• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.2
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• pp.255-260
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• 1996

증편반죽의 발효에 따른 해면상의 조직(망상구조)형성능의 mechanism을 조사하기 위하여 반죽의 구성성분의 경시적 물성 및 효소(diastase 및 protease) 활성의 변화, 구성 전분 분획의 glucose chain length 변화 및 1% SDS에 의해서 용출되는 단백질 분획의 변화에 대해서 검토하였다. 발효가 진행됨에 따라 증편반죽의 pH는 감소한 반면 점성 및 부피는 발효경과 10시간가지 증가하다가 그 이후로는 약간 감소하는 경향을 보였다. 발효의 진행과 더불어 diastase의 활성은 증가하였으며, 쌀전분 분획 중 amylose의 함량은 약간 감소하였다. 그리고 전분분자의 $\alpha-1,6-glucoside$ 결합을 isoamylase(debranching enzyme)로 가수분해시킨 후 Sephadex G-75를 이용한 chromatogram 분석에 의하면 쌀가루 전분 분획과 증편반죽 전분 분획의 glucose chain length 분포는 거의 유사하지만 발효가 진행됨에 따라 중합도가 낮은 부분이 우선적으로 diastase의 작용을 받은 것이라고 생각되어진다. 한편, 발효가 진행된에 따라 protease의 활성은 증가하고 있었음에도 불구하고 증편반죽의 당에 의한 단백질 분획의 고분자화가 Suprose CL-12 column chromatogram 상에서 관찰되었는데, 이것은 아마도 발효과정 중 증편반죽에 공존하는 미생물들의 발효산물인 당질(gum질)을 매개로 한 단백질 분자의 회합에 의한 결과라고 생각되어진다. 따라서 이러한 결과를 미루어 볼 때 증편반죽의 망상구조 형성능은 발효과정 중 일어나는 당과 단백질간의 상호작용에 의한 결과라 생각되어진다.

• Applied Biological Chemistry
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• v.49 no.4
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• pp.276-280
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• 2006

Traditionally fermented Cheonggukjangs were collected from Gyeonggi and Gangwon provinces and 22 strains were isolated and identified by using 165 rDNA sequences. Most of the identified strains were Bacillus subtilis and B. licheniformis, B. subtilis and B. licheniformis are dominant in the Gyeonggi area and B. licheniformis in the Gangwon area. In the growth pattern of the isolated strains, the duration of lag phase was generally 5 to 7 hours and stationary phase was reached after 23 to 40 hours of incubation. Total cell populations at the stationary phase were between $1{\times}10^6\;CFU/ml$ and $5{\times}10^7\;CFU/ml$. The fermenting ability of carbohydrates of isolates showed some differences among the regions. The isolated strains from Yong-In, Gyeonggi showed higher fermenting abilities with D-xylose, xylitol, D-tagatose and Methyl-$\alpha$-D-mannopyranoside. D-lactose, D-tagatose, D-xylose, Methyl-$\alpha$-D-mannopyranoside, amygdalin, arbutin, esculin and 2-keto-gluconate were well fermented with the An-Seong's strains; L-rhamnose, inositol, D-mannitol, D-sorbitol, celibiose and gluconate with the Kawang-Ju's stains; and D-lactose with the Odaesan's strains.

• Microbiology and Biotechnology Letters
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• v.3 no.3
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• pp.123-134
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• 1975

Out of 96 yeast strains isolated from various natural habitats, five strains were screened based on their ability to ferment agricultural biproducts such as rice-, barley-and wheat-bran, and sawdust. These were identified as Hansenula anomala var anomala, Candide utilis, C. pelliculosa, Debaryomyces hansenii, and Irpex lacteus. Using these yeasts the above mentioned agricultural biproducts were fermented in various combinations. The fermented product was fed to 180 male Starcroses for eight weeks and obtained a body weight increase of 15.1g a day, while the unfermented control feed increased 10.5g a day.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.943-950
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• 2003

To identify the functional properties of Hongkuk ju and to improve its brewing process, Hongkuk ju was brewed using different hongkuks (Monascus red koji) made by Monascus purpureus, Monascus anka, Monascus aruneosus, and nuruk. Hongkuk using M. purpureus showed the highest enzyme activity. Hongkuk ju prepared with the M. purpureus hongkuk was fermented most efficiently, and showed the highest Hunter value. Hongkuk ju showed significant levels of phenolic compounds, electron donating ability, nitrate-scavenging activity, and ACE inhibition activity. In particular, Hongkuk ju made with M. purpureus showed the highest value among the wines of this study.

• Microbiology and Biotechnology Letters
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• v.16 no.6
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• pp.489-493
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• 1988

To obtain a new yeast strain that is able to efficiently produce ethanol from starch, the glucoamylase gene of Saccharomyces diastaticus was transformed into S. cerevisiae without a cloning vector. The competent cells of S. cerevisiae, induced by the treatment of Li$_2$SO$_4$, were transformed with the partial BamHI-digests of chromosomal DNA of S. diastaticus, and the transformants were selected by their abilities to utilize and ferment starch. The transformants, which appeared at a frequency of 8.5$\times$10$^{-7}$, were able to withstand up to 800 ppm of copper sulfate like the recipient and retained the phenotypic expression of the recipient with the exception of the acquisition of STA gene and MAL gene, as regards fermentation of carbohydrates. The enzymatic properties of glucoamylases produced by transformants were very similar to those produced by S. diastaticus as based on optimium pH and temperature.

