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The discovery of a significantly large anomalous Hall effect in the chiral antiferromagnetic system—Mn3Ge—indicates that the Weyl points are widely separated in phase space and positioned near the Fermi surface. In order to examine the effects of Fe substitution in Mn3Ge on the presence and location of the Weyl points, we synthesized (Mn1−αFeα)3Ge (α=0−0.30) compounds. The AHE was observed in compounds up to α = 0.22, but only within the temperature range where the magnetic structure remains the same as the Mn3Ge. Additionally, positive longitudinal magnetoconductance and planar Hall effect (PHE) were detected within the same temperature and doping range. These findings strongly suggest the existence of Weyl points in (Mn1−αFeα)3Ge (α=0−0.22) compounds. Further, we observed that with an increase in Fe doping fraction, there is a significant reduction in the magnitude of anomalous Hall conductivity, PHE, and positive longitudinal magnetoconductance, indicating that the Weyl points move further away from the Fermi surface. Consequently, it can be concluded that suitable dopants in the parent Weyl semimetals have the potential to tune the properties of Weyl points and the resulting anomalous electrical transport effects.

Biogenic synthesis of nanoparticles has received a tremendous attention from the past few decades. The significant progress in the field of nanotechnology has resulted in a cost-effective and eco-friendly process for nanoparticle synthesis. In the present study, the extracellular synthesis of gold nanoparticles was carried out using culture supernatant of Streptomyces griseoruber , actinomycetes isolated from the soil. Bioreduction of gold nanoparticles was confirmed by UV–visible spectrophotometer that showed the peak between 520 and 550 nm. The crystalline nature and mean size of the GNPs were confirmed using XRD. FTIR revealed the possible functional group that could be useful in immobilisation and stabilisation of GNPs. Size and distribution of the biosynthesized GNPs were analysed by HR-TEM that showed the formation of GNPs in the range of 5–50 nm. The synthesised GNPs showed good catalytic activity for the degradation of methylene blue. The study shows the rapid and eco-friendly synthesis of GNPs from Streptomyces griseoruber , and this is the first report on the catalytic activity of GNPs from actinomycetes so far.

Endophytic actinomycetes are well known for their diverse bioactive entities and considered as an important source for drug development research. We isolated and identified four potential endophytic Streptomyces species, i.e., Streptomyces misionensis MI22, Streptomyces roietensis MI24, Streptomyces glaucescens MI29, and Streptomyces sp. MI04 inhabiting Madhuca insignis by its characteristic morphological features and 16S rRNA gene sequence analysis. S. misionensis MI22 exhibits a broad spectrum of anti-microbial activity against methicillin-resistant Staphylococcus aureus (25.00 ± 1.00 mm) followed by Bacillus subtilis (23.66 ± 0.57 mm), Escherichia coli (22.00 ± 0.00 mm), and Candida albicans (18.00 ± 0.00 mm). Minimum inhibitory concentrations of the ethyl acetate fraction of S. misionensis MI22 against test pathogens were ranged from 25 to 100 [mu]g/mL. Indeed, strain MI22 also exhibited significant anti-proliferative activity against HeLa cell line with IC.sub.50 value 98 [mu]g/mL and showed no cytotoxicity effect to the normal human embryonic kidney cell line in the MTT assay. The anti-microbial metabolites from strain MI22 were detected at R.sub.f 0.55 as depicted by the inhibition zone on the intensive band in TLC-bioautography assay. The study indicates that, anti-microbial metabolites of these endophytic Streptomyces species, especially S. misionensis MI22 as a prolific source to discover novel bioactive metabolites to combat multidrug-resistant pathogens.

