Evaluation of pesticide residues in commercial Swiss beeswax collected in 2019 using ultra-high performance liquid chromatographic analysis

The aim of this study was to determine residue levels of pesticides in Swiss commercial beeswax. Foundation samples were collected in 2019 from nine commercial manufacturers for analysis of 21 pesticides using ultra-high performance liquid chromatography. Individual samples showed the variability and residue ranges and pooled samples represented the average annual residue values of the Swiss production. In total, 17 pesticides were identified and 13 pesticides were quantified. They included 13 acaricides and/or insecticides, two fungicides as well as a synergist and a repellent. The means calculated from individual samples were similar to the average annual residue values for most tested pesticides. Mean values of 401, 236, 106 and 3 μg·kg−1 were obtained for the beekeeping-associated contaminants coumaphos, tau-fluvalinate, bromopropylate and N-(2,4-Dimethylphenyl)-formamide (DMF; breakdown product of amitraz), respectively. For the other pesticides, the mean values were 203 μg·kg−1 (synergist piperonyl butoxide), 120 μg·kg−1 (repellent N,N-Diethyl-3-methylbenzamide, DEET), 19 μg·kg−1 (chlorfenvinphos) and 4 μg·kg−1 ((E)-fenpyroximate), while the means for acrinathrin, azoxystrobin, bendiocarb, boscalid, chlorpyrifos, flumethrin, permethrin, propoxur and thiacloprid were below the limit of quantification (< LOQ). Individual samples contained from seven to 14 pesticides. The ranges of values for coumaphos and piperonyl butoxide (from 14 to 4270 μg·kg−1; from 6 to 1555 μg·kg−1, respectively) were larger as compared to the ranges of values for DEET and tau-fluvalinate (from < LOQ to 585 μg·kg−1; from 16 to 572 μg·kg−1, respectively). In conclusion, the most prominent contaminants were the pesticides coumaphos and tau-fluvalinate, which are both acaricides with previous authorization for beekeeping in Switzerland, followed by piperonyl butoxide, a synergist to enhance the effect of insecticides. Graphical abstract

Phytochemical Profile of Opuntia ficus-indica (L.) Mill Fruits (cv. ‘Orito’) Stored at Different Conditions

This research analyzed the phytochemical profile of prickly pear fruits from ‘Orito’ cultivar stored under cold conditions (2 °C, 85–90% RH) and shelf-life conditions at room temperature (stored at 20 °C for three days after cold storage) for 28 days, mimicking the product life cycle. A total of 18 compounds were identified and quantitated through HPLC-DAD-MS/MS (High-Performance Liquid Chromatographic -Diode Array Detector- Mass Spectrometry) analyses. Phenolic acids such as eucomic acid and betalains such as indicaxanthin were the predominant chemical families, and piscidic acid was the most abundant compound. During cold storage, the content of eucomic acid isomer/derivative and syringaresinol increased, and citric acid decreased, which could be caused by the cold activation of the phenylalanine ammonia-lyase (PAL) and polyphenol oxidase (PPO) enzymes. However, no significant differences were found in the content of these compounds during shelf-life storage. These results showed that ‘Orito’ fruit marketability would be possible up to 28 days after harvesting, retaining its profile, which is rich in bioactive compounds.

Cones of coniferous taxa as a potential source of bioactive polyphenols

Background: Coniferous cones are a by-product of forestry and wood logging, used for many possible purposes, e.g., the extraction of polyphenols. Objective: The aim of the present article was the comparison of the antioxidant polyphenol content of the differently matured cones of 17 selected conifers, either common in Hungary or yet uninvestigated. Methods: Total polyphenol content, ferric reducing antioxidant power and 2,2-diphenyl-1-picrylhydrazyl assays were used to determine the antioxidant contents. A scoring system was implemented using the three assay results to evaluate and compare the overall antioxidant power of the samples. Result and Conclusion: Highest antioxidant contents were found in green cones, followed by mature and opened cones. Taxa with the highest scores were Tsuga canadensis, Cryptomeria japonica, Chamaecyparis lawsoniana, Thuja orientalis, Metasequoia glyptostroboides and Picea abies. For the samples with the highest overall antioxidant power the high-performance liquid chromatographic/tandem mass spectrometric polyphenol profiling was carried out (green cones of T. canadensis and P. abies) and 83 compounds have been tentatively identified and described. Results contribute to the future bioactivity testing and evaluation of the cone extracts of T. canadensis and P. abies.

