Effects of spray drying temperature and additives on the stability of serine alkaline protease powders

In this study, after production by recombinant Bacillus subtilis (BGSC-1A751), carrying pHV1431:: subc gene in the complex medium and separation of solids from the fermentation broth, serine alkaline protease (SAP) was dried in order to investigate the stabilization during spray drying and subsequent storage. The effect of air inlet temperature of the spray dryer between T = 70 and 130 degrees C and the effect of protective additives, glucose and maltodextrin, at 0-2% (w/v) on SAP activity during spray drying and storage stability of obtained SAP powders at 4 degrees C for a long period (6 months) were evaluated. Increasing drying air inlet temperature generally resulted in an increase in activity loss; moreover, higher absorbance peaks observed at wave number 1061 cm(-1) of the IR spectrums when drying temperature is increased indicates the structural change in the SAP molecule. In most cases presence of additives provided higher activities both after drying and during storage period compared to no additive case. Drying the enzyme with 1% (w/v) glucose at T =110 degrees C resulted in the highest enzyme activity after drying and storage processes.


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The effects of the controlled and uncontrolled pH conditions, as well as of the value of initial pH in the range of 7-7.5, on serine alkaline protease (SAP) production by Bacillus licheniformis were investigated on a defined medium with the single carbon source glucose in batch bioreactors. Besides uncontrolled pH operations, growth phase, production phase, and entire process control strategies were also applied. The concentrations of the product (SAP) and by-products, i.e. neutral protease, amylase, amino ...
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Citation Formats
A. Namaldi, P. Çalık, and Y. Uludağ, “Effects of spray drying temperature and additives on the stability of serine alkaline protease powders,” DRYING TECHNOLOGY, pp. 1495–1500, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42617.