USE OF LOW QUALITY BARLEY STARCH FOR THE PRODUCTION OF AMYLOLYTIC ENZYMES BY Aureobasidium pullulans

Low quality barley that has been rejected for the malt production process can be used to produce value added products, particularly enzymes. Hence, in this work the starch was extracted and used to produce amylolytic enzymes by Aureobasidium pullulans. Using 50 g/L of barley raw starch, glucoamylase...

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Detalles Bibliográficos
Autores: Hernández-Castillo, María Isabel, Hernández-Navarrete, Angélica, Jiménez-Montejo, Fabiola Eloisa, Cruz-López, María del Carmen, Hidalgo-Lara, María Eugenia, López y López, Víctor Eric
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2019
País:México
Institución:UNIVERSIDAD NACIONAL AUTÓNOMA DE MÉXICO
Repositorio:Revista Internacional de Contaminación Ambiental
Idioma:español
OAI Identifier:oai:ojs.pkp.sfu.ca:article/52973
Acceso en línea:https://www.revistascca.unam.mx/rica/index.php/rica/article/view/RICA.2019.35.02.14
Access Level:acceso abierto
Palabra clave:sacarificación
glucoamilasa
α-amilasa
α-glucosidasa
β-glucosidasa
saccharification
α-amylase
glucoamylase
α-glucosidase
β-glucosidase
Descripción
Sumario:Low quality barley that has been rejected for the malt production process can be used to produce value added products, particularly enzymes. Hence, in this work the starch was extracted and used to produce amylolytic enzymes by Aureobasidium pullulans. Using 50 g/L of barley raw starch, glucoamylase, α-amylase, α glucosidase and β-glucosidase enzymes were produced with maximum activities of 193, 7.4, 8.1 and 8.5 U/mL, respectively. After 30 h of fermentation a crude extract was obtained, which was used as enzymatic source for the saccharification of starch from three sources at 10 g/L: barley, soluble (from potato) and corn. First, two reaction solvents (water and acetate buffer) and the addition of calcium (Ca2+) were evaluated. Afterwards, starch gelatinization was evaluated and finally experiments varying the starch concentration (from 50 to 400 g/L) were conducted. Using water as solvent and the Ca2+ addition had a positive effect, resulting in a maximum glucose concentration of 3.84, 0.84 and 0.4 g/L from barley, soluble and corn starches, respectively. In the other hand, starch gelatinization was positive for soluble and corn starches, enhancing hydrolysis in 23 and 25 %, respectively. Increasing the starch concentration to 50 g/L was the best condition, enhancing hydrolysis in 3.2, 40 and 42 % from barley, soluble and corn starches, respectively. This work demonstrates that low quality raw barley starch can be used for the production of value added products such as enzymes.