• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.515-520
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• 2013

Bacterial communities derived from cheonggukjang and raw rice straw collected from a Mireuksan farm and a Heungup cheonggukjang in Gangwon province were investigated using both culture-based method and denaturing gradient gel electrophoresis (DGGE) analysis. Pure cultures, which were isolated from raw rice straw and cheonggukjang and cultured on tryptic soy agar plates (53-76 colonies per plate), were identified by analysis of 16S rRNA sequences. The traditional culture-based method and analysis of PCR-amplified 16S rRNA by DGGE revealed that for samples collected from the Mireuksan farm, Pantoea agglomerans and Bacillus subtilis were the predominant species in the raw rice-straw and cheonggukjang, respectively. For samples collected from the Heungup cheonggukjang, Bacillus amyloliquefaciens was the predominant species in both raw rice straw and cheonggukjang. Other microorganisms, including members of Pantoea, Bacillus, Enterococcus, Enterobacter, Pseudomonas, Rhodococcus, and Acinetobacter, were also present in the raw rice-straw and cheonggukjang, as were bacteria that could not be cultured.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.241-249
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• 2002

In this research, we targeted to see if there was difference of shelf$.$lives of two different species cucumber. We pickled domestic and exporting cucumber to make comparison while they were fermented and stored. As for the domestic cucumber we choose CHICHEONG and for the exporting cucumber we choose special BAEKSEONG and SHARP 1. We blanched them and soaked them into hot saline water for 8 hours. Two kinds of Cucumber Kimchi were at room temperature for first day and 5'c from 2nd to 28th day. It was found, from the results, that all of samples of pH reached at 3.5 $\pm$ 0.1 on the 14th day of fermentation. The titratable acidity of the control increased on 14th day of fermentation, which was bit late than change of others. The reducing sugar contents of the control did not decrease until 7th day of fermentation while reducing sugar contents of others decreased gradually from the beginning. The patterns of Microfloral changes of two kinds of Cucumber Kimchi were similar during fermentation period. The number of total cell increased up to 14th day, similary the numbers of lactic acid bacteria increased up to 14th day then barely decreased. The hardness of the control was bit higher than others when it was measured on 14th day of fermentation. The sensory evaluation of Cucumber Kimchi with different species showed that both species had siginificant high negative scores in green color and crispness when those were compared between fermentation time and samples.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1026-1032
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• 2015

This study attempted to find an efficient method for the preparation of high-purity galactooligosaccharides (HP-GOS) using ${\beta}$-galactosidase and yeast fermentation. GOS prepared using Lactozym 3000L showed the greatest enhancement in total GOS of the six ${\beta}$-galatosidases tested. GOS alone achieved 51% conversion of initial lactose. GOS production was enhanced by fermentation with commercial yeast (Saccharomyces cerevisiae); its concentration reached 71% after 36h fermentation with 8% yeast. Component sugar analysis with HPLC indicated that HP-GOS fermented with S. cerevisiae showed significantly increased levels of 4'/6'-galactosyllactose and total GOS as well as a significantly decreased glucose level. HP-GOS facilitated the growth of Lactobacillus sp. (L. acidophilus and L. casei) and Bifidobacterium sp. (B. longum and B. bifidum). In sum, high-purity GOS has been successfully produced through both an enzymatic process and yeast fermentation. GOS encourages the growth of bacteria such as Lactobacillus and Bifidobacterium that may be beneficial to human gastrointestinal health.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.495-501
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• 1999

Lactobacillus acidophilus KY 2104 was isolated from 41 healthy korean ($2{\sim}35\;age$, 26 man, 15 woman) feces to use as a probiotic lactic acid bacteria for functional foods, fermented milk and pharmaceutical products. L. acidophilus KY 2104 survived in the presence of acid and bile, and inhibited pathogens. It survived almost 100% in pH 3.0 phosphate buffer for 2 hr, and more than $10^4\;cfu/mL$ in pH 2.0 phosphate buffer when inoculated by $10^7\;cfu/mL$. It was also found to grow in MRS medium containing 0.5% oxgall. L. acidophilus KY 2104 exerted inhibitory effect against enteric pathogens such as Escherichia coli, Shigella dysenteriae, Staphylococcus aureus and Salmonella typhimurium, when grown with each in associative cultures for 16 hr. As a result of acute toxicity of L. acidophilus KY 2104 in rats, there was no observation on motality, clinical signs, body weights and gross findings in the oral administration.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.8
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• pp.1292-1300
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• 2020

