III International Conference

PP-I-28TUNING SURFACE MORPHOLOGY OF INORGANIC SUPPORTS FORADSORPTIVE IMMOBILIZATION OF ENZYMATIC ACTIVE SUBSTANCESKovalenko G.A., Perminova L.V., Chuenko T.V., Terentieva T.G., Rudina N.A.Boreskov Institute of Catalysis SB RAS, Novosibirsk, RussiaE-mail: galina@catalysis.nsk.suComparative study of inorganic supports with different morphology of carbon surfacelayer was carried out for adsorptive immobilization of both enzymes (glucoamylase), yeastmembrane (with invertase activity) and non-growing bacteria Arthrobacter nicotianae (withglucose isomerase activity) to develop heterogeneous biocatalysts for the biotech processesfor sweeteners production (starch treacle, syrups). As a result of tuning morphology towardimmobilizing enzymatic active substances, the catalytic filamentous carbon (CFC) was foundto ensure the highest stability and activity of the biocatalysts prepared due to mesoporousstructure, roughness and optimal hydrophilic-hydrophobic balance of the CFC-layer.The highly stable biocatalysts based on immobilized enzymatic active substances are at theheart of the modern biotech processes performed in continuous heterogeneous mode that isundoubtedly attractive and feasible for implantation in large-scale industry. The comprehensiveresearch of the different inorganic support distinguished by macrostructure (honeycombmonoliths, foams, granules) and morphology of carbon layer (filamentous, graphite-like,pyrolytic carbons) were carried out to study of peculiarities of adsorptive immobilizations ofenzymatic active substances. The purposeful tuning the surface morphology was carried out toprovide the enhancement of stability and activity of the biocatalysts prepared for the productionof starch treacle, invert sugar and glucose-fructose syrups.The biocatalytic properties (activity and stability) of immobilized enzymatic activesubstances were found to depend strongly on the morphology of carbon layer on the surface.In particular, catalytic filamentous carbon layerwas synthesized during hydrogen-propanebutanepyrolysis on the deposited Ni-catalyst.For foamed glass, CFC-layer was found toprovide the highest long-term and operationalstability of immobilized glucoamylase incomparison with graphite-like layer (fig. 1).The biocatalyst retained 50% of initial activityafter 1 year-storage at ambient temperature(fig. 1, curve 2). The half-life time of the biocatalystwas more than several hundred hours ofcontinuous dextrin hydrolysis at 50±5 o C [1].58