• Food Science and Biotechnology
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• v.18 no.3
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• pp.700-705
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• 2009

In this study, the volatile compounds in 9 commercial fermented soybean pastes were extracted and analyzed by headspace-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS), respectively. A total of 63 volatile components, including 21 esters, 7 alcohols, 7 acids, 8 pyrazines, 5 volatile phenols, 3 ketones, 6 aldehydes, and 6 miscellaneous compounds, were identified. Esters, acids, and pyrazines were the largest groups among the quantified volatiles. About 50% of the total quantified volatile material was contributed by 5 compounds in 9 soybean paste samples; ethyl hexadecanoate, acetic acid, butanoic acid, 2/3-methyl butanoic acid, and tetramethyl-pyrazine. Three samples (CJW, SIN, and HAE) made by Aspergillus oryzae inoculation showed similar volatile patterns as shown in principal component analyses to GC-MS data sets, which showed higher levels in ethyl esters and 2-methoxy-4-vinylphenol. Traditional fermented soybean pastes showed overall higher levels in pyrazines and acids contents.

• Journal of Microbiology and Biotechnology
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• v.25 no.9
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• pp.1519-1527
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• 2015

Biogenic amines in some food products present considerable toxicological risks as potential human carcinogens when consumed in excess concentrations. In this study, we investigated the degradation of the biogenic amines histamine and tyramine and the presence of genes encoding histidine and tyrosine decarboxylases and amine oxidase in Bacillus species isolated from fermented soybean food. No expression of histidine and tyrosine decarboxylase genes (hdc and tydc) were detected in the Bacillus species isolated (B. subtilis HJ0-6, B. subtilis D'J53-4, and B. idriensis RD13-10), although substantial levels of amine oxidase gene (yobN) expression were observed. We also found that the three selected strains, as non-biogenic amineproducing bacteria, were significantly able to degrade the biogenic amines histamine and tyramine. These results indicated that the selected Bacillus species could be used as a starter culture for the control of biogenic amine accumulation and degradation in food. Our study findings also provided the basis for the development of potential biological control agents against these biogenic amines for use in the food preservation and food safety sectors.

• Journal of Microbiology and Biotechnology
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• v.25 no.4
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• pp.479-491
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• 2015

Lactobacillus species have been shown to enhance intestinal epithelial barrier function, modulate host immune responses, and suppress the growth of pathogenic bacteria, yeasts, molds, and viruses. Thus, lactobacilli have been used as probiotics for treating various diseases, including intestinal disorders, and as biological preservatives in the food and agricultural industries. However, the molecular mechanisms used by lactobacilli to suppress pathogenic bacterial infections have been poorly characterized. We previously isolated Lactobacillus plantarum JSA22 from buckwheat sokseongjang, a traditional Korean fermented soybean food, which possessed high enzymatic, fibrinolytic, and broad-spectrum antimicrobial activity against foodborne pathogens. In this study, we investigated the effects of L. plantarum JSA22 on the growth of S. Typhimurium and S. Typhimurium-induced cytotoxicity by stimulating the host immune response in intestinal epithelial cells. The results showed that coincubation of S. Typhimurium and L. plantarum JSA22 with intestinal epithelial cells suppressed S. Typhimurium infection, S. Typhimurium-induced NF-κB activation, and IL-8 production, and lowered the phosphorylation of both Akt and p38. These data indicated that L. plantarum JSA22 has probiotic properties, and can inhibit S. Typhimurium infection of intestinal epithelial cells. Our findings can be used to develop therapeutic and prophylactic agents against pathogenic bacteria.

• The Korean Journal of Mycology
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• v.52 no.1
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• pp.35-54
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• 2024

With a history spanning 9,000 years, yeast has played a central role in the traditional production of fermented foods, particularly alcohol and bakery. Recent research has highlighted the versatility of yeast in various industries, including the production of bioactive compounds, bioethanol, pigments, and enzymes, and as a host for molecular biology studies. In Korea, yeast isolation has traditionally focused on traditional fermented foods such as soybean paste. However, there is a growing trend in the isolation and characterization of yeasts from natural environments such as flowers and fruits for industrial applications. In this study, we isolated and identified 12 yeasts from various natural environments in Korea, including botanical gardens and parks that are not listed on the National Species List of Korea (NSLK). These newly discovered species included Sakaguchia oryzae, Cystobasidium raffinophilum, Meira argovae, Kazachstania humilis, Meyerozyma smithsonii, Anthracocystis trispicatae, Naganishia brisbanensis, Tremella yokohamensis, Kwoniella shandongensis, Kwoniella newhampshirensis, Aureobasidium proteae, and Rhodotorula dairenensis.

