• The Microorganisms and Industry
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• v.17 no.2
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• pp.18-21
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• 1991

생물은 자기 복제를 통한 생장이나 생명유지를 위해 에너지를 필요로 한다. 화학영양생물은 화학에너지를 발효 혹은 호흡을 통해 생물학적 에너지로 전환시키며, 광영양생물은 광합성 작용을 통해 광에너지를 이용한다. 발효, 호흡, 광합성은 모두 산화-환원 반응을 통해 이루어진다. 생물의 모든 에너지 전환반응은 산화-환원 반응, 즉 전자의 흐름으로 이루어지며 생명현상이 에너지를 필요로 하기 때문에 생명현상은 전자의 흐름으로 이루어진다고 할 수 있다. 모든 생물이 에너지 전환 반응에 산화-환원 반응을 이용한다는 말은 생물이 많은 종류의 산화-환원 효소를 보유하고 있다는 뜻이며, 실제 많은 종류의 산화-환원 효소가 발견되고 연구되었다.

• Korean Journal of Microbiology
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• v.48 no.3
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• pp.216-219
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• 2012

Chungkookjang, fermented soybean, is high in microorganism, enzymes, daidzein, and peptides. Using yellow, black, Seoritae, small-black soybeans and Bacillus licheniformis B1, each Chungkookjang (YC, BC, SC, SBC) was prepared, and their fermentation patterns were compared. Changes of pH and browning material formation were taken as an indicative of fermentation. YC had a high pH increase at an early stage of fermentation, and a low change at a late stage. BC, SC, and SBC showed different patterns with a low pH increase at an early stage and a high pH increase at a late stage. Formation rate of browning material was fastest in YC and slow in the rest of BC, SC, and SMC. SC showed the highest value of browning material formation 1 d after fermentation. Anthocyanin in black soybeans seems to suppress the growth of bacteria at an early stage of fermentation. When anti-inflammatory daidzein contents were analyzed by HPLC, BC, SC, SBC showed higher values than YC. It was demonstrated that black soybeans can be fermented with B. licheniformis B1.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1158-1165
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• 1997

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang during aging, which was prepared with a meju fermented for various periods of time. The number of bacteria was highest in all samples after 30 days of fermentation at $20^{\circ}C$, while that of mold in kochujang prepared with a 40-day- or 60-day-fermented meju was highest at 15th day of aging when yeast appeared. The activities of carbohydrases and proteases were highest in kochujang prepared with a 40-day-fermented meju followed by a 60-day-fermented meju. These results suggest that kochujang prepared with a meju aged for 40 days had the highest quality in terms of physicochemical, microbiological and enzyme activities of kochujang during fermentation.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.384-397
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• 2018

The aim of this study is to screen the strains of Bacillus spp. possessing safety, probiotic activity, and so on, which can be utilized as probiotic resource for using the feed and supplement food of companion animal. About 300 isolates were isolated from traditional Korean sauces, four isolates that did not have or produce the six kinds of B. cereus type vomiting and diarrhea toxin genes, ${\beta}$-hemolytic, and three kinds of carcinogenic enzymes were selected. Antibiotic gene retention, cell surface hydrophobicity, antibiotic sensitivity, and glucose utilization were analyzed for four isolates, and finally SRCM 100731 was selected. SRCM 100731 was named as Bacillus amyloliquefaciens SRCM 100731 16S rRNA sequencing analysis, and carried out optimization of cell growth for industrial applications such as pet food and feed. The effects of 14 different components on cell growth were investigated and three significant positive factors, molasses, sodium chloride, and potassium chloride were selected as the main factors based on a Plackett-Burman design. In order to find out optimal concentration on each constituent, we carried out central composite design. The predicted optimized concentrations were 7% molasses, 1.1% sodium chloride, 0.5% potassium chloride. Finally, an overall about 7-fold increase in dry cell weight yield ($12.6625{\pm}0.0658g/L$) was achieved using the optimized medium compared with the non-optimized medium ($1.8273{\pm}0.0214g/L$). This research is expected to be highly utilized in the growing pet industry by establishing optimal cultivation conditions for industrial application as well as screening Bacillus amyloliquefaciens SRCM 100731 as probiotic resource for companion animal.

