RT info:eu-repo/semantics/masterThesis
T1 Valoración de un consorcio de microalgas y bacterias: comparación de métodos convencionales y nuevos métodos de extracción asistida
A1 Filipigh, Ángel Alejandro
A2 Universidad de Valladolid. Facultad de Ciencias
K1 Microalgas
K1 Ultrasonidos
K1 Microondas
AB The microalgae biomass grown in wastewater becomes an interesting renewable raw material able to metabolize the nutrients of waste streams and transform them into high added products such as proteins and carbohydrates. Despite the actual interest in the use of this biomass to improve de viability of conventional wastewater treatment processes, the research carried out on the fractional valorization of these macrocompounds is still very scarce. In the present work, a comparison of several conventional methodologies is developed (chemical hydrolysis, enzymatic hydrolysis and pretreatments coupled with enzymatic hydrolysis) against novel methodologies of enzymatic hydrolysis assisted by ultrasound and microwaves for the solubilization and recovery of macrocompounds, such as proteins and carbohydrates, from a consortium of Scenedesmus almeriensis-bacteria cultivated in a thin-film photobioreactor fed with manure wastewater.The acid hydrolysis with HCl 2M at 120ºC enhanced the carbohydrates solubility (86,6%) with high fermentable monosaccharide recoveries (60.7%). The alkaline hydrolysis with NaOH 2M at 120ºC achieved almost complete solubilization of the biomass components with high solubilization (88.3%) and recovery yields (61.5%) of proteins with peptide size less than 11 kDa, but with high carbohydrates losses. The enzymatic hydrolysis with proteases gave raise to moderate carbohydrates recoveries (14.9%) and peptides (17.6%), while the addition of cellulases to the enzymatic cocktail achieved an improvement in the yields of proteins, although, in both cases, the sizes of the recovered peptides were found in the range of 20-135 kDa. The secuencial application of pretreatments (bead mills or ultrasound) coupled with enzymatic hydrolysis with proteases improved the solubilization of carbohydrates (35%) and proteins (28.2%) of the biomass but, the recovery yields obtained were within the range obtained only with enzymatic hydrolysis with proteases in a single stage (15% and 24%).Finally, regarding the novel enzymatic hydrolysis methods with proteases and the cocktail of proteases and cellulases, the use of microwaves enhanced the release of carbohydrates with a maximum yield of 57.9% and 56.2% respectively, while ultrasounds enhanced the release of proteins up to 49.6% and 44.5% with recovered peptides sizes greater than 48 kDa. In both cases, the yields were much higher than those of the individual enzymatic hydrolysis using a single stage, despite the fact that it was operated with treatment times of only 1h. The presence of bacteria in this biomass could be related to the high losses obtained.
YR 2021
FD 2021
LK https://uvadoc.uva.es/handle/10324/49743
UL https://uvadoc.uva.es/handle/10324/49743
LA spa
NO Departamento de Ingeniería Química y Tecnología del Medio Ambiente
DS UVaDOC
RD 17-jul-2024