Determination of Five Major 8-Prenylflavones in Leaves of Epimedium by Solid-Phase Extraction Coupled with Capillary Electrophoresis

Recent Applications of Capillary Electrophoresis in the Determination of Active Compounds in Medicinal Plants and Pharmaceutical Formulations

The present review summarizes scientific reports from between 2010 and 2019 on the use of capillary electrophoresis to quantify active constituents (i.e., phenolic compounds, coumarins, protoberberines, curcuminoids, iridoid glycosides, alkaloids, triterpene acids) in medicinal plants and herbal formulations. The present literature review is founded on PRISMA guidelines and selection criteria were formulated on the basis of PICOS (Population, Intervention, Comparison, Outcome, Study type). The scrutiny reveals capillary electrophoresis with ultraviolet detection as the most frequently used capillary electromigration technique for the selective separation and quantification of bioactive compounds. For the purpose of improvement of resolution and sensitivity, other detection methods are used (including mass spectrometry), modifiers to the background electrolyte are introduced and different extraction as well as pre-concentration techniques are employed. In conclusion, capillary electrophoresis is a powerful tool and for given applications it is comparable to high performance liquid chromatography. Short time of execution, high efficiency, versatility in separation modes and low consumption of solvents and sample make capillary electrophoresis an attractive and eco-friendly alternative to more expensive methods for the quality control of drugs or raw plant material without any relevant decrease in sensitivity.

Isomeric flavonoid aglycones derived from Epimedii Folium exerted different intensities in anti-osteoporosis through OPG/RANKL protein targets

Two Epimedium-derived isomeric flavonoids, CIT and IT, had the therapeutic effect in osteopenic rats. However, it is difficult to expound their activity differences in anti-osteoporosis. This paper contrasted their anti-osteoporosis activity from the perspective of their affinity to OPG/RANKL protein targets. Molecular docking indicated that both of CIT and IT could interact with the hydrophobic pockets of OPG/RANKL, while CIT was easier and more stable to combine with RANKL. On the contrary, compared with CIT, IT was more inclined to combine with OPG and stay away from combining with RANKL. Subsequently, whether the interaction between isomeric flavonoids and OPG/RANKL targets promoted or suppressed bone resorption was undefined and which was validated by zebrafish embryo and ovariectomized rats in this paper. Compared with IT, the staining area and cumulative optical density of zebrafish skeleton were significantly increased after the treatment of CIT (0.1 μM, p < 0.05). Furthermore, CIT mainly reflected a more significant role in upregulating OPG (p < 0.05), downregulating RANKL (p < 0.05), reducing serum AKP and TRACP level (p < 0.05), enhancing bone biomechanical properties (p < 0.05), increasing bone mineral density (p < 0.05) and improving trabecular bone microarchitecture (p < 0.05) in osteoporotic rats. In conclusion, the combination of isomeric flavonoids (CIT/IT) and OPG/RANKL targets attenuated the excitation effects of OPG or RANKL on RANKL. Because CIT was more firmly combined with RANKL than IT, CIT had stronger anti-osteoporosis effect by inhibiting bone resorption.