Abstract

LOEZA-CORTE, J. M. et al. L-arabinose production by hidrolysis of mesquite gum by a crude extract with α-L-arabinofuranosidase activity from Aspergillus niger. Rev. Mex. Ing. Quím [online]. 2007, vol.6, n.3, pp.259-265. ISSN 1665-2738.

A crude enzymatic extract from Aspergillus niger 10 with α-L-arabinofuranosidase activity (EC 3.2.1.55) was obtained and its effect on the hydrolysis of mesquite gum was determined and compared to that of a commercial α-L-arabinofuranosidase from A. niger. The growth parameters of A. niger 10 obtained were X_max = 3.03 g L^-1 and μ_max = 0.07 h^-1. The maximum enzymatic activity obtained was 65.93 U L^-1. Optimum temperature and activation energy for the crude extract were 50°C and 46.15 KJ mol^-1 and for the commercial enzyme 40 °C and 52.76 KJ mol^-1, respectively. The apparent kinetic parameters K_m and V_max for the crude extract were 4.87 g L^-1 and 0.15 μmol min^-1 g^-1, and for the commercial enzyme 76.45 g L^-1 and 3.85 /mol min^-1 g^-1, respectively. Yields of L-arabinose recovery for the crude extract and the commercial enzyme were 17.04 % and 2.78 %, respectively, based on the reported average content of L-arabinose in mesquite gum.

Keywords : α-L-arabinofuranosidase; Aspergillus niger; mesquite gum; L-arabinose; enzymatic hydrolysis.