RT journal article
T1 Effect of ozone pre-treatment on polyhydroxyalkanoate production from  dark fermentation effluents
A1 Díaz-Domínguez, Encarnación
A1 Romero-Vargas, Agustín
A1 Fernández-Güelfo, Luís Alberto
A1 Fernández-Morales, Francisco Jesús
A1 Ibáñez-López, María Eugenia
A1 Lyng, James
A1 García-Morales, José Luis
A2 Tecnologías del Medio Ambiente
K1 Ozone pre-treatment
K1 Biosolids
K1 Vinasses
K1 Acidogenic fermentation
K1 Bioplastic precursor
K1 PHA
AB This study examines the biosynthesis of polyhydroxyalkanoates (PHAs) by a Cupriavidus necator pure culture using permeates obtained from the acidogenic dark fermentation of ozonized and non-ozonized organic wastes. The influence of ozone pre-treatment on permeate composition, and its subsequent impact on PHA production, was systematically assessed by analyzing PHA yield, volatile fatty acid (VFA) uptake, and microbial growth dynamics. From the results obtained, it was observed that ozonation significantly enriched the permeate, increasing dissolved organic carbon by 59.43% and dissolved nitrogen by 47.61%, resulting in a C/N ratio of 6.55—close to the optimal ratio (C/N = 6) for efficient PHA fermentation. Additionally, ozone pre-treatment shifted the VFA profile, increasing butyric acid concentration by 88%, a preferred substrate for C. necator during PHA biosynthesis. The ozone pre-treatment led to a 15% increase in microbial growth and a 60% improvement in PHA production, raising the final accumulation from 0.85 g/L to 1.35 g/L.Kinetic and stoichiometric modeling corroborated the advantageous role of ozonation, demonstrating a marked enhancement in carbon conversion efficiency, with PHA yields reaching 0.91 g PHA/g VFA and a maximum biomass-specific accumulation of 4 g PHA/g biomass, corresponding to an intracellular PHA content of 80%. These results underscore ozone pre-treatment as a powerful strategy for optimizing VFA-to-PHA bioconversion, revealing its capacity to offer a promising route toward more efficient and sustainable biorefinery processes.
PB Elsevier
SN 1385-8947
YR 2026
FD 2026-02-21
LK http://hdl.handle.net/10498/39298
UL http://hdl.handle.net/10498/39298
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 25-may-2026