• Journal of Microbiology and Biotechnology
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• 제3권2호
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• pp.108-114
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• 1993

A new strain of acidophilic, acetogenic bacterium, Acetobacter sp. strain HA was isolated by selective enrichment from the traditionally fermented rice wine vinegar in Korea. It was a gram-negative, non-motile short rod and oxidized acetate and lactate. The optimal temperature and pH for growth were $28^{\circ}C$ and 4.0, respectively. The strain HA differed from other Acetobacter species by growing well on methanol, xylitol, inositol, dulcitol, D-xylose, L-arabinose, and D-mannose as sole sources of carbon and energy. The isolated strain HA did not produce $\gamma$-pyrones from glucose and did not produce ketone bodies from glycerol. The quinone system used in this study was an ubiquinone-9 isoprene unit. The guanine-plus-cytosine content of the DNA was 50.7 mol%, and the major cellular fatty acids were $C_{18:1} and C_{16:0}$.

• 미생물학회지
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• 제32권1호
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• pp.78-83
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• 1994

초산 생성 균주인 Acetobacter sp. HA로부터 membrane-bound alcohol dehydrogenase(ADH)를 분리 정제하였다. 세포막 분획과 세포막에서 효소의 용출 그리고 크로마토그라피 방법 등을 적용하여 수율 35%, 153배 정제된 효소를 획득하였다. 정제된 효소의 분자량은 330,000 dalton이었으며, 각각 분자량 79,000과 49,000 그리고 45,000 dalton을 가진 세 종류의 subunit로 이루어져 있었다. 그리고 흡수 스펙트럼의 분석 결과 본 효소에는 cytochrome c가 존재함을 확인할 수 있었다. 본 효소는 메탄올을 제외한 1차 지방족 알코올을 기질로 이용할 수 있었으며, formaldehyde, acetaldehyde 그리고 glutaraldehyde의 경우에도 다소간 기질로 이용될 수 있었다. 본 효소의 에탄올에 대한 $K_m$값은 1.38mM이었으며, 최적 pH와 온도는 각각 5.0~6.0과 32${\circ}C$이었다. 본 효소의 활성은 $V_2O_5$와 $ZnCl_2,\; NiCl_2$같은 금속 이온에 의하여 저해되었다.

• Journal of Microbiology and Biotechnology
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• 제4권3호
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• pp.165-170
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• 1994

An efficient and convenient method of introducing transposable elements into acetic acid bacteria was developed by the method of conjugal transfer. The ampicillin-resistant strain, Acetobacter sp. HA, was selected to be conjugated with two E. coli strains, WA803 containing pGS9 and AC8001 harboring pJB4JI. The Tn5 containing suicide vector pGS9 or pJB4JI, was transferred from E. coli to Acetobacter sp. HA and kanamycin-ampicillin-resistant transconjugants obtained at high frequencies. The conjugal frequencies of pGS9 and pJB4JI were 6.20$\times$$l0^{-1} and 2.79$\times$l0{-1}$ per recipient, respectively. The transfer method was applied on four different strains of Acetobacter. The conjugal transfer frequencies ranged from 2.00$\times$$l0^{-2} to 4.45$\times$l0^{-8}$ per recipient in the three strains. Some transconjugants tested were found to contain Tn5 DNA in their genomes and this was confirmed by Southem blot analysis. This is the first study which shows that Tn5 mutagenesis can be applied to successfully isolate mutants of Acetobacter genus.

• 미생물학회지
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• 제45권3호
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• pp.275-280
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• 2009

한국 전통발효식초로부터 분리된 Acetobacter sp. V6에 의한 bacterial cellulose (BC) 생산을 위한 최적 배지조성을 정치배양을 이용하여 조사한 후, 생성된 BC의 구조적 특성을 검토하였다. 탄소원으로 glucose 3%, 질소원으로 soytone 3%가 선정되었다. 또한 인산염은 $K_2HPO_4$ 0.8%였으며, 추가로 첨가한 $NaH_2PO_4$와 $KH_2PO_4$는 BC 생산 증가를 나타내지 못하였다. 보조탄소원으로 ethanol 0.4%에서 가장 높은 BC 생산성을 나타내었다. 최적 배지조성하에서 배양 8일만에 최대 44.7 g/$m^2$의 BC가 생산되었으며, 배양 8일경, BC pellicle의 두께는 약 1 cm였다. BC의 구조는 Fourier-transform infrared spectroscopy 및 X-ray diffractometer를 이용하여 조사하였다. 최적배지에서 생성된 BC는 전형적인 cellulose type I임을 알 수 있었으며, 식물성 셀룰로오스와 성분의 차이가 없었다. 또한 독특한 미세망상구조로 이루어져 있었고, 높은 결정성을 나타내어 식물유래 셀룰로오스와 다른 독특한 물성을 나타내는 것으로 추정되었다.

• 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.

• 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.

• 한국환경과학회지
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• 제20권7호
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• pp.899-905
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• 2011

In order to develop bacterial cellulose (BC) with antimicrobial activity against pathogenic microorganisms, silver and chitosan were incorporated into BC, respectively. Experiment results showed that antimicrobial activity against pathogenic microorganisms was improved with increasing silver concentration. Chitosan also showed a direct proportion between its concentration and antimicrobial activity. These results suggest that antimicrobial effects of BC using silver and chitosan are well proven to be effective. We also tested the stainability of BC with natural colorant for the application of food industry. Stainability of BC was enhanced with increasing natural colorant concentration. Decolorization of BC stained was observed by dipping it into distilled water with one hour-intervals. As a result, there was no significant difference. Combination of natural colorant-stainability and antibiosis of BC is expected to be useful in making colored antibiotic BC in various industrial application areas, considering its antimicrobial activity, high stainability and low decolorization tendency.

• KSBB Journal
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• 제32권3호
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• pp.238-244
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• 2017

Antioxidant activities of blackberry juice and aronia juice were enhanced when fermentation was performed by acetic acid bacteria. Acetobacter pasteurianus exhibited 19.84% improvement of antioxidant activity (from $198.12{\pm}2.03$ to $237.42{\pm}7.32{\mu}mol\;TE/g$) after 12 h fermentation of blackberry juice among four acetic acid bacteria. And A. pasteurianus sub sp. Pasteurianus exhibited 9.62% improvement of antioxidant activity (from $204.25{\pm}3.98$ to $223.89{\pm}5.52{\mu}mol\;TE/g$) after 12 h fermentation of aronia juice. Metabolites of blackberry juice were analyzed to investigate the enhancement of antioxidant activity before and after fermentation. As results, Quercetin 7-(rhamnosylglucoside), nicotinic acid adenine dinucleotide, and quercetin 3-O-(6"-acetyl-glucoside) were significantly increased after fermentation by A. pasteurianus.