Engineering Sustainable Bioplastics From Marine Polysaccharides: Extraction, Characterization, Performance Metrics, and Life Cycle Assessment

Bioplastics: A Sustainable Innovation for a Greener Future

Plastic pollution has become a global environmental crisis, threatening ecosystems, biodiversity, and human health. The extensive use of petroleum-based plastics, particularly single-use plastics, has resulted in the accumulation of persistent plastic waste in terrestrial and aquatic environments, contributing significantly to microplastic pollution and ecological degradation. Bioplastics have gained considerable attention as sustainable alternatives because they are derived wholly or partially from renewable resources and may exhibit biodegradable properties depending on their composition. Feedstocks such as corn starch, sugarcane, cellulose, algae, and microbial biomass offer environmentally friendly alternatives to fossil-based raw materials while supporting the transition toward a circular bioeconomy. This review provides a comprehensive overview of bioplastics, including their classification, raw materials, production techniques, industrial applications, environmental and economic benefits, current limitations, and recent technological advancements, highlighting their role in reducing plastic pollution and advancing sustainable materials science. With growing global interest in eco-friendly alternatives, bioplastics are expected to play a crucial role in reducing plastic waste, promoting green manufacturing, and shaping sustainable consumer behaviour. Continued research, technological innovation, supportive government policies, and improvements in waste management infrastructure will be essential to enhance the performance, affordability, and large-scale adoption of bioplastics in the future.

Microbial and Enzymatic Strategies for Plastic Waste Biodegradation: Mechanistic Pathways, Environmental Challenges, and Emerging Biotechnological Strategies

This review includes various bacterial and fungal enzymes associated with major stages of microbial plastic degradation, including biodeterioration, biofragmentation, bioassimilation, and mineralization and highlights recent advancements in metagenomics, enzyme engineering, synthetic biology, and multi‐omics approaches that helps in improving the efficiency and large‐scale industrial feasibility of microbial plastic degradation.

Waste-derived biopolymers as sustainable alternatives to conventional petroleum-based plastics: a multi-criteria review of feedstocks, performance and circularity

Advancing a Circular Bioeconomy through the Microbial Synthesis of Eco-Friendly Plastics from Marine Sources

: The increasing prevalence of plastic pollution demands strategies for sustainable biodegradable plastic production. Marine bacteria can be found on all continents able to survive in a variety of salinity levels and may be used to biosynthesis polyhydroxyalkanoates (PHAs), which can serve as a bioplastic substitute for conventional petroleum-based plastics. This paper presents a literature review and case study examining marine PHAs-producing microorganisms in the context of a circular bioeconomy and waste management. More specifically, it examines the marine PHA-producing bacteria’s ability to utilise varying and renewable carbon substrates for PHA biosynthesis. From prior research studies, it was found that diversity of marine bacteria possesses the ability to produce short-chain length (scl-PHA) and medium-chain length (mcl-PHA) types of PHAs, leading to wide potential applications. The integration of marine bacterial processes not only mitigates waste and pollution in the environment but also contributes to carbon cycling through the conversion of greenhouse gases into valuable biopolymers. This demonstrates the importance of marine microbes for bioplastic production and reinforces the need for the use of marine biota in the management of bioplastics to achieve a sustainable and circular economy.

Bioplastics for a Circular Economy: Feedstocks, Processing, Lifecycle Sustainability, and Pathways to Industrial Scale

The global plastic pollution crisis demands a fundamental re-evaluation of materials systems beyond incremental improvements to fossil fuel-based polymers. Bioplastics, polymers derived from renewable biological feedstocks, biodegradable under defined conditions, or both, offer a chemically diverse and rapidly evolving platform for transitioning toward circular materials economies in which the value of carbon, energy, and material is retained across multiple use cycles. This review provides a comprehensive and critically organized account of the bioplastics field, spanning three generations of feedstock development from food crops through lignocellulosic residues to algae and waste streams; primary production pathways including microbial fermentation, ring-opening polymerization, and biosynthesis; forming processes from extrusion and injection molding to additive manufacturing; and the mechanical, thermal, and barrier properties that determine application fitness. Particular emphasis is placed on life cycle assessment, which reveals that bioplastics’ climate benefits are conditional on feedstock choice, land-use management, energy source at manufacturing, and end-of-life pathway, and that burden-shifting from greenhouse gas emissions to land use, water consumption, and eutrophication is a systematic risk requiring integrated LCA evaluation rather than single-metric optimization. The review further examines end-of-life recycling, composting, and biodegradation pathways; market applications across packaging, agriculture, automotive, biomedical, and electronics sectors; and the growing role of artificial intelligence and machine learning in accelerating materials design, process optimization, and lifecycle data management. Critical barriers to scale, such as cost premiums of 20–75% over conventional plastics, inadequate composting infrastructure, recycling stream contamination, regulatory fragmentation, and consumer labeling confusion, are systematically analyzed alongside mitigation strategies. The review concludes with a forward-looking discussion of emerging feedstocks, smart and functional bioplastics, and the policy and infrastructure investments required to translate the environmental promise of bio-based polymers into realized circular economy impact.

Lignin, an Eco-friendly Biocomponent for a Sustainable Future

Lignin is the second most abundant terrestrial biopolymer and the largest natural reservoir of renewable aromatic carbon. Historically discarded or combusted as a low-value by-product of pulping and biorefining operations, lignin is increasingly recognised as a versatile feedstock capable of displacing petroleum-derived aromatics across materials, energy and environmental sectors. This review critically synthesises recent literature on lignin structure, extraction, valorisation and application, with particular attention to biomedical nanomaterials, food packaging, adhesives and polyurethane systems, carbon fibres, energy storage devices, water remediation, agriculture and biofuel production. The structural heterogeneity of lignin, arising from variable monolignol composition and interunit linkages, is examined as both the principal barrier to, and the source of functional richness underpinning, its valorisation. Extraction technologies, including kraft, sulfite, soda, organosolv and emerging ionic-liquid and deep-eutectic-solvent processes, are compared in terms of purity, yield, structural preservation and environmental burden. Applications are organised according to technology readiness and market relevance, and five summary tables consolidate quantitative findings on lignin sources, extraction performance, material applications, energy-related uses and environmental functions. The review further considers policy instruments and circular-bioeconomy frameworks that influence commercial uptake. Persistent obstacles, notably structural variability between feedstocks, incomplete standardisation of technical lignin grades and unresolved life-cycle trade-offs, are discussed alongside promising directions in catalytic depolymerisation and lignin-first biorefinery architectures. The evidence indicates that lignin valorisation is central to the transition towards a resource-efficient, low-carbon bioeconomy, provided that fractionation, standardisation and techno-economic barriers are addressed through coordinated research and policy action.