ISSN:
1432-0614
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Summary The repeated batch and continuous operations for transphosphatidylation reaction were carried out for phosphatidylglycerol (PG) synthesis from phosphatidylcholine (PC) with the help of immobilized cabbage phospholipase D (PLD) in the presence of glycerol. The biphasic reaction system was used which included the aqueous phase containing immobilized PLD along with high concentrations of glycerol (30%–50%) and buffer, whereas the main part of substrate (PC) and products (mainly PG) formed were in the organic phase (diethyl ether). Octyl-Sepharose CL-4B having a hydrophobic octyl group was chosen for the PLD immobilization. Both immobilization yield and activity yield of immobilized enzyme were 100%. The effects of solvents, temperature and glycerol concentrations on the immobilized PLD were examined. Repeated batch conversion of PC (15 g/l) to PG was examined with the immobilized PLD in 30% glycerol. In all five batch cycles examined, 100% selectivity was obtained and there was no significant decrease in the fractional conversion of PC to PG (98%–99%) in the first three batch cycles. In the cases of a packed-bed reactor (PBR) and a continuous stirred-tank reactor (CSTR) used for continuous synthesis of PG with the immobilized PLD, the operational stabilities of the immobilized enzyme were almost the same (half life=14 h at 30°C) when purified PC was used, while in the case of partially purified PC in CSTR the half life increased more than five times.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00251937
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