New C,O-Glycosylflavones from Melandrium divaricatum

Isolation, NMR Characterization, and Bioactivity of a Flavonoid Triglycoside from Anthyllis henoniana Stems: Antioxidant and Antiproliferative Effects on MDA-MB-231 Breast Cancer Cells

Plant extracts are considered as a large source of active biomolecules, especially in phytosanitary and pharmacological fields. Anthyllis henoniana is a woody Saharan plant located in the big desert of North Africa. Our previous research paper proved the richness of the methanol extract obtained from the stems in flavonoids and phenolic compounds as well as its remarkable antioxidant activity. In this research, we started by investigating the phytochemical composition of the methanol extract using high performance liquid chromatography coupled with electrospray ionization mass spectrometry (LC-MS/MS). Among the 41 compounds identified, we isolated and characterized (structurally and functionally) the most abundant product, a flavonoid triglycoside (AA770) not previously described in this species. This compound, which presents no cytotoxic activity, exhibits an interesting cellular antioxidant effect by reducing reactive oxygen species (ROS) generation, and an antiproliferative action on breast cancer cells. This study provides a preliminary investigation into the pharmacological potential of the natural compound AA770, isolated and identified from Anthyllis henoniana for the first time.

Recent Advances on Natural Aryl-C-glycoside Scaffolds: Structure, Bioactivities, and Synthesis-A Comprehensive Review

Aryl-C-glycosides, of both synthetic and natural origin, are of great significance in medicinal chemistry owing to their unique structures and stability towards enzymatic and chemical hydrolysis as compared to O-glycosides. They are well-known antibiotics and potent enzyme inhibitors and possess a wide range of biological activities such as anticancer, antioxidant, antiviral, hypoglycemic effects, and so on. Currently, a number of aryl-C-glycoside drugs are on sale for the treatment of diabetes and related complications. This review summarizes the findings on aryl-C-glycoside scaffolds over the past 20 years, concerning new structures (over 200 molecules), their bioactivities-including anticancer, anti-inflammatory, antioxidant, antivirus, glycation inhibitory activities and other pharmacological effects-as well as their synthesis.

Caucasian Gentiana Species: Untargeted LC-MS Metabolic Profiling, Antioxidant and Digestive Enzyme Inhibiting Activity of Six Plants

The members of Gentiana genus are widely distributed in the Caucasus region where they are used as phytoremedies, but they still have not been studied for their chemical composition and bioactivity. High-performance liquid chromatography with diode array and electrospray triple quadrupole mass detection (HPLC-DAD-ESI-QQQ-MS) was used to investigate metabolites of herb and roots of six gentians (Gentiana asclepiadea, G. cruciata, G. gelida, G. paradoxa, G. pneumonanthe, G. septemfida) grown in the Caucasus. In total, 137 compounds were found including three carbohydrates, 71 iridoid glycosides (mostly loganic acid), loganin, swertiamarin, gentiopicroside and sweroside derivatives, 40 flavones C-, O-, C,O-glycosides (such as luteolin, apigenin, chrysoeriol, and acacetin derivatives), two phenolic O-glycosides, five hydroxycinnamates, eight xanthones, and seven triterpene glycosides. Most of these compounds were identified in gentian samples for the first time. Quantitative differences were found in levels of seven iridoid glycosides, nine glycosylflavones, and two xanthones obtained by HPLC-DAD assay. The gentian extracts were evaluated for their radical-scavenging properties against DPPH and superoxide anion radicals, lipid peroxidation inhibition, and α-amylase/α-glycosidase inhibition. The herb extracts showed higher activity than root extracts. Positive correlations were found between the content of quantified phenolics and antioxidant and digestive enzymes inhibiting activity. The findings presented in our work suggest that the Caucasian gentians are a good source of bioactive phytocompounds with antioxidant and antidiabetic potential.