The invention relates to a polymer composition formed from a biologically degradable polymer and a material from sea plants and/or shells of sea animals or at least two components selected from the group consisting of saccharides and the derivatives thereof, proteins, amino acids, vitamins and metal ions. The invention additionally relates to a molded article formed from the polymer composition. The molded article may be packaging material or fibrous material, in the form of fibrous material as a mixing component for the production of yarns, and in the form of fibrous material for the production of nonwoven fabrics or woven fabrics.