Compatibility of pulse protein in the formulation of plant based yogurt: a review of nutri-functional properties and processing impact.

With the increased environmental concerns and health awareness among consumers, there has been a notable interest in plant-based dairy alternatives. The plant-based yogurt market has experienced rapid expansion in recent years. Due to challenges related to cultivation, higher cost of production and lower protein content researchers have explored the viability of pulse-based yogurt which has arisen as an economically and nutritionally abundant solution. This review aims to examine the feasibility of utilizing pulse protein for yogurt production. The nutritional, antinutritional, and functional characteristics of various pulses were discussed in detail, alongside the modifications in these properties during the various stages of yogurt manufacturing. The review also sheds light on pivotal findings from existing literature and outlines challenges associated with the production of pulse-based yogurt. Pulses have emerged as promising base materials for yogurt manufacturing due to their favorable nutritional and functional characteristics. Further, the fermentation process can effectively reduce antinutritional components and enhance digestibility. Nonetheless, variations in sensorial and rheological properties were noted when different types of pulses were employed. This issue can be addressed by employing suitable combinations to achieve the desired properties in pulse-based yogurt.

Safety Assessment of Ultra High Dilutions of Camphora officinarum: A Preclinical Investigation.

Background: Camphora officinarum (CO) is a commonly used homeopathic remedy for treating colds, collapse, and recurrent eruptive illnesses. Objective: Due to the non-availability of safety data on CO, the current study intended to determine the oral toxicity of CO in its ethanol-potentized dilutions 6C, 30C, and 200C in Wistar albino rats as per OECD guidelines. Materials and methods: A single oral dose of CO-6C, 30C, and 200C (2000 µl/kg) was administered, and the animals were monitored for behavior and mortality for up to 14 days in an acute toxicity study. In the subacute study, the effects of daily oral administration of CO-6C, 30C, and 200C (200 µl/kg) for 28 days were observed for clinical signs, change in body weight, and mortality. Hematological, biochemical, and histopathological analyses were assessed and organ weights were determined. Results: Results indicate no mortality of CO in its potencies in the acute toxicity study and was found to be safe at 2000 µl/kg dosage in the subacute toxicity study. CO (200 µl/kg/day) did not show any signs of toxicity in the hematological, biochemical, and histopathological analyses, along with organ weights. Conclusion: In conclusion, the findings suggest that CO in potencies of 6C, 30C, and 200C is safe up to a single oral dose of 2000 µl/kg body weight, and the No Observed Adverse Effect Level (NOAEL) was determined to be greater than 200 µl/kg/day.

Statistical Modelling of Thermostable Cellulase Production Conditions of Thermophilic Geobacillus sp. TP-1 Isolated from Tapovan Hot Springs of the Garhwal Himalayan Mountain Ranges, India.

A thermo-alkali stable cellulase from Geobacillus sp. TP-1 was isolated from Tapovan hot spring soil sample. The BLASTn sequence analysis of 16S rRNA sequence revealed that the isolate belonged to the Geobacillus genus and shared the highest degree of sequence similarity (99.43%) with the different strains of Geobacillus subterraneus. The neighbour joining method of multiple sequence alignment revealed that the 16S rRNA sequence of Geobacillus sp. TP-1 shows maximum similarity with Geobacillus stearothermophilus strain S_YE6-1017-022. One-Factor-At-a-Time analysis was used to optimize the carbon source, nitrogen source, pH, temperature, inoculum size and growth profile with respect to cellulase production. When compared to un-optimized basal media, optimised medium increased cellulase production by around 3.6 times. The Plackett Burman factorial design was employed to identify the critical medium components influencing cellulase activity and temperature was determined to have a significant effect on overall cellulase production. The current strain was capable of utilising lignocellulosic waste as an alternative carbon source. The use of sugarcane molasses and wheat bran as carbon sources resulted in a significant increase (~ 7.2 fold) in cellulase production in the current study, indicating the bacterium's potential for valorising lignocellulosic biomass into value-added products, which encourages its use in lignocellulosic-based bio refineries. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-024-01258-x.

Comparative bacteriome and antibiotic resistome analysis of water and sediment of the Ganga River of India.

A comparative analysis between water and sediment can provide better information to understand the dynamics of the inhabitant microbiome and their respective antibiotic resistance genes of a river. Therefore, the present investigation was carried to explore the limited information available on bacterial microbiome and their predictive antibiotic resistance genes (ARGs) from water and sediment of the Ganga River. The study utilized the NGS-based sequences previously submitted under the accession number (PRJNA847424 and PRJNA892876). Overall analysis revealed that twenty phyla and fifty-four genera were shared between the water and sediment of the Ganga River. Of them, nine phyla and nineteen genera were observed as significantly different (p-value < 0.05). Where the majority of the genera were associated with the sediment samples over the water that identify the sediment samples as more diverse for species richness. Similarly, seventy-six ARGs were shared between water and sediment samples. Of the ten abundant antibiotic resistance pathways, seven were relatively abundant in sediment samples as compared to the water. Vancomycin resistance genes were significantly more abundant among sediment samples, whereas ß-lactam resistance genes were equally distributed in water and sediment samples. The network analysis further revealed that five genera (Flavobacterium, Pseudomonas, Acinetobacter, Candidatus_divison CL5003, and Candidatus_division SWB02) showed a significantly positive correlation with six antibiotic resistance pathways (ß-lactam, vancomycin, multidrug resistance, tetracycline, aminoglycoside, and macrolide resistance pathways). The study comes out with several findings where sediment may be considered as a more atrocious habitat for evolving the resistance mechanisms against threatful antibiotics over the water samples of the Ganga River.

