Biological Efficacy of Compounds from Stingless Honey and Sting Honey against Two Pathogenic Bacteria: An In Vitro and In Silico Study

Honey inhibits bacterial growth due to the high sugar concentration, hydrogen peroxide generation, and proteinaceous compounds present in it. In this study, the antibacterial activity of stingless and sting honey against foodborne pathogenic bacteria isolated from spoiled milk samples was examined. The isolated bacterial strains were confirmed as Bacillus cereus and Listeria monocytogenes through morphological, biochemical, and 16 s RNA analysis. Physiochemical characterizations of the honey samples revealed that both of the honey samples had an acidic pH, low water content, moderate reducing sugar content, and higher proline content. Through the disc diffusion method, the antibacterial activities of the samples were assayed and better results were observed for the 50 mg/disc honey. Both stingless and sting honey showed the most positive efficacy against Bacillus cereus. Therefore, an in silico study was conducted against this bacterium with some common compounds of honey. From several retrieved constituents of stingless and sting honey, 2,4-dihydroxy-2,5-dimethyl 3(2H)-furan-3-one (furan) and 4H-pyran-4-one,2,3-dihydro of both samples and beta.-D-glucopyranose from the stingless revealed high ligand-protein binding efficiencies for the target protein (6d5z, hemolysin II). The root-mean-square deviation, solvent-accessible surface area, the radius of gyration, root-mean-square fluctuations, and hydrogen bonds were used to ensure the binding stability of the docked complexes in the atomistic simulation and confirmed their stability. The combined effort of wet and dry lab-based work support, to some extent, that the antimicrobial properties of honey have great potential for application in medicine as well as in the food industries.     

Seawater Splitting for Hydrogen Generation Using Zirconium and Its Niobium Alloy under Gamma Radiation

Hydrogen production is produced for future green energy. The radiation–chemical yield for seawater without a catalyst, with Zr, and with Zr1%Nb (Zr = 99% Nb = 1%) were (G(H₂) = 0.81, 307.1, and 437.4 molecules/100 eV, respectively. The radiation–thermal water decomposition increased in γ-radiation of the Zr1%Nb + SW system with increasing temperature. At T = 1273 K, it prevails over radiation processes. During the radiation and heat radiation heterogeneous procedures in the Zr1% Nb + SW system, the production of surface energetic sites and secondary electrons accelerated the accumulation of molecular hydrogen and Zr1%Nb oxidation. Thermal radiation and thermal processes caused the metal phase to collect thermal surface energetic sites for water breakdown and Zr 1%Nb oxidation starting at T = 573 K.     

Europinidin Inhibits Rotenone-Activated Parkinson’s Disease in Rodents by Decreasing Lipid Peroxidation and Inflammatory Cytokines Pathways

Background: Europinidin is a derivative of delphinidin obtained from the plants Plumbago Europea and Ceratostigma plumbaginoides. This herb has wide medicinal applications in treating various diseases but there are very few studies available on this bioactive compound. Considering this background, the present study is designed for the evaluation of Europinidin against Parkinson’s disease. Aim: The investigation aims to assess the effect of Europinidin in the rotenone-activated Parkinson’s paradigm. Methods: To evaluate neuroprotective activity, rotenone (1.5 mg/kg s.c) and europinidin (10 mg/kg and 20 mg/kg) was administered in rats for 21 days. The behavioural parameters were performed before sacrificing the rats. On the 22nd day, all the rats were assessed for biochemical markers (SOD, GSH, MDA, Catalase), neurotransmitter levels (Dopamine, 5-HIAA, DOPAC, and HVA levels), and neuroinflammatory markers (IL-6, IL-1β and TNF-α). Results: It was found that rotenone produced significant (p < 0.001) oxidative damage, a cholinergic deficit, dopaminergic loss, and a rise in neuroinflammatory markers in rats. Conclusion: The study concludes that europinidin possesses anti-oxidant and anti-inflammatory properties. The results suggest the therapeutic role of europinidin against rotenone-activated behavioural, biochemical, and neuroinflammatory alterations in rats.     

