Highly Active Nanobiocatalyst from Lipase Noncovalently Immobilized on Multiwalled Carbon Nanotubes for Baeyer–Villiger Synthesis of Lactones

A new method for the chemo-enzymatic Baeyer–Villiger oxidation of cyclic ketones to lactones in the presence of a new heterogeneous nanobiocatalyst consisting of Candida antarctica lipase B immobilized on multiwalled carbon nanotubes (MWCNTs) has been developed. To ensure safety and meet the contemporary environmental criteria nanobiocatalyst was used for the in situ generation of peracid, thereby avoiding the direct handling of dangerous peroxy substance. The reaction was carried out under mild conditions at 20–40 °C using 30% aq H₂O₂ as the primary oxidant, with octanoic acid as the precursor of peracid. The influence of the reaction parameters and various carbon materials as supports were studied. The activities of the new biocatalysts were compared with the benchmark Novozyme-435. Recycling studies demonstrated the possibility of utilizing the most active MWCNTs-lipase biocatalyst five times without any significant loss of activity. The main advantage of this study is the superior activity of the new nanobiocatalyst, what caused a significant reduction of reaction times compared to those previously reported in the literature