Bacteria populating freshly appeared supraglacial lake possess metals and antibiotic-resistant genes.

Antibiotic resistance (AR) has been extensively studied in natural habitats and clinical applications. AR is mainly reported with the use and misuse of antibiotics; however, little is known about its presence in antibiotic-free remote supraglacial lake environments. This study evaluated bacterial strains isolated from supraglacial lake debris and meltwater in Dook Pal Glacier, northern Pakistan, for antibiotic-resistant genes (ARGs) and metal-tolerant genes (MTGs) using conventional PCR. Several distinct ARGs were reported in the bacterial strains isolated from lake debris (92.5%) and meltwater (100%). In lake debris, 57.5% of isolates harbored the blaTEM gene, whereas 58.3% of isolates in meltwater possessed blaTEM and qnrA each. Among the ARGs, qnrA was dominant in debris isolates (19%), whereas in meltwater isolates, qnrA (15.2%) and blaTEM (15.2%) were dominant. ARGs were widely distributed among the bacterial isolates and different bacteria shared similar types of ARGs. Relatively greater number of ARGs were reported in Gram-negative bacterial strains. In addition, 92.5% of bacterial isolates from lake debris and 83.3% of isolates from meltwater harbored MTGs. Gene copA was dominant in meltwater isolates (50%), whereas czcA was greater in debris bacterial isolates (45%). Among the MTGs, czcA (18.75%) was dominant in debris strains, whereas copA (26.0%) was greater in meltwater isolates. This presents the co-occurrence and co-selection of MTGs and ARGs in a freshly appeared supraglacial lake. The same ARGs and MTGs were present in different bacteria, exhibiting horizontal gene transfer (HGT). Both positive and negative correlations were determined between ARGs and MTGs. The research provides insights into the existence of MTGs and ARGs in bacterial strains isolated from remote supraglacial lake environments, signifying the need for a more detailed study of bacteria harboring ARGs and MTGs in supraglacial lakes.

Temperature-dependent transformation of microbial community: A systematic approach to analyzing functional microbes and biogas production.

The stability and effectiveness of the anaerobic digestion (AD) system are significantly influenced by temperature. While majority research has focused on the composition of the microbial community in the AD process, the relationships between functional gene profile deduced from gene expression at different temperatures have received less attention. The current study investigates the AD process of potato peel waste and explores the association between biogas production and microbial gene expression at 15, 25, and 35 °C through metatranscriptomic analysis. The production of total biogas decreased with temperature at 15 °C (19.94 mL/g VS), however, it increased at 35 °C (269.50 mL/g VS). The relative abundance of Petrimonas, Clostridium, Aminobacterium, Methanobacterium, Methanothrix, and Methanosarcina were most dominant in the AD system at different temperatures. At the functional pathways level 3, α-diversity indices, including Evenness (Y = 5.85x + 8.85; R2 = 0.56), Simpson (Y = 2.20x + 2.09; R2 = 0.33), and Shannon index (Y = 1.11x + 4.64; R2 = 0.59), revealed a linear and negative correlation with biogas production. Based on KEGG level 3, several dominant functional pathways associated with Oxidative phosphorylation (ko00190) (25.09, 24.25, 24.04%), methane metabolism (ko00680) (30.58, 32.13, and 32.89%), and Carbon fixation pathways in prokaryotes (ko00720) (27.07, 26.47, and 26.29%), were identified at 15 °C, 25 °C and 35 °C. The regulation of biogas production by temperature possibly occurs through enhancement of central function pathways while decreasing the diversity of functional pathways. Therefore, the methanogenesis and associated processes received the majority of cellular resources and activities, thereby improving the effectiveness of substrate conversion to biogas. The findings of this study illustrated the crucial role of central function pathways in the effective functioning of these systems.

Evaluating the relative influence of climate and human activities on recent vegetation dynamics in West Bengal, India.

