• 한국미생물·생명공학회지
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• 제50권1호
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• pp.81-88
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• 2022

Acetic acid bacteria (AAB) are versatile organisms involved in the production of variety of fermented foods, such as vinegar and kombucha, and products of biotechnological relevance, such as bacterial cellulose. In the present study, Malatya apricot, a variety with protected designation of origin (PDO), and vinegar samples produced using various fruits were used to isolate AAB. The 19 AAB isolates obtained were typed using (GTG)5 fingerprinting, and the ones selected were identified by sequencing either 16S rDNA alone or in combination with 16S-23S rRNA internal transcribed spacer region or ligA gene. While all apricot isolates (n = 10) were Gluconobacter cerinus, vinegar isolates (n = 9) were composed of Komagataeibacter saccharivorans, Acetobacter syzygii, and possible two new species of AAB, Komagataeibacter sp., and Gluconobacter sp. (GTG)5 fingerprinting showed the presence of several genotypes of G. cerinus in the apricot samples. Screening for some technologically relevant properties, including thermotolerance, ethanol tolerance, and cellulose production capability, showed that all Komagataeibacter and some Gluconobacter isolates could tolerate the temperature of 35℃, and that vinegar isolates could tolerate up to 8% ethanol. One isolate, Komagataeibacter sp. GUS3 produced bacterial cellulose (1 g/l) and has the potential to be used for cellulose production.

• 생명과학회지
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• 제19권10호
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• pp.1432-1437
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• 2009

BC 합성능이 우수하며, 진탕배양에서도 BC를 생산할 수 있는 능력이 있음이 확인된 Aectobacter sp. V6로부터 BC 생산을 위한 당밀 전처리 조건을 검토하였으며, 생산된 BC의 물리화학적 특성을 검토하였다. 당밀을 배지성분으로 사용하기 위해 전처리를 실시한 결과, 1%의 TP가 BC 생산에 가장 효율적이었다. 전처리한 당밀배지를 이용하여 정치 및 진탕배양에서 생산된 BC의 물리화학적 특성을 조사한 결과, 모든 BC는 유화능이 있었으나 유화 안정능은 낮았다. 또한 모든 BC에서 높은 수분 보유능이 나타났으며, 특히 정치배양에서 생산된 BC는 $\alpha$-cellulose보다 14배 이상 높았다. BC의 점도는 모두 $\alpha$-cellulose보다 높았으며, 점도계 회전속도의 증가에 따라 급격히 감소하였다. FT-IR을 통한 조성 분석에서 BC는 식물성 셀룰로 오스와 차이가 없었으며, XRD를 통한 결정성 분석에서는 모든 BC가 결정성을 나타내었다. BC의 미세구조를 조사한 결과, 모든 BC가 미세망상구조로 이루어져 있었는데, 이로 인해 BC는 식물성 셀룰로오스와는 달리 독특한 물성을 가지는 것으로 판단되었다. 또한 정치배양에서 생산된 BC는 진탕배양에서 생산된 것보다 셀룰로오스 미세섬유가 조밀하게 얽혀있음을 알 수 있었다.

• 한국식품영양과학회지
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• 제43권2호
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• pp.250-257
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• 2014

폐자원인 감귤 미숙과를 이용한 식초를 개발하기 위하여 초산 생성능이 우수한 균주를 분리 동정하였고, 감귤 미숙과를 발효하여 식초를 제조한 후 품질 특성, 총 페놀 및 총 플라보노이드 함량, 항산화 활성을 측정하였다. 감귤슬러지 자연 발효물로부터 5개 균주를 분리하였으며, 그중 초산균으로 Acetobacter fabarum(A. sp. RIC I)과 A. pomorum(A. sp. RIC II, V)이 동정되었는데, A. sp. RIC V가 초산 생성능이 가장 우수하여 감귤 미숙과즙의 초산발효 균주로 선정하였다. A. sp. RIC V를 이용하여 감귤 미숙과즙의 첨가비율을 30, 35, 40%로 달리하였을 때 발효 13일 후 산도는 각각 5.38, 5.38, 5.32%, 발효 효율은 각각 73, 72, 70%이었다. 미숙과즙 초산발효 시 산도가 5%에 도달하는 기간은 과즙 첨가비율이 30%일 때는 11일, 35와 40%일 때는 9일이었다. 유리당으로 fructose와 glucose는 과즙 첨가비율이 높을수록 높은 함량을 나타내었으나 sucrose는 과즙 첨가비율과 관계없이 모두 비슷하였다. 유기산의 경우에는 미숙과 과즙의 첨가비율이 높을수록 acetic acid를 비롯한 총 유기산이 증가하였다. 감귤 미숙과 식초와 완숙과 식초의 총 페놀 함량은 각각 1,546.6과 $230.9{\mu}g$ GAE/mL이었고, 총 플라보노이드 함량은 각각 1,004.7과 $175.1{\mu}g$ QE/mL이었다. DPPH 자유라디칼 소거활성은 감귤 미숙과와 완숙과 식초가 각각 29%와 5%이었고, ABTS 소거능은 각각 62.0%와 17.9%였다. SOA 소거활성은 감귤 미숙과 식초와 완숙과 식초가 각각 60.9%와 41.7%이었고, XO 억제활성은 각각 32.5%와 5%이었다. 이상의 결과로부터 A. sp. RIC V를 이용하여 감귤 미숙과즙을 35와 40% 첨가하였을 때 초산발효가 가장 우수하였으며, 감귤 미숙과 식초는 높은 총 페놀과 총 플라보노이드 함량으로 인하여 높은 항산화 활성을 나타내어 기능성 식초로 활용할 수 있을 것이다.