Comparative and analytical characterization of the oral bacteriome of smokeless tobacco users with oral squamous cell carcinoma.

Oral cavity squamous cell carcinoma (OSCC) is the most common type of head and neck cancer worldwide. Smokeless tobacco (SLT) has been well proven for its role in oral carcinogenesis due to the abundance of several carcinogens. However, the role of inhabitant microorganisms in the oral cavity of smokeless tobacco users has not yet been well explored in the context of OSCC. Therefore, the present investigation was conceived to analyze the oral bacteriome of smokeless tobacco users having OSCC (CP group). With the assistance of illumina-based sequencing of bacterial-specific V3 hypervariable region of 16S rDNA gene, 71,969 OTUs (operational taxonomic units) were categorized into 18 phyla and 166 genera. The overall analysis revealed that the oral bacteriome of the patients with OSCC, who were smokeless tobacco users, was significantly different compared to the healthy smokeless tobacco users (HTC group) and non-users (HI users). The appearance of 14 significantly abundant genera [FDR (false discovery rate) adjusted probability value of significance (p value) < 0.05] among the CP group showed the prevalence of tobacco-specific nitrosamines forming bacteria (Staphylococcus, Fusobacterium, and Campylobacter). The functional attributes of the oral bacteriome of the CP group can also be correlated with the genes involved in oncogenesis. This study is the first report on the oral bacteriome of Indian patients with OSCC who were chronic tobacco chewers. The results of the present study will pave the way to understand the influence of smokeless tobacco on the oral bacteriome of OSCC patients. KEY POINTS: • Oral bacteriome of OSCC patients differ from healthy smokeless tobacco (SLT) users and SLT non-users. • Smokeless tobacco influences the oral bacteriome of OSCC group. • Oral bacteriome specific diagnostics may be developed for pre-diagnosis of oral cancer.

Genomic attributes of thermophilic and hyperthermophilic bacteria and archaea.

Thermophiles and hyperthermophiles are immensely useful in understanding the evolution of life, besides their utility in environmental and industrial biotechnology. Advancements in sequencing technologies have revolutionized the field of microbial genomics. The massive generation of data enhances the sequencing coverage multi-fold and allows to analyse the entire genomic features of microbes efficiently and accurately. The mandate of a pure isolate can also be bypassed where whole metagenome-assembled genomes and single cell-based sequencing have fulfilled the majority of the criteria to decode various attributes of microbial genomes. A boom has, therefore, been seen in analysing the extremophilic bacteria and archaea using sequence-based approaches. Due to extensive sequence analysis, it becomes easier to understand the gene flow and their evolution among the members of bacteria and archaea. For instance, sequencing unveiled that Thermotoga maritima shares around 24% of genes of archaeal origin. Comparative and functional genomics provide an analytical view to understanding the microbial diversity of thermophilic bacteria and archaea, their interactions with other microbes, their adaptations, gene flow, and evolution over time. In this review, the genomic features of thermophilic bacteria and archaea are dealt with comprehensively.

Taxonomic and functional profiling of Indian smokeless tobacco bacteriome uncovers several bacterial-derived risks to human health.

Smokeless tobacco (ST) consumption keeps human oral health at high risk which is one of the major reasons for oral tumorigenesis. The chemical constituents of the ST products have been well discussed; however, the inhabitant microbial diversity of the ST products is less explored especially from south Asian regions. Therefore, the present investigation discusses the bacteriome-based analysis of indigenous tobacco products. The study relies on 16S amplicon-based bacteriome analysis of Indian smokeless tobacco (ST) products using a metagenomic approach. A total of 59,15,143 high-quality reads were assigned to 34 phyla, 82 classes, 176 orders, 256 families, 356 genera, and 154 species using the SILVA database. Of the phyla (> 1%), Firmicutes dominate among the Indian smokeless tobacco followed by Proteobacteria, Bacteroidetes, and Actinobacteria (> 1%). Whereas, at the genera level (> 1%), Lysinibacillus, Dickeya, Terribacillus, and Bacillus dominate. The comparative analysis between the loose tobacco (LT) and commercial tobacco (CT) groups showed no significant difference at the phyla level, however, only three genera (Bacillus, Aerococcus, and Halomonas) were identified as significantly different between the groups. It indicates that CT and LT tobacco share similar bacterial diversity and poses equal health risks to human oral health. The phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt 2.0) based analysis uncovered several genes involved in nitrate/nitrite reduction, biofilm formation, and pro-inflammation that find roles in oral pathogenesis including oral cancer. The strong correlation analysis of these genes with several pathogenic bacteria suggests that tobacco products pose a high bacterial-derived risk to human health. The study paves the way to understand the bacterial diversity of Indian smokeless tobacco products and their putative functions with respect to human oral health. The study grabs attention to the bacterial diversity of the smokeless tobacco products from a country where tobacco consumