• Korean Journal of Microbiology
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• v.37 no.3
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• pp.234-238
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• 2001

For the comparison of fermentation pattern of leek kimci with chinese cabbage kimchi, the changes of total viable cell number, Leuconostoc sp. bacteria, Lactobacillus sp. bacteria, pH and total sugar content of twotypes kimchies were investigated during fermentation at $20^{\circ}C$ and $10^{\circ}C$. In chinese cabbage kimchi at $20^{\circ}C$ fermentaion, the numbers of total viable cell, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria reachedthe maximum level on 2nd day and reduced slowly. But in leek kimchi, the maximum numbers of total via-ble cells, Leuconostoc sp. bacteria and Lactobacillus sp. bacteria were obtained after 3 days fermentation,and the cell number of Lactobacillus sp. maintained at the maximum level oyer 15 days. At $10^{\circ}C$ fer-mentation, in both kimchies, the viable cell number of lactic acid bacteria more slowly increased anddecreased than at $20^{\circ}C$. The pH of chinese cabbage kimchi was 4.2 on 3rd day (optimal ripening phase) andmere decreased to 3.5 after 5 days, but in leek kimci the pH 4.2 could be reached after 10 days at $20^{\circ}C$. At $10^{\circ}C$, the optimal ripening pH 4.2 of chinese cabbage kimchi was reached after 6 days, but in leek kimchieven though after 24 days, the pH was maintained oyer 4.3. The total sugar contents of chinese cabbage him-chi and leek kimci were decreased continuously during fermentation. From these results, we know that thefermentation of leek kimchi proceed more slowly than chinese cabbage kimchi by the retardation of lacticacid bacteria growing in leek kimchi.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.277-282
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• 1999

This study was carried out to clarify the microorganisms which participated in the fermentation of kanjang. The changes in the viable cell counts of total aerobic bacteria, lactic acid bacteria and yeasts for raw soybean, soybean during cooking, meju during cultivation, and kanjang mash during maturing were investigated along with the changes in components during those periods. Lactic acid bacteria that were found to be $6{\times}10^2\;CFU/g$ in raw soybean were disappeared after cooking process, but total aerobic bacteria were diminished from $1.9{\times}10^6\;CFU/g$ to $10^2\;CFU/g$. Aerobic bacteria of inner and outer parts of meju increased to more than $10^9\;CFU/g$. The higher viable cell counts of lactic acid bacteria in the inner parts of meju were observed than those in outer ones. On the contrary, significantly higher viable cell counts of yeasts in the outer parts of meju were found. Total nitrogen content and color density of kanjang increased by using meju with extended cultivation periods. No significant differences were observed in microbial counts between kanjang mash with aeration and non-aeration during kanajng mash maturing.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.138-143
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• 2004

Soybean curd residues (SCR) obtained from hot and cold manufacturing processes were fermented by indigenous microorganisms, Lactobacillus rhamnosus LS and Bacillus firmus NA-l for 15 h at 37$^{\circ}C$. The pH, acidity, viable cell counts, and tyrosine content were evaluated in samples with variations in sugar, starter and type of SCR. The raw Doowon SCR (D-SCR, cold-processed) fermented by indigenous microorganism had a 0.9% acidity and 6.7 ${\times}$ 10$^{7}$ CFU/g viable cell counts, compared with the 0.11 % acidity and 6.7 ${\times}$ 10$^{6}$ CFU/g viable cell counts of raw fermented Pulmuwon SCR (P-SCR, hot-processed). After fermentation of raw P-SCR with 1 % glucose and 1 % L. rhamnosus LS starter, the viable cell counts, tyrosine content and acidity were 4.7 ${\times}$ 10$^{8}$ CFU/g, 16.3 mg% and 0.9%, respectively. In addition, the raw P-SCR fermented with Bacillus firmus NA-l as co-starter had a 0.45% acidity, 2.4 ${\times}$ 10$^{8}$ CFU/g lactic acid bacteria, and 3.3 ${\times}$ 10$^{6}$ CFU/g Bacillus sp. In particular, the tyrosine content was increased 5 fold. The drying of fermented SCR was completed by hot-air drying (5$0^{\circ}C$) within 12 h; the dried P-SCR and D-SCR had 1.8 ${\times}$ 10$^{7}$ CFU/g and 5.3 ${\times}$ 10$^{6}$ CFU/g viable cell counts, respectively. The concentrate of methanol extract from fermented D-SCR inhibited the initial cell growth of E. coli, Staphylococcus aureus and Pseudomonas aeruginosa in liquid culture.

