• KSBB Journal
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• 제15권6호
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• pp.670-672
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• 2000

Azotobacter vinelandii uwn는 배지에 짝수의 탄소원외에 홀수의 탄소원을 첨가했을 때 생분해성 고분자인 PHBV를 합성한다. 본 실험에서는 propionic acid와 valerie acid를 첨가 한 후 세포생장과 비생장속도를 관찰하였다. Propionic acid 농도가 1.0 -1.5 g/L, valerie acid 농도가 1.0 g/L일 때 세포 생장이 다른 농도에서보다 높았으며, 이때의 비생장속도는 각각 $0.183 hr^{-1}, 0.137 hr^{-1}$이었다. 그리고 이들 유기산을 각각 0 0.75 g/L, 0.5 g/L 혼합하여 배지중에 넣었을 때 비생장속도 는 유기산을 단독으로 첨가한 경우보다 높게 나타났다. 포도당 농도가 10~50 g/L 에서 실험한 결과 20 g/L 일 때 생장 속도가 가장 높았다.

• KSBB Journal
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• 제13권5호
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• pp.626-630
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• 1998

Ammonium limitation did not promote ply(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) production of Azotobacter vinelandii UWD. In acid phase, ammonium limitation during utilization of propionic acid and butyric acid led to 35% decrease in product yield. In glucose phase, both biomass yield and polymer yield decreased about 22% under ammonium limitation. However, in nitrogen-fixing culture glucose was consumed 25% faster and the final PHBV wt% decreased slightly. Under nitrogen limitation a portion of the carbon sources was used fro nitrogen fixation rather than biomass and polymer formation, resulting in a decrease in biomass yield and polymer yield.

• KSBB Journal
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• 제13권6호
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• pp.675-680
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• 1998

In both 7L and 20L fermentor experiments the level of dissolved oxygen (D.O) strongly affected growth and PHBV production of Azotobacter vinelandii UWD. A higher D.O. increased carbon substrate consumption rate and cell growth rate with a similar residual biomass production. However, a lower D.O. was a much better condition for PHBV production. In a 20L fermentor experiments controlled at 5% D.O. cell growth rate was about twice faster(0.555 hr-1 and 0.260 hr-1 at the acid and the glucose phase, respectively) with an equal amount(4.5 g/L) of residual biomass production. However, PHBV content in the cell(62.3 wt%) increased 17.3 times at 1% D.O.

• 한국미생물·생명공학회지
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• 제26권6호
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• pp.529-536
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• 1998

용존산소(D.O.) level은 유기산 및 포도당을 혼합한 배지에서 Azotobacter vinelandii UWD의 생장 및 생분해성 고분자(PHBV) 생성에 큰 영향을 주었다. 용존산소 level이 높은 경우(5% D.O.)는 낮은 경우(1% D.O.)에 비해 세포의 생장속도가 약 2배 증가하였으나 PHBV 생성은 D.O.가 낮은 경우 62.3 wt%로 D.O.가 높은 경우에 비해 약 17배 증가하였다. 그러나 B.O. level은 통기(aeration)에 의한 A. vinefandii UWD의 발효특성 연구에 적합한 기준이 아니었다. 공기공급속도를 고정하고 교반속도만을 변화시키는 통기법으로 산소전달속도를 감소시켰을 때 이 균주는 산소소모속도를 그에 따라 대응 감소시킴으써 겉보기 D.O.를 높게(5%) 유지할 수 있었고 이 때 생장이 느려지고 PHBV 양은 57.3 wt%로 증가하였다. 통기가 세포생장 및 PHBV 생성에 미치는 영향을 일관성 있게 설명할 수 있는 기준은 D.O. level이 아니라 산소전달속도였으며 비생장속도는 산소전달속도에 비례하여 증가하였고 PHBV 생산량은 산소전달속도에 반비례하였다.

• KSBB Journal
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• 제13권5호
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• pp.615-620
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• 1998

The readily fermentable carbon sources in swine were acetic acid, propionic acid and butyric acid at the average concentrations of 7.2 g/L, 2.2 g/L and 2.7 g/L, respectively. The swine waste also contained excess nitrogen and other mineral sources. In shake flask experiments, the optimal range of cell growth for Azotobacter vinelandii UWD were 1.0∼3.5 g/L of acetic acid, 0.7∼2.0 g/L of propionic acid and 0.5∼2.0 g/L of butyric acid. A mixture of these three acids simulating two times diluted swine waste supported the best cell growth but the amount of carbon sources was limited. In shake flask and fermentor experiments, an addition of 30 g/L of glucose increased the final cell dry weight 8 times while the final poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) concentration increased 86 times compared with using acid mixture only. A. vinelandii UWD preferred organic acids in the sequence of acetic acid, propionic acid, butyric acid, and valeric acid.

• Journal of Microbiology and Biotechnology
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• 제20권3호
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• pp.594-601
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• 2010

Azotobacter chroococcum H23 (CECT 4435), Azotobacter vinelandii UWD, and Azotobacter vinelandii (ATCC 12837), members of the family Pseudomonadaceae, were used to evaluate their capacity to grow and accumulate polyhydroxyalkanoates (PHAs) using two-phase olive mill wastewater (TPOMW, alpeorujo) diluted at different concentrations as the sole carbon source. The PHAs amounts (g/l) increased clearly when the TPOMW samples were previously digested under anaerobic conditions. The MNR analysis demonstrated that the bacterial strains formed only homopolymers containing $\beta$-hydroxybutyrate, either when grown in diluted TPOMW medium or diluted anaerobically digested TPOMW medium. COD values of the diluted anaerobically digested waste were measured before and after the aerobic PHA-storing phase, and a clear reduction (72%) was recorded after 72 h of incubation. The results obtained in this study suggest the perspectives for using these bacterial strains to produce PHAs from TPOMW, and in parallel, contribute efficiently to the bioremediation of this waste. This fact seems essential if bioplastics are to become competitive products.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.481-484
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• 2000