Quorum sensing or cell to cell communication which includes inter- and intra-cellular communication has been implicated in the production of virulence factor and formation of biofilm in food-borne pathogens. In the present study, the effect of quorum sensing signals on the biofilms of food-borne pathogens has been elucidated. N-butryl homoserine lactone and N-hexanoyl homoserine lactone belonging to acyl homoserine lactone (AHL) family of signaling molecules were investigated for their effect on the biofilm formation (attachment and exopolymeric substance production) in the food-borne pathogens Escherichia coli , Salmonella enterica serovar Typhimurium and Vibrio parahemolyticus . The signaling molecules at a concentration of 1 µM were capable of increasing biofilm formation in all the tested pathogens. There was an increase in the attachment of the bacterial cells and biomass as observed by microtiter plate assay and exopolymeric substances production in the biofilms in presence of the AHLs. Further, it needs to be elucidated if the effect of AHLS on the biofilms of E. coli and S. enterica serovar Typhimurium is SdiA dependent.

Enterobacter cloacae is normally considered to be an opportunistic human pathogen. Here, we report on the whole-genome sequence of an endophytic E. cloacae, strain “Ghats1”, isolated from leaves of the medicinal plant Coscinium fenestratum Gaertn. Functional analysis of the Ghats1 genome revealed an enrichment for genes involved in the uptake and exchange of nutrients, for chemotaxis and for plant colonization. Unexpectedly though, there were no ORFs belonging to the “virulence factors and antibiotic resistance”. Moreover, the presence of hydrolytic enzymes and motility functions reveals the characteristics of an endophyte lifestyle of a bacterium that can colonize and adapt to plant environment. These results provide a better understanding of an endophytic lifestyle through plant–microbe interaction, which can be further exploited as a biocontrol agent.

The development of eco-friendly approach for the preparation of monodispersed gold nanoparticles (GNPs) has received much attention for their easy application. Most of the current methods involve known protocols which employ toxic chemicals and hazardous byproducts. This greatly limits their use in biomedical fields, particularly in clinical applications. Recent research has been focused on green synthesis methods to produce different nanoparticles with suitable commercial viability. The biosynthesis of monodispersed GNPs using the spent cultures of Klebsiella pneumoniae as reducing and stabilizing agent has been reported. The gold salt concentration to improve monodispersity and stability of GNPs has been optimized. Synthesized GNPs were characterized by UV–Visible spectroscopy showed absorption spectra in the range of 530–560 nm at different concentrations of HAuCl 4 . At the optimum reaction concentration of 1.5 mM HAuCl 4 , absorption peak was obtained at 535 nm. The GNPs have been further characterized by X-ray diffraction, FTIR, DLS and TEM analysis. The DLS graph showed that the particles were more monodispersed. The TEM image showed the formation of spherical shaped GNPs in the range of 4–10 nm. The effect of gold salt concentration on dispersity, size and stability of the biosynthesized GNPs has been reported.

Mineral Trioxide Aggregate (MTA) has been a material of revolution in the field of dentistry since its introduction in the 1990s. It is being extensively used for perforation repairs, apexification, root-end filling, obturation, tooth fracture repair, regenerative procedures, apexogenesis, pulpotomies, and as a pulp-capping material because of its desired features such as biocompatibility, bioactivity, hydrophilicity, sealing ability, and low solubility. Even though its application is wide, it has its own drawbacks that prevent it from reaching its full potential as a comprehensive replacement material, including a long setting time, discoloration, mud-like consistency, and poor handling characteristics. MTA is a material of research interest currently, and many ongoing studies are still in process. In this review, the newer advancements of this versatile material by modification of its physical, chemical, and biological properties, such as change in its setting time, addressing the discoloration issue, inclusion of antimicrobial property, improved strength, regenerative ability, and biocompatibility will be discussed. Hence, it is important to have knowledge of the traditional and newer advancements of MTA to fulfill the shortcomings associated with the material.

