Targeted Acidogenic Fermentation of Waste Streams for the Selective Production of Volatile Fatty Acids as Bioplastic Precursors

The sustainable production of bioplastics is increasingly important for reducing reliance on fossil fuels and addressing environmental challenges. The acidogenic fermentation of waste streams offers a promising pathway for generating key bioplastic precursors, such as volatile fatty acids, which can be used to produce polymers like polyhydroxyalkanoates. This review explores the potential of various waste streams, including agricultural residues, industrial by-products, and food waste, as substrates for acidogenic fermentation, aligning with circular economy principles by reducing waste and environmental impact. A key feature of this review is its focus on targeted acidogenic fermentation, which optimizes process conditions to maximize the production of specific acids based on waste characteristics. The analysis emphasizes how the chemical composition and biodegradability of waste streams influence the selection of microbial consortia and metabolic pathways, determining the yield and composition of the products generated. The review also highlights the adaptability of acidogenic fermentation to heterogeneous and variable waste streams, underlining its potential as a scalable and sustainable solution for bioplastic precursor production. By tailoring process parameters such as pH and hydraulic retention time to the specific characteristics of the substrate, targeted acidogenic fermentation can effectively transform waste into high-value intermediates. Finally, challenges related to the scalability and economic feasibility of these processes are discussed, along with opportunities for integrating acidogenic fermentation with complementary waste valorization technologies to advance the bio-based economy. The findings underscore the critical role of waste streams in enabling the sustainable and efficient generation of bioplastic precursors, contributing to a circular economy framework.