Hydrolysis of soybean isoflavones by Debaryomyces hansenii UFV-1 immobilised cells and free β-glucosidase

• Autor(a) principal: Maitan-Alfenas, Gabriela P.
• Data de Publicação: 2014
• Outros Autores: Lage, Lorena G. de A., Almeida, Maíra N. de, Visser, Evan M., Rezende, Sebastião T. de, Guimarães, Valéria M.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: https://doi.org/10.1016/j.foodchem.2013.09.099; http://www.locus.ufv.br/handle/123456789/12419
• topic: Debaryomyces hansenii UFV-1; β-Glucosidase; Immobilisation; Isoflavones; Soy molasses

An intracellular β-glucosidase from Debaryomyces hansenii UFV-1 was produced in an YP medium with cellobiose as the carbon source. This enzyme was purified, characterised and presented a Mr of 65.15 kDa. Yeast cells containing the intracellular β-glucosidase were immobilised in calcium alginate. The free β-glucosidase and immobilised cells containing the enzyme presented optima values of pH and temperature of 6.0 and 45 °C and 5.5 and 50 °C, respectively. The free enzyme maintained 62% and 47% of its original activity after 90 days at 4 °C and after 15 days at room temperature, respectively. The immobilisation process resulted in higher enzyme thermostability at 45 and 50 °C. Soy molasses treatment with the free enzyme and the immobilised cells containing β-glucosidase, for 2 h at 40 °C, promoted efficient hydrolysis of isoflavone glicosides to their aglycon forms. The results suggest that this enzyme could be used in the food industry, in the free or immobilised forms, for a safe and efficient process to hydrolyse isoflavone glycosides in soy molasses.