• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.47-53
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• 2010

Bacteria strains with high activities of extracellular enzymes (protease, fibrinolytic enzyme, amylase, cellulase, and lipase) were isolated from Jeju traditional fermented soybean paste (Doenjang), and characterized by 16S rRNA gene sequence analysis and physiological properties. Protease activities were higher in JR14, JR19, JR25, JR32, JR38, JR47, and JR64 than Bacillus subtilis KCCM 12027 (standard strain). Amylase activities were shown in JR6, JR25, JR38, JR56 and JR81, while not in KCCM12027. Cellulase activities were higher in JR6, JR14, JR48, and JR65 than those of other isolated strains and KCCM 12027 whereas lipase activities were the higher in JR-14 and JR-48. Thrombolytic activity in JR19 with high hemolysis activity were 192% compared with that of plasmin as a positive control. Zymogram analysis indicated that the thrombolytic active strains had 4~5 bands in the molecular weight range of 25~75 kDa. Gene sequence analysis of rRNA revealed that the isolated stains had 99% homology with Bacillus species, and the thrombolytic active stain JR19 was B. stratosphericus $41KF2a^T$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.3
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• pp.378-383
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• 2002

The aim of the study was to analyze N-nitrosamine (NA) and its precursors in serveral fermented foods which were treated with nitrite, thiocyanate and ascorbic acid under simulated gastric digestion. Every analyzed sample contained nitrate, with levels ranging from 0.3 to 1.3 mg/kg, but nitrite was present at very low levels of less than 0.3 mg/kg. And other precursors of amines such as dimethylamine and trimethylamine were detected less than 0.5 mg/kg in every samples. N-nitrosodimethylamine (NDMA) was detected in the levels of <0.5 ∼ 2.7 ug/kg in soy sauce,1.5∼3.1 ug/kg in soybean paste and <0.5∼1.8 ug/kg in beer, while NDMA levels increased by 1.1∼4.5 times in the fermented foods which were digested under simulated gastric conditions.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.157-161
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• 1996

Physicochemical and microbial characteristics of traditional kochujang (fermented hot pepper-soybean paste) collected from 55 households at different regions were investigated. The traditional kochujang contained $46.71{\pm}5.98%$ moisture, $46.87{\pm}8.83%$ total sugar, $11.77{\pm}3.90%$ crude protein, $15.01{\pm}6.48%$ salt, $27.52{\pm}7.32%$ reducing sugar, $0.26{\pm}0.15%$ amino nitrogen and $2.69{\pm}2.35%$ ethanol. The pH and titrable acidity were $4.60{\pm}0.23$ and $27.26{\pm}10.98\;ml/10\;g$, respectively. The average water activity of traditional kochujang were $0.79{\pm}0.04$. The Hunter L, a, and b values of kochujang were $16.03{\pm}2.89$, $20.42{\pm}4.37$, and $9.71{\pm}1.92$, respectively. The viable cell counts of aerobic, anaerobic bacteria and yeasts in the traditional kochujang were $1.02{\times}10^8{\pm}1.29{\times}10^8\;CFU/g$, $2.24{\times}10^7{\pm}3.90{\times}10^7\;CFU/g$ and $5.90{\times}10^5{\pm}2.25{\times}10^6\;CFU/g$, respectively. The kochujang collected from various regions showed quite strong liquefying and saccharogenic amylase and protease at different level by samples.

• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.152-156
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• 1996

Taste components of traditional kochujang from 55 households were investigated. The major free sugars in traditional kochujang (fermented hot pepper-soybean paste) were glucose $(8.21{\pm}5.62%)$ and maltose $(6.95{\pm}7.27%)$ and the minors were fructose $(1.88{\pm}1.27%)$ and sucrose $(1.05{\pm}1.21%)$. Succinic $(901.83{\pm}826.23\;mg%)$, citric $(484.16{\pm}242.89\;mg%)$ and lactic $(381.63{\pm}367.88\;mg%)$ acids in traditional kochujang were found in large amounts and acetic, oxalic, and formic acids in smaller amounts. The traditional kochujang contained large amounts of proline $(10.66{\pm}6.27\;mg%)$, glutamic acid $(9.27{\pm}10.97\;mg%)$, aspartic acid $(9.14{\pm}5.84\;mg%)$, lysine $(6.19{\pm}6.66\;mg%)$, and serine $(5.72{\pm}3.79\;mg%)$, and the total free amino acid content was 64.35mg%. Among the nucleotides and their related compounds in traditional kochujang, CMP $(42.90{\pm}28.16\;mg%)$ were the most abundant major compounds and hypoxanthine $(6.86{\pm}3.45\;mg%)$, IMP $(5.59{\pm}5.84\;mg%)$, inosine $(4.58{\pm}6.91\;mg%)$ and GMP$(3.36{\pm}3.93\;mg%)$ were found in smaller amounts, and AMP and UMP were also found in minor.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.82-89
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• 1997

