Transforming pretreated spent coffee grounds into polyhydroxyalkanoate bioplastic through fermentation processes

Identifier:  TFG:8007

Handle: https://hdl.handle.net/20.500.11797/TFG8007

Authors:  García Sánchez, Lídia

Abstract:
Lignocellulosic biomass is a sustainable feedstock for polyhydroxyalkanoate (PHA) production but requires harsh pretreatment, leading to inhibitors that hinder microbial growth. This study evaluates oxalic acid pretreatment on spent coffee grounds (SCG) to enhance fermentable sugars. After hydrolysis, SCG was fermented using Burkholderia sacchari IPT 101. The mild oxalic acid pretreatment reduced inhibitor formation, yielding 23.53 g/L of total sugars. Subsequent bacterial fermentation resulted in a polyhydroxybutyrate (PHB) concentration of 1.187 g/L with a PHB content of 55.37%. The findings highlight oxalic acid pretreatment as an effective method for improving biomass conversion and PHB production from SCG.