2026-04-20T16:30:21Zhttps://riubu.ubu.es/oai/request

oai:riubu.ubu.es:10259/62822022-12-02T13:08:56Zcom_10259_4244com_10259_5086com_10259_2604col_10259_4245

00925njm 22002777a 4500 dc Trigueros Andrés, Ester author Alonso Riaño, Patricia author Ramos Rodríguez, Cipriano author Diop, Cherif Ibrahima Khalil author Beltrán Calvo, Sagrario author Sanz Díez, Mª Teresa author 2021-12 The valorization of the underexploited solid residue after agar extraction from red marine algae was studied by subcritical water treatment. Experiments were carried out in two different semi-continuous fix-bed reactor configurations at 185 ºC at different subcritical water residence times. The use of a by-pass section allowed to heat the water previous contact to the biomass, avoiding the exposure of the sample to high temperatures during the heating procedure and reducing the formation of degradation products. Higher hydrolysis yields were obtained for the protein fraction (reaching 96.1%) than for the carbohydrate fraction (reaching 45.7%, 11.3%, 27.5% and 57.6% for galactans, glucans, arabinans and uronic acids, respectively). With the decrease of the residence time, by increasing the flow rate, higher initial hydrolysis rates were obtained due to enhancing diffusion of the hydrolysis products into the bulk solution. It was determined a similar dependence of the initial hydrolysis rates on the residence time for the carbohydrate oligomers and total protein fraction, but the release of free amino acids was less dependent on increasing flow rate due to higher diffusion coefficients for small molecules. 2213-3437 http://hdl.handle.net/10259/6282 10.1016/j.jece.2021.106768 Subcritical water hydrolysis (subW) Heating Residence time Biorefinery Macroalgae by-products Bio compounds Kinetic study of the semi-continuous extraction/hydrolysis of the protein and polysaccharide fraction of the industrial solid residue from red macroalgae by subcritical water