Assessing the relative importance of climate change and human activities is important in developing sustainable management policies for regional land use. In this study, multiple remote sensing datasets, i.e. CHIRPS (Climate Hazard Group InfraRed Precipitation with Station Data) precipitation, MODIS Land Surface Temperature (LST), Enhanced Vegetation Index (EVI), Potential Evapotranspiration (PET), Soil Moisture (SM), WorldPop, and nighttime light have been analyzed to investigate the effect that climate change (CC) and regional human activities (HA) have on vegetation dynamics in eastern India for the period 2000 to 2022. The relative influence of climate and anthropogenic factors is evaluated on the basis of non-parametric statistics i.e., Mann-Kendall and Sen's slope estimator. Significant spatial and elevation-dependent variations in precipitation and LST are evident. Areas at higher elevations exhibit increased mean annual temperatures (0.22 °C/year, p < 0.05) and reduced winter precipitation over the last two decades, while the northern and southwest parts of West Bengal witnessed increased mean annual precipitation (17.3 mm/year, p < 0.05) and a slight cooling trend. Temperature and precipitation trends are shown to collectively impact EVI distribution. While there is a negative spatial correlation between LST and EVI, the relationship between precipitation and EVI is positive and stronger (R2 = 0.83, p < 0.05). Associated hydroclimatic parameters are potent drivers of EVI, whereby PET in the southwestern regions leads to markedly lower SM. The relative importance of CC and HA on EVI also varies spatially. Near the major conurbation of Kolkata, and confirmed by nighttime light and population density data, changes in vegetation cover are very clearly dominated by HA (87%). In contrast, CC emerges as the dominant driver of EVI (70-85%) in the higher elevation northern regions of the state but also in the southeast. Our findings inform policy regarding the future sustainability of vulnerable socio-hydroclimatic systems across the entire state.

Novel yellowish-green single-phased spinel Mg1-xBaxAl2O4:Mn2+ phosphor(s) for color rendering white-light-emitting diodes.

For white light-rendering research activities, interpretation by using colored emitting materials is an alternative approach. But there are issues in designing the white color emitting materials. Particularly, differences in thermal and decay properties of discrete red, green, and blue emitting materials led to the quest for the search of a single-phased material, able to emit primary colors for white light generation. The current study is an effort to design a simple, single-phase, and cost-effective material with the tunable emission of primary colors by a series of Mg1-xBaxAl2O4:Mn2+ nanopowders. Doping of manganese ion (Mn2+) in the presence of the larger barium cation (Ba2+) at tetrahedral-sites of the spinel magnesium aluminate (MgAl2O4) structure led to the creation of antisite defects. Doped samples were found to have lower bandgaps compared with MgAl2O4, and hybridization of 3d-orbitals of Mn2+ with O(2p), Mg(2s)/Al(2s3p) was found to be responsible for narrowing the bandgap. The distribution of cations at various sites at random results in a variety of electronic transitions between the valance band and oxygen vacancies as well as electron traps produced the antisite defects. The suggested compositions might be used in white light applications since they have three emission bands with centers at 516 nm (green), 464 nm (blue) and 622 nm (red) at an excitation wavelength of 380 nm. A detailed discussion to analyze the effects of the larger cationic radius of Ba2+ on the lattice strain, unit cell parameters, and cell volumes using X-ray diffraction analysis is presented.

Green synthesis of tellurium-doped SnO2 nanoparticles with sulfurized g-C3 N4 : Insights into methylene blue photodegradation and antibacterial capability.

The construction of SnO2 nanoparticles (NPs), specifically Te-doped SnO2 NPs, using a simple and economical co-precipitation technique has been thoroughly described in this work. NH3 served as the reducing agent in this procedure, whilst polyethylene glycol served as the capping agent. The primary goals of our work were to investigate the physicochemical properties of the synthesized SnO2 NPs and assess their potential use as antibacterial agents and photocatalysts. Scanning electron microscopy-energy dispersive X-ray, ultraviolet light, Fourier transform infrared spectroscopy, X-ray diffraction (XRD), and other analytical techniques were used to thoroughly analyze the NPs. Based on the full width at half maximum of the most noticeable peaks in the XRD spectrum, the Debye-Scherrer equation was used to calculate the crystallite sizes, which indicated the presence of a single tetragonal SnO2 phase. Particularly noteworthy was the exceptional photocatalytic activity of graphene-assisted Te-doped SnO2 NPs, achieving an impressive decomposition efficiency of up to 98% in the photo-oxidation of methylene blue. Furthermore, our investigation delved into the antibacterial attributes of the synthesized SnO2 NPs against Escherichia coli and Staphylococcus aureus, demonstrating inhibitory effects on both bacteria strains. This suggests potential applications for these NPs in various environmental and medical contexts.

Harnessing solar power for enhanced photocatalytic degradation of coloured pollutants using novel Mg-doped-ZnFe2O4/S@g-C3N4 heterojunction: A facile hydrothermal synthesis approach.

