• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.990-997
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• 1995

Effect of preparation method on Yulmoo kimchi(watery kimchi prepared with Yulmoo, leaf radish) fermentation was investigated by measuring physicochemical, microbiological and sensory properties for 20 days. Yulmoo kimchi was fermented at 4$^{\circ}C$ after keeping at room temperature(27$\pm$0.5$^{\circ}C$) for 8 hours. Four types(A, B, C, D) of Yulmoo kimchi were prepared. Sample A was made without wheat flour paste and red pepper powder and sample B was made with wheat flour paste. Sample C was made with red pepper powder, and sample D was made with wheat flour paste and red pepper powder. pH was slowly lowered and stabled after 10 days in all samples. Total acid content increased in all samples. Reducing sugar content initially increased and decreased thereafter. Especially, reducing sugar content of sample B increased in the early stage of fermentation and maintained initial reducing sugar content after 20 days. Total vitamin C content reduced during fermentation in all samples. Especially initial total vitamin C content of sample D increased more than those of other samples relatiely. Lightness and yellowness showed no difference, but on the other hand redness increased gradually in all samples. The number of lactic acid bactgeria reached maximum value in 10~13 days with the total cell numbers and gradually decreased thereafter in all samples. The number of lactic acid bacteria and total cell number of sample D was much more than those of any other samples. As a result of the sensory evaluation, Yulmoo kimchi showed significant difference in all characteristics. Sample D showed the highest scores in all characteristics before 10 days of fermentation. However, after 10 days sample B showed the highest scores.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.619-625
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• 2005

The present study was undertaken to investigate the hypoglycemic effect of Hamcho yogurt fermented by lactic acid bacteria containing Hamcho (Salicornia herbacea) extract powder in streptozotocin(STZ)-induced diabetic rats for 3 week period. The Hamcho yogurt given to the STZ-diabetic rats had significant effect in lowering the serum glucose concentrations and food intakes compared to the STZ-diabetic rats. The Hamcho yogurt administration increased the tolerance to oral glucose loading in the STZ-diabetic rats. The Hamcho yogurt and yogurt given to the STZ-diabetic rats were significantly decreased the serum total cholesterol concentration and the atherogenic index. Based on the beneficial effect against the blood glucose and cholesterol levels, we suggest the Hamcho yogurt can be used as functional food for the hypoglycemic and hypocholesterolemic effects.

• Journal of Microbiology and Biotechnology
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• v.27 no.9
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• pp.1586-1592
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• 2017

Some promoters were isolated and characterized from the genome of Leuconostoc mesenteroides SY2, an isolate from kimchi, a Korean traditional fermented vegetable. Chromosomal DNA of L. mesenteroides SY2 was digested with Sau3AI and ligated with BamHI-cut pBV5030, a promoter screening vector containing a promoterless cat-86. Among E. coli transformants (TFs) resistant against Cm (chloramphenicol), 17 were able to grow in the presence of $1,000{\mu}g/ml$ Cm and their inserts were sequenced. Transcription start sites were examined for three putative promoters (P04C, P25C, and P33C) by primer extension. Four putative promoters were inserted upstream of a promoterless ${\alpha}$-amylase reporter gene in $pJY15{\alpha}$. ${\alpha}$-Amylase activities of E. coli TFs containing $pJY15{\alpha}$ (control, no promoter), $pJY03{\alpha}$ ($pJY15{\alpha}$ with P03C), $pJY04{\alpha}$ (with P04C), $pJY25{\alpha}$ (with P25C), and $pJY33{\alpha}$ (with P33C) were 66.9, 78.7, 122.1, 70.8, and 99.3 U, respectively. Cells harboring $pJY04{\alpha}$ showed 1.8 times higher activity than the control. Some promoters characterized in this study might be useful for construction of food-grade expression vectors for Leuconostoc sp. and related lactic acid bacteria.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.543-547
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• 2007

