Naslov
Biooxidation kinetics in reaction systems of low water activity

Autori
Pervan, Zrinka ; Mihaljević, Krešimir ; Bošnjak, Marjan ; Matošić, Srećko

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Book of Abstracts / Kuenen, G. - Budimpešta : Hungary Biochemical Society, 1997

Skup
8th European Congress on Biotechnology

Mjesto i datum
Budimpešta, Mađarska, 1997

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
biooxidation kinetics; D- glucose

Sažetak
Kinetics of D-glucose and S-sorbitol oxidation catalised by biocatalytic system of Gluconobacter suboxydans S-22 in reaction media of low water activity werw studed. The shake flask cultivation experiments at different temperatures were perfomed aplly reaction systems with intact and designated microbial cells suspended in sterile water solutions of different D-glucose and D-sorbitol concentrations. Values of input parametars adequaly reflected on experimental results. The increase in substrate concentrations caused an adequate decrease of volumetric oxygen transfer rate coefficient (Kla). Specific biocatalytic activity of washed whole intact cells was much higher than that of corresponding amount of disintegrated cells, only in the substance concentration range below 500 g/L. In general, specific biocatalytic activites were decreasing with increasing substrate concentration. However, the fall down of activity of intact cells as a function of substrate concentration appeard to be of sigmoidal form, while that of disrupted cells showed to be appoximately linear. A lower temperature (30oC) was more convinient for reaction systems of lower substrate concentration(100 g/L), while a higher temperature (37oC) showed to be more favourable for reaction systems of higher substrate concentrations.Data agree expetation, if taking into account findings of other (1) for other reaction systems.Based on the obtained results and our previous observation (2), it could be concluded that mass transfer phenomena play an important role in biooxidation kinetics.Findings of this work support our previous observation and suggest the application of higher biooxidation temperature, in cases when water activity in reaction systems falls down below 0.4 (e.g. when applyng high yielding prolonged fed batch culture or two-compartment fed bach culture).

Izvorni jezik
Engleski

Znanstvena područja
Prehrambena tehnologija

POVEZANOST RADA