Ethanol production from macaúba (Acrocomia aculeata) presscake hemicellulosic hydrolysate by Candida boidinii UFMG14

Yeasts capable of growth on xylose were isolated from macaúba (Acrocomia aculeata) fruit, a Brazilian palm tree with great potential for use as biodiesel feedstock production. Candida boidinii UFMG14 strain achieved the highest ethanol production (5 g/L) and was chosen to ferment macaúba presscake hemicellulosic hydrolysate (MPHH). The MPHH was produced by the first time in this work and the resultant fivefold concentrate showed considerable sugar content (52.3 and 34.2 g/L xylose and glucose, respectively) and low furfural (0.01 g/L) and hydroxymethylfurfural (0.15 g/L) concentrations. C. boidinii UFMG14 fermentation was evaluated in supplemented and non-supplemented MPHH containing either 10 or 25 g/L of xylose. The maximum ethanol production (12 g/L) was observed after 48 h of fermentation. The ethanol yield was significantly affected by supplementation and concentration of MPHH while ethanol productivity was affected only by MPHH concentration. This is the first study demonstrating theC. boidinii potential for ethanol production from hemicellulose byproducts.