• Journal of Applied Biological Chemistry
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• v.53 no.4
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• pp.212-218
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• 2010

This study was aimed to investigate the contents of chemical components and the biological activity of fermented Omija (Schizandra chinensis Baillon.) beverage (FOB), which have not been well known up to now. General compositions and the contents of mineral and vitamin of FOB were lower than Omija before fermentation (OBF). In addition, most sucrose was digested into glucose and fructose in FOB. This suggests that the beneficial contents may be made from general compositions by fermentation, though more evidences are needed. Antioxidant activity of FOB was measured by using 2,2-diphenyl-l-picryl-hydrazyl (DPPH) free radical scavenging activity and superoxide dismutase-like activity (SODA). DPPH radical scavenging activity and SODA were increased in a dose-dependent manner, and were about 79.7% and 60.8% at four times diluted FOB (25% of FOB), respectively. The FOB also showed strong antibacterial activity on Escherichia coli. Beauty effect of FOB was demonstrated by the analysis of tyrosinase and elastase inhibitory activities, and they were remarkably increased in a dose-dependent manner. Tyrosinase inhibitory activity was about 82% at two times diluted FOB (50% of FOB) and elastase inhibitory activity was 78.2% at five times diluted FOB (20% of FOB). These results suggest that FOB has a strong antioxidant activity, and tyrosinase and elastase inhibitory effects.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.445-454
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• 2022

This study aimed to improve the physiological activity of onion juice via lactic acid bacterial fermentation. Seven types of lactic acid bacteria were used for the fermentation of onion juice. The pH and sugar content of the onion juice decreased, while its titratable acidity increased after lactic acid bacteria fermentation, and the cell count of lactic acid bacteria was 7.31-10.40 log CFU/mL. The total free sugar content decreased, while the total organic acid content increased in the fermented onion juice. Quercetin content of the fermented juice was 0.13-0.53 mg/kg. The total polyphenol and flavonoid contents increased after fermentation. Additionally, the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical cation scavenging activities were increased by fermentation. Overall, lactic acid bacteria fermentation of onion juice enhanced its physiological activity. Based on these findings, Bifidobacterium breve KCTC 3441 was selected as the onion juice fermentation strain.

• Food Science and Preservation
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• v.17 no.4
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• pp.563-570
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• 2010

We sought to ferment wine from mulberry (Morus alba) juice. The soluble solid content was $9.5{\sim}14.5^{\circ}brix$ on day 6 of fermentation, and gradually fell later; sugar was not further consumed when $3^{\circ}brix$ was attained. Alcohol content rose dramatically on day 6 of fermentation, being 4.5% (v/v) at fermentation temperatures of 16C and 18C, 6.5% (v/v) at 20C, and 8.0% (v/v) at 25C, rising further to 10.5~11.5% (v/v) on day 48, at higher culture temperatures. Citric acid, malic acid, and oxalic acid were present in mulberries. The levels of both citric and oxalic acid fell after fermentation, whereas malic acid concentration increased. All of fructose, glucose, maltose, and sucrose were fermented. Electron-donating ability (EDA) was elevated to over 90% of the control value in mulberry juice diluted to 40% (v/v). SOD-like activities in juice and wine were 80.1% and 72.1% of the control value. Nitrite-scavenging abilities (NSAs) were 86.2% and 85.2% of control in undiluted juice and wine, respectively. Mulberry juice had an activation level higher than that of mulberry wine, but functionality neither rose nor fell after fermentation. Insensory evaluation, the overall wine score was better than average, at 5.00, demonstrating the commercial potential of mulberry wine.

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.129-133
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• 1990

The strain of Nuruk yeat No. 15 (NY-15) which ferments lactose in milk was Isolated from Nuruk and identified as Saccharomyces marxianus according to the API 20C profile index. The lactose hydrolysing ability of NY-15 was similar to that Saccharomyces fragilis ATCC 8583 which has ${\beta}-galactosidase$ activity. Its optimum growth temperature, pH and time for the production of maximum enzyme activity showed $28^{\circ}C$, 4.5 and 28hr, respectively. Galactose as well as sucrose as carbon sources, and urea as nitrogen source Increased the production of enzyme. In order to test the production of alcohol, NY-15 was inoculated in whey medium and whey medium added with sugar. In the former, NY-15 produced 2% alcohol and in the latter, it showed 12% alcohol production. The optimal medium pH for lactose hydrolysis of NY-15 is 4.5, whereas that of Saccharomyces fragilis ATCC 8583 is 3.5

• Food Science and Preservation
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• v.30 no.2
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• pp.321-333
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• 2023

The study investigated the pH, acidity, soluble solids, total sugar, polyphenol, flavonoid, anthocyanin content, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, and color of kombucha with a variety of added fruit peels during the fermentation process. Pear, grape, plum, orange, apple, and golden kiwi peels were added during fermentation. The pH showed a decrease, while an increase in acidity was observed. An increase in soluble solids, which was higher in most experimental groups than the control group, was also observed. A decrease in total sugar was observed over time. However, an increase was observed in reducing sugar. On Day 0, higher total sugar and reducing sugar were detected in the peel addition group compared with the control group. The antioxidant capacity of polyphenol, flavonoid, anthocyanins, and DPPH radicals scavenging increased with fermentation and was higher in all addition groups, except for pear, compared with the control group. Except for grapes and plums containing high levels of anthocyanins, an increase in the L-value was observed over time, and an increase in the a-value of grapes and plums was also observed (p<0.05). The possible utilization of inedible fruit peel in kombucha was shown. Applying inedible fruit peels to kombucha is proposed to increase antioxidant content and modulate color and pH.