Endogenous phthalates as a prospective regulator of interspecific relations in a biocoenosis

Abstract

It is widely believed that phthalates are xenobiotic pollutants whose prevalence in the environment is associated with their facilitated diffusion from plastic materials. Studies into the effect of synthetic phthalates on living organisms revealed their extremely negative action on the metabolism of animals and humans. The acting mechanism of these compounds is realised through a ligand-receptor pathway. Along with dioxins, polychlorinated biphenyls and similar compounds, phthalates are classified as endocrine disrupters. However, at present, sufficient evidence has been accumulated confirming the natural origin of phthalates. Thus, phthalates were de novo biosynthesised from labelled precursors in an algae culture. These compounds were detected in closed experimental systems, including cell cultures of highest plants, as well as those isolated from a number of bacterial, fungi, lowest and highest plant forms located far from the sources of technogenic pollution. The concept of phthalate biogenesis assumes the action of these compounds on living systems. Phthalates exhibit bactericidal and fungicidal action and compose allelopathic exudates, suppressing the growth of competing plant forms. Phthalates possess insecticidal and repellent properties. An analogy can be traced between the action of phthalates and endocrine disrupters of another chemical category, namely phytoestrogens, which regulate herbivorous mammal populations. A hypothesis is proposed about the biological role of endogenous plant phthalates representing secondary metabolic compounds. Exhibiting predominantly a shielding function, these compounds participate in the network of interactions between plants, animals, fungi and microorganisms. It should be noted that synthetic and endogenous phthalates are characterised by essential stereochemical differences, which can explain their different action on living organisms.