Endo-1,4-fucoidanase from Vietnamese marine mollusk Lambis sp. which producing sulphated fucooligosaccharides

The fucoidanase was isolated and purified from the digestive glands of the marine mollusk Lambis sp. The molecular mass of homogeneous enzyme as estimated by SDS electrophoresis was about 50 kDa. Optima of pH and temperature were at 4.9 and 37 °C, respectively. Its half-inactivation time was 20 min at 54 °C. The fucoidanase had a Km value of 1.3 mg ml−1 for the hydrolysis of fucoidan from Fucus evanescens. coidanase catalysed the hydrolysis of 1→3;1→4-α-l-fucans from Fucus evanescens and Fucus vesiculosus, but not 1→3-α-l-fucan from Saccharina cichorioides. Native fucoidan from F. evanescens was hydrolysed weakly in contrast to desulphated fucoidan. Based on the analysis of substrate specificity and the structure of the reaction products the fucoidanase from Lambis sp. catalyzed hydrolysis of 1→4-bonds in a fucoidan molecule as endo-enzyme.