Volume 77, Issue 9-10

Some bacteria can withstand the existence of an antibiotic without undergoing any genetic changes. They are neither cysts nor spores and are one of the causes of disease recurrence, accounting for about 1% of the biofilm. There are numerous approaches to eradication and combating biofilm-forming organisms. Nanotechnology is one of them, and it has shown promising results against persister cells. In the review, we go over the persister cell and biofilm in extensive detail. This includes the biofilm formation cycle, antibiotic resistance, and treatment with various nanoparticles. Furthermore, the gene-level mechanism of persister cell formation and its therapeutic interventions with nanoparticles were discussed.

Prebiotics, gut microbiota-fermentable substances, delay the development of type I diabetes. In the present study, we investigated the effect of two prebiotics (galacto-oligosaccharides and xylo-oligosaccharides) on the antioxidant protection, lipid profile, and inflammatory activity of rats with streptozotocin-induced diabetes. The following markers were studied – malondialdehyde, 8-hydroxy-2′-deoxyguanosine, ferric reducing ability of plasma (FRAP), triacylglycerols, total cholesterol (TC), high-density lipoproteins, C-reactive protein (CRP), and interleukin-6. Diabetes was induced in male Wistar experimental rats by streptozotocin injection, while the non-diabetic controls were injected with saline. Afterward the oligosaccharides were administered orally to the experimental animals. The blood collected following the decapitation was analyzed by ELISA. A modified protocol was used only for measuring the FRAP values. The galacto-oligosaccharides and xylo-oligosaccharides lowered the malondialdehyde levels in the diabetic rats ( p  < 0.05). The galacto-oligosaccharides decreased the serum levels of 8-hydroxy-2′-deoxyguanosine ( p  = 0.01), while the xylo-oligosaccharides increased the FRAP ( p  < 0.05) in the experimental animals. None of the oligosaccharides affected triacylglycerol and interleukin-6 concentrations, but the galacto-oligosaccharides decreased the TC and CRP levels in the diabetic animals. Both oligosaccharides exert a beneficial effect on the antioxidant protection of the diabetic rats, but have a minor effect on their lipid and inflammatory profiles.

Phytochemical investigation of Diospyros mespiliformis leaves resulted in the isolation of new acylated flavone isoscutellarein 7- O -(4′′′- O -acetyl)- β -allopyranosyl(1′′′ → 2′′)- β -glucopyranoside ( 1 ), along with eight known flavonoid metabolites, luteolin 3′,4′,6,8-tetramethyl ether ( 2 ), luteolin 4′- O - β -neohesperidoside ( 3 ), luteolin 7- O - β -glucoside ( 4 ), luteolin ( 5 ), quercetin ( 6 ), quercetin 3- O - β -glucoside ( 7 ), quercetin 3- O - α -rhamnoside ( 8 ), and rutin ( 9 ). Their structures were identified by analysis of spectroscopic (UV, NMR, and MS) data, as well as by acid hydrolysis for the isolated glycosides. The antioxidant activity of D. mespiliformis metabolites was determined by the DPPH radical-scavenging assay. The new acylated flavone ( 1 ) and flavonol O -rhamnoside ( 8 ) displayed the highest antioxidant activities with IC 50 values 15.46 and 12.32 μg/mL, respectively, with respect to the antioxidant ascorbic acid (IC 50 value 10.62 μg/mL). In addition, the isolated flavonoids were evaluated against four human pathogenic bacteria where the methylated flavone ( 2 ) exhibited potent activity against Escherichia coli with inhibition zone 34 mm, and mild activity of flavonol O -rhamnoside ( 8 ) against Staphylococcus aureus with MIC value 9.77 μg/mL. According to the MBC/MIC ratio, the antibacterial activity of the isolated flavonoids was considered flavonoid 2 is bactericidal nature against S. aureus, and flavonoids 3 and 4 are bactericidal against E. coli.