Bovine mastitis is costly infectious disease of dairy cattle, being responsible for significant economic losses all over the world. Also, mastitis has troubled about resistance to antibiotics. The purpose of this study was to screen a novel antimicrobial strain from various sources (raw milk and feeds (from farm of Paju, Dangjin, and Hwasung), commercial milk, Korean traditional fermented foods, and chicken feces). The isolate was screened using triple agar layer method and deferred method was used for confirmation of antimicrobial effect. Seventy six of isolates were screened using triple agar layer method. In these strain, 42 isolates were shown a broad spectrum of autimicrobial activity against mastitis pathogens. Especially, fourteen isolates were shown over 20 mm inhibition zone against S. aureous ATCC 25923. These results suggest that these novel antimicrobial strains could be used for the alternative of antibiotics.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.811-816
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• 1998

A fermented vegetable kimchi swells in package bags often during distribution to comsumer after storage. The swelling has been prohibited by packaging the kimchi in a modified LDPE film that has been made by filling a ceramic powders disinfecting to lactic acid bacteria and growth enhancing to vegetables. The film exhibited higher permeability to carbon dioxide and ethylene than LDPE film. The tastes of kimchi in the film sustained its optical quality longer than that in LDPE film at room temperature.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.800-806
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• 2008

The strain HK-12 was enriched and isolated from naturally fermented soybean for the production of fibrinolytic enzyme and the proteome of this enzyme induced during the incubation period was analyzed. The activity of fibrinolytic enzyme derived from supernatants of the HK-12 culture was performed by fibrin plate method for solid fibrinolytic activity. As the result, the fibrinolytic activity of HK-12 grown on the nutrient agar media was about 2.3 times greater than that of plasmin used as standard. The purified enzyme was prepared by a series of purification process including ammonium sulfate precipitation, DEAE-cellulose, Sephadex chromatography. The molecular weight of the enzyme was determined to approximately 23kDa with SDS-PAGE. In order to examine which strain HK-12 proteins increased or decreased during the incubation period, 2-DE analysis was performed. Protein spot #1 significantly expressed on the 2-DE gel of bacteria cultivated for 36-hrs was analysed. As the result of protein sequence analysis using MALDI-TOF MS, one protein was identified as serine protein kinase (PrkA).

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.822-831
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• 2000

Application of omija(Schizndra chinensis Baillon) to improve the quality and preservation of nabka kimchi was attempted and the optimal amount of omija level and its effect on the sensory and microbiological properties of nab마 kimchi during fermentation were examined. Effects of omija juice which had been prepared by extracting omija seeds for 9 hr at room temperature (22.5$\pm$0.5$^{\circ}C$) with different ratios (0.5, 1.0, 1.5, 2.0%;w/v) of water were examined against control (kimchi prepared without omija). Organoleptic and microbiological properties of nabak kimchi were measured up to 25 days at 1$0^{\circ}C$ after preparation. Sensory properties were evaluated in the aspects of both acceptability and intensity characteristics. In whole, 0.5 and 1.0% treatments showed higher values of evaluation, compared to control, 1.5, and 2.0% treatments throughout the fermentation period. As fermentation progresses, however, sample of 1.0% treatment ranked first between day 4 to 7 and also so did sample of 0.5% treatment along with 1.0% treatment from behind day 10. As for color, control, 0.5% treatment, and 1.0% treatment were more favored than rest of the samples. In texture, 2.0% treatment showed the highest values, whereas control was rated the lowest. In the intensity of characteristics 1.5% and 2.0% treatments showed higher values except sweet taste in which 1.0% treatment ranked top during the initial 7 days and then 0.5% treatment took the first place at behind day 10. total cell counts and number of lactic acid bacteria were gradually increased and then decreased showing the maximum levels of microbial counts on different days, to say, day 2 for control and 0.5% treatment nd day 7 for 1.0, 1.5 and 2.0% treatments. The application of omija juice in nabak kimchi enhanced eating qualities of the fermented product and the fermentation-retarding effect of omija juice was clearly shown during the initial seven days of fermentation. The optimum levels of omija juice in nabak kimchi obtained through experiments were between 0.5 to 1.0% for color, fermentation-retarding effects, and savory taste of the product.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.1
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• pp.103-109
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• 2019