• The Korean Journal of Food And Nutrition
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• v.15 no.1
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• pp.42-50
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• 2002

This experiment was carried out to investigate the effect of Maesil extract on the acid production and growth of yoghurt starter in the skim milk medium. The Maesil extract was added to skim milk medium fur 1% to 9% and the medium was fermented by single or mixed culture of 4 types of lactic acid bacteria(Streptococcus thermophilus, Lactobacillus acidophilus, Lactobacillus, bulgaricus, Lactobacillus casei). The chemical composition of Maesil, the changes in acid production (titratable acidity, pH) and number of viable cells of the medium during lactic fermentation in skim milk added with Maesil extract, and the keeping quality of curd yoghurts containing Maesil extract have determined. The composition of Maesil were 0.4% crude ash, 4.1% dietary fiber, 4.66%l citric acid, 0.264% total sugars and 405.34mg% vitamin C. The addition of Maesil extract stimulated the acid production and propagation of the lactic acid bacteria. Among the treatments tested, the addition of 3% Maesil extract with the mixed culture of Streptococcus thermophilus, Lactobacillus acidophilus and Lactobacillus casei produced the highest amount of acid(1.23%) and showed the highest number of viable cell counts(3.6$\times$10$^{11}$ cfu/mL). When the curd yoghurts containing 3% Maesil extract with the mixed culture of the lactic acid bacteria were kept at 4$^{\circ}C$ and 2$0^{\circ}C$ for 30 days, it was showed that the changes of titratable acidity, pH and number of viable cell counts of the lactic acid bacteria were not significantly different during storage. Therefore the keeping quality of the curd yoghurts adding 3% Maesil extract showed relatively good at the shelf-life.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.2
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• pp.131-134
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• 2004

This study was carried out to investigate the shelf life of Shepherd's purse(Capsella bursa-pastoris) Kimchi during fermentation at 1$0^{\circ}C$. Capsella bursa-pastoris was treated without or with blanching. The viable cells of lactic acid bacteria(LAB) of raw and blanched Kimchi after fermentation for 15 days at 1$0^{\circ}C$ were 7.91 log CFU/mL and 6.4 log CFU/mL, respectively. The viable cells of LAB of Capsella bursa-pastoris Kimchi at 1$0^{\circ}C$ were lower in the blanched one when compared to the raw one. The pH of raw Kimchi was lower than that of the blanched one during fermentation for 25 days at 1$0^{\circ}C$. The viable cells of total bacteria of the blanched Kimchi were lower than that of non-blanched one during fermentation at 1$0^{\circ}C$. The ascorbic acid and chlorophyll contents decreased more in the blanched Kimchi when compared to that treated without heat. The sensory quality of the blanched Kimchi was a little inferior to that treated without heat during fermentation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.6
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• pp.696-701
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• 2013

Flounder Verasper moseri Jordan et Gilberu sikhae is one of the traditional Korean fermented food. Microbiological, chemical, and biogenic amine analyses were carried out to evaluate the quality of commercial flounder sikhae and establish standardization. The quality characteristics were analyzed in terms the salinity, volatile basic nitrogen, pH, amino-N, TBA value, biogenic amine, viable cell count, and lactic acid bacteria. Quality evaluation of commercial flounder sikhae revaled an average pH of 4.84, volatile basic nitrogen of 43.47 mg/100 g, amino-N of 213.04 mg/100 g, salinity of 5.77 %, viable cell count of $10^6-10^7CFU/g$, viable lactic acid bacteria count of $10^6-10^7CFU/g$ and biogenic amine level of 0.70-47.34 mg/kg.

• Microbiology and Biotechnology Letters
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• v.24 no.2
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• pp.247-253
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• 1996

Changes in microorganisms, enzyme activities and major components of two types of Doenjang prepared with spring Meju and autumn Meju and Kochujang were investigated during 4 months of fermentation. The viable cell counts of aerobic bacteria in Doenjang and Kochujang were increased up to 60 days of fermentation, but viable cell counts of anaerobic bacteria did not show remarkable changes during fermentation. Viable cell count of yeast showed a rapid increase up to 15 days of fermentation in Doenjang and 60 days in Kochujang. It was found that $\alpha$-amylase activity of autumn Meju Doenjang and glucoamylase activity of Kochujang were higher than the other. Acidic and neutral protease showed the highest activity during 15-30 days of fermentation. The pH of Doenjang was increased up to pH 7.0 until 60 days of fermentation, but pH of Kochujang gradually decreased during fermentation. Moisture content of spring Meju Doenjang and Kochujang decreased to 40% during ferme- ntation and reducing sugar content of Kochujang increased up to 15 days of fermentation, but decreased after that.