• Journal of the Korean Society of Food Culture
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• v.16 no.3
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• pp.260-267
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• 2001

This study was conducted to investigate the physicochemical characteristics of Sunchang traditional kochujang(fermented hot pepper-soy bean paste) for quality standardization. The kochujang samples, which have been fermented for 8 months in 1999, were collected from 20 firms at folk village in Sunchang area and analyzed their chemical compositions and color reference. The mean value of moisture, amino-type nitrogen, pH, acidity and salt content of the samples collected were $44.62{\pm}1.79%$, $132.66{\pm}21.67\;mg%$, $4.52{\pm}0.08$, $15.77{\pm}1.62$ and $8.76{\pm}1.55%$, respectively. The moisture, pH, acidity and salt content of each sample did not show much differences among samples. The Hunter values(L, a and b) of Sunchang traditional kochujang were $25.72{\pm}1.58$, $23.26{\pm}1.71$ and $9.86{\pm}0.94$, respectively. The mean content of amino-type nitrogen of Sunchang traditional kochujang was $132.66{\pm}21.67\;mg%$, and there were a little difference between the minimum(100.33 mg%) and the maximum(164.56 mg%). The main free sugars of Sunchang traditional kochujang were fructose($1.86{\pm}1.01%$), dextrose($4.29{\pm}2.06%$), sucrose($0.54{\pm}1.21%$), and maltose($1.48{\pm}0.77%$). The contents of fructose, dextrose, and maltose had little difference among samples. The fatty acids in Sunchang traditional kochujang were composed of palmitic, stearic, oleic, linoleic, linolenic, octadecatetraenoic, arachidonic and behenic acid. The linoleic acid(18:2) showed the highest, occuping 59.37% of the total fatty acids.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.252-259
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• 2009

We previously isolated Bacillus strains with high fibrinolytic activities (FAs) from cheonggukjang prepared by traditional ways. To test their potential as starters for cheonggukjang, soybean was fermented for 72 hr at $37^{\circ}C$ with each isolate and a control lab strain: B. subtilis CH3-25 (BS3-25), B. amyloliquefaciens CH51 (BA51), B. amyloliquefaciens CH86-1 (BA86-1), and B. subtilis 168 (BS168, control, lab strain). Viable cell numbers of all cheonggukjang samples rapidly increased and reached about $10^9$ CFU/g after 6 hr. During 72 hr, the initial pH of 6.3 rapidly increased to 8.1$\sim$8.2 for cheonggukjang fermented with BS3-25 or BA86-1, and 7.3 for those with BA51 or BS168. FAs and protease activities (acid, neutral, and alkaline) rapidly increased in cheonggukjang fermented with BS3-25, BA51, or BA86-1 during the first 12 hr. On the other hand, those of cheonggukjang fermented with BS168 slightly increased during the first 36 hr. There were significant changes in acid and neutral protease activities in cheonggukjang fermented with BA51 or BA86-1 during the 24 hr. Rapid increases of $\beta$-glucosidase activity corresponded well with rapid increases of $\alpha$-amylase and $\alpha$-galactosidase activities in addition to increases in antioxidant activities and the TPCs (total phenolic contents). The highest increase in the TPCs was observed in cheonggukjang fermented with BA86-1 while the least was that fermented with BS168.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1759-1762
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• 2015

Tarak is a Korean traditional fermented milk product that is fermented by adding rice wine to milk. Tarak was produced with Lactobacillus paracasei ssp. paracasei M13-65-3 isolated from rice wine, and its effects on immune cell proliferation and melanin biosynthesis were investigated. Tarak extract significantly increased proliferation of T lymphocyte Jurkat clone E6-1 cells at concentrations from 10 to $100{\mu}g/mL$. Tarak inhibited activities of tyrosinase and ${\alpha}$-melanocyte-stimulating hormone-induced melanin biosynthesis in mouse skin B16-F10 cells at a concentration of $100{\mu}g/mL$. These results suggest that tarak might have functionalities for enhancing the immune system by increasing immune cell proliferation and regulating melanin biosynthesis.