• Journal of Microbiology and Biotechnology
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• 제20권9호
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• pp.1322-1330
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• 2010

Three types of nuruk were made from rice, wheat, and a rice-glasswort (6:4) mixture. Nuruk, makgeolli, and vinegar were manufactured with rice nuruk (RN), wheat nuruk (WN), and rice-glasswort nuruk (RGN). The variable region of 18S or 16S rDNA amplified with genomic DNA extracted directly from nuruk-, makgeolli-, and vinegar-making cultures was analyzed via temperature gradient gel electrophoresis (TGGE). The sequence of the 18S rDNA variable region extracted from the TGGE gel for nuruk was 99% homologous with Aspergillus sp. and that for the makgeolli-making culture was 99% homologous with Saccharomyces sp. and Saccharomycodes sp. The sequence of the 16S rDNA variable region extracted from TGGE gel for the vinegar-making culture was 98% homologous, primarily with the Acetobacter sp. The eukaryotic and prokaryotic diversities in the nuruk-, makgeolli-, and vinegar-making cultures was not significantly altered by the addition of glasswort. Prokaryotic diversity was higher than eukaryotic diversity in the nuruk, but eukaryotic diversity was higher than prokaryotic diversity in the makgeolli-making culture, on the basis of the TGGE patterns. No 18S rDNA was amplified from the DNA extracted from the vinegar-making culture. The diversity of the microbial community in the process from nuruk to vinegar was slightly affected by the type of raw material utilized for nuruk-making. The saccharifying activity and ethanol productivity of nuruk, polyphenol content in makgeolli, and acetic acid and polyphenol content in the vinegar were increased as a result of the addition of glasswort. In conclusion, the glasswort may be not simply an activator for the growth of microorganisms during the fermentation of nuruk, makgeolli, or vinegar, but also a nutritional supplement that improves the quality of vinegar.

• Journal of Life Science
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• 제9권1호
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• pp.69-80
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• 1999

Some trials to alter the structure of extracellular polysaccharides by means of biotransformation and microbial modification have been reported. Seaweed alginate was acetylated by intact and resting cells of Pseudomonas syringae ATCC 19304. Glucose analogs such as 3-O-methyl-D-glucose used as sole carbon sources was directly incorporated into curdlan by agrobacterium sp. ATCC 31749. The 2-amino-2-deoxy-D-glucose (glucosamine)and 2-acetamido-2-deoxy-D-glucose (N-acetylglucosamine) were incorporated into microbial cellulose by Acetobacter xylinum ATCC 10245. The changed monomeric composition in pullulan by Aureobasidium pullulans ATCC 42023 as well as zooglan by Zoogoea ramigera ATCC 25935 was another effect of glucose analogs used a carbon source. There was no effect of glucose analogs found in polysacharide-7 (PS-7) produced by Beijerinckia indica. ATCC 21423.

• 한국식품영양과학회지
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• 제28권1호
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• pp.53-60
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• 1999

Possibility of utilization of fig as a source of vinegar was tested. Alcohol fermentation was conducted by inoculation of Saccharomyces bayanus into fig juice. After 5 days of fermentation at 27oC, fig wine with alcohol content of 13.6%. Then fig vinegar was produced by cultivation of Acetobacter sp. E which was isolated from fig vinegar. Optimum concentration of alcohol, starter content and fermentation temperature for the acid production were 8~9%, 5% and 27~30oC, respectively. More acetic acid was produced by adding 0.5% of yeast extract and 0.01% of Ca pantothenate. Adjustment pH of culture broth with acetic acid and shaking cultivation method were not effective in higher yield of acid production. Addition of sulfite up to 50 ppm did not inhibit for acetic acid fermentation. Addition of 1% bentonite or 1% kakishibu was more effective for the clarification of fig vinegar than any other clarifying agents tested. During aging and racking, acidity, absorbance and tannin content of fig vinegar decreased, while redness and yellowness increased. Aged and racked fig vinegar showed higher sensory score than non aged one in the aspects of color and overall acceptability.

