Abstract: A process for producing biologically active factors from a substrate, in the form of cell homogenates of organ tissues, of microorganisms, plant components and/or body fluids. To this end, the substrate, in an aqueous form and freed of accompanying particulate substances, is selectively separated by affinity chromatography using a biological sorbent, in the case of which at least one nucleic acid (desoxyribonucleic and/or ribonucleic acid) or at least one protein or peptide is coupled to a carrier substance; in the primary eluate components having no affinity are present, while the active factors (which have an affinity) are secondarily eluated. By binding nucleic acids or proteins from a given origin to a carrier, active factors with special properties such as tumor inhibiting substances, or stimulating substances may be positively produced.