Kinetics study of invertase covalently linked to a new functional nanogel

High sucrolytic activity by invertase immobilized onto magnetic diatomaceous earth nanoparticles

“…We conclude that thermal stability of the mDE-APTES-invertase was better than the free invertase probably due to the covalent bond formation that might reduce the conformational flexibility of the enzyme and make it more stable against temperature changes [28]. Other authors also observed that after immobilization there was an improvement in thermal stability of enzyme [29], [30], [31].

Fig. 4(a) Thermal stability of free (clear bar) and immobilized (dot-filled bar) invertase at different temperatures and times.

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“…The decrease of the activity by the mDE-APTES-invertase may be attributed to loss of magnetic nanoparticles during the washing process between each cycle. Raj et al [31] reported the appreciable reusability of the immobilized invertase on nanogel-matrix up to eight cycles, but the relative activity decreased to 11.03% after the 9 th cycle. The reuse in long term for the mDE-APTES-invertase was assessed up to 120 days.…”

Synthesis of crosslinked lipase aggregates and their use in the synthesis of aspirin

“…However, the latter may involve the enzyme active sites in the covalent linkage resulting in the loss of enzyme activity (Villeneuve et al, 2000). Furthermore, this technique requires specially designed carriers or supports (Chauhan et al, 2007;Raj et al, 2011 chemical engineering research and design x x x ( 2 0 1 4 ) xxx-xxx the form of support. The catalytic activity of enzyme is diluted as the non-catalytic mass, support, constitutes the major part of the total mass (Roessl et al, 2010).…”

Bio-waste derived dialdehyde cellulose ethers as supports for α-chymotrypsin immobilization

“…The activity studies of the free and immobilized CT were carried out by variation of different parameters such as temperature (25 ºC-45 ºC), pH (2)(3)(4)(5)(6)(7)(8)(9)(10)(11), and BTEE concentration (0.5-2.5 mM). % Relative activity (%RA) was calculated by assigning the value of the highest SA in each set as 100% activity.…”

“…Many techniques have been used for immobilization of enzymes such as adsorption, ionic binding, covalent binding, cross-linking, entrapment and microencapsulation [3]. The covalent immobilization of enzymes on insoluble supports is one of the most extensively used methods of enzyme immobilization [4][5][6]. Covalent immobilization, through the covalent link of enzyme molecule to the activated groups of the support leads to enzyme stabilization.…”