Ultrasound-assisted extraction optimization and validation of ultra-performance liquid chromatographic method for the quantification of miquelianin in Cuphea glutinosa leaves

Optimization and validation of ultrasound application with a low-temperature method to analyze organochlorine pesticides in smuggled cigarette tobacco

This work presents the optimization and validation of a method to quantify organochlorine pesticides in tobacco samples from smuggled cigarettes using ultrasound application and low-temperature extraction. The combined approach was validated for 20 organochlorine pesticides, achieving recoveries between 73% and 116%, and a relative standard deviation of less than 20%. The method minimized the matrix effect in 65% of the organochlorine pesticides. The limits of detection and quantification varied from 2 to 60 ng g-1 and 120 to 190 ng g-1, respectively. The method was applied to the analysis of 18 brands of smuggled cigarettes. The organochlorine pesticides found in the samples were cis-chlordane (89%), p,p'-dichlorodiphenyldichloroethylene (DDD) and methoxychlor (78%), endosulfan sulfate (67%), heptachlor epoxide, and endosulfan II (61%). The concentrations of the organochlorine pesticides in this study were higher than those in a similar survey on cigarettes marketed in China. The ultrasound application and low-temperature extraction may be an efficient alternative to analyzing tobacco samples since it uses only one extraction solvent, requires low-cost equipment, does not require an additional clean-up step, reduces the environmental impact through minimal waste generation, and can detect low analyte concentrations.

UPLC-MS/MS method for the determination of voriconazole plasma concentration from pediatric patients with hematologic tumor: an application towards personalized therapy

Untreated invasive fungal infection (IFI) is one of the important risk factors affecting the prognosis of pediatric patients with hematologic tumor. Voriconazole (VOR) is the first line anti-fungal drug for the treatment of Aspergillus infections. In order to reduce the risk of adverse drug reaction while producing ideal anti-fungal effect, therapeutic drug monitoring (TDM) was performed to maintain VOR plasma concentration in a range of 1000 to 5500 ng/ml. In present study, a reliable, accurate, sensitive, and quick ultra-high performance liquid chromatograph-tandem mass spectrometry (UPLC-MS/MS) method was developed for determination of VOR level. Protein precipitation was performed using acetonitrile, and then the chromatographic separation was carried out by UPLC with C18 column using the gradient mobile phase made by 0.1% methanoic acid in acetonitrile (A) and 0.1% methanoic acid in water (B). In the selective reaction monitor mode, the mass spectrometric detection was carried out by an TSQ Endura triple quadruple mass spectrometer. The performance of this UPLC-MS/MS method was validated as per the National Medical Products Administration for Bioanalytical Method Validation. Additionally, the plasma concentrations of VOR in pediatric patients with hematologic tumor were detected by this method, and the analyzed results were used for personalized therapy.

Polyphenolic Composition and in Vitro Antihypertensive and Anti-Inflammatory Effects of Cuphea lindmaniana and Cuphea urbaniana

The present study investigates the chemical composition, anti-inflammatory, and antihypertensive activities, in vitro, from extracts of Cuphea lindmaniana and Cuphea urbaniana leaves. The extraction was performed ultrasound-assisted, and UHPLC/MS analysis was in positive mode ionization. The anti-inflammatory activity of the extracts and miquelianin were assayed at concentrations 0.001-10 μg/mL by chemotaxis on rat polymorphonuclear neutrophils. The antihypertensive activity was performed by angiotensin-converting enzyme (ACE) inhibition. From the nineteen proposed compounds, six of them are described for the first time in this genus. The extracts displayed antichemotactic effect with a reduction of 100 % of the neutrophil migration, in vitro, in most concentrations. The ACE-inhibition presented results ranging from 19.58 to 22.82 %. In conclusion, C. lindmaniana and C. urbaniana extracts contain a rich diversity of flavonoids and display in vitro anti-inflammatory and antihypertensive potential. Thus, this study could serve as a scientific baseline for further investigation, on developmental novel products with therapeutic actions.

Optimized ultrasound-assisted extraction of total polyphenols from Empetrum nigrum and its bioactivities

Optimization of ultrasound-assisted extraction (UAE) of total polyphenols (TPP) from Empetrum nigrum aerial parts was carried out by response surface methodology (RSM). The optimum UAE conditions of extraction time, extraction temperature, ethanol concentration, and solvent-to-material ratio were 21.38 min, 42.32 °C, 61.93% and 53.29:1 mL/g, respectively. Under the optimum conditions, the extraction yield of TPP was 32.17 ± 0.46 mg/g, which was 1.29-1.44 folds to those by the conventional extraction methods. In addition, the bioactivities of the extracts were investigated. Antioxidant activity test by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay revealed that the TPP extracts had a high potential for free radical scavenging activity. The TPP extracts showed remarkable antibacterial activity against both Gram-positive and Gram-negative strains, especially against Gram-positive strains. The evaluation of antitumor activity by the MTT assay and flow cytometric analysis indicated that the TPP extracts significantly inhibited B 16F 10 melanoma cell proliferation and effectively induced apoptosis of melanoma cells. These results demonstrate that E. nigrum aerial parts are rich in TPP and show great application potential in the pharmaceutical industry.

Development and Validation of a Method for Determining the Quercetin-3-O-glucuronide and Ellagic Acid Content of Common Evening Primrose (Oenothera biennis) by HPLC-UVD

Toward the standardization of common evening primrose (Oenothera biennis) sprout extract (OBS-E), we aimed to obtain indicator compounds and use a validated method. HPLC-UVD allowed simultaneous quantification of the indicator compounds quercetin-3-O-glucuronide and ellagic acid. The method was validated in terms of specificity, linearity, precision, accuracy, and limit of detection/limit of quantification (LOD/LOQ). High specificity and linearity was demonstrated, with correlation coefficients of 1.0000 for quercetin-3-O-glucuronide and 0.9998 for ellagic acid. The LOD/LOQ values were 0.486/1.472 μg/mL for quercetin-3-O-glucuronide and 1.003/3.039 μg/mL for ellagic acid. Intra-day and inter-day variability tests produced relative standard deviation for each compound of <2%, a generally accepted precision criterion. High recovery rate were also obtained, indicating accuracy validation. The OBS-E prepared using various concentrations of ethanol were then analyzed. The 50% ethanol extract had highest content of quercetin-3-O-glucuronide, whereas the 70% ethanol extract possessed the lowest. However, the ellagic acid content was highest in the 70% ethanol extract and lowest in the 90% ethanol extract. Thus, quercetin-3-O-glucuronide and ellagic acid can be used industrially as indicator compounds for O. biennis sprout products, and our validated method can be used to establish indicator compounds for other natural products.