The present invention concerns a natural biocomposite powder prepared from the biomass of yeast Pichia pastoris, comprising chitin-glucan complex (CGC) and mannose-containing polysaccharides. In a second aspect, the invention concerns the method of preparation of the natural biocomposite powder. The invention also concerns the method to obtain Pichia pastoris biomass with increased CGC content, as well as increased chitin to glucan content in the CGC. Finally, the invention concerns the use of the natural biocomposite powder, prepared from the cell wall of yeast Pichia pastoris by the method according to the invention, as excipient in the pharmaceutical, cosmetics or food industries.