Objective: Ensiling of tannin-rich fruit byproducts (FB) involves quantitative and qualitative changes in the tannins, which would consequently change the rumen fermentation characteristics. This study aimed to evaluate whether ensiled FBs are effective in mitigating methane emission from ruminants by conducting in vitro assessments. Methods: Fruit byproducts (grape pomace, wild grape pomace, and persimmon skin) were collected and subjected to four-week ensiling by Lactobacillus buchneri inoculant. A defined feed component with or without FB samples (both fresh and ensiled material) were subjected to in vitro anaerobic culturing using rumen fluid sampled from beef cattle, and the fermentation parameters and microbial populations were monitored. Results: Reduced methane production and a proportional change in total volatile fatty acids (especially enhanced propionate proportion) was noted in bottles containing the FBs compared with that in the control (without FB). In addition, we found lower gene copy number of archaeal 16S rRNA and considerably higher levels of one of the major fibrolytic bacteria (Fibrobacter succinogenes) in the bottles containing FBs than in the control, particularly, when it was included in a forage-based feed. However, in the following cultivation experiment, we observed that FBs failed to exhibit a significant difference in methane production with or without polyethylene glycol, implying that tannins in the FBs may not be responsible for the mitigation of methane generation. Conclusion: The results of the in vitro cultivation experiments indicated that not only the composition but also ensiling of FBs affected rumen fermentation patterns and the degree of methane generation. This is primarily because of the compositional changes in the fibrous fraction during ensiling as well as the presence of readily fermented substrates, whereas tannins in these FBs seemed to have little effect on the ruminal fermentation kinetics.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.548-557
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• 2019

Staphylococcus species have a ubiquitous habitat in a wide range of foods, thus the ability to identify staphylococci at the species level is critical in the food industry. In this study, we performed rapid identification of Staphylococcus species using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS was evaluated for the identification of Staphylococcus reference strains (n = 19) and isolates (n = 96) from various foods with consideration for the impact of sample preparation methods and incubation period. Additionally, the spectra of isolated Staphylococcus strains were analyzed using principal component analysis (PCA) and a main spectra profile (MSP)-based dendrogram. MALDI-TOF MS accurately identified Staphylococcus reference strains and isolated strains: the highest performance was by the EX method (83.3~89.5% accuracy) at species level identification (EDT, 70.3~78.9% accuracy; DT, less than 46.3~63.2% accuracy) of 24-h cultured colonies. Identification results at the genus level were 100% accurate at EDT, EX sample preparation and 24-h incubation time. On the other hand, the DT method showed relatively low identification accuracy in all extraction methods and incubation times. The analyzed spectra and MSP-based dendrogram showed that the isolated Staphylococcus strains were characterized at the species level. The performance analysis of MALDI-TOF MS shows the method has the potential ability to discriminate between Staphylococcus species from foods in Korea. This study provides valuable information that MALDI-TOF MS can be applied to monitor microbial populations and pathogenic bacteria in the food industry thereby contributing to food safety.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.10
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• pp.1580-1590
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• 2019

Objective: The aims of this study were to select one strain of Lactobacillus plantarum (L. plantarum) for a potential indigenous safe starter culture with low level antibiotic resistant and low biogenic amine production and evaluate its effect on biogenic amines reduction in Moo som. Methods: Three strains of indigenous L. plantarum starter culture (KL101, KL102, and KL103) were selected based on their safety including antibiotic resistance and decarboxylase activity, and fermentation property as compared with a commercial starter culture (L. plantarum TISIR543). Subsequently, the effect of the selected indigenous safe starter culture on biogenic amines formation during Moo som fermentation was studied. Results: KL102 and TISIR 543 were susceptible to penicillin G, tetracycline, chloramphenicol, erythromycin, gentamycin, streptomycin, vancomycin, ciprofloxacin and trimethoprim (MIC90 ranging from 0.25 to $4{\mu}g/mL$). All strains were negative amino acid-decarboxylase for lysis of biogenic amines in screening medium. For fermentation in Moo som broth, a relatively high maximum growth rate of KL102 and TISIR543 resulted in a generation time than in the other strains (p<0.05). These strain counts were constant during the end of fermentation. Similarly, KL102 or TISIR543 addition supported increases of lactic acid bacterial count and total acidity in Moo som fermentation. For biogenic amine reduction, tyramine, putrescine, histamine and spermine contents in Moo som decreased significantly by the addition KL102 during 1 d of fermentation (p<0.05). In final product, histamine, spermine and tryptamine contents in Moo som inoculated with KL102 were lower amount those with TISIR543 (p<0.05). Conclusion: KL102 was a suitable starter culture to reduce the biogenic amine formation in Moo som.