Liquid chromatography–diode array detection–electrospray ionisation mass spectrometry/nuclear magnetic resonance analyses of the anti-hyperglycemic flavonoid extract of Genista tenera Structure elucidation of a flavonoid-C-glycoside

The anti-hyperglycemic flavonoid extract obtained from Genista tenera was first studied by liquid chromatography (LC)–diode array detection (DAD) which showed the presence of two major compounds. One of them was identified as genistein-7-O-glucoside. Luteolin-7-O-glucoside was detected as a minor constituent, while luteolin-7,3′-di-O-glucoside and rutin were found in trace amounts. LC–DAD–ESI–MS and NMR were used to confirm the structure of these compounds and allowed the elucidation of the structure of the unknown major compound, which is the flavonoid 5,7,4′-trihydroxyisoflavone-8-C-glucoside.info:eu-repo/semantics/publishedVersio

Validation and clinical application of an UHPLC method for simultaneous analysis of total homocysteine and cysteine in human plasma

Several studies indicate that high levels of homocysteine (Hcy) and L-cysteine (L-Cys) are independent risk factors for cardiovascular disease. The validation and clinical application of an ultra HPLC method for analysis ofHcy and L-Cys is described. The reported method is simple, sensitive, rapid, precise, and less aggressive than other previously reported methods. The effect of the derivatization reaction time, pH, and organic solvent contents in the mobile phase are described and discussed. Optimized conditions resulted in excellent peak shapes. Results of method validation showed a good linearity (r2 ≥ 0.993) over the investigated concentration ranges and were observed for both compounds. The LOD and LOQ were 0.05 M and 0.15 M for Hcy and 0.24 M and 0.80 M for L-Cys, respectively. Validation results proved that the method precision was good and the accuracy was satisfactory. This validated method was successfully applied in an epidemiological study to measure and compare the prevalence of Hcy and L-Cys high levels in plasma of Portuguese type 2 diabetic patients with and without angiopathy. The study results showed that prevalence of hyperhomocysteinemia and hypercysteinemia were at least two times higher in diabetic patients with angiopathy compared to diabetics without angiopathy.This study was funded by the research project PIC/IC/82957/2007 from “Fundação para a Ciência e a Tecnologia” (FCT

Coupling of nanofiltration and UV, UV/TiO2 and UV/H2O2 processes for the removal of anti-cancer drugs from real secondary wastewater effluent

The detection of anti-cancer drugs in surface waters at ng/L indicates that most wastewater treatment processes currently applied are not effective enough to remove these resilient compounds from wastewater. Therefore alternative treatment processes should be tested to avoid discharges in the environment of drugs that have been linked to genotoxic effects. The innovative contribution of this study stands in coupling nanofiltration with advanced oxidation processes to treat real secondary wastewater effluents spiked with 4 widely consumed anticancer drugs. Direct photolysis was found to be extremely effective to degrade etoposide and paclitaxel from the secondary effluent as well as from the highly concentrated retentate produced by nanofiltration. The two drugs were not detected after 10 min of exposure that corresponds to higher than 98% removals given the method detection limits by direct injection. This is equivalent to pseudo-first order degradation rate constants higher than 0.46 min−1, which, to the best of the author's knowledge, has not yet been reported for paclitaxel in the literature. However, none of the tested oxidation processes (UV, UV/TiO2 and UV/H2O2) using the reactor setup, exposure times and concentrations of TiO2 and H2O2 tested, were able to degrade cyclophosphamide or ifosfamide effectively. Compared to literature data, this is probably related to the low amount of photons received by the treated media. Finally important aggregation of catalyst particles was observed in secondary effluent, and photocatalysis had no advantage compared to the other two processes tested

Treatment of anticancer drugs in hospital and wastewater effluents using nanofiltration

Anticancer drugs are currently widely used for the treatment of cancer and have been detected in hospital effluents, wastewater treatment plant effluents and river water samples in concentrations up to the µg.L-1 range. Within the next two decades, the annual number of cancer cases is expected to rise, which will lead to an increase in the consumption of anticancer drugs. These drugs are extremely important due to their highly potent mechanism of action and their potential risk for humans and the environment. Therefore, the development of effective treatment options is crucial to avoid the release of these emerging contaminants in the aquatic environment. The aim of this study was to assess the viability of nanofiltration for remediation, using as benchmark two representative membranes (Desal 5DK and NF270) to remove four widely consumed anticancer drugs (paclitaxel, etoposide, cyclophosphamide and ifosfamide) from different matrices (laboratory grade water, synthetic urine and real secondary effluent). Experimental results showed that the Desal 5DK membrane is more effective than the NF270 membrane for the rejection of these compounds. It presented average rejections higher than 89% for all the target anticancer drugs spiked in synthetic urine and real secondary effluent, showing no significant matrix influence on the rejection results. Daphnia magna toxicity tests showed that the immobilization effect observed in the permeate samples was lower than the feed samples. The target compounds have very different structures and physico-chemical properties and thus the high effectiveness reported for the Desal 5DK membrane is a good indication of what can be expected to a multitude of compounds