Objective: To explore feed resources capable of replacing regular poor-quality fodder, this study was conducted to evaluate the effects of additives on the fermentation quality, in vitro digestibility and aerobic stability of mulberry leaves silage. Methods: The mulberry leaves were ensiled either untreated (control) or treated with 1×10⁶ cfu/g fresh matter Lactobacillus plantarum (L), 1% glucose (G), 3% molasses (M), a combination of 1% glucose and Lactobacillus plantarum (L+G), and a combination of 3% molasses and Lactobacillus plantarum (L+M). The fermentation quality and chemical composition were analyzed after 7, 14, 30, and 60 d, respectively. The 60-d silages were subjected to an aerobic stability test and fermented with buffered rumen fluid to measure the digestibility. Results: Inoculating lactic acid bacteria (LAB) resulted in more rapid increase in lactic acid concentrations and decline in pH of mulberry leaves silage as compared control. Higher acetic acid and lower ethanol and ammonia nitrogen concentrations (p<0.05) were observed in the LAB-inoculated silages as opposed to control during ensiling. The LAB-inoculated silages contained lower water-soluble carbohydrates compared with control during the first 14 d of ensiling, and lower neutral detergent fibre (p<0.05) concentrations as compared with non-LAB inoculated silages. Adding molasses alone increased (p<0.05) the digestibility of dry matter (DM). The aerobic stability of mulberry leaves silage was increased by LAB inoculation, whereas decreased by adding glucose or molasses. Conclusion: The LAB inoculation improved fermentation quality and aerobic stability of mulberry leaves silage, while adding glucose or molasses failed to affect the fermentation and impaired the aerobic stability. Inoculating LAB alone is recommended for mulberry leaves especially when ensiled at a relatively high DM.

• Food Science and Preservation
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• v.23 no.6
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• pp.883-889
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• 2016

A new lactic acid bacteria with gluten-degrading activity which was isolated from salted sea foods (traditional Korea fermented food), identified as Weissella confusa (99%) by use of API kit and 16S rRNA sequencing, and designated as W. confusa. When the W. confusa cultured for 48 hours at $30^{\circ}C$ in a MRS medium containing 1% gluten, 45% of gluten was founded to be degraded. W. confusa showed 85% of survival rate at pH 3, and 94% tolerance at 0.1% oxgall, which indicates that W. confusa would survive in stomach of human. Experiments on the thermostability was confirmed that it has a stability of 70% in $50^{\circ}C$. W. confusa inhibited the growth of some pathogen, except for S. aureus. Results in this study suggest that using W. confusa for fermentation of grain flour containing gluten would be desirable to prepare the gluten-free foods needed for those who suffer from celia disease and gluten allergy.

• Journal of Life Science
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• v.26 no.10
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• pp.1113-1120
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• 2016

Two bacterial strains producing extracellular man nanase were isolated from doenjang, a traditionally fermented soybean paste in Korea. The isolates, WL-6 and WL-11, were identified as Bacillus subtiis on the basis of their 16S rRNA gene sequences, morphological, and biochemical properties. Two genes encoding the mannanase of both B. subtilis WL-6 and B. subtilis WL-11 were each cloned into Escherichia coli, and their nucleotide sequences were determined. Both mannanase genes consisted of 1,086 nucleotides, encoding polypeptides of 362 amino acid residues. The deduced amino acid sequences of the two WL-6 and WL-11 mannanases, designated Man6 and Man11, respectively, differed from each other by eight amino acid residues, and they were highly homologous to those of mannanases belonging to the glycosyl hydrolase family 26. The 26 amino acid stretch in the N-terminus of Man6 and Man11 was a predicted signal peptide. Both Man6 and Man11 were localized at the level of 94–95% in an intracellular fraction of recombinant E. coli cells. The enzymes hydrolyzed both locust bean gum and mannooligosaccharides, including mannotriose, mannotetraose, mannopentaose, and mannohexaose, forming mannobiose and mannotriose as predominant products. The optimal reaction conditions were 55°C and pH 6.0 for Man6, and 60°C and pH 5.5 for Man11. Man11 was more stable than Man6 at high temperatures.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.901-906
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• 1997

