Toward the coupling of microbial biosynthesis and catalysis for the production of alkylated phenolic compounds

Abstract

In the present study, petroleum-free production of alkylated phenols from glycerol was achieved by judicious use of microbial biosynthesis and heterogeneous catalysis with the aim to advance biomass conversion to industrially relevant chemical products. First, metabolically engineered bacterium Escherichia coli was adopted to convert glycerol to phenol. Biophenol was then extracted from the cell culture using select polymeric resins. Desorption of phenol was achieved with tertiary butyl alcohol, which serves also as a reactant in subsequent heterogeneous catalytic reaction. The adopted resins were also compared as catalysts for alkylation of phenol to tert-butyl phenolic products. Interestingly, the resins exhibited different phenol adsorption and catalytic reactivities. The holistic approach developed by this study offers a unique opportunity to synthesize end products directly from glycerol that cannot be achieved in such an efficient manner (i.e., low temperature, low pressure, and high selectivity) by using microbial biosynthesis or heterogeneous catalysis approaches alone.