The ability of heterogeneous photocatalysis to effectively remove organic pollutants from wastewater has shown great promise as a tool for environmental remediation. Pure zinc ferrites (ZnFe2O4) and magnesium-doped zinc ferrites (Mg@ZnFe2O4) with variable percentages of Mg (0.5, 1, 3, 5, 7, and 9 mol%) were synthesized via hydrothermal route and their photocatalytic activity was checked against methylene blue (MB) taken as a model dye. FTIR, XPS, BET, PL, XRD, TEM, and UV-Vis spectroscopy were used for the identification and morphological characterization of the prepared nanoparticles (NPs) and nanocomposites (NCs). The 7% Mg@ZnFe2O4 NPs demonstrated excellent degradation against MB under sunlight. The 7% Mg@ZnFe2O4 NPs were integrated with diverse contents (10, 50, 30, and 70 wt.%) of S@g-C3N4 to develop NCs with better activity. When the NCs were tested to degrade MB dye, it was revealed that the 7%Mg@ZnFe2O4/S@g-C3N4 NCs were more effective at utilizing solar energy than the other NPs and NCs. The synergistic effect of the interface formed between Mg@ZnFe2O4 and S@g-C3N4 was primarily responsible for the boosted photocatalytic capability of the NCs. The fabricated NCs may function as an effective new photocatalyst to remove organic dyes from wastewater.

Comparative investigation of tellurium-doped transition metal nanoparticles (Zn, Sn, Mn): Unveiling their superior photocatalytic and antibacterial activity.

In this study, tellurium-doped and undoped metal oxide nanoparticles (NPs) (ZnO, Mn3O4, SnO2) are compared, and a practical method for their synthesis is presented. Nanocomposites were created using the coprecipitation process, and comparisons between the three material categories under study were made using a range of characterization methods. The produced materials were subjected to structural, morphological, elemental composition, and functional group analyses using XRD, FESEM in combination with EDS, and FTIR. The optical characteristics in terms of cutoff wavelength were evaluated using UV-visible spectroscopy. Catalyzing the breakdown of methylene blue (MB) dye, the isolated nanocomposites demonstrated very consistent behavior when utilized as catalysts. Regarding both doped and undoped ZnO NPs, the maximum percentage of degradation was found to be 98% when exposed to solar Escherichia coli and Staphylococcus aureus, which stand for gram-positive and gram-negative bacteria, respectively, and were chosen as model strains for both groups using the disk diffusion technique in the context of in vitro antibacterial testing. Doped and undoped ZnO NPs exhibited greater antibacterial efficacy, with significant inhibition zones measuring 31.5 and 37.8 mm, compared with other metal oxide NPs.

A novel UV-resistant bacterium Sphingomonas endolithica sp. nov., and genomic analysis, isolated from the north slope of Mount Everest.

Gram-stain-negative, aerobic, rod-shaped, non-motile bacterium strain ZFBP2030T was isolated from a rock on the North slope of Mount Everest. This strain contained a unique ubiquinone-10 (Q-10) as a predominant respiratory quinone. Among the tested fatty acids, the strain contained summed feature 8, C14:0 2OH, and C16:0, as major cellular fatty acids. The polar lipid profile contained phosphatidyl glycerol, phosphatidyl ethanolamine, three unidentified phospholipids, two unidentified aminolipids, and six unidentified lipids. The cell-wall peptidoglycan was a meso-diaminopimelic acid, and cell-wall sugars were ribose and galactose. Phylogenetic analyses based on 16S rRNA gene sequence revealed that strain ZFBP2030T was a member of the genus Sphingomonas, exhibiting high sequence similarity to the 16S rRNA gene sequences of Sphingomonas aliaeris DH-S5T (97.9%), Sphingomonas alpina DSM 22537T (97.3%) and Sphingomonas hylomeconis CCTCC AB 2013304T (97.0%). The 16S rRNA gene sequence similarity between ZFBP2030T and other typical strains was less than 97.0%. The average amino acid identity values, average nucleotide identity, and digital DNA-DNA hybridization values between strain ZFBP2030T and its highest sequence similarity strains were 56.9-79.9%, 65.1-82.2%, and 19.3-25.8%, respectively. The whole-genome size of the novel strain ZFBP2030T was 4.1 Mbp, annotated with 3838 protein-coding genes and 54 RNA genes. Moreover, DNA G + C content was 64.7 mol%. Stress-related functions predicted in the subsystem classification of the strain ZFBP2030T genome included osmotic, oxidative, cold/heat shock, detoxification, and periplasmic stress responses. The overall results of this study clearly showed that strain ZFBP2030T is a novel species of the genus Sphingomonas, for which the name Sphingomonas endolithica sp. nov. is proposed. The type of strain is ZFBP2030T (= EE 013T = GDMCC 1.3123T = JCM 35386T).

Development and Validation of Novel HPLC Methods for Quantitative Determination of Vitamin D3 in Tablet Dosage Form.

