Chemical profile, biological potential, bioprospection and biotechnological application of endophytes of Rumex: A systematic review

Abstract

Medicinal plants are widely used in the treatment of various ailments and are known to produce a wide range of secondary metabolites with potent pharmacological effects. These potent phytochemicals have been isolated from medicinal plants, including the genus Rumex prevalent worldwide. Various plants of the genus Rumex are reputed for producing anthraquinones in addition to flavonoids, acids, ketones, alcohol, naphthalene, terpenes, steroids, and stilbenoids, with potent pharmacological efficacies. They have been mostly investigated for anticancer, antimicrobial, anti-diabetic, antioxidant, and cholinesterase inhibitory activity. The interior tissue of medicinal plants is known to harbor microorganisms known as endophytes that are harmless to the host plant under normal conditions. They have been reported to protect the host plant against pathogenic microorganisms and insects, confer drought tolerance to the plant and promote plant growth. Endophytes have attracted the attention of researchers in recent years and different plant species, including Rumex have been selected for their isolation and characterization. Although, only a few numbers of plants of Rumex have been investigated for their endophytes. In this review, we compiled information on endophytes from various species of Rumex, exhibiting their bioactive compounds, pharmacological potential, and their application in biotechnology for the first time. The review revealed that the endophytic microflora of Rumex is much less explored as compared to the phytochemicals of their host plant and constitutes a potential starting point in the discovery of new endophytic species and novel bioactive secondary metabolites of endophytic origin. In addition, endophytic actinobacteria known to be a potential source of pharmacologically active secondary metabolites remain almost unexplored from Rumex. Hence, this paper is a starting point for further research on endophytic actinomycetes from Rumex species.