ABSTRACT
Humic substances are polyphenolic compounds. They have antiviral as well as desmutagenic effects and react with biopolymers such as collagen; thereby they have no toxic side effects by oral administration. In vitro incubation with humic substances raises the breaking point of the tail tendon of the rat by about 75%. The chemical resistance of the collagen fibres in tail tendon collagen is also increased by in vitro incubation with humic substances, at least insofar as the ultrastructurally and biophysically measurable destruction of the collagen fibres by 4 M guanidinium chloride is inhibited. As humic substances increase the mechanical and chemical resistance of collagen fibres and promote their "maturity", it seems likely that this effect of humic substances depends upon their interaction with the hydrogen bonding and covalent bonding of the collagen fibres. Such a conclusion is confirmed by the results of X-ray diffraction analysis.
