A new anti-inflammatory flavonoid glycoside from tetraena aegyptia

Highly Promiscuous Flavonoid Di-O-glycosyltransferases from Carthamus tinctorius L

Safflower (Carthamus tinctorius L.) has been recognized for its medicinal value, but there have been limited studies on the glycosyltransferases involved in the biosynthesis of flavonoid glycosides from safflower. In this research, we identified two highly efficient flavonoid O-glycosyltransferases, CtOGT1 and CtOGT2, from safflower performing local BLAST alignment. By constructing a prokaryotic expression vector, we conducted in vitro enzymatic reactions and discovered that these enzymes were capable of catalyzing two-step O-glycosylation using substrates such as kaempferol, quercetin, and eriodictyol. Moreover, they exhibited efficient catalytic activity towards various compounds, including flavones (apigenin, scutellarein), dihydrochalcone (phloretin), isoflavones (genistein, daidzein), flavanones (naringenin, glycyrrhizin), and flavanonols (dihydrokaempferol), leading to the formation of O-glycosides. The broad substrate specificity of these enzymes is noteworthy. This study provides valuable insights into the biosynthetic pathways of flavonoid glycosides in safflower. The discovery of CtOGT1 and CtOGT2 enhances our understanding of the enzymatic processes involved in synthesizing flavonoid glycosides in safflower, contributing to the overall comprehension of secondary metabolite biosynthesis in this plant species.

Structures, Sources, Identification/Quantification Methods, Health Benefits, Bioaccessibility, and Products of Isorhamnetin Glycosides as Phytonutrients

In recent years, people have tended to consume phytonutrients and nutrients in their daily diets. Isorhamnetin glycosides (IGs) are an essential class of flavonoids derived from dietary and medicinal plants such as Opuntia ficus-indica, Hippophae rhamnoides, and Ginkgo biloba. This review summarizes the structures, sources, quantitative and qualitative analysis technologies, health benefits, bioaccessibility, and marketed products of IGs. Routine and innovative assay methods, such as IR, TLC, NMR, UV, MS, HPLC, UPLC, and HSCCC, have been widely used for the characterization and quantification of IGs. All of the therapeutic effects of IGs discovered to date are collected and discussed in this study, with an emphasis on the relevant mechanisms of their health-promoting effects. IGs exhibit diverse biological activities against cancer, diabetes, hepatic diseases, obesity, and thrombosis. They exert therapeutic effects through multiple networks of underlying molecular signaling pathways. Owing to these benefits, IGs could be utilized to make foods and functional foods. IGs exhibit higher bioaccessibility and plasma concentrations and longer average residence time in blood than aglycones. Overall, IGs as phytonutrients are very promising and have excellent application potential.

UPLC-PDA-MS/MS Profiling and Healing Activity of Polyphenol-Rich Fraction of Alhagi maurorum against Oral Ulcer in Rats

Camelthorn, Alhagi maurorum Boiss, family Fabaceae has long been used in African folk medicine owing to its richness in pharmacologically active metabolites. The crude extract (CEAM), ethyl acetate fraction (EFAM) and n-butanol (BFAM) fraction of A. maurorum aerial parts were investigated for their total polyphenols and oral antiulcer activity using in-vitro and in-vivo models. The major phenolic compound was isolated from the polyphenol-rich EFAM fraction and identified by conventional and spectroscopic methods of analysis as isorhamnetin-3-O-rutinoside. Furthermore, standardization of EAFM using UPLC-PDA-UV quantified isorhamnetin-3-O-rutinoside as 262.91 0.57 g/mg of the fraction. Analysis of EFAM using UPLC-PDA-MS/MS revealed tentative identification of 25 polyphenolic compounds. EFAM exhibited the most potent free radical scavenging activity against DPPH, with an IC₅₀ (27.73 ± 1.85 µg/mL) and an FRAP value of (176.60 ± 5.21 μM Trolox equivalent (TE)/mg fraction) in comparison with CEAM and BFAM. Acetic acid-induced oral ulcers in a rat model were used to evaluate the healing properties of A. maurorum aerial parts. EFAM significantly decreased tumor necrosis factor-alpha (TNF-α) and interleukin-2 (IL-2) by 36.4% and 50.8%, respectively, in the ulcer tissues while, CEAM and BFAM exhibited lower activity at the same dose. In addition, EFAM led to a significant (p < 0.0001) rise in the expression of proliferating cell nuclear antigen (PCNA), a cell proliferation marker. A. maurorum exhibited a potent healing effect in acetic acid-induced oral ulcers in rats by mitigating the release of pro-inflammatory cytokines and improving PCNA expression.