Artemia urumiana is bisexual population of the Lake Urmia of Iran. Its biomass was freeze dried and using its lyophilized powder, hydro-alcoholic extract was prepared and utilized in gold nanoparticles (Au NPs) synthesis. Six different Au NPs fabrication methods namely: microwave heating, hydrothermal, ultraviolet (UV) irradiation, ultrasonication, common heating using conventional heating, and self-assembling were utilized for Au NPs synthesis using A. urumiana extract. Gas chromatography analysis indicated that the prepared extract were contained numerous fatty acid methyl esters such as Hexadecanoic acid methyl ester. Results indicated that the formed NPs using heater and stirrer, and UV irradiation had minimum particle size of 25 and 94 nm, respectively. However, as compared to the formed Au NPs using heater and stirrer technique, UV irradiation fabricated Au NPs with high zeta potential value of −32.5 mV and small polydispersity value of 0.310. Results also demonstrated that the synthesized Au NPs using heater and stirrers, and UV irradiation had highest antioxidant activities of 13.7 and 11.9%, and bactericidal effects against Escherichia coli and Staphylococcus aurous bacteria strains, as compared to other fabricated Au NPs using other methods. There were insignificant ( p  > 0.05) differences between these two attributes of the formed Au NPs.

The current investigation applies the dual approach containing quantum chemical and molecular docking techniques to explore the potential of benzothiadiazole (BTz) and its derivatives as efficient electronic and bioactive materials. The charge transport, electronic and optical properties of BTz derivatives are explored by quantum chemical techniques. The density functional theory (DFT) and time dependent DFT (TD-DFT) at B3LYP/6-31G** level of theory utilized to optimize BTz and newly designed ligands at the ground and first excited states, respectively. The heteroatoms substitution effects on different properties of 4,7-bis(4-methylthiophene-2yl) benzo[c] [1,2,5]thiadiazole ( BTz2T ) as initial compound are studied at molecular level. Additionally, we also study the possible inhibition potential of COVID-19 from benzothiadiazole (BTz) containing derivatives by implementing the grid based molecular docking methods. All the newly designed ligands docked with the main protease (M PRO :PDB ID 6LU7) protein of COVID-19 through molecular docking methods. The studied compounds showed strong binding affinities with the binding site of M PRO ranging from −6.9 to −7.4 kcal/mol. Furthermore, the pharmacokinetic properties of the ligands are also studied. The analysis of these results indicates that the studied ligands might be promising drug candidates as well as suitable for photovoltaic applications.

Commercial pickled cucumbers are produced in variety of salt concentrations including brines up to 15% sodium chloride due to the preventive nature of the salt towards microbial growth. Although it is deemed necessary for manufacturers to utilize high amounts of salts to prolong shelf life, the high content creates a burden for the growth of beneficial microorganisms including probiotics. In this study, the production of naturally fermented cucumbers and their microbial viability were tested with the help of an experimental design tool, Box-Behnken Design (BBD), to evaluate the optimal conditions for the production process and to maintain the highest viability of potential beneficial microorganisms during storage. Accordingly, the operational conditions including salt concentration (2, 5, or 8%), fermentation temperature (20, 25, or 30 °C), and brine filling (pretreatment) temperature (80, 85, or 90 °C) were optimized with a significant fit to a quadratic model (p < 0.05). The trends for sugar consumption and total acid production were monitored to demonstrate the correlation between the above-mentioned operational parameters for the fermentation process of pickled cucumbers with indigenous microorganisms. Overall, 5% salt content, 70 °C filling temperature and 25 °C fermentation medium was determined to maintain over 6 log cfu/mL viability. The results represent a valuable contribution to the pickle industry including a know-how of process parameters.

In this study, novel 4-(5-((2/3/4-substituted benzyl)thio)-4-(4-substituted phenyl)-4 H -1,2,4-triazol-3-yl)-2-(pyridin-3/4-yl)thiazoles were synthesized following a multi-step synthetic procedure. All the compounds were screened with a panel of gram positive/negative bacteria, yeasts, and molds for antimicrobial activity using the disc diffusion method. Then, the minimum inhibitor concentration (MIC) and the minimum bactericidal concentration (MBC) values of active compounds were determined against Micrococcus luteus , Bacillus cereus , Listeria monocytogenes , and Staphylococcus aureus using the broth microdilution technique. These compounds were also screened for their inhibitory activities against S. aureus DNA gyrase by supercoiling assay. Furthermore, the crystal structure of S. aureus DNA gyrase B ATPase was subjected to a docking experiment to identify the possible interactions between the most active ligand and the active site. Lastly, the in silico technique was performed to analyze and predict the drug-likeness, molecular and ADME properties of the synthesized molecules.