Evolving biocatalysis to meet bioeconomy challenges and opportunities

4siThe unique selectivity of enzymes, along with their remarkable catalytic activity, constitute powerful tools for transforming renewable feedstock and also for adding value to an array of building blocks and monomers produced by the emerging bio-based chemistry sector. Although some relevant biotransformations run at the ton scale demonstrate the success of biocatalysis in industry, there is still a huge untapped potential of catalytic activities available for targeted valorization of new raw materials, such as waste streams and CO2. For decades, the needs of the pharmaceutical and fine chemistry sectors have driven scientific research in the field of biocatalysis. Nowadays, such consolidated advances have the potential to translate into effective innovation for the benefit of bio-based chemistry. However, the new scenario of bioeconomy requires a stringent integration between scientific advances and economics, and environmental as well as technological constraints. Computational methods and tools for effective big-data analysis are expected to boost the use of enzymes for the transformation of a new array of renewable feedstock and, ultimately, to enlarge the scope of biocatalysis.partially_openopenPellis, Alessandro; Cantone, Sara; Ebert, Cynthia; Gardossi, LuciaPellis, Alessandro; Cantone, Sara; Ebert, Cynthia; Gardossi, Luci

Chemo-Enzymatic Epoxidation of Unsaturated Fatty Acids

Epoxy fatty acids are useful molecules and find a number of applications e.g. as PVC plasticisers and stabilisers, additives in polyurethane production, reactive diluents in paints, corrosion protection agents, etc. Chemo-enzymatic epoxidation of unsaturated fatty acids has been studied; the peracid formation was catalysed by immobilised Candida antarctica lipase B (Novozym 435), and hydrogen peroxide was used as oxygen donor. A method based on HPLC for the analysis and quantification of unsaturated fatty acids and their epoxides was developed. The process of chemo-enzymatic epoxidation was optimised with an aim to minimise solvent use and maximise productivity. Epoxystearic acid and epoxystearic acid methyl ester were synthesised in very good yields in solvent free conditions, and is suggested to be a good alternative to the traditional epoxidation methods for epoxidation of fatty acids and oils. Subsequently, the effect of the reaction parameters on the epoxidation of linoleic acid was investigated. Hydrogen peroxide was found to have a significant effect on the reaction rate and degree of epoxidation. The same enzyme was then used to synthesise alkyl esters of epoxystearic acid, the esterification and perhydrolysis reactions being catalysed by the lipase in one pot. Butyl epoxystearate was synthesised with high yields. The parameters affecting lipase activity and operational lifetime during the chemo-enzymatic epoxidation were investigated. The high concentration of hydrogen peroxide used for the reaction inactivates the enzyme at high temperature, hence limiting recycling of the biocatalyst. Results suggest that temperature control and careful dosage of hydrogen peroxide are among the most important parameters for industrial chemo-enzymatic epoxidation

Environmentally evaluated HPLC-ELSD method to monitor enzymatic synthesis of a non-ionic surfactant.

N-Lauroyl-N-methylglucamide is a biodegradable surfactant derived from renewable resources. In an earlier study, we presented an enzymatic solvent-free method for synthesis of this compound. In the present report, the HPLC method developed to follow the reaction between lauric acid/methyl laurate and N-methyl glucamine (MEG) and its environmental assessment are described

Stability of immobilized Candida antarctica lipase B during chemo-enzymatic epoxidation of fatty acids

The parameters affecting the lipase activity and operational lifetime during chemo-enzymatic epoxidation of fatty acids were investigated. Immobilized Candida antarctica lipase B (Novozym (R) 435) was incubated in the presence of various reaction components (i.e. toluene, water, H2O2, oleic acid, perpalmitic acid, and epoxystearic acid, respectively) at temperatures between 20 and 60 degrees C followed by measurement of residual enzyme activity. Epoxystearic acid was shown to slightly inactivate the enzyme at 50 degrees C, while oleic acid and perpalmitic acid did not. No deactivation of the enzyme was observed in presence of toluene/water mixture within 48 h at 20-60 degrees C. In the presence of 6-12 M hydrogen peroxide, the enzyme was rather stable at 20 degrees C, while at 60 degrees C the enzyme lost activity rapidly, with the rate of deactivation increasing with increasing hydrogen peroxide concentration. These results imply that temperature control and careful dosage of hydrogen peroxide would be essential in an industrial chemo-enzymatic process. (c) 2006 Elsevier Inc. All rights reserved

Chemo-enzymatic epoxidation of oleic acid and methyl oleate in solvent-free medium

Chemo-enzymatic epoxidation of oleic acid (OA) and its methyl ester has been performed using hydrogen peroxide and immobilized lipase from Candida antarctica (Novozym(R) 435). The purpose of the study was to characterize the reaction under solvent-free conditions. The reaction temperature had a significant impact on epoxidation of OA. At lower temperatures, the substrate conversion was hindered by the formation of solid epoxystearic acid product. Nearly 90% conversion of OA to the epoxide product was obtained after 6 h at 50 degrees C. Longer reaction times at 40 degrees C and above resulted in by-product formation and eventually lowered the product yield. In contrast, the reaction with methyl oleate (MO) was less influenced by temperature. Almost complete epoxidation was achieved at 40-60 degrees C, the higher the temperature the shorter was the reaction time. The main epoxidation product obtained was epoxystearic acid methyl ester (EME), and the remaining was epoxystearic acid (EA) formed by the hydrolytic action of the lipase. Recycling of the lipase for epoxidation of MO at 50 degrees C indicated that the immobilized enzyme was prone to activity loss

Lipase mediated simultaneous esterification and epoxidation of oleic acid for the production of alkylepoxystearates

Epoxy alkylstearates were synthesized by lipase catalysed esterification and perhydrolysis followed by epoxidation of oleic acid in a one-pot process. Immobilized Candida antarctica lipase (Novozym 435) was used as the catalyst. The esterification reaction occurred relatively quickly and was followed by epoxidation of the alkyl ester and the remaining fatty acid. Higher degree of esterification was achieved with n-octanol, n-hexanol and n-butanol as compared to that with ethanol and iso-propanol. The rate and yield of epoxidation was enhanced with iso-propanol but was lowered with the other alcohols. The lipase suffered significant loss in activity during the reaction primarily due to hydrogen peroxide. The presence of alcohols, in particular ethanol. further contributed to the enzyme inactivation. The epoxidation reaction could be improved by step-wise addition of the lipase. (c) 2006 Elsevier B.V All rights reserved