<b>Optimized acid hydrolysis of the polysaccharides from the seaweed <i>Solieria filiformis</i> (Kützing) P.W. Gabrielson for bioethanol production

• Main Authors: George Meredite Cunha de Castro, Norma Maria Barros Benevides, Maulori Curié Cabral, Rafael de Souza Miranda, Enéas Gomes Filho, Maria Valderez Ponte Rocha, Marjory Lima Holanda Araújo
• Format: Article
• Language: English
• Published: Universidade Estadual de Maringá 2017-11-01
• Series: Acta Scientiarum : Biological Sciences
• Subjects: iota-carrageenan; cellulose; galactose; kinetic parameters; fermentation; acclimation; sulfuric acid.
• Online Access: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/37227

The seaweeds are bio-resource rich in sulfated and neutral polysaccharides. The tropical seaweed species used in this study (Solieria filiformis), after dried, shows 65.8% (w/w) carbohydrate, 9.6% (w/w) protein, 1.7% (w/w) lipid, 7.0% (w/w) moisture and 15.9% (w/w) ash. The dried seaweed was easily hydrolyzed under mild conditions (0.5 M sulfuric acid, 20 min.), generating fermentable monosaccharides with a maximum hydrolysis efficiency of 63.21%. Galactose and glucose present in the hydrolyzed were simultaneously fermented by Saccharomyces cerevisiae when the yeast was acclimated to galactose and cultivated in broth containing only galactose. The kinetic parameters of the fermentation of the seaweed hydrolyzed were Y(P⁄S) = 0.48 ± 0.02 g.g−1, PP = 0.27 ± 0.04 g.L−1.h−1, h = 94.1%, representing a 41% increase in bioethanol productivity. Therefore, S. filiformis was a promising renewable resource of polysaccharides easily hydrolyzed, generating a broth rich in fermentable monosaccharides for ethanol production.