Development of High Performance Liquid Chromatographic Estimation of Domperidone and Lansoprazole

The combination of Domperidone and Lansoprazole is very useful in Gastro-esophageal disinfection (Dyspepsia). These methods provide means to separate the components characterize and quantify the components. An accurate, precise, specific and simple HPLC method was developed for simultaneous estimation of Domperidone and Lansoprazole. By this method retention time, linearity and accuracy data is respectively found for Domperidone and Lansoprazole. Mobile phase was prepared by mixing 51 volume of Acetonitrile and 49 volume of Ammonium Acetate (51:49 V/V) then 25mg each of Domperidone and Lansoprazole was dissolved in small volume of Acetonitrile: Ammonium Acetate (51:49 V/V) separately. Retention time was recorded 4.330 ± 0.003 minute and 5.820 ± 0.003 minute for Domperidone and Lansoprazole with 1.0 ml/min flow rate. The low value of % R.S.D indicates that this method is precise and accurate. Thus it can be concluded that the proposed method was good approach for obtaining reliable result.

Laelia furfuracea Lindl.: an Endemic Mexican Orchid with Anticoagulant Activity

Laelia furfuracea is an endemic orchid from Mexico, with antioxidant activity. The objective of this study was to evaluate the effect of hydroethanolic extract and fractions obtained from the orchid leaves on the clotting times of patients with venous thromboembolic disease (VTD) and to identify their tentative compounds. The anticoagulant activity was evaluated by determining prothrombin (PT), thrombin (TT) and, activated partial thromboplastin (APTT) times. Identification of the compounds was carried out using a chromatographic technique with an ultra-high-performance liquid chromatographic analyzer coupled with electrospray ionization with quadrupole time of flight-mass-mass spectrometry. The extract prolonged the clotting times depending on the concentration-response (5-60 mg / mL); 25 mg/mL prolonged the PT (33.2 ± 2.3 s) and TT (33.1 ± 0.3 s); and APTT (61.8 ± 3.4 s) at a concentration of 15 mg/mL. The main groups tentatively identified were xanthine, carboxylic acid, amino acid, and phenolic compounds. These compounds or the synergy between them prolong clotting times. Laelia furfuracea is an orchid with research potential in the search for new anticoagulant agents. Resumen. Laelia furfuracea es una orquídea endémica de México, la cual posee actividad antioxidante. El objetivo de este estudio fue evaluar el efecto del extracto hidroetanólico y fracciones obtenidas de hojas de la orquídea sobre los tiempos de coagulación de pacientes con enfermedad tromboembólica venosa (ETV) e identificar sus posibles compuestos. La actividad anticoagulante se evaluó determinando los tiempos de protrombina (TP), trombina (TT) y tromboplastina parcial activada (TTPA). La identificación de los compuestos se realizó usando una técnica cromatográfica con un analizador cromatográfico líquido de Ultra Alta Resolución con Ionización por electroespray acoplado a espectrometría de masas con Cuadrupolo y Tiempo de Vuelo. El extracto prolongó los tiempos de coagulación dependiente de la concentración-respuesta (5-60 mg/mL); 25 mg/mL prolongó el TP (33.2±2.3 s) y TT (33.1±0.3 s); y TTPA (61.8±3.4 s) a una concentración de 15 mg/mL. Los principales grupos de posibles compuestos identificados fueron xantina, ácido carboxílico, aminoácido y compuestos fenólicos. Estos compuestos o la sinergia entre ellos prolongan los tiempos de coagulación. Laelia furfuracea es una orquídea con potencial en investigación para la búsqueda de nuevos agentes anticoagulantes.

Development & Validation of RP-HPLC Method for the Estimation of Doravirine in Bulk and Pharmaceutical Dosage Form

A simple, accurate, rapid and precise isocratic reversed phase high-performance liquid chromatographic method has been developed and validated for determination of Doravirine in tablets. The chromatographic separation was carried out on Dionex C18 (250 x 4.6mm, 5µ) with a mixture of methanol: 0.05M potassium dihydrogen phosphate (40:60%v/v) as a mobile phase at a flow rate of 1.5 mL/min. UV detection was performed at 306 nm. The retention time was 5.24 min for Doravirine. Calibration plot was linear (r2=0.999) over the concentration range of 200-600 µg/mL. The method was validated for accuracy, precision, specificity, linearity, robustness, LOD and LOQ. The proposed method was successfully used for quantitative analysis of tablets. No interference from any component of pharmaceutical dosage form was observed. Validation studies revealed that method is specific, rapid, reliable, and reproducible. The high recovery and low relative standard deviation confirm the suitability of the method for routine determination of Doravirine in bulk and tablet dosage form.