Rekha Kumari

Lack of regular monitoring of water sources may lead to undetected contamination, posing serious health risks and necessitating regular water quality assessments. Sampling for physicochemical, microbial analyses, and online surveys across three higher education institutions was done to evaluate water quality. Spatiotemporal variations among physicochemical parameters showed that the pH, EC, and TDS decreased during the wet season, reflecting the dilution effect of rain. However, DO increased from 0.67 to 4.83 ppm, indicating better aeration. PCA showed seasonal variability, whereas the correlation matrix highlighted both positive and negative interrelationships between temperature-pH (− 0.25), DO-ORP (0.11), and TDS-EC (1.00). Potentially toxic metals were either negligible or not detected. Metagenomics revealed the presence of 29 bacterial phyla, 61 classes, 124 orders, 241 families, and 457 genera. Canonical correspondence analysis showed the influence of Mo, EC, salinity, and TDS on Bacteroidota, Chloroflexota, Cyanobacteriota, and Planctomycetota, whereas Verrucomicrobiota, Acidobacteriota, Chlamydiota, Candidatus Melainabacteria, Bdellovibrionota, and Deinococcota were affected by Ni, pH, and COD. Pathogen mapping revealed the presence of Vibrio, Pseudomonas, Enterobacter spp., etc., responsible for diseases such as cholera, diarrhea, and typhoid. Also, occupants’ perception about the water quality emphasizes the need for better management of drinking water in HEIs.

The gut bacterial strains and their metabolites have been shown to play a significant role in obesity, but the molecular mechanisms underlying this association are largely unresolved. Obesity is a multifactorial problem and is controlled by various mechanisms and pathways to produce and store fat cells. Bacteriocins are secondary metabolites produced by gut bacteria to defend themselves against their competitors. Recently, they have gained great attention due to their role in metabolic disorders, including obesity. Stearoyl-CoA desaturase 1 (SCD1) is a key enzyme involved in the differentiation of adipocytes. The aim of this study is to show the regulation of SCD1 by bacteriocins and thus their importance in obesity control. We screened the human gut bacteriome for the presence of bacteriocins, predicted their structures, and showed their inhibitory role by molecular docking with SCD1. Further, to confirm the docking results, MDS of six top scoring SCD1-bacteriocin complexes were carried out for 100 ns. These six bacteriocins namely, Plantaricin S-beta, Carnolysin, Lactococcin B, Bacteriocin Iic, Plantaricin N, and Thermophilin A, with strong binding affinities, are primarily produced by bacterial strains from the Lactobacillaeacea family. These findings can be the basis of further experiments for enhanced understanding of the underlying mechanisms for obesity control, specifically bacteriocins driven regulation of the SCD1 enzyme. In addition, a consortium of bacterial strains producing these bacteriocins can be developed and used as probiotics for the amelioration of obesity and other metabolic complications. Communicated by Ramaswamy H. Sarma

Titanium dioxide nanoparticles (TiO₂NPs) usage is increasing in everyday consumer products, hence, assessing their toxic impacts on living organisms and environment is essential. Various studies have revealed the significant role of TiO₂NPs physicochemical properties on their toxicity. However, TiO₂NPs are still poorly characterized with respect to their physicochemical properties, and environmental factors influencing their toxicity are either ignored or are too complex to be assessed under laboratory conditions. The outcomes of these studies are diverse and inconsistent due to lack of standard protocols. TiO₂NPs toxicity also differs for in vivo and in vitro systems, which must also be considered during standardization of protocols to maintain uniformity and reproducibility of results. This review critically evaluates impact of different physicochemical parameters of TiO₂NPs and other experimental conditions, employed in different laboratories in determining their toxicity towards bacteria. These important observations may be helpful in evaluation of environmental risks posed by these nanoparticles and this can further assist regulatory bodies in policymaking.