Monascus anka produces biologically active materials, and liquid M. anka koji was employed for preparing fermented hot pepper soybean paste (kochujang). Three kinds of koji (M. anka, Aspergillus oryzae and mixed koji) were used to prepare kochujang, and changes of physicochemical characteristics were examined during fermentation. A. oryzae koji showed the highest ${\alpha}-amylase$ and protease activities; whereas, M. anka koji showed the highest ${\beta}-amylase$ activity in liquid koji. Water content of kochujang continuously decreased, whereas viscosity increased during fermentation. The water content and viscosity was 46% and $1.4{\times}10^5\;cP$, respectively after 40 days of fermentation. The pH of kochujang with M. anka and/or A. oryzae koji was $4.63{\sim}4.65$ in the beginning and was between 4.53 and 4.67 after 40 days of fermentation. L-, a- and b-values decreased rapidly during fermentation until 20 days of fermentation. After 40 days, L- and b-values of kochujang prepared with M. anka koji showed lower values than A. oryzae, and a-value showed higher values as the amount of M. anka koji increased. Ammoniacle nitrogen content continuously increased during fermentation. Amino nitrogen content was the highest, 241.2 ㎎%, and ammoniacle nitrogen was the lowest, 97.2 ㎎%, in kochujang prepared with A. oryzae. However, amino and ammoniacle nitrogen content showed no difference between M. anka and A. oryzae koji kochujang. Kochujang prepared with M. anka koji showed a potential that kochujang can be manufactured lower level of red pepper than previously used.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.152-164
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• 2018

Fermented seasoning pastes were prepared by Aspergillus oryzae and Bacillus subtilis using three edible insects, Tenebrio molitor larvae (TMP), Gryllus bimaculatus (GBP), and Bombyx mori pupa (SPP), with soybean (SBP) as a negative control. Volatile compounds were extracted by the headspace solid-phase microextraction (HS-SPME) method and confirmed by gas chromatograph-mass spectrometry (GC-MS). In total, 121 volatiles from four samples were identified and sub-grouped as 11 esters, 18 alcohols, 23 aldehydes, 5 acids, 10 pyrazines, 2 pyridines, 7 aromatic hydrocarbons, 10 ketones, 19 alkanes, 9 amides, 4 furans and 3 miscellaneous. TMP, GBP, SPP and SBP had 48, 54, 36, and 55 volatile compounds, respectively. Overall, 2,6-dimethylpyrazine and trimethylpyrazine were found by a high proportion in all samples. Tetramethylpyrazine, a main flavor of doenjang, a Korean fermented seasoning soybean paste, was identified as one of the major compounds in TMP, SPP, and SBP. SBP had benzaldehyde, hexanal, n-pentanal, and aldehydes and SPP with pyrazines.

• Nutrition Research and Practice
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• v.16 no.4
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• pp.435-449
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• 2022

BACKGROUND/OBJECTIVES: Cheonggukjang is a traditional fermented soybean paste with significant health-promoting effects. On the other hand, there have been insufficient studies on the safety and efficacy of Cheonggukjang, which is produced using traditional methods containing toxins and biogenic amines (BAs). This study compared the laxative effect of Cheonggukjang, containing high or low levels of toxins and BAs (HTBC or LTBC) in a loperamide (Lop)-induced constipation mouse model. MATERIALS/METHODS: To induce constipation, Lop (5 mg/kg) was administered orally to ICR mice twice a day for 4 days, and the dose was increased to 8 mg/kg after a 3-day rest period. Cheonggukjang (500 mg/kg, HTBC, or LTBC respectively) was administered for four weeks before the Lop treatment. RESULTS: The number of stools, fecal weight, water contents, gastrointestinal transit, and histological alterations were recovered significantly in the HTBC or LTBC groups. HTBC and LTBC administration did not induce significant changes in body weight, dietary intake, and behavior. The opioid-receptor downstream signaling pathway in colon tissues was also evaluated. The c-Kit, stem cell kinase, and mitogen-activated protein kinases subfamilies, including extracellular signal-regulated kinase 1/2, c-Jun N-terminal kinases, and p38, were all downregulated in the HTBC or LTBC-administered mice colon compared to the Lop group. CONCLUSION: These results show that Cheonggukjang, containing high levels of toxins and BAs, have a similar laxative effect in a mouse model of Lop-induced constipation.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.190-197
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• 2013

