Recent advances in bioengineering and functional applications of microbial biocomposites: integrating bacterial cellulose, fungal mycelium and synthetic biology

The development of microbial biocomposites represents a promising frontier in the design of sustainable, multifunctional, and environmentally friendly materials. This minireview synthesises recent advances (2020-2026) in the production, modification, and application of biocomposites derived from microorganisms, with a focus on bacterial cellulose (BC) and fungal mycelium. It explores their synergies with emerging approaches in synthetic biology, 3D printing, and mineral functionalisation. Key microbial systems such as Komagataeibacter spp. and Ganoderma spp. are discussed, alongside structural and functional engineering strategies including in situ hydroxyapatite mineralisation, incorporation of plant fibres, and the addition of functional nanomaterials such as graphene oxide. The review further highlights the integration of these materials into high-value applications, including osteogenic scaffolds, self-healing living materials, biodegradable packaging, and environmental remediation systems. Finally, it addresses current regulatory and technical challenges related to industrial scalability, functional stability, and batch-to-batch standardisation. This article aims to provide a critical and comprehensive perspective for researchers and professionals in applied microbiology, materials science, and industrial biotechnology, emphasising the potential of microbial biocomposites as a convergent platform at the interface of sustainability, functional innovation, and bioinspired design.