X-ray Structures and Computational Studies of Two Bioactive 2-(Adamantane-1-carbonyl)-N-substituted Hydrazine-1-carbothioamides

Two biologically active adamantane-linked hydrazine-1-carbothioamide derivatives, namely 2-(adamantane-1-carbonyl)-N-(tert-butyl)hydrazine-1-carbothioamide) 1 and 2-(adamantane-1-carbonyl)-N-cyclohexylhydrazine-1-carbothioamide 2, have been synthesized. X-ray analysis was conducted to study the effect of the t-butyl and cyclohexyl moieties on the intermolecular interactions and conformation of the molecules in the solid state. X-ray analysis reveals that compound 1 exhibits folded conformation, whereas compound 2 adopts extended conformation. The Hirshfeld surface analysis indicates that the contributions of the major intercontacts involved in the stabilization of the crystal structures do not change much as a result of the t-butyl and cyclohexyl moieties. However, the presence and absence of these contacts is revealed by the 2D-fingerprint plots. The CLP–Pixel method was used to identify the energetically significant molecular dimers. These dimers are stabilized by different types of intermolecular interactions such as N–H···S, N–H···O, C–H···S, C–H···O, H–H bonding and C–H···π interactions. The strength of these interactions was quantified by using the QTAIM approach. The results suggest that N–H···O interaction is found to be stronger among other interactions. The in vitro assay suggests that both compounds 1 and 2 exhibit urease inhibition potential, and these compounds also display moderate antiproliferative activities. Molecular docking analysis shows the key interaction between urease enzyme and title compounds.     

Synthesis,Antiviral, and Antimicrobial Activity of 1,2,4-Triazole Thioglycoside Derivatives

Abstract

The reaction of 5-(2-methylthio)phenyl-1,2,4-triazole-3-thiol with glucosyl, galactosyl, lactosyl bromide, and peracetylated ribose under the conventional and microwave irradiation methods afforded the corresponding S-glycosides. Deacetylation of S-glycosides gave the corresponding deacetylated derivatives. Reaction of 5-(2-methylthio)phenyl-1,2,4-triazole-3-thiol with 4-acetoxybutyl bromide, 2-acetoxyethoxymethyl bromide, 3-chloropropanol, 1,3-dichloroopropan-2-ol, epichlorohydrin, allyl bromide, and propargayl bromide gave the corresponding S-acyclonucleosides, which were deacetylated to give the corresponding deacetylated compounds. All the newly synthesized compounds were characterized by the IR, ¹H, ¹³C NMR, and elemental analyses. Some of these compounds were screened for their antiviral and antimicrobial activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the related elements to view the free supplemental file.     

Three‐component,one‐pot synthesis of pyrimido[4,5‐b]‐quinoline and pyrido[2,3‐d]pyrimidine derivatives

Reaction of 6‐amino‐2‐methylthiouracil and 6‐amino‐1,3‐dimethyluracil with equimoler amounts of cyclic ketones or cyclic 1,3‐diketones and the appropriate aromatic aldehydes yielded regioselectivity a series of polycyclic pyrimido[4,5‐b]quinoline and pyrido[2,3‐d]pyrimidine derivatives in good yields.     

Microwave-assisted efficient synthesis of azlactone derivatives using TsCl/DMF under solvent-free conditions

A simple and efficient procedure for the synthesis of azlactones employing condensation reaction of aromatic aldehydes with hippuric acid has been developed by using the tosyl chloride (TsCl) and dimethylformamide (DMF) system as condensing agent in the absence of solvents under microwave irradiation. The present protocol is operationally simple and offers several advantages such as high yields, short reaction time, and simple workup.     

A novel uranyl membrane sensor with potentiometric anionic response

A novel potentiometric uranyl membrane sensor with a divalent anionic response is developed, characterized and used for determination of uranyl ion. The sensor incorporates triethylenetetramine (TETA) as an ionophore in poly(vinyl chloride) matrix membrane (PVC) plasticized with o-nitrophenyloctyl ether (o-NPOE). In strong sulphate test solutions, UO₂²⁺ ion forms a highly stable [UO₂(SO₄)₂]²⁻ anion, extractable in TETA as {(2TETAH)²⁺ [UO₂(SO₄)₂]²⁻} complex. Formation of the complex is confirmed and characterized by elemental analysis, mass spectrometry and infrared spectrometry. Sensor based on this system displays at pH 2.5-3.8 a linear response over the concentration range of 1.0 × 10⁻¹-3.5 × 10⁻⁵ mol l⁻¹ uranium with a near-Nernstian calibration slope of −26.5 ± 0.3 mV decade⁻¹. The lower limit of detection is ∼5 μg ml⁻¹, the lifetime is 12 weeks and negligible interferences are caused by most common cations. Validation of the assay method reveals excellent performance characteristics in terms of sensitivity, selectivity, fast response and potential stability. The sensor is used for the determination of 0.01-7.09 wt% uranium in naturally occurring and certified ore samples. The results show an average recovery of 97.6% and compare fairly well with data obtained using X-ray fluorescence technique.