Biocomposites and related fabrication methods and systems are described, the biocomposites comprising compacted plants and/or algae cells having a water content of less than 15 wt %, and a minimized pore presence and/or dimensions, in which the compacted cells are in a lamellar stacked configuration with a plurality of lamellae arranged one above the other, each lamella independently having a thickness of 20 nm to 5 μm and comprising a semi-crystalline structure formed by biopolymers of cell walls of the compacted plant and/or algae cells.