• Korean Journal of Microbiology
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• v.35 no.4
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• pp.296-301
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• 1999

A Bacillus strain from Korean soil was isolated and identified to be Bacillus licheniformis B1 through various biochemical tests, VITEK, and MIDI system analysis. The strain produced extracellular amylase and protease. Whether or not the strain can perform Chungkookjang fermentation with autoclaved soybean and Kanjang fermentation was determined in this study. In Chungkookjang fermentation, browining materials of strong anti-oxidant increased 8-fold, and 2-fold in Kanjang, compared with initiation material for fermentation. Maximal protease activity in Chungkookjang was observed one day after inoculation. Protease activities in Kanjang decreased to the half, and then maintained constant values during fermentation, probably due to the inhibitory effect of salt on protease activities. High molecular mass of nucleic acids was identified in Chungkookjang and Kanjang. Since the nucleic acids were not observed in autoclaved soybean, they seem to be originated from B. licheniformis B1. This study demonstrated successive fermentation of Chungkookjang and Kanjang by B. licheniformis B1 isolated from nature, and suggested possible development of food rich in browing and nucleic acids.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.529-534
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• 2016

Bioethanol was produced using the separate hydrolysis and fermentation (SHF) method with macroalgal polysaccharides from the seaweed, Undaria pinnatifida as biomass. This study focused on the pretreatment, enzymatic saccharification, and fermentation of yeasts in co-culture. Ethanol fermentation with 14.5% (w/v) seaweed hydrolysate was performed using the yeasts, Saccharomyces cerevisiae KCTC 1126 alone, Pichia angophorae KCTC 17574 alone, and their co-cultures with the yeasts either adapted to mannitol or not. Among the combinations, the co-culture of non-adapted S. cerevisiae and P. angophorae adapted to mannitol showed high bioethanol production of 12.2 g/l and an ethanol yield ($Y_{EtOH}$) of 0.41. Co-culture in the SSF process was employed in this study, to increase the ethanol yields of 35.2% and reduction of 33.3% in fermentation time. These results provide suitable information on ethanol fermentation with marine seaweeds for bioenergy production.

• Microbiology and Biotechnology Letters
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• v.9 no.4
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• pp.219-223
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• 1981

Experiments on methane gas digestion were conducted to prevent livestock pollution and develop substitute energy. When about 30(w/w)% of sludge was added to cow feces, pig feces, and poultry feces and digested at 37$^{\circ}C$ for 20 days, methane gas produced per Kg of organic matter for cow feces, pig feces, poultry feces was 131, 248 and 235 l, respectively. pH decreased slightly at first but increased gradually afterwards during digestion period. When 20, 30, and 40(w/w)% of sludge were added to the mixture of cow feces (300g) and water (200g), the volumes of gas produced were 6.1, 14.5 and 13.4 l, respectively. Volume of methane gas produced from the mixture of cow feces and saw dust was much more than that from the mixture of cow feces and rice polishings. The contents of N, K, P for digestion residues were sufficient to be utilized as a fertilizer. When methane gas digestion was carried out with cow feces in a submersible pump digester the volume of methane gas produced per Kg of organic matter was 188 l. The price of total methane gas produced at this digestion was similar to that of the electric power consumed.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.65-65
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• 2018

