Insight into the Interaction Mechanism of HSA with Aztreonam: A Multispectroscopic and Computational Approach

Aztreonam is a Gram-negative bacteria-targeting synthetic monobactam antibiotic. Human serum albumin (HSA) plays an important role in the transference of pharmaceuticals, hormones, and fatty acids, along with other compounds, determining their biodistribution and physiological fate. Using several biophysical and in silico approaches, we studied the interaction of aztreonam with HSA under physiological environments in this study. Results confirm the formation of HSA-aztreonam complex where aztreonam showed moderate affinity towards HSA. A static mode of quenching was confirmed from the steady state fluorescence data. FRET findings also showed that there was a significant feasibility of energy transfer between HSA and aztreonam. Site marker displacement experimental conclusion suggested the binding site of aztreonam was the sub-domain IB of HSA. Circular dichroic spectroscopic analysis suggested that aztreonam interaction decreases the α-helical content of HSA. Changes in microenvironment were studied through synchronous fluorescence data. According to molecular docking results, the HSA-aztreonam complex is mostly maintained by non-covalent forces, with a binding energy of 7.7 kcal mol−1. The presence of a hydrogen bond, van der Waal interaction, and pi-anion interaction in the binding process, as well as conformational changes in HSA after binding with aztreonam, are all confirmed by molecular dynamic simulation

Moricandia sinaica (Boiss.): A Potent Source of Hypoglycaemic and Antidiabetic Remedy

Here, we evaluated the antidiabetic and hypoglycaemic activities of Moricandia sinaica, a species of the Brassicaceae family, for the first time. The hypoglycaemic and antidiabetic activities of the M. sinaica shoot’s methanol extract (MOR-1), butanol fraction (MOR-2), and aqueous fraction (MOR-3) were examined against streptozotocin-induced diabetes model in albino Swiss mice. The mice were divided into eight groups (each group consisted of 6 mice). MOR-1 (100 and 200 mg/kg), MOR-2 (100 and 200 mg/kg), and MOR-3 (100 and 200 mg/kg) were administered to groups III, IV, V, VI, VII, and VIII, respectively, for 15 days (daily). The blood samples were haematologically and biochemically assessed at 0 days, 7 days, and 15 days. Mice in group I were kept untreated as control while group II was treated with glibenclamide as standard. Antidiabetic effects increased with MOR-1 and MOR-2 doses in a dose-dependent manner. MOR-2 treatment (200 mg/kg) yielded the best results (29.56% and 40.07% after 7 and 15 days, respectively) compared to the results obtained at zero days. MOR-2 (200 mg/kg) showed the greatest decline in glucose levels (27.67% and 41.13% after 7 and 15 days, respectively). The results concluded that M. sinaica exhibited potential hypoglycaemic activity

Chemical Composition, Antioxidants, Antibacterial, and Insecticidal Activities of <i>Origanum elongatum</i> (Bonnet) Emberger & Maire Aerial Part Essential Oil from Morocco

The aim of this research is to profile the chemical composition of the essential oil (EO) extracted from the aerial parts of Origanum elongatum (O. elongatum) and to evaluate its antioxidant, antibacterial and insecticidal activities on Ceratitis capitata adults. Gas chromatography coupled with mass spectrometry (GC/MS) revealed a total of 27 constituents in EO of O. elongatum, which accounted for 99.08% of its constituents. Carvacrol (57.32%) was a main component, followed by p-cymene (14.70%) and γ-terpinene (9.84%). The antioxidant activity of O. elongatum EO was investigated using DPPH (1,1-diphenyl-2-picrylhydrazyl), FRAP (Ferric reducing antioxidant power), and TCA (the total antioxidant capacity) methods. This EO exhibited a remarkable antiradical and reducing power against DPPH (IC50 = 2.855 ± 0.018μL/mL), FRAP (EC0.5 = 0.124 ± 0.013µL/mL) and TCA (IC50 = 14.099 ± 0.389 mg AAE/g of the EO). The antibacterial tests in vitro, using the disc and dilution methods, were carried out on nine pathogenic bacteria isolated from the hospital patients, such as Enterococcus faecalis, Serratia fonticola, Staphylococcus aureus, Acinétobacter baumannii, Klebsiella oxytoca, Klebsiella pneumoniae sensible, E.coli sensible, E.coli resistante, and Enterobacter aerogenes. The EO demonstrated a considerable antibacterial activity with minimum inhibitory concentrations (MIC) from 2 to 8 µL/mL against all strains except Staphylococcus aureus (MIC = 32 µL/mL). Regarding the insecticidal activity, the fumigation test indicated a high efficacy (100% mortality), and a lethal dose of LD50  =  17 ± 0.53 μL/L air was found after 24 h of exposureTherefore, O. elongatum EO could be utilized as a natural antioxidant, antibiotic and biopesticides