The development and validation of an HPLC-MS/MS method for the determination of eriocitrin in rat plasma and its application to a pharmacokinetic study

Bio-fabricated zinc oxide nanoparticles mediated by endophytic fungus Aspergillus sp. SA17 with antimicrobial and anticancer activities: in vitro supported by in silico studies

Introduction

In recent years, the world's attention has been drawn to antimicrobial resistance (AMR) because to the frightening prospect of growing death rates. Nanomaterials are being investigated due to their potential in a wide range of technical and biological applications.

Methods

The purpose of this study was to biosynthesis zinc oxide nanoparticles (ZnONPs) using Aspergillus sp. SA17 fungal extract, followed by characterization of the produced nanoparticles (NP) using electron microscopy (TEM and SEM), UV-analysis, X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FT-IR).

Results and Discussion

The HR-TEM revealed spherical nanoparticles with an average size of 7.2 nm, and XRD validated the crystalline nature and crystal structure features of the generated ZnONPs, while the zeta potential was 18.16 mV, indicating that the particles' surfaces are positively charged. The FT-IR was also used to identify the biomolecules involved in the synthesis of ZnONPs. The antibacterial and anticancer properties of both the crude fungal extract and its nano-form against several microbial strains and cancer cell lines were also investigated. Inhibition zone diameters against pathogenic bacteria ranged from 3 to 13 mm, while IC50 values against cancer cell lines ranged from 17.65 to 84.55 M. Additionally, 33 compounds, including flavonoids, phenolic acids, coumarins, organic acids, anthraquinones, and lignans, were discovered through chemical profiling of the extract using UPLC-QTOF-MS/MS. Some molecules, such pomiferin and glabrol, may be useful for antibacterial purposes, according to in silico study, while daidzein 4'-sulfate showed promise as an anti-cancer metabolite.

Eriocitrin: A review of pharmacological effects

The present study aimed to recognize the recent literature to highlight the pharmacological impacts and highlight the therapeutic potential of the active molecule eriocitrin. Citrus limon are a good resource of the flavanone eriocitrin (eriodictyol 7-O-β-D-rutinoside). Eriocitrin has potent biological actions due to its strong antioxidant, antitumor, anti-allergic, antidiabetic and anti-inflammatory activities. Eriocitrin is more potent in suppressing oxidative stress in diabetes mellitus (DM) and other chronic diseases incurred by excessive oxidative stress. During metabolism, eriocitrin is metabolized by gut microbiota, and a chain of molecules such as eriodictyol, methy-eriodictyol, 3,4-dihydroxyhydrocinnamic acid (DHCA), and much more conjugated molecules. More in-depth studies are recommended to explore this drug for clinical trials.

Spontaneous conversion of prenyl halides to acids: application in metal-free preparation of deuterated compounds under mild conditions

Here we reveal a simple generation of deuterium halide (DX) from common and inexpensive reagents readily available in a synthetic chemistry laboratory, i.e. prenyl-, allyl-, and propargyl halides, under mild conditions. We envisaged that in situ generation of an acid, deuterium halide, would be useful for acid-catalyzed reactions and could be employed for organocatalytic deuteration. The present work reports a metal-free method for deuterium labeling covering a broad range of substrate including phenolic compounds (i.e. flavonoids and stilbenes), indoles, pyrroles, carbonyl compounds, and steroids. This method was also applied for commonly used drugs such as loxoprofen, haloperidol, stanolone, progesterone, androstenedione, donepezil, ketorolac, adrenosterone, cortisone, pregnenolone, and dexamethasone. A gram-scale chromatography-free synthesis of some deuterated compounds is demonstrated in this work. This work provides a simple, clean and by-product-free, site-selective deuteration, and the deuterated products are obtained without chromatographic separation. When applying these initiators for other acid-catalyzed reactions, the deuterium isotope effects of DX may provide products which are different from those obtained from reactions using common acids. Although the mechanism of the spontaneous transformation of prenyl halides to acid is unclear, this overlooked chemistry may be useful for many reactions.

Simultaneous Quantification of Four Compounds in Rat Plasma by HPLC-MS/MS and Its Application to Pharmacokinetic Study after Oral Administration of Pomegranate Flowers

Pomegranate flowers (PFs) were reported to possess various biological activities such as antidiabetic, anti-inflammatory and hepatoprotective activities, and using to treat diabetes. Although chemical constituents and pharmacological activities of PFs have been studied, unfortunately, there was no report on the pharmacokinetic profile of PFs in vivo. In this study, a selective high-performance liquid chromatography triple quadrupole tandem mass spectrometry (HPLC-QQQ-MS/MS) method was developed and validated for simultaneous quantification of four compounds (corilagin, ellagic acid, gallic acid and brevifolincarboxylic acid) in rat plasma after oral administration of PFs. The good linearity concentration ranges for the four analytes were from 2.5 to 3000 ng/mL with coefficient value R2 > 0.99 in calibration curves. The intra- and inter-day accuracy of the four analytes was in the range of 85.33-102.50%, with relative standard deviation (RSD) of <14.81%. The stability results showed that accuracy of the four analytes was in the range of 81.88-104.74%, with RSD of <14.86%. The validation method was successfully applied to pharmacokinetic profiles of the four analytes in rats after oral administration of PFs extract. This pharmacokinetic study can provide better understanding to clarify in vivo mechanisms of PFs and may facilitate its further development as therapeutic agent.

Assessment of a developed HPLC-MS/MS approach for determining plasma eupatorin in rats and its application in pharmacokinetics analysis

Eupatorin, a bioactive compound extracted from Java tea (Orthosiphon stamineus), possesses potent anti-cancer, anti-inflammatory and vasodilation activities. To date, no pharmacokinetics studies on eupatorin have yet been performed. Here, we established and validated a sensitive and selective LC-MS/MS (liquid chromatography-tandem mass spectrometry) approach for determining plasma eupatorin in rats. Chromatographic fractionation was conducted on a Wonda Cract ODS-2 C18 Column (4.6 mm × 150 mm, 5 μm) with a mobile phase containing aqueous 0.1% formic acid and acetonitrile using a flow rate of 0.8 ml min⁻¹. In multiple reaction monitoring mode, precursor-to-product ion transitions for quantification of eupatorin and the internal standard were set at 343.1 → 328.1 and 252.0 → 155.9, respectively. The intra- and inter-day precision and accuracy were found to be below 6.72% and within ±8.26% in rat plasma, respectively. Meanwhile, all values of the matrix effect, recovery and stability were within the accepted ranges. Furthermore, we carried out the pharmacokinetic analysis using the developed method. The pharmacokinetic study revealed that while the C_max (maximum plasma concentration) of eupatorin and time for reaching the C_max (T_max) were 974.886 ± 293.898 μg L⁻¹ and 0.25 h, respectively, the half-life was 0.353 ± 0.026 h. This study will be of great significance to the research on the pharmacology, clinical pharmacy and drug action mechanism of eupatorin.

Eupatorin, a bioactive compound extracted from Java tea (Orthosiphon stamineus), possesses potent anti-cancer, anti-inflammatory and vasodilation activities.