Noble metal catalysts have been recently studied for optimum oxidation efficiency and selectivity; 87-89 Shi et al. reported less expensive Pt-Cu catalyst with 92% yield and 60% selectivity. Muconic acid, on the other hand, can be either biosynthesized from glucose or prepared from lignin through depolymerization and fermentation. The latter method is promising in that abundant lignocellulosic biomass waste can be used without depleting food supplies; however, feasibility analyses performed by Unlu et al. suggested that the lignin pathway is overall less sustainable and economical than the glucose-glutaric acid route.