LC-ESI-MS/MS analysis, toxicity and anti-anaemic activity of Rubia tinctorum L. aqueous extract

The present study investigated the chemical profile, toxicity, and anti-anaemic activity of Rubia tinctorum root aqueous extract against phenylhydrazine induced hemolytic anaemia. Phenolic compounds were analyzed by LC-ESI-MS/MS; acute toxicity test was evaluated by administering a single dose of 2,000 mg.kg-1 of the extract; anaemia was induced by administration of 40 mg phenylhydrazine by intraperitoneal injection for 2 days. Moreover, the anti-anaemic activity was evaluated by measuring the haematological parameters of rats treated with iron and aqueous extract for 15 days. The LC-ESI-MS/MS analysis results revealed the presence of 31 phytochemical compounds, among them, citric acid was found as the most abundant. No signs of toxicity or death were recorded, indicating that the LD50 of R. tinctorum root extract is higher than 2,000 mg.kg-1. Furthermore, the aqueous extract increased red blood cell levels by 69.82 and 71.67 % in the groups treated with 200 and 400 mg.kg-1 of the extract, respectively. Besides, a significant increase in hemoglobin from 12.05 ± 0.15 to 12.9 ± 0.52 g.dL-1 was noted in rats treated with 400 mg.kg-1 of extract. Thus, the data indicate that the root extract could be considered a natural source for the treatment of anaemia.

In Vitro Anti-Diabetic Activities and UHPLC-ESI-MS/MS Profile of Muntingia calabura Leaves Extract

Anti-diabetic compounds from natural sources are now being preferred to prevent or treat diabetes due to adverse effects of synthetic drugs. The decoction of Muntingia calabura leaves was traditionally consumed for diabetes treatment. However, there has not been any published data currently available on the processing effects on this plant’s biological activity and phytochemical profile. Therefore, this study aims to evaluate the effect of three drying methods (freeze-drying (FD), air-drying (AD), and oven-drying (OD)) and ethanol:water ratios (0, 50, and 100%) on in vitro anti-diabetic activities of M. calabura leaves. In addition, an ultrahigh-performance-liquid chromatography–electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) method was used to characterize the metabolites in the active extract. The FD M. calabura leaves, extracted with 50% ethanol, is the most active extract that exhibits a high α-glucosidase and α-amylase inhibitory activities with IC50 values of 0.46 ± 0.05 and 26.39 ± 3.93 µg/mL, respectively. Sixty-one compounds were tentatively identified by using UHPLC-ESI-MS/MS from the most active extract. Quantitative analysis, by using UHPLC, revealed that geniposide, daidzein, quercitrin, 6-hydroxyflavanone, kaempferol, and formononetin were predominant compounds identified from the active extract. The results have laid down preliminary steps toward developing M. calabura leaves extract as a potential source of bioactive compounds for diabetic treatment.

Light-responsive molecular switch based on cucurbit[7]uril and 1,1'-bis(benzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium dibromide displaying white light emission

By using 1H NMR, ESI-MS and UV spectra, novel light-responsive molecular switch constructed by 1,1’-bis(benzyl)-4-[2-(4-pyridyl)-vinyl]-pyridinium (12+) and cucurbit[7]uril (Q[7]) is demonstrated. The E- to Z-isomerization of double bond in 12+...