Woody biomass is an attractive source of renewable energy, chemicals and materials. Woody biomass is a complex material that is composed of multiple sugar carbohydrates besides nearly 40% of other chemicals. The mixed sugars can be converted to a range of chemicals, energy and materials humans need. For example, lactic acid (LA), 3-hydroxybutyric acid, and PHA can be fermented from the mixed sugar. PHA is a biodegradable and biocompatible polymer that has many applications, including agricultural and biomedical applications. Extracellular production of the hydroxyl acids is advantageous as compared with direct fermentation to PHA, in that the conversion efficiency is improved and the product properties can be tailored for different needs via controlling the polymerization of the 3-hydroxybutyric acids. The whole process renders the biodegradable and biocompatible polymer to be recyclable.