• 동아시아식생활학회지
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• 제7권3호
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• pp.301-307
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• 1997

유자의 이용가치를 향상시키기 의하여 유자과즙을 이용하여 식초를 제조하고 그 특성을 조사한 결과는 다음과 같다. 유자식초제조의 최적 발효조건은 공시균주로서 Acetobactor sp. PA97, 온도는 3$0^{\circ}C$ 초기 알코올농도는 8% 및 초발산도는 1.5%였다. 유자과즙 농도별 초산발효에서 초산의 생성량은 과즙의 농도가 낮을수록 높게 나타났으며, 부영양원 첨가구가 무첨가구보다 높았다. 부영양원이 첨가되고 유자과즙이 10, 20 및 30%가 첨가된 구에서 총산은 5.42, 5.36 및 5.04%이었고, 순수 초산생성율은 각각 52.69, 45.25 및 35.10%이었다. 잔류알코올은 부영양원 무첨가구가 첨가구보다 많았다. 관능검사 결과 유자원액의 희석비는 30%가 종합적인 점수에서 가장 높아 유자식초 제조시 가장 적당한 희석배수임을 알 수 있었다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.623-625
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• 2000

Bacteriocin을 생산하는 유산균을 김치에서 분리하였고 Lactococcus latis subsp. lactis로 확인 되었으며 bacteriocin의 최대생산조건은 $30^{\circ}C$, 6시간으로 다양한 유산균 및 Pseudomonas synsantha, Acetobacter aceti의 생육을 저해하였고 여러 peptidases에 의해 불활성화되었다. 또한 다양한 범위의 pH와 열처리에 안정하였고 SDS-PAGE결과 약 8 Kda으로 확인되었다.

• 한국미생물·생명공학회지
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• 제50권3호
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• pp.404-413
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• 2022

The process of manufacturing craft beer involves a wide variety of spontaneous microorganisms, acting in different stages of the brewing process, that contribute to the distinctive characteristics of each style. The objective of this work was to compare the structure of microbial communities associated with two different craft beer styles (Doppelbock and Märzen lagers), at a late maturation stage, and to identify discriminative, or style-specific taxa. Bacterial and fungal microbial communities were analyzed by Illumina sequencing of 16S rRNA gene of prokaryotes and the ITS 2 spacer of fungi (eukaryotes). Fungal communities in maturating beer were dominated by the yeast Dekkera, and by lactic acid (Lactobacillus and Pediococcus) and acetic acid (Acetobacter) bacteria. The Doppelbock barrels presented more rich and diverse fungal communities. The Märzen barrels were more variable in terms of structure and composition of fungal and bacterial communities, with occurrence of exclusive taxa of fungi (Aspergillus sp.) and bacteria (L. kimchicus). Minority bacterial taxa, differently represented in the microbiome of each barrel, may underlie the variability between barrels and ultimately, the distinctive traits of each style. The composition of the microbial communities indicates that in addition to differences related to upstream stages of the brewing process, the contact with the wood barrels may contribute to the definition of style-specific microbiological traits.

• 한국환경과학회지
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• 제23권5호
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• pp.895-902
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• 2014

Bacterial cellulose (BC) has played important role as new functional material for food industry and industrial products based on its unique properties. The interest in BC from static cultures has increased steadily in recent years because of its potential for use in medicine and cosmetics. In this study, we investigated culture condition for BC production by Acetobacter sp. F15 in static culture. The strain F15, which was isolated from decayed fruit, was selected on the basis of BC thickness. The optimal medium compositions for BC production were glucose 7%, soytone 12%, $K_2HPO_4$ 0.2%, $NaH_2PO_4{\cdot}_2H_2O$ 0.2%, lactic acid 0.05% and ethanol 0.3%, respectively. The strain F15 was able to produce BC at $26^{\circ}C-36^{\circ}C$ with a maximum at $32^{\circ}C$. BC production occurred at pH 4.5-8 with a maximum at pH 6.5. Under these conditions, a maximum BC thickness of 12.15 mm was achieved after 9 days of cultivation; this value was about 2.3-fold higher than the thickness in basic medium. Scanning electron micrographs showed that BC from the optimal medium was more compact than plant cellulose and was reticulated structure consisting of ultrafine cellulose fibrils. BC from the optimal medium was found to be of cellulose type I, the same as typical native cellulose.