In this study, we fabricated Li + doped Bi 1/2 Na 1/2- x Li x TiO 3 [BNLT] ( x  = 0.0, 0.025, 0.05, 0.075 and 0.1) nanoceramics by double sintered solid-state reaction method. The structural, optical, dielectric and ferroelectric properties of the ceramic samples have been investigated. X-ray diffraction results confirm that all the ceramics are pure phase perovskite with rhombohedral structure and R 3 c space group. The different bonds (Bi 3+ /Na + /Li + and Ti 4+ –O) related to vibrational modes have been studied by analyzing the Raman spectra. The observed optical band gaps were found to decrease from 3.37 to 3.31 eV as the Li + doping is increased. The dielectric permittivity ( ε′ ) and loss factor (tan δ ) reduces with a raise in the frequency whereas at elevated frequency both became constant. Dielectric plot show irregular trends with increasing Li + ion replacement. The ac conductivity is found to rise with a higher frequency. Modulus and complex impedance study point toward the continuation of equal grain and grain boundary assistance in BNLT ceramics. The P – E hysteresis loops verify the ferroelectric nature of all the ceramics.

In search of novel antidiabetic agents, we synthesized a new series of chalcones with benzimidazole scaffolds by an efficient ‘one-pot’ nitro reductive cyclization method and evaluated their α-glucosidase and α-amylase inhibition studies. The ‘one-pot’ nitro reductive cyclization method offered a simple route for the preparation of benzimidazoles with excellent yield and higher purity compared to the other conventional acid- or base-catalyzed cyclization methods. 1H, 13C NMR, IR, and mass spectrum data were used to characterize the compounds. Single-crystal XRD data confirmed the 3D structure of compound 7c, which was crystalized in the P1¯ space group of the triclinic crystal system. Hirshfeld surface analysis validates the presence of O-H..O, O-H…N, and C-H…O intermolecular hydrogen bonds. From the DFT calculations, the energy gap between the frontier molecular orbitals in 7c was found to be 3.791 eV. From the series, compound 7l emerged as a potent antidiabetic agent with IC50 = 22.45 ± 0.36 µg/mL and 20.47 ± 0.60 µg/mL against α-glucosidase and α-amylase enzymes, respectively. The in silico molecular docking studies revealed that compound 7l has strong binding interactions with α-glucosidase and α-amylase proteins. Molecular dynamics studies also revealed the stability of compound 7l with α-glucosidase and α-amylase proteins.

Cu ion–doped Zn0.94Cd0.06−xCuxO (x = 3 and 5 wt%) nanomaterials are prepared via low temperature sol–gel auto-combustion method using citric acid (C6H8O7) as a fuel radical. Tailoring effects of Cu doping concentration on the optical and dielectric relaxation properties of Zn0.94Cd0.06O nanomaterials are investigated using XRD technique, UV–Vis diffuse reflectance, and impedance spectroscopy. XRD analysis reveals that all the prepared nanomaterials are crystallized in wurtzite hexagonal structure with space group P63mc. Rietveld refinement also confirms the single-phase crystalline nature. The average diameters of the synthesized nanomaterials estimated by Debye–Scherrer formula are found as ~ 29.50 nm (Zn0.94Cd0.03Cu0.03O) and 30.21 nm (Zn0.94Cd0.01Cu0.05O) after calcination at 600 °C. Direct band gap increases from 3.04 eV (3 wt% Cu) to 3.10 eV (5 wt% Cu) with increasing Cu concentration. Dielectric behavior is governed by the space charge polarization whereas the electric modulus studies support non-Debye [β < 1 (0.83 at 3 wt% Cu and 0.88 at 5 wt% Cu)] type of dielectric relaxation. The Nyquist plot of 3 wt% Cu ion doping shows small semicircle, which is associated with non-ohmic nature. Sizes of the semicircles are correlated with the grain resistance that points out the electrode nature of prepared nanomaterials. Finally, 3 wt% Cu ion–doped nanomaterials show high value of dielectric constant (~ 1150 at 20 Hz) and minimum loss (~ 1.96 at 20 Hz) that may be suitable for potential application in semiconductor devices.