복분자(Rubus coreanus Miquel)는 anthocyanin, phenolic acid, tannin, flavonoid, stilbenoid와 같은 생리활성물질이 풍부하게 존재하는 것으로 보고되었으며 항염증, 항암활성, 항산화효과 등 다양한 생리활성에 대한 효능이 있어 건강식품으로써 애용되고 있을 뿐만 아니라 약용성 건강보조식품 등으로 각광받고 있다. 생물전환(Bioconversion)은 미생물 또는 효소의 생물학적 촉매 기반 천연소재의 생리활성 물질기능성, 생체이용률, 안전성을 증대시키기 위한 방안으로 많은 연구가 진행되고 있으며 아울러 식품, 의약품, 화장품 등 다양한 분야에서 활성화 되고 있다. 본 연구는 불가사리 발효액으로부터 유산균을 분리하였으며, 유전학적 특성을 확인하기 위하여 16S rDNA 염기서열을 분석하였다. 전북 고창에서 수확된 복분자를 분말상태로 유산균과 발효공정을 수행하였으며, 복분자의 최적 추출조건 선정과 발효공정 전 후의 활성을 관찰하였다. 발효공정 후 추출물의 기능성 평가를 진행하기 위하여 DPPH radical scavenging activity, total polyphenol 함량을 확인하여 항산화 효능 및 유효성분 함량을 평가하였다. 또한 대식세포인 Raw 264.7을 사용하여 MTT assay, Nitric oxide (NO) 생성 억제 효능을 확인하여 세포독성 및 항염증 활성을 평가하였다. 실험결과, 발효기간이 다른 불가사리 비료발효액으로부터 16 종의 다양한 균주를 확보하였으며, 생물전환 공정에 유용 균주를 선정하기 위하여 복분자 분말의 발효공정을 실시한 결과 3 종의 유산균 처리군에서 무처리군 대비 DPPH radical 소거능 및 polyphenol 함량이 증가됨을 확인하였다. 그 중 가장 우수한 활성을 나타내는 균주를 16S rDNA 염기서열 분석한 결과 Lactobacillus coryniformis A6-4로 확인되었으며, 발효공정 후 항산화 활성은 무처리군 대비 약 115%, polyphenol의 함량은 무처리군 대비 약 121%로 증가됨을 확인되었다. 또한 발효공정 후 독성활성이 감소되는 경향을 확인되었으며, 항염증 활성이 유의적으로 증가됨을 확인하였다.

• Korean Journal of Microbiology
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• v.40 no.1
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• pp.49-53
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• 2004

Barley, wormwood, sea tangle, and soybean were fermented by Bacillus licheniformis B 1 to make Chungkookjang with better flavor and aroma. Maximal protease activity in mixed grains was observed one day after inoculation. pH increased to 8.4 two days after inoculation. Browning material derived from interaction between sugar and amino acids increased 20-fold. Thus, it is proved that Chungkookjang can be made in the mixed grains. Antioxidant activities of mixed fermented grains dissolved in ethanol or methanol (0.2 and 1 %) increased depending on their concentrations. Antioxidant activities were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH). One % of powder Chungkookjang dissolved in methanol showed highest antioxidant activity. Systolic blood pressure of hypertensive volunteers who took 20 g of mixed fermented powder decreased on average by 10 mmHg in 2 h. Preference of mixed fermented soybean containing barley, wormwood, sea tangle to fermented soybean was demonstrated by t-test analysis. Mixed fermented grains can be developed as a functional food to lower hypertension.

• Microbiology and Biotechnology Letters
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• v.20 no.1
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• pp.85-90
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• 1992

Rice bran was employed as a main medium component for ethanol fermentation by Saccharomyces species. Among the several strains of .Saccharomyces yeasts. S. cerevisiae IF0 2346 was selected as the hest strain in view of the interest in the production of ethanol and amino acids. It was found that S. cerevisiae IF0 2346 showed $3\times 10^8$cells/d and 4.7% (v/v) ethanol production after 72 hr cultivation. Although total amount of free amino acids was decreased from 1.099 mg/l to 829 mg/l during the fermentation, glutamic acid. histidine, and isoleucine were increased considerably. With the supplement of 5% glucose to the ferrnentation medium, both ethanol and amino acid production were increased up to 134% and 264%, respectively. compared to the control case. Glutamic. acid, leucine, alanine. phenylalanint:, and valine were the major amino acids in the fermentation broth.