Three slime-forming lactic acid bacteria were isolated from traditional Korean fermented soy sauce and soybean paste and shown to produce exopolysaccharides (EPS) in sucrose media. By isolating the strains, examining their morphological characteristics and determining their 16S rDNA sequences, N58-5 and K6-7 were identified as Leuconostoc mesenteroides and N45- 10 as Leuconostoc citreum. The acid and bile tolerances of these three strains were investigated. Amongst the three lactic acid bacteria, Leuc. citreum N45-10 exhibited the highest viability ($10^5-10^6$ CFU/ml) in 0.05 M sodium phosphate buffer (pH 0.3) for 2 h, in artificial gastric juice for 2 h and in 0.3%, 0.5% oxgall for 24h. Leuc. mesenteroides K6-7, N58-5 and Leuc. citreum N45- 10 were grown in sucrose liquid medium and 8.16 g/L, 3.65 g/L, 16.17 g/L of EPS was collected, respectively. The hydrolyzed EPS was analyzed by HPLC in order to determine the sugar composition of EPS. Leuc. mesenteroides K6-7 and N58-5 showed two peaks indicating glucose and fructose, thus they were determined to be hetero-type polysaccharides. Leuc. citreum N45-10 showed only the glucose polymer, indicating it to be a homo-type polysaccharide. In addition, all three lactic acid bacterial hemolysis did not demonstrate a clear zone in blood agar in the area surrounding a lactic acid bacteria colony.

• Food Science of Animal Resources
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• v.24 no.2
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• pp.103-107
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• 2004

This study was carried out to investigate the growth of pathogenic germ in fermented pork with Korean traditional seasonings. The samples, outside muscle of pork ham were cut by the shape of cube (7${\times}$12${\times}$2cm) and seasoned with five Korean traditional seasonings such as garlic paste (Tl), pickled Kimchi (T2), pickled Kimchi juice (T3), soybean paste (T4), red pepper paste (T5). The rate of meat to seasonings was same. The seasoned samples were fermented at -1${\pm}$1$^{\circ}C$ for 28 days. Microbial pathogens such as Escherichia coli O157, Listeria monocytogenes, Salmonella enteritidis were not detected in all paste and samples. When 1.5${\times}$l0$^3$ CFU/$\textrm{cm}^2$ of Escherichia coli O157 was inoculated, the numbers were slightly increased to 10$^3$-10$^4$ CFU/$\textrm{cm}^2$ at 3 days and gradually decreased to the level of inoculation at 18 days in all samples. In the inoculation with Listeria monocytogenes (8${\times}$l0$^4$ CFU/$\textrm{cm}^2$), the numbers were below 10$^3$ CFU/$\textrm{cm}^2$ during 28 days in T3 and T4, while they were increased to 10$\^$6/ CFU/$\textrm{cm}^2$ in Tl and T2 at 3 and 13 days respectively, and decreased to 10$^4$ CFU/$\textrm{cm}^2$. In the inoculation with Salmonella enteritidis (3${\times}$l0$^4$ CFU/$\textrm{cm}^2$), the numbers increased to 10$\^$5/ CFU/$\textrm{cm}^2$ at 18 days, but they were rapidly decreased to the level of initial inoculation at 23 days.

• Food Science and Preservation
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• v.22 no.4
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• pp.545-552
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• 2015

This study investigated the quality characteristics of popped rice Doenjang prepared with different Bacillus strains (Bacillus subtilis KACC 15935, and Bacillus subtilis HJ18-9). The changes in the enzyme activity (protease, cellulase, and ${\alpha}$-amylase), amino-type nitrogen and ammonia-type nitrogen contents, and the reducing sugar were investigated during the fermentation period. Enzymes such as protease, cellulase, and a-amylase plays an important role in the changes in composition of nutrients, and in flavor and taste of popped rice Doenjang. Protease activities of the popped rice deonjang fermented with different Bacillus strains (control, B. subtilis KACC 15935, and B. subtilis HJ18-9) was in the range of 171.77-185.97 unit/g at the beginning of fermentation, and there were no significant differences among the samples. On the other hand, the protease activity in popped rice Doenjang fermented with B. subtilis HJ18-9 increased significantly up to $248.77{\pm}4.53unit/g$ at the end of fermentation (p<0.05). Cellulase activity and a-amylase activity of popped rice Doenjang in HJ18-9 was higher than these of other samples. After 56 days of fermentation, amino-type nitrogen in popped rice deonjang fermented with control, B. subtilis KACC 15935, and B. subtilis HJ18-9 increased significantly up to $174.99{\pm}3.70$, $166.59{\pm}1.40$, $225.39{\pm}3.70mg%$, respectively (p<0.05). These results suggested that B. subtilis HJ18-9 was a suitable starter for the preparation of soybean paste.