• Nutrition Research and Practice
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• v.2 no.3
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• pp.165-170
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• 2008

Protein-energy malnutrition is regarded as one of the public health problems in developing countries as a result of poor feeding practices due to poverty. This study, therefore, aimed at evaluating nutritional quality of a potential weaning food formulated from locally available food materials. The cooking banana fruit(CB) and bambara groundnut seeds(BG) were purchased from local market in Akure, Ondo State, Nigeria. The CB and BG were processed into flours, mixed in ratios of 90:10, 80:20, 70:30 and 60:40 and subjected into proximate, sensory and biochemical analyses using standard procedures. Nutrend(a commercial formula) and ogi(corn gruel, a traditional weaning food) were used as control. The nutritient composition(g/100 g) of the food samples were ranged as follows: moisture 2.94-6.94, protein 7.02-16.0, ash 1.76-2.99, fat 0.76-8.45, fibre 1.52-3.75, carbohydrate 63.84-88.43 and energy 1569.8-1665.7 kcal. The biological value(BV), net protein retention(NPR), protein efficiency ratio(PER) and feed efficiency ratio(FER) of the experimental food samples were significantly(p<0.05) lower than nutrend, but higher than ogi. The haematological variables of rats fed with formulated food samples, commercial formula(nutrend) and traditional weaning food(ogi) were not significantly(p>0.05) influenced by the dietary treatment. However, the values obtained for red blood cell(RBC), white blood cell(WBC), pack cell volume(PCV) and erythrocyte sedimentation rate(ESR) were higher in the experimental food samples than the commercial food. The growth rate of animals fed with experimental food samples were lower than those fed with the nutrend, but higher than those fed with ogi. In conclusion, the nutritional quality of CB and fermented BG mix of 60:40 ratio was better than ogi; and comparable to the nutrend. This implies that it can be used to replace low quality traditional weaning food and the expensive commercial weaning formula.

• The Korean Journal of Mycology
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• v.43 no.3
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• pp.196-199
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• 2015

The occurrence and characterization of yeast isolated from Korean traditional nuruk were investigated. Sequences of the D1/D2 domain of the 26S rDNA were identical for a strain examined and had a similarity value of 100% compared to sequences of the type strain of Saccharomyces cerevisiae (NRRL Y-12632). The isolate able to assimilate with trehalose, raffinose, and methyl-glucoside assimilate was also capable of glucose, galactose, maltose, and sucrose fermentation. It did not proliferate at $40^{\circ}C$ or above, but was able to grow in concentration of 50% glucose and 10% NaCl. By combining nucleotide sequence, morphological observation, and physiological characteristics, the isolate was identified as S. cerevisiae.

• Journal of Biomedical and Translational Research
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• v.19 no.4
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• pp.103-109
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• 2018

Aspergillus luchuensis 34-1 was inoculated into wheat pellets with different conditions of raw materials to produce nuruk. The degree of substrate reactivity improvement of steam treated raw materials compared with that of non-heat treated was analyzed. The water content of the pellet was adjusted to 25% and 35%, and steam treatment for 10 minutes improved the substrate reactivity at 2.1-fold and 3.1-fold, and sterilization was also possible. The characteristics of improvement pellet nuruk were investigated according to the degree of crushing and water content of raw materials according to the temperatures and humidities ($23^{\circ}C$, $30^{\circ}C$ and RH 60%, RH 80%). The pH of the pellet nuruk was higher depending on the temperature, humidity and moisture content of the koji were lower, and the pH of the flour-pellet nuruk was lower than that of 2 mm milling wheat-pellet nuruk according to milling degree. It can be seen that the milling degree affects the growth of mold. The acidity and amino acid were generally higher as fermentation time increased. Also, the higher the incubation temperature, humidity and moisture content, the higher the value. Glucoamylase activity was significantly the highest in moisture content 35% D2b nuruk, cultured at $30^{\circ}C$ and 80% RH for 38 hours. This is higher than the previous reports on glucoamylase of rice-koji or commercial nuruk using fungi isolated from traditional nuruk. From these study, it is expected that making of improvement pellet nuruk would save the fermentation time considerably compared with traditional nuruks.