• Journal of Microbiology
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• v.43 no.spc1
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• pp.93-100
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• 2005

It had long been assumed that a bacterial cell was dead when it was no longer able to grow on routine culture media. We now know that this assumption is simplistic, and that there are many situations where a cell loses culturability but remains viable and potentially able to regrow. This mini-review defines what the 'viable but nonculturable' (VBNC) state is, and illustrates the methods that can be used to show that a bacterial cell is in this physiological state. The diverse environmental factors which induce this state, and the variety of bacteria which have been shown to enter into the VBNC state, are listed. In recent years, a great amount of research has revealed what occurs in cells as they enter and exist in this state, and these studies are also detailed. The ability of cells to resuscitate from the VBNC state and return to an actively metabolizing and culturable form is described, as well as the ability of these cells to retain virulence. Finally, the question of why cells become nonculturable is addressed. It is hoped that this mini-review will encourage researchers to consider this survival state in their studies as an alternative to the conclusion that a lack of culturability indicates the cells they are examining are dead.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.221-225
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• 1998

Fourteen healthy volunteers ranged in ages from 20 to 30 were served to administrate two types of yoghurt (2 bottles/day) such as one added uncapsulated-Bifidobacteria (Y-UCB) and the other added capsulated-Bifdobacteria (Y-CB) for 4 weeks, and the changes of intestinal microflora and fecal properties were studied. After administration of Y-UCB, the viable cell counts of fecal Bifidobacteria (p<0.01) and Lactobacilli (p<0.05) were significantly increased, however, fecal pH, moisture content and tile viable cell counts of coliform bacteria in feces were not changed when they were compared to those before administration (control). After administration of Y-CB, the viable cell counts of Bifidobacteria were significantly increased (p<0.01) and viable cell counts of coliform bacteria were significantly decreased (p<0.05), however, fecal pH, moisture content, and viable cell counts of Lactobacilli were not changed when they were compared to those before administration. High level of fecal Bifidobacteria and low pH were maintained after 2 weeks from ceasing the administration of both types of yoghurt when they were compared to those before administration. In conclusion, there were not significant differences between two types, Y-CB and Y-UCB in the changes of fecal pH, moisture content, and the viable cell counts of Bifidobacteria, Lactobacilli, coliform bacteria after the administration.

• Microbiology and Biotechnology Letters
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• v.40 no.2
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• pp.111-116
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• 2012

In this study, we investigated the microbial flora changes in Gugija-Liriope tuber Makgeolli during fermentation and storage periods. We brewed Gugija-Liriope tuber Makgeolli for a week through twostage fermentations and stored the fermentation broth for a month at $4^{\circ}C$ or $20^{\circ}C$. We collected the samples periodically and analyzed microbial flora changes using viable cell counts and PCR-denaturing gradient gel electrophoresis (DGGE). Yeast viable cells were seen to have decreased to 13% of pre-storage levels after storage for 15 days at $20^{\circ}C$; however significant changes were not observed during storage at $4^{\circ}C$. Prolongation of storage time dramatically decreased the availability of viable cells. Yeast viable cell numbers had decreased to 38% of pre-storage levels at $4^{\circ}C$ and 4.8% at $20^{\circ}C$ after storage for 30 days. The results of the DGGE profile for yeast showed that Saccharomyces cerevisiae and Saccharomyces sp. were the predominant strains at the beginning of fermentation and throughout the whole period of storage. Viable cell counts for total bacteria had decreased to 36% of pre-storage levels after storage for 15 days but did not significantly change for the full 30 days of storage at $4^{\circ}C$. Similarly, viable cell counts for bacteria had decreased to 5% while viable cell numbers did not significantly change for the full 30 days at $20^{\circ}C$. Viable cell counts for lactic acid bacteria were performed and the results were similar to those for total bacteria. The results of the DGGE profile for bacteria showed that Weissella cibaria was the predominant strain at the beginning of fermentation. However it had disappeared by the end of fermentation, and Lactobacillus fermentum and Pediococcus acidilactici became the predominant species during storage.