# Use of Lipid Extract of Oat Flour as a Peroxygenase-Containing Biocatalyst Active in Organic Solvents

## TL;DR

Researchers found that oat flour's lipid extract contains active peroxygenase, a useful enzyme for chemical reactions in organic solvents.

## Contribution

A simple method to extract active peroxygenase from oat flour's lipid fraction, usable in organic solvents.

## Key findings

- Lipid fraction of oat seeds retains peroxygenase activity without complex purification.
- LF-peroxygenase shows higher activity and stability in organic solvents compared to microsome preparations.
- Successful preparative-scale oxidation of thioanisole with high stereoselectivity and yield.

## Abstract

Oat seeds contain peroxygenase, a heme enzyme localized in both the microsomal and the lipid droplet fractions, which are usually separated by multiple ultracentrifugation steps. In this work, it was shown that peroxygenase activity is retained in the lipid fraction (LF) of oat seeds, which is obtained by simple extraction of flour with organic solvents. The enzymatic activity of this crude preparation was tested in the oxidation of thioanisole in comparison with a peroxygenase-containing microsome preparation (MP) from the same plant source in both aqueous medium and pure organic solvents. In most cases, higher activity was observed in the LF preparation, which proved to be stable in organic solvents for at least 24 h, thus offering a good option for the oxidation of highly water-insoluble substrates. LF-peroxygenase maintained the same stereoselectivity features observed with MP, as also demonstrated in the epoxidation reaction of limonene. A protocol for the oxidation of thioanisole in CH3CN was set up on a preparative scale, and the corresponding sulfoxide was obtained at concentration of 1.7 M and with 84% ee.