acid production by each organism. were investigated. L-methionine reduced the acid production by two strains of L. acidophilus while it had no apparent. effects on the other test cultures. The inhibitory effects of L-methionine on L. acidophilus KFCC 12731 was greater than on L. acidophilus AKU 1122. The acid production by L. acidophilus KFCC 12731 was also reduced substantially by DL-methionine supplemented to soy milk while it was not affected by D-methionine. Supplementation of L-cysteine to soy milk resulted in slight reduction of acid production by L. acido philus KFCC 12731.

• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.245-253
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• 2007

Artemisia princeps PAMPANINI has been used in traditional medicine of the treatment of inflammatory, liver dysfunction and order disorder in the far east countries including Korea. The present study was carried out to investigate the hepatoprotective effects of ethanol extract of Artemisia princeps (AP) and its fermented agents (AP-F) by lactic acid bacteria derived from human intestinal bacteria on liver injured rat induced by $CCl_4$ and d-galactosamine. Hepatoprotective activity was monitored by estimating serum ALT, AST, ALP, LDH, superoxide dismutase (SOD), glutathione redeuctase (GR) and glutathione peroxidase (Gpx) activities in the liver injured by hepatotoxin. Pretreating rats with AP or AP-F at the same dosage regimen significantly suppressed the acute elevation of serum transaminase, ALP, LDH and GR activities, and significantly increased the lowering of blood SOD and GR activites induced by hepatoxin. Based on these findings, it is presumed that AP and APF may have the hepatoprotective effect on $CCl_4$ and d-galactosamine-induced hepatotoxicity rat.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1510-1518
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• 2015

In this work, we wanted to develop a probiotic from famous longevity villages in Korea. We visited eight longevity villages in Korea to collect fecal samples from healthy adults who were aged above 80 years and had regular bowel movements, and isolated lactic-acid-producing bacteria from the samples. Isolated colonies that appeared on MRS agar containing bromophenol blue were identified by means of 16S rRNA sequencing, and 102 of the isolates were identified as lactic-acid-producing bacteria (18 species). Lactobacillus fermentum was the most frequently found species. Eight isolates were selected on the basis of their ability to inhibit the growth of six intestinal pathogens (Escherichia coli O157:H7, Salmonella enterica subsp. enterica Typhimurium, Salmonella enterica subsp. enterica Enteritidis, Enterococcus faecalis, Staphylococcus aureus, and Listeria monocytogenes) and their susceptibility to 15 antimicrobial agents. Among these eight isolates, four Lactobacillus fermentum isolates were found not to produce any harmful enzymes or metabolites. Among them, Lactobacillus fermentum isolate no. 24 showed the strongest binding to intestinal epithelial cells, the highest immune-enhancing activity, anti-inflammation activity, and anti-oxidation activity as well as the highest survival rates in the presence of artificial gastric juice and bile solution. This isolate, designated Lactobacillus fermentum PL9988, has all the characteristics for a good probiotic.

• Food Science of Animal Resources
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• v.33 no.3
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• pp.335-340
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• 2013

This study screened for radio-resistant strains lactic acid bacteria (LAB) by evaluating their capability to survive exposure to ionizing radiation. Ten strains of LAB - Lactobacillus bulgaricus, Lactobacillus paracasei, Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus delbruekii, Lactococcus lactis, Streptococcus thermophilus, Bifidobacterium breve, and Pediocuccos pentosaceus - were selected and subcultuted twice. The LAB was then further cultured for 3 d at $37^{\circ}C$ to reach 7-10 Log colony-forming units (CFU)/mL prior to irradiation and immediately exposed to gamma rays or electron beams with absorbed doses of 0, 1, 2, 3, 4, 5, 6, 8, and 10 kGy. Gamma irradiation gradually decreased the number of the tested viable LAB, and the effect was irradiation dose dependent. A similar effect was found in electron beam-irradiated LAB. Radiation sensitivity of LAB was calculated as $D_{10}$ values, which ranged from 0.26 kGy to 0.9 kGy and 0.5 kGy to 1.44 kGy with exposure to gamma and electron beam irradiation, respectively, in all tested LAB. L. acidophilus was the most resistant to gamma and electron beam irradiation, with $D_{10}$ values of 0.9 kGy and 1.44 kGy, respectively. These results suggest that L. acidophilus might be suitable for the preparation of probiotics as direct-fed microbes for astronauts in extreme space environments.

