초록
<P><B>Graphical abstract</B></P><P><ce:figure id='fig0005'></ce:figure></P><P><B>Highlights</B></P><P>► High yield production of carbonyl compounds using microsome-bound AOx catalyses was established. ► The AOx catalyzed production of carbonyls was achieved in environmentally benign conditions. ► The microsome bound AOx was successfully immobilized in polyurethane foam matrix. ► The synthesis of industrially important <I>n</I>-heptanal was achieved by polyurethane foam immobilized AOx catalytic process. ► High operational stability of the immobilized enzyme was demonstrated.</P> <P><B>Abstract</B></P><P>High yield conversion of a wide range of alcohol substrates to their corresponding aldehydes was demonstrated using a microsomal alcohol oxidase (AOx) from <I>Aspergillus terreus</I>. The microsome bound AOx preparation was then immobilized into polyurethane foam matrix following a simple adsorption technique. The successful immobilization of the enzyme into the foam matrix was demonstrated microscopically and by biological staining. The enzyme loading was measured as ∼2.02Umg<SUP>−1</SUP> (76.6mgprotein %) of polyurethane foam. The optimum activity of the immobilized enzyme was detected in the pH range 7.0–8.0. The catalytic activity of the immobilized AOx was utilized for the production of <I>n</I>-heptanal. A maximum <I>n</I>-heptanal yield of 20.7±1.2% (w/w) was achieved at a substrate concentration of 10mM <I>n</I>-heptanol; beyond this concentration substrate dependent inhibition of the catalytic reaction was observed. The operational stability of the immobilized enzyme was determined and found to be ∼60% of the initial activity till the fifth reaction cycle, thus providing high cumulative yield of the product. The deactivation (<I>k</I><SUB><I>d</I></SUB>) and half-life time (<I>t</I><SUB>1/2</SUB>) of the immobilized enzyme were 5.17×10<SUP>−5</SUP>min<SUP>−1</SUP> and ∼9days, respectively. The results demonstrated the potential application of the polyurethane foam immobilized microsomal AOx-based environmentally benign biocatalytic process for the production of industrially important <I>n</I>-heptanal.</P>