• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.688-691
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• 2000

Ferritin, an iron-storage protein, is found in bacteria and some animal tissues such as liver, spleen, and bone marrow. It is more effective and causes less side reactions than the traditional ferrous sulfate, and thus has been used primarily to treat iron deficiency in pregnancy anaemia. Currently, the ferritin extracted from the bovine and equine spleens are sold as a commercial product. Its market is estimated as several hundreds of million US dollars. However, because of the recent warnings against the viral diseases of animal origins such as mad cow disease, a safer ferritin is sought after. Our research team has successfully developed a production process for recombinant human ferritin. Its expression titer from yeast is high enough to be economically viable, and its particle formation characteristics are as effective as well.

• 한국식품저장유통학회지
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• 제3권2호
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• pp.171-178
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• 1996

This study was carried out for the purpose of improving the persimmon vinegar. The acetic acid bacteria strain JST-3, using acetic acid fermentation was isolated from the traditional persimmon vinegar. The optimum conditions for high yield of acetic acid were studied in the shaking bath. Acetic acid bacteria was cultured at 3$0^{\circ}C$ for 4 days and transferred to persimmon alcoholic juice for acetic acid fermentation. The optimum initial acidity for acetic acrid fermentation was 1%(w/v) and the addition of glucose or yeast extract was observed to produce relatively low yield of acetic acid. Succinic and acetic acid were major organic acid in the persimmon vinegar, The contents of lactic acid which was known to increase off-flavor were very low. Sensory evaluation revealed that the persimmon vinegar prepared in this study was superior to two commercial ones in the aroma and taste.

• 한국식품영양학회지
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• 제13권2호
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• pp.158-163
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• 2000

Killer yeast, Hansenular capsulata S-13 were treated with heat, ethylmethane sulfonate and N-methyl-n'-nitro-n-nitrosoguanidine and a mutant(S13-E1), showing 2-fold higher killer toxin activity than that of parent strain to killer sensitive strain, Saccharomyces cerevisiae ATCC 38026 was obtained. Hansenular capsulata S13-E1 showed strong killer toxin activity to Saccharmyces mellis and Saccharomyces sal년 and four strains of gas-producing yeasts from traditional Doenjang and Kochujang. The culture condition for killer toxin production by Hansenular capsulata S13-E1 was optimized to be 1.0% potato extract, each 0.5% of peptone and glucose, and 0.025% MgSO4 with initial pH 4.5 at 3$0^{\circ}C$ and 36 hr of batch cultivation.

• 동아시아식생활학회지
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• 제14권4호
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• pp.379-386
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• 2004

Jeung-Pyun is a traditional Korean fermented rice cake leavened by yeast. To develop a functional Jeung-Pyun, mulberry leaf(ML) were added to the rice at the levels of 0, 2, 4, 6, 8%, respectively. Physicochemical, sensory, texture and surface characteristics of Jeung-Pyun were examined. The specific volumes of all the Jeung-Pyun's with ML were significantly lower than that of control(0% ML) and 4% ML sample showed the highest volume among them. The pH of ML Jeung-Pyun batters decreased with fermentation time. Overall quality of Jeung-Pyun with ML obtained lower value than the control. Among the texture properties measured with rheometer, hardness, cohesiveness, gumminess and brittleness of ML Jeung-Pyun decreased according to the amount ML added and springiness was not significantly different. The surface structure by SEM showed that Jeung-Pyun added with 4% ML had the largest and the most uniform air cells. In conclusion, the most acceptable concentrations of ML on the basis of overall quality in sensory evaluation and physicochemical characteristics were 2% or 4%.

• 동아시아식생활학회지
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• 제2권1호
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• pp.17-33
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• 1992

Information about processing method of Kwahaju can get from the 41 kinds classical literature traditional yakju. The contents of those classical literature consist of sixty items about Kwahaju, number of art-less-brewed alcoholics and compounded alcoholics. Interpreted content was classified and analyzed. Selected 40 items, about Kwahaju among previous 60 items, compounded brewages, were distributed into two groups of alcoholics ; Seoul Kwahaju and Kimchun Kwahaju. Both group of alcoholics, grunded on the periodical conversion of processing method through four centuries were set one thing to another and analyzed. The materials used for Kwahaju, compounded alcoholics, were waxy rice mainley, regular rice, yeast(Nuruk), wheat, barley seedings and Soju, Kwahaju, usually, is brewed for worm or hot season and store up the alcoholics for summer. It should be reminded to be durable alcoholics, not soon pureficated out or needing repair.

• Applied Biological Chemistry
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• 제48권3호
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• pp.228-232
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• 2005

Saccharomyces cerevisiae CY 균주에 의한 phytase의 생성은 진탕배양인 경우가 정치배양에 비하여 약 2배의 생성도를 보였다. CY 균주의 phytase는 세포내 효소활성이 세포외 효소활성에 비하여 약 3-4배 높게 나타났으나, 포도당이 1%로 저농도로 첨가된 배지에서는 세포내 효소활성과 세포외 효소활성의 분포비율이 1 : 1 정도로 유사한 비율로 나타났다. 세포내외로 생성된 총 phytase 활성은 포도당의 첨가농도에 상관없이 대략 1,000 mU/ml에 이르렀으며, 건조균체당 효소활성은 지수성장 말기에 170-190 mU/mg-DCW 범위에서 최대활성을 보였다. CY 균주의 세포내 효소의 최적 반응pH는 3.5이었으며, 최적 반응 온도는 $37-40^{\circ}C$이었다. 배양액에 존재하는 phytate는 성장하는 CY 균주에 의하여 배양 36시간째 4.3 mM phytate의 약 95%가 분해되었으며, 0.4 mg-DCW/ml의 균체농도를 갖는 현탁균체 반응액에서는 분해반응 12시간째 phytate의 약 90% 이상이 효율적으로 분해되었다.