In the present work, an efficient isocratic HPLC method was developed for the precise and accurate estimation of vitamin D3 in tablet form. The chromatographic conditions comprised an L3 silica column (5 µm in particle size, 4.6 mm × 250 mm) with a mobile phase n-hexane/ethyl acetate (85:15 v/v) with a flow rate of 2.0 mL/min and a detection wavelength of 292 nm. The new methodology was validated for accuracy, precision, specificity, robustness, and quantification limits according to an official monograph of USP/BP and ICH guidelines. The peak areas of the six replicates of the homogeneous sample were recorded. The mean value obtained was 67,301, and the relative standard deviation (RSD) was 0.1741. The linearity and range were in the acceptable bounds, i.e., 0.999, which was calculated using regression line analysis. The results show that the method is truly acceptable as the RSD, as the flow rate was 0.81%, while for the mobile phase composition, it was 0.72%, which lies in the acceptable range. The limit of detection (LOD) and the limit of quantification (LOQ) values were 0.0539 µg/mL and 0.1633 µg/mL, respectively. The % RSD of the intra and inter-day precision of the method was deemed acceptable according to the international commission for harmonization guidelines. The developed method has potential to be used for the detection and quantification of vitamin D3 during routine analysis for tablets in dosage form.

Development of stable S-scheme 2D-2D g-C3N4/CdS nanoheterojunction arrays for enhanced visible light photomineralisation of nitrophenol priority water pollutants.

The investigation focused on creating and studying a new 2D-2D S-scheme CdS/g-C3N4 heterojunction photocatalyst. Various techniques examined its structure, composition, and optical properties. This included XRD, XPS, EDS, SEM, TEM, HRTEM, DRS, and PL. The heterojunction showed a reduced charge recombination rate and more excellent stability, helping to lessen photocorrosion. This was due to photogenerated holes moving more quickly out of the CdS valence band. The interface between g-C3N4 and CdS favored a synergistic charge transfer. A suitable flat band potential measurement supported enhanced reactive oxygen species (ROS) generation in degrading 4-nitrophenol and 2-nitrophenol. This resulted in remarkable degradation efficiency of up to 99% and mineralization of up to 79%. The findings highlighted the practical design of the new 2D-2D S-scheme CdS/g-C3N4 heterojunction photocatalyst and its potential application in various energy and environmental settings, such as pollutant removal, hydrogen production, and CO2 conversion.

Temperature drives microbial communities in anaerobic digestion during biogas production from food waste.

Resource depletion and climate changes due to human activities and excessive burning of fossil fuels are the driving forces to explore alternatives clean energy resources. The objective of this study was to investigate the potential of potato peel waste (PPW) at various temperatures T15 (15 °C), T25 (25 °C), and T35 (35 °C) in anaerobic digestion (AD) for biogas generation. The highest biogas and CH4 production (117 mL VS-g and 74 mL VS-g) was observed by applying 35 °C (T35) as compared with T25 (65 mL VS-g and 22 mL VS-g) on day 6. Changes in microbial diversity associated with different temperatures were also explored. The Shannon index of bacterial community was not significantly affected, while there was a positive correlation of archaeal community with the applied temperatures. The bacterial phyla Firmicutes were strongly affected by T35 (39%), whereas Lactobacillus was the dominant genera at T15 (27%). Methanobacterium and Methanosarcina, as archaeal genera, dominated in T35 temperature reactors. In brief, at T35, Proteiniphilum and Methanosarcina were positively correlated with volatile fatty acids (VFAs) concentration. Spearman correlation revealed dynamic interspecies interactions among bacterial and archaeal genera; facilitating the AD system. This study revealed that temperature variations can enhance the microbial community of the AD system, leading to increased biogas production. It is recommended for optimizing the AD of food wastes.

In Silico Analysis of Calotropis procera-Derived Phytochemicals Targeting 3CL Proteoase of SARS-CoV-2.

