Abstract
Benzoylformate was converted to benzaldehyde by whole cell enzyme from Pseudomonas putida KCTC 1751. We investigated the effect of the composition of the growth medium on th accumulation of benzoylformate decarboxylase in the microbial cell. We prepared a calcium alginate capsule containing Pseudomonas putida cells to develop a reusable whole cell enzyme. Pseudomonas putida cells were inoculated in the capsule and cultured in M1 medium for 1 day followed by cultivation in M3 medium for 3 days. The dry cell density reached 77.75 g/L on the basis of the inner volume of the capsule. The specific activity of encapsulated whole cell benzoylformate decarboxylase was half as high as that of free whole cell enzyme. The activity of encapsulated whole cell benzoylformate decarboxylase was half as high as that of free whole cell enzyme. The activity of encapsulated whole cell benzoylformate decarboxylase decreased 20 % after use for 20 batches and 40% after use for 30 batches. The dry cell density reduced about 10 % after 30 trials.
Mandelate pathway를 거치는 Pseudomonas putida(KCTC 1751)의 전세포 benzoylformate dcarboxylase를 이용하여 benzoylformate를 benzaldehyde로 변환하였고 성장배지의 조성이 cell내부에 축적되는 benzoylformate dcarboxylase의 양에 미치는 영향을 조사하였다. 전세포효소의 재사용을 위하여 calcumalginate 캡슐 고정회법을 이용하여 캡슐고정화 Pseudomonas putida를 제조하였다. 캡슐 고정화 미생물을 M3배지에서 3일간 배양한 후 M1배지에서 1일간 배양한 결과 77.75g/L의 미생물 건조중량을 얻었다. 캡슐 고정화 전세포 benzoyltormate decarboxylase의 비활생도는 자유배양에 의한 전세포효소의 비활성도에 비해 약 1/2값을 나타내었으며 캡슐 고정화 전세포 benzoyltormate decarboxylase를 20회 재사용시 20%의 실활을 보였으며 캡슐 재사용 30회 이후 미생물의 건조중량은 약 10% 감소를 보였다.