• Fisheries and Aquatic Sciences
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• 제14권3호
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• pp.192-197
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• 2011

The objective of this study was to select an effective microbial strain to improve the functional qualities of Eisenia bicyclis water extract by fermentation. For this purpose, several microorganisms isolated from traditional Korean fermented foods were inoculated and cultivated in E. bicyclis water extract. Ultimately, yeast strain YM-1 was selected for further study based on its total phenolic compound (TP) content and antioxidant activity, which were enhanced by microbial fermentation. The extract fermented by YM-1 exhibited a superior TP content and 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity compared to extracts fermented by other microbes. The highest TP content and DPPH radical scavenging activity were observed after one day of YM-1 fermentation. Yeast strain YM-1 was identified as Candida utilis based on an analysis of its physiological characteristics. During fermentation of the extract by C. utilis YM-1, no significant difference was observed in the proximate composition, including moisture, crude lipid, crude protein, and crude ash. Fermentation by C. utilis YM-1 resulted in enhanced biological activity, including increases in the TP content and antioxidant activity. Thus, fermentation by C. utilis YM-1 is an attractive strategy for developing value-added food ingredients.

• 생명과학회지
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• 제14권5호
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• pp.815-820
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• 2004

본 연구에서 미생물유래의 종양 예방 및 억제제 개발을 목적으로 우리나라 전통 발효식품인 젓갈에서 항암 활성이 우수한 미생물을 분리, 동정 하였다. 젓갈로부터 항암물질을 생산하는 균주 SW-1을 분리하여 형태학적, 생리학적 특성을 검토한 결과, 본 균주는 Bacillus subtillis SW-1으로 동정되었다. 본 균주로부터 항암물질은 실험에 사용한 두가지의 암세포에 강한 활성을 나타내었다. 그 중에서 폐암 세포인 A549에 가장 강한 활성을 나타내었다. 항암물질 생산을 위한 최적 배양조건을 검토한 결과, 3.0% soluble starch, 1.0% yeast extract 였다. 무기염의 경우는 활성에는 그다지 영향을 미치지 않았다. 배지의 초기 pH 및 배양온도에 따른 항암물질의 생산성을 검토한 결과 초기 pH 5.0배양온도 3$0^{\circ}C$에서 25시 간배양 했을 때 최대 활성을 보였다. Chromosomal DNA단편화 실험에서 Bacillus subtilis SW-1의 배양상등액을 처리했을 때 DNA가 사닥다리모양으로 분해되는 Apoptosis(계획된 세포죽임)를 일으키는 것으로 확인되었다. 이 미생물이 생성하는 물질을 현재 HPLC, GC등을 이용하여 분리 중에 있으며 현재까지의 결과로는 당 중합체 인 것으로 분석된다.

• 한국축산식품학회지
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• 제33권3호
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• pp.325-330
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• 2013

Kefir is traditional fermented milk produced by various lactic acid bacteria (LAB) and yeast, which produce lactic acid, ethanol, carbon dioxide, and other flavor compounds. The purpose of this study was to evaluate the effects of different commercial oligosaccharides, such as maltotriose, fructooligosaccharide (FOS), galactooligosaccharide (GOS), and isomaltooligosaccharide (IMO), on the fermentation properties of kefir. First, we determined the acidification kinetic parameters, such as $V_{max}$, $t_{max}$(h), $t_{pH5.0}$(h), and $t_f$(h) of fermented milk supplemented with 4% (w/w) of different oligosaccharides. The probiotic survival and chemical composition (pH, organic acids profile, and ethanol content) of kefir during fermentation were also measured. Compared to control fermentation, all oligosaccharides increased acidification rate and reduced the time to complete fermentation (pH 4.7). The addition of FOS, in particular, resulted in the lowest $t_f$(h) and the highest populations of LAB and yeast during fermentation. All oligosaccharides increased ethanol production during fermentation. Further, significant differences were observed in the formation rates of six organic acids during fermentation. This study provided comparative data on the properties of commercial oligosaccharides for kefir manufacturing. Consequently, FOS especially had the potential for adequate and effective oligosaccharides in commercial kefir for the improvement of cost- and time-effectiveness.

• 한국수산과학회지
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• 제55권6호
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• pp.769-776
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• 2022

As an aquatic plant, the lotus leaf Nelumbo nucifera is rich in polyphenols, carotenoids, and flavonoids. We analyzed the chemical (pH, acidity, sugar, alcohol), microbiological (lactic acid bacteria, yeast), and antioxidant activity of Makgeolli supplemented with 5% and 10% lotus leaf (ll) during fermentation for 7 days. The pH of the non-additive group (control) was 3.10-6.03, that of the 5% added group was 3.17-5.77, and that of the 10% added group was 3.27-5.70, which decreased significantly (P<0.05) as the fermentation time elapsed. The acidity and sugar content were 1.89-2.12% and 9.10-12.90 Brix, respectively, which were significantly higher (P<0.05) as the amount of added ll increased. The alcohol content was 5.90-7.20% and was the highest on the seventh day of fermentation. The lactic acid bacteria was 6.07-7.17 log CFU/mL, which was higher in ll Makgeolli. Yeast increased until day 3 and then decreased to 3.27-5.86 log CFU/mL. DPPH (1,1-diphenyl-2-picrylhdrazyl) and ABTS [2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging activities were higher in ll Makgeolli (DPPH 68.72-81.48%, ABTS 90.71-91.67%). In this study, the commercialization potential of ll Makgeolli was expanded by enhancing the quality and antioxidant function of Makgeolli added with ll.