Synanthropic Plants as an Underestimated Source of Bioactive Phytochemicals: A Case of Galeopsis bifida (Lamiaceae)

Daniil N Olennikov

doi:10.3390/plants9111555

Abstract

Hemp nettle (Galeopsis bifida Boenn.) is a synanthropic species of the Lamiaceae family that is widely distributed across Europe, Asia, and Siberia. Galeopsis bifida is deeply embedded in the ethnomedical tradition of Asian healers; however, this plant is still poorly characterized, both chemically and pharmacologically. To study Siberian populations of G. bifida, we used high-performance liquid chromatography with photodiode array and electrospray triple quadrupole mass detection for metabolic profiling. Ninety compounds were identified, including iridoid glycosides, phenylethanoid glycosides, hydroxycinnamates, and flavone glycosides, most of which were identified in G. bifida for the first time, while some phenolics were found to have potential chemotaxonomic significance in the Lamiaceae family and Galeopsis genus. An unequal quantitative distribution of the selected metabolites was observed within separate organs of the G. bifida plant, characterized by high accumulation of most compounds within the aerial part of the plant (leaves, flowers). Analysis of the content of specific chosen compounds within the leaves of different populations of G. bifida from Eastern Siberia revealed the existence of two chemical types based on metabolic specifics: the southern type accumulates flavone glucuronides, while the northern type tends to accumulate high levels of phenylpropanoids and acylated flavone glucosides. The first study of the bioactivity of G. bifida extract demonstrated that the herb has low toxicity in acute experiments and expresses antioxidant potential against free radicals in the form of DPPH˙, ABTS˙+, and superoxide radical, as well as high ferric reducing antioxidant power, oxygen radical absorbance capacity, and protective action in the carotene bleaching assay. In general, our results suggest the herb of G. bifida as a new, prospective synanthropic plant for medical application.

Highlights

Intensive use of natural landscapes and decreased areas of natural vegetation lead to the process of synanthropization, which has acquired the scale of anthropogenic evolution [1]
Elution of the preconditioned cartridge using water, ethanol, and alkalized ethanol allowed the isolatation of a hydrophilic fraction of iridoids and two less polar fractions of phenylethanoid glycosides/neutral flavone glycosides and acidic/acylated flavone glycosides
Owing to the high content of the phenolic compounds in G. bifida plant material and dry extracts (Table S2), especially compounds with expressed antioxidant potential, such as phenylethanoid glucosides [50], caffeoylquinic acids [100], and flavone glycosides [95], we studied the antioxidative properties of G. bifida methanol extracts (GBME) from eight Siberian populations

Summary

Introduction

Intensive use of natural landscapes and decreased areas of natural vegetation lead to the process of synanthropization, which has acquired the scale of anthropogenic evolution [1]. In connection with anthropogenic transformation, synanthropic species occupy an increasingly prominent place in the structure of biological diversity, which is especially important for the vast territories of Siberia and Asia [2]. Speaking of their practical importance, synanthropic species, as a rule, are not considered to be economically valuable due to the instability of their raw material base. These species are characterized by high reproductive energy as well as wide ranging ecological adaptability, which make. The study of prospective practical applications for synanthropic species will, in the future, solve the problem of their utilization and expand the range of useful plant species

Methods

Results

Conclusion