In order to reproduce and improve quality of traditional kochujang, various raw materials were added to prepare kochujang by replacing part of the glutinous rice. Chemical composition, microbial characteristics and enzyme activities were investigated during fermentation. Crude protein and salt contents of kochujang did not change significantly during fermentation, but moisture contents increased linearly. The pH and titratable acidity of kochujang changed little in garlic added group. The viable cell counts of aerobic bacteria and yeasts in the kochujang increased until 60 days of fermentation and then decreased slowly except for the garlic added group in which they increased during the last period of fermentation. Aerobic bacterial count did not show any remarkable differences among the samples and slowly decreased after 60 days of fermentation. The activities of liquefying and saccharifying amylases decreased until 45 days, but increased at 60th day. Acidic protease activities of each group were strong during the initial period, but neutral protease showed the highest activity from the 30 to 45 days of fermentation. Protease activities increased by addition of soy sauce, Chinese matrimony vine and purple sweet potato.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.258-266
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• 2014

Sweet potato soju (SPS), a form of traditional distilled alcoholic liquor in Korea, is manufactured by the distillation of fermented broth under normal pressure, thus providing it for a uniquely smooth taste infused with the flavor of sweet potato. After distillation, the lees of SPS is produced as by-product and discarded. In this study, the ethanol and hot water extracts of lees of SPS, and their subsequent organic solvent fractions using hexane, ethylacetate (EA), butanol, and water residue were prepared in an effort at the efficient re-use of the lees of SPS. The ethanol extraction yield was 1.36-fold higher than that of the hot water extraction, and the EA fraction revealed the highest total polyphenol content among the solvent fractions. The various extracts and solvent fractions did not demonstrate hemolytic activity at up to 0.5 mg/ml concentrations against human red blood cells. In the bioactivity assay, only the EA fraction displayed a broad spectrum of anti-microbial activity against different pathogenic and food spoilage bacteria, and demonstrated significant anti-coagulation activity by inhibitions of thrombin, prothrombin and blood coagulation factors. Furthermore, only the EA fraction from the hot water extract of the lees of SPS showed anti-platelet aggregation activity, which is comparable to aspirin (a commercially available drug). Our results suggest that the EA fraction of the hot water extract prepared from the lees of SPS has a high potential as a novel resource for anti-microbial and anti-thrombosis agents.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.2
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• pp.161-166
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• 2003

This study attempted to fortify Kimchi with water extracts of shells of shellfishes (corb shell, short neck clam, taste clam, ark shell, top shell, oyster) as natural resource of calcium. Kimchi added with the shell extracts in 5% were fermented at 1$0^{\circ}C$ with measurements in chemical, microbiological and sensory qualities. Calcium content of shellfish shells before water extraction was in the range of 25.57~38.78%. Kimchi added with the extracts showed higher pH, lower acidity, lower total aerobic bacterial count and higher lactic acid bacteria count compared to control Kimchi without any addition. After 7 day fermentation the Kimchi added with the extracts also showed higher ash and calcium contents compared to control products (3.3~5.0 vs. 2.8~3.0% and 300~376 vs. 70~95 mg%). Kimchi with oyster shell extract gave the most pronounced effect in ash and calcium contents. The addition of extract made Kimchi crisper and less sourer oganoleptically. In the overall acceptability, the Kimchi fortified with the shell extracts were better than control after 14 day fermentation.