The coronavirus known as SARS-CoV-2 has enveloped virions with single-stranded positive-sense RNA genome. It infects mammals, including humans, via the respiratory tract. The non-structural protein of coronavirus, main protease (3CLp) is a key enzyme in the disease's progression. This study aimed to screen phytochemicals derived from Calotropis Procera as potential drugs against 3CLp. Through database search, 50 phytochemicals were identified in the Calotropis sp. To evaluate the possible drug-like properties of these phytochemicals, the studies like, ADMET (Absorption, Distribution, Metabolism, Excretion, Toxicity) analysis, molecular docking and density functional theory (DFT) were performed. Furthermore, GC-MS was performed using water and ethanolic extracts from the plant leaves. The ADMET analysis and docking results showed 11 phytochemicals as probable drug candidates against 3CLp of SARS-CoV-2. All these phytochemicals showed ≥ - 4.3 kcal/mol binding affinity, similar to previously reported inhibitors. Furthermore, based on band energy gap, EHOMO, ELUMO, and DFT analyses, it was shown that these phytochemicals had a significant level of reactivity necessary for the interaction. Among all, the phytochemicals uscharin, voruscharin, frugoside, coroglaucigenin, and benzoylisolineolone may be considered the top 5 drug-like candidates against 3CLp. Furthermore, the selected phytochemicals may be employed for in vitro and in vivo studies for the advancement of a probable drug alongside SARS-CoV-2.

Tailoring of an anti-diabetic drug empagliflozin onto zinc oxide nanoparticles: characterization and in vitro evaluation of anti-hyperglycemic potential.

Diabetes is a serious health issue that can be a great risk factor related to numerous physical problems. A class of drugs "Gliflozin" especially Sodium Glucose Co. Transporter 2 was inhibited by a novel drug, which is known as "empagliflozin". While ZnO nanoparticles (NPs) had considerable promise for combating diabetes, it was employed in the treatment and management of type-2 diabetes mellitus. The new drug empagliflozin was initially incorporated into Zinc Oxide NPs in this study using the surface physio-sorption technique, and the degree of drug adsorption was assessed using the HPLC method. The tailored product was characterized by using the FTIR, EDX, Ultraviolet-Visible, XRD and SEM techniques. With an average particle size of 17 nm, SEM revealed mono-dispersion of NPs and sphere-like form. The Freundlich isotherm model best fits and explains the data for the physio-sorption investigation, which examined adsorption capabilities using adsorption isotherms. The enzymes α-amylase and α-glucosidase, which are involved in the human metabolism of carbohydrates, were used in the in-vitro anti-diabetic assays. It was discovered that the composite showed the highest levels of 81.72 and 92.77% inhibition of -α-amylase and -glucosidase at an absolute concentration of 1000 µg per ml with IC50 values of 30.6 µg per ml and 72 µg per ml.

Evaluation of a novel composite of expanded polystyrene with rGO and SEBS-g-MA.

This study displays the effect of reduced graphene oxide (rGO) nanofiller and polystyrene-b-poly(ethylene-ran-butylene)-b-polystyrene-grafted maleic anhydride (SEBS-g-MA) on the optical, thermal, and mechanical features of expanded polystyrene (EPS). First, the thin films of pristine EPS and composites were prepared using solution cast method. The prepared films were subjected to fourier-transform infrared (FTIR), SEM, UV-visible spectrophotometer, thermogravimetric analysis/differential scanning calorimetry, and universal testing machine for structural, morphological, optical, thermal, and mechanical characterizations. Optical study revealed a significant increase in refractive index and absorption of composites than EPS. Indirect band-gap energy of EPS (~4.08 eV) was reduced to ~1.61 eV for rGO composite and ~ 2.23 eV for composite composed of rGO and SEBS-g-MA. Thermal analyses presented improvement in characterization temperatures such as T10, T50, Tp, Tm, and Tg of composites, which ultimately lead to the thermal stability of prepared composites than pristine EPS. Stress-strain curves displayed higher yield strength (46.62 MPa), Young's modulus (96.29 MPa), and strain at break (0.54%) for EPS+rGO composite than pure EPS having stress at break (1.01 MPa), Young's modulus (12.44 MPa), and strain at break (0.08%). Moreover, ductility with relatively higher strain at break (0.61%) and lower Young's modulus (79.32 MPa) and yield strength (32.98 MPa) was noticed in EPS+rGO+SEBS-g-MA composite than EPS+rGO composite film. Morphological analysis revealed a change in globular morphology of EPS and inhomogeneous dispersion of rGO in EPS to homogeneously dispersed rGO in EPS matrix without globules owing to the addition of SEBS-g-MA. The increase in compatibility of EPS and rGO due to SEBS-g-MA was also observed in FTIR spectra. RESEARCH HIGHLIGHTS: Here, the solution casting approach was used to create the composite film of EPS and rGO with globules of various sizes. After adding SEBS-g-MA, the shape altered to globular free films exhibiting homogenous dispersion of rGO in EPS matrix. An optical investigation showed that composite materials had a significantly higher refractive index and absorption than EPS. The optical, thermal, and mechanical investigations suggest that the produced composites may be a great substitute for virgin EPS, allowing for a wider range of applications.