TY - JOUR
T1 - Use of free and immobilized Pseudomonas putida cells for the reduction of a thiophene derivative in organic media
AU - Fernandes, P.
AU - Vidinha, P.
AU - Ferreira, T.
AU - Silvestre, H.
AU - Cabral, J. M.S.
AU - Prazeres, D. M.F.
PY - 2002/12/2
Y1 - 2002/12/2
N2 - An organic-aqueous two-liquid phase system was developed in order to perform the reduction of 3-thiophenecarboxaldeyde (3-TC) to 3-thiophenemethanol (3-TM), two intermediate logP compounds, using Pseudomonas putida S12 cells. Although, high bioconversion yields were observed in a bioconversion medium composed by Tris-HCl pH 8.5 buffer and n-octanol, adverse phase toxicity effects were observed following incubation periods in excess of 24h. Furthermore, a stable emulsion was formed in two-liquid phase system in the presence of free cells. This prevented effective separation of the biocatalyst and of the two-liquid phases. Whole cells were effectively entrapped in Ca-alginate beads, thus enhancing biocatalyst recovery. No shifts in the pH versus activity profile resulted from the immobilization. Successive batches were carried out with the immobilized biocatalyst, but a decrease in the specific activity was observed.
AB - An organic-aqueous two-liquid phase system was developed in order to perform the reduction of 3-thiophenecarboxaldeyde (3-TC) to 3-thiophenemethanol (3-TM), two intermediate logP compounds, using Pseudomonas putida S12 cells. Although, high bioconversion yields were observed in a bioconversion medium composed by Tris-HCl pH 8.5 buffer and n-octanol, adverse phase toxicity effects were observed following incubation periods in excess of 24h. Furthermore, a stable emulsion was formed in two-liquid phase system in the presence of free cells. This prevented effective separation of the biocatalyst and of the two-liquid phases. Whole cells were effectively entrapped in Ca-alginate beads, thus enhancing biocatalyst recovery. No shifts in the pH versus activity profile resulted from the immobilization. Successive batches were carried out with the immobilized biocatalyst, but a decrease in the specific activity was observed.
KW - Biocatalyst
KW - Pseudomonas putida
KW - Thiophene derivative
UR - http://www.scopus.com/inward/record.url?scp=0037010712&partnerID=8YFLogxK
U2 - 10.1016/S1381-1177(02)00186-8
DO - 10.1016/S1381-1177(02)00186-8
M3 - Article
AN - SCOPUS:0037010712
SN - 1381-1177
VL - 19-20
SP - 353
EP - 361
JO - Journal of Molecular Catalysis - B Enzymatic
JF - Journal of Molecular Catalysis - B Enzymatic
ER -