• Journal of Microbiology
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• v.44 no.4
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• pp.439-446
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• 2006

In this study, the growth kinetics of Lactobacillus rhamnosus and lactic acid production in continuous culture were assessed at a range of dilution rates $(0.05 h^{-1}\;to\;0.40h^{-1})$ using a 2L stirred tank fermenter with a working volume of 600ml. Unstructured models, predicated on the Monod and Luedeking-Piret equations, were employed to simulate the growth of the bacterium, glucose consumption, and lactic acid production at different dilution rates in continuous cultures. The maximum specific growth rate of L. rhamnosus, ${\mu}_{max}$, was estimated at $0.40h^{-1}$I, and the Monod cell growth saturation constant, Ks, at approximately 0.25g/L. Maximum cell viability $(1.3{\times}10^{10}CFU/ml)$ was achieved in the dilution rate range of $D=0.28h^{-1}\;to\;0.35h^{-1}$. Both maximum viable cell yield and productivity were achieved at $D=0.35h^{-1}$. The continuous cultivation of L. rhamnosus at $D=0.35h^{-1}$ resulted in substantial improvements in cell productivity, of 267% (viable cell count) that achieved via batch cultivation.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.443-448
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• 2010

Casein phosphopeptide (CPP) enhances calcium absorption in humans. Lactic acid bacteria (LAB) are capable of synthesis of cell-surface proteinase, which can hydrolyze milk protein and release several types of peptides in the medium. This study was conducted to characterize proteinase of LAB and to evaluate the CPP production from bovine milk. The content of CPP of milk produced by cell-free extract of LAB was determined based on the quantity of decomposed peptide from casein using the O-phthaldialdehyde (OPA) method. The proteolytic activity of LAB was assayed using fluorescein isothiocyanate (FITC)-labeled casein. Casein appeared to be a better substrate than whey proteins for extracellular proteinases of LAB. During fermentation, milk proteins were hydrolyzed by extracellular proteinase of LAB, resulting in an increase in the amount of free $NH_3$ groups. Overall, the results presented here indicate that CPP produced by LAB may be a promising material for novel applications in the dairy industry.

• Food Science of Animal Resources
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• v.35 no.4
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• pp.541-550
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• 2015

The purpose of this study was to investigate the effect of lactic acid bacteria (LAB) cell wall extract on the proliferation and cytokine production of immune cells to select suitable probiotics for space food. Ten strains of LAB (Lactobacillus bulgaricus, L. paracasei, L. casei, L. acidophilus, L. plantarum, L. delbruekii, Lactococcus lactis, Streptococcus thermophilus, Bifidobacterium breve, and Pedicoccus pentosaceus) were sub-cultured and further cultured for 3 d to reach 7-10 Log colony-forming units (CFU)/mL prior to cell wall extractions. All LAB cell wall extracts failed to inhibit the proliferation of BALB/c mouse splenocytes or mesenteric lymphocytes. Most LAB cell wall extracts except those of L. plantarum and L. delbrueckii induced the proliferation of both immune cells at tested concentrations. In addition, the production of T_H1 cytokine (IFN-γ) rather than that of T_H2 cytokine (IL-4) was enhanced by LAB cell wall extracts. Of ten LAB extracts, four (from L. acidophilus, L. bulgaricus, L. casei, and S. thermophiles) promoted both cell proliferating and T_H1 cytokine production. These results suggested that these LAB could be used as probiotics to maintain immunity and homeostasis for astronauts in extreme space environment and for general people in normal life.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.229-234
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• 1997

Shizandra chinensis(SC) and Pinus regida(PR) showed antimicrobial activity against 3 strains(B-5, D-1, A-1) of lactic acid bacteria(LAB) isolated from kimchi among eight kinds of plant extracts such as Shizandra chinensis, Phellodendron amurense, ornus officinalis, Pinus regida, Allium tuberosum, Machilus thunbergii, Cyperus rotundus and Schizonepeta tenuifloia. The growth of LAB was inhibited apparently in modified MRS broth containing 1% Schizandra chinensis at $35^{\circ}C$. Pinus regida showed weaker inhibitory effect on the growth of isolated LAB than Shizandra chinensis. pH of SC added kimchi did not change greatly compare with control during 25 days of fermentation. Degree of titratable acidity change and ratio of reducing sugar utilization in control were more higher than in SC added kimchi during fermentation. Growth of total bacteria and lactic acid bacteria was inhibited about 1 to 2 $log_10$ cycle by addition of SC extracts during kimchi fermentation for 10 days at $10^{\circ}C$. Fermentation of kimchi was delaved about 5 to 7 days by addition of 1 or 2% of SC. extract, but sensory quality (falvor, taste and overall acceptability) of SC added kimchi was lower than that of control (p>0.05).