Comprehensive chemical profiling of Bassia indica Wight. aerial parts extract using UPLC-ESI-MS/MS, and its antiparasitic activity in Trichinella spiralis infected mice: in silico supported in vivo study

Discovery of potent anti-toxoplasmosis drugs from secondary metabolites in Citrus limon (lemon) leaves, supported in-silico study

Toxoplasmosis induced by Toxoplasma gondii is a well-known health threat, that prompts fatal encephalitis increased with immunocompromised patients, in addition, it can cause chorioretinitis, microcephaly, stillbirth in the fetus and even led to death. Standard therapy uses sulfadiazine and pyrimethamine drugs revealed beneficial results during the acute stage, however, it has severe side effects. UPLC-ESI-MS/MS used to explore C. limon MeOH ext. constituents, which revealed a list of 41 metabolites of different classes encompasses; unsaturated fatty acid, tricarboxylic acids, phenolic aldehyde, phenolic acids, phenolic glycosides, coumarins, sesquiterpene lactone, limonoid, steroid and flavonoids. C. limon MeOH ext. and the isolates reduced significantly the number of T. gondii tachyzoites. Consequently, histopathological examination, proved significant reduction in the number of mononuclear inflammatory cells in the kidney and liver sections, besides, lowering the number of shrunken and degenerative neurons in the brain sections of infected mice. Molecular docking study was performed targeted certain receptors, which are important for the life cycle fundamentals for the parasite mobility including invasion and egress, and further molecular dynamics simulation was conducted to get insights into the structural changes of the formed complexes, along with a pharmacophoric mapping approach, that confirmed the need for a free hydroxyl group and/or a phenolic substituted one, in order to form HB, Hyd/Aro and ML interactions, through which, cell cycle disruption via iron chelation, could be achieved. In addition, the ADMIT properties of all identified metabolites were predicted.

In Vitro Anthelmintic Effect of Mexican Plant Extracts and Partitions Against Trichinella spiralis and Strongyloides venezuelensis

Parasitic diseases represent a significant global public health concern. Two clinically important parasites of high prevalence rates are Trichinella spiralis and Strongyloides stercoralis. However, the limitations of currently used nematocidal drugs highlight the urgent need for novel treatment approaches. The present study investigated the in vitro nematocidal activity of methanol extracts from Amphipterygium adstringens, Artemisia ludoviciana, Cymbopogon citratus, Heterotheca inuloides, Jatropha dioica, Justicia spicigera, Larrea tridentata, Mimosa tenuiflora, Psacalium decompositum, Ruta chalepensis, Semialarium mexicanum, and Smilax aspera against T. spiralis L1 and S. venezuelensis L3 (model for S. stercoralis). Most of the plants showed antiparasitic activity, but R. chalepensis crude methanol extract showed the most potent nematocidal activity against both parasites, with a mean lethal concentration (LC50) of 28.2 µg/mL and a selectivity index (SI) of 22.4 for T. spiralis and an LC50 of 244.8 µg/mL and SI of 2.58 for S. venezuelensis. This extract was further separated into n-hexane, chloroform, and methanol partitions by continuous Soxhlet extractions. The n-hexane partition demonstrated the strongest activity against both parasites, with an LC50 of 147.6 µg/mL and an SI of 7.77 against T. spiralis and an LC50 of 39.2 µg/mL and an SI of 3.77 against S. venezuelensis. LC-MS/MS analysis identified coumarins as the main chemical class (53%), and chalepin represented this partition's most abundant compound (29.9%). Overall, this study confirmed the antiparasitic potential of medicinal plants commonly used in Mexico. In addition, it highlights the possibility of obtaining bioactive compounds from plants like R. chalepensis, or the other plants evaluated in this study, as novel treatments against parasitic diseases.

Pharmacognostic Evaluation, Chemical Characterization, and Antibacterial Activity of Bassia indica (Wight) A.J. Scott

Bassia indica (Wight) A.J. Scott is an Indian origin plant with documented medicinal and nutritional value, but has not been fully characterized yet. The present study was designed to establish pharmacognostic standards for the proper identification of the B. indica plant and its chemical characterization. The plant was standardized with World Health Organization (WHO) standardization tools and chemically characterized by Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC-MS) analysis. Antibacterial potential was assessed by the zone of inhibition and minimum inhibitory concentration (MIC), and molecular docking studies were also performed. Pharmacognostic evaluation established the macroscopic and microscopic parameters for the identification of whole plant and its powder. Physicochemical parameters were also set forth while quantitative phytochemical analysis showed that the ethyl acetate fraction had the highest quantity of phenols, flavonoids, and tannins. FTIR analysis showed several functional groups such as phenols, alkanes, and alcohols while 55 phytochemicals were identified in the GC-MS analysis of the crude fraction. The crude extract and other fractions showed marked antibacterial activity, while the ethyl acetate fraction showed the least MIC (1.95-31.25 mg/mL). Phytochemicals identified in the GC-MS showed good molecular docking interactions against the DNA gyrase subunit B of bacteria with binding energies ranging from -4.2 to -9.4 kcal/mol. The current study describes the pharmacognostic characterization and phytochemical profiling of B. indica and provides scientific evidence to support its use in infections.

Identification of Potential Therapeutics of Mentha Essential Oil Content as Antibacterial MDR Agents against AcrAB-TolC Multidrug Efflux Pump from Escherichia coli: An In Silico Exploration

Multidrug-resistant bacterial pathogens, such as E. coli, represent a major human health threat. Due to the critical need to overcome this dilemma, since the drug efflux pump has a vital function in the evolution of antimicrobial resistance in bacteria, we have investigated the potential of Mentha essential oil major constituents (1-19) as antimicrobial agents via their ability to inhibit pathogenic DNA gyrase and, in addition, their potential inhibition of the E. coli AcrB-TolC efflux pump, a potential target to inhibit MDR pathogens. The ligand docking approach was conducted to analyze the binding interactions of Mentha EO constituents with the target receptors. The obtained results proved their antimicrobial activity through the inhibition of DNA gyrase (1kzn) with binding affinity ΔG values between -4.94 and -6.49 kcal/mol. Moreover, Mentha EO constituents demonstrated their activity against MDR E. coli by their ability to inhibit AcrB-TolC (4dx7) with ΔG values ranging between -4.69 and -6.39 kcal/mol. The antimicrobial and MDR activity of Mentha EOs was supported via hydrogen bonding and hydrophobic interactions with the key amino acid residues at the binding site of the active pocket of the targeted receptors.

Anti-Helicobacter pylori, anti-biofilm activity, and molecular docking study of citropten, bergapten, and its positional isomer isolated from Citrus sinensis L. leaves

Introduction

Citrus sinensis L. is a candidate plant with promising antimicrobial potential. In the current study, the phytochemical investigation of C. sinensis leaf extract led to the isolation of three coumarins, namely bergapten, xanthotoxin, and citropten.

Methods

The chemical structures of the isolated coumarins were elucidated using NMR and ESI-MS techniques. The total aqueous ethanol leaf extract and the isolated coumarins were evaluated for their antimicrobial effects against Helicobacter pylori using the MTT-micro-well dilution method and its anti-biofilm activity using MBEC assay, as compared to clarithromycin.

Results

The results showed that citropten scored the lowest MIC value at 3.9 μg/mL and completely inhibited the planktonic growth of H. pylori. In addition, it completely suppressed H. pylori biofilm at 31.25 μg/mL. These findings have been supported by molecular docking studies on the active sites of the H. pylori inosine 5'-monophosphate dehydrogenase (HpIMPDH) model and the urease enzyme, showing a strong binding affinity of citropten to HpIMPDH with seven hydrogen bonds and a binding energy of -6.9 kcal/mol. Xanthotoxin and bergapten showed good docking scores, both at -6.5 kcal/mol for HpIMPDH, with each having four hydrogen bondings. Furthermore, xanthotoxin showed many hydrophobic interactions, while bergapten formed one Pi-anion interaction. Concerning docking in the urease enzyme, the compounds showed mild to moderate binding affinities as compared to the ligand. Thus, based on docking results and good binding scores observed with the HpIMPDH active site, an in-vitro HpIMPDH inhibition assay was done for the compounds. Citropten showed the most promising inhibitory activity with an IC50 value of 2.4 μM. Conclusion: The present study demonstrates that C. sinensis L. leaves are a good source for supplying coumarins that can act as naturally effective anti-H. pylori agents.