Phytochemical Profiles and In Vitro Immunomodulatory Activity of Ethanolic Extracts from Galium aparine L.

Abstract

Galium aparine L., family Rubiaceae, is a widely spread species in the Galium genus. The herb of G. aparine is part of folk remedies and dietary supplements. In this study, we analyzed the chemical composition and immunomodulatory activities of G. aparine herb ethanolic extracts obtained from the plant material by maceration with 20%, 60% or 96% ethanol. The contents of hydroxycinnamic acid derivatives, flavonoids and polyphenols were determined spectrophotometrically, with extractives and polysaccharides quantified gravimetrically. The qualitative composition was studied using UHPLC-DAD-MS/MS analysis; isolation not previously described in G. aparine quercetin rhamnoglucoside was carried out through column chromatography, and the immunomodulatory activity of extracts was determined in the reaction of lymphocyte blast transformation. Major constitutes of extracts were iridoids, i.e., monotropein, 10-desacetylasperulosidic acid and asperulosidic acid; p-hydroxybenzoic acid; hydroxycinnamic acid derivatives, i.e., 3-O-caffeoylquinic, 5-O-caffeoylquinic, 3,4-O-dicaffeoylquinic, 3,5-O-dicaffeoylquinic, 4,5-O-dicaffeoylquinic acids and caffeic acid derivatives; flavonoids, i.e., rutin, quercetin 3-O-rhamnoglucoside-7-O-glucoside, and isorhamnetin 3-O-glucorhamnoside. Significantly, quercetin 3-O-rhamnoglucoside-7-O-glucoside was first isolated and identified in Galium species so far investigated. All G. aparine herb ethanolic extracts stimulate the transformational activity of immunocompetent blood cells, with 96% ethanolic extract being the most active. The data obtained necessitate further research into the mechanisms of immunomodulatory activity of extracts from G. aparine herb.Specific immunostimulants include thymus preparations, interleukins, interferons, biologically active peptides, polysaccharides of certain fungi and therapeutic vaccines, whose effect is explained through their ability to influence the metabolism of cells and body tissues and activate immunocompetent cells.Many plant-derived compounds, like sterols, polysaccharides, alkaloids, flavonoids, lectins and glycoprotein, are used for immunomodulation [3]. For example, among polysaccharides, acidic arabinogalactan and ramnogalacturonan have been shown to manifest immunostimulatory effect in vitro and in vivo [4]. Numerous studies look into the immunomodulative activities of saponins [5][6][7][8].The proven effect of triterpenoid glycosides on the immune system of mammals contributed to the development of a wide range of dietary supplements for the prevention of the immune system disturbances, i.e., human immunity system enhancement [9], and for the prevention and treatment of allergies [10,11].In our previous studies, the immunomodulative effect of the aqueous and ethanolic extracts of Galium verum L. herb was established [12,13]. Among other species of the genus Galium L., one of the most widely spread is Galium aparine L., also called cleavers or goosegrass, which can be found all over Ukraine, Europe, Northern America and certain parts of Asia; i...

Content of Bioactive Constituents and Antioxidant Potential of Galium L. species

“…Many species from this genus, including the investigated G. palustre, G. mollugo and G. verum, share additional flavonoids such as isorhoifolin, palustroside and cosmosiin, while even more flavonoids seem to be shared by the last two species. [33] This is in line with their much closer relationship compared to G. palustre (G. sect. Aparinoides).…”

“…[26] Naturally, as members of different sections, G. mollugo and G. verum may contain their own distinctive flavonoids. [13,32,33] The spectrophotometric results, however, were not completely consistent with the results of qualitative phytochemical analyses (Table 1). For instance, G. parisiense, contained least flavonoids according to the spectrophotometric assay, while in the phytochemical screening based on a simple color reaction with sodium hydrogen it was not remarkably different from the species in which much higher flavonoid concentrations were recorded.…”

“…These results suggest that antiradical capacities of selected Galium species are highly dependent on their flavonoid levels. Rutin (quercetin 3-O-rutinoside), being not only a common flavonoid of Galium species, [33] but also the predominant one, [13] might have contributed to the observed activity to a greater extent. However, according to recent findings, rutin values in G. verum can greatly exceed those in G. mollugo and related species such as G. aparine and G. odoratum, [13] members of the G. sect.…”

Phytochemical study of Salvia grandiflora and Salvia officinalis leaves for establishing prospects for use in medical and pharmaceutical practice

“…The study of the composition of phenolic compounds was performed by HPLC on a Shimadzu LC20 Prominence chromatograph in a modular system equipped with a four-channel pump LC20AD, thermostat STO20A column, automatic SIL20A sampler, diodematrix detector SPDM20A and ChemStation LC18 and ChemStation LC 250 mm x 4.6 mm, particle size 5 μm; column temperature -35 °C; detection wavelength -330 nm (for hydroxycinnamic acids, flavonoid glycosides), 370 nm (for flavonoid aglycones), 280 nm (for tannins), 340 nm (coumarins); the flow rate of the mobile phase is 1 ml / min; sample volume injected -5 µl; mobile phase: eluent A: 0.1 % trifluoroacetic acid solution in water; eluent B: 0.1 % trifluoroacetic acid solution in acetonitrile. The identification of the components was performed by the retention time and the compliance of the UV spectra with the substance standards [23, [26][27][28].…”

Immunomodulatory Activity and Phytochemical Profile of Infusions from Cleavers Herb

“…Our previous research on ethanolic extracts from cleavers indicated that they have some immunostimulatory activity. It was also shown that ethanolic extract consist of mainly chlorogenic acid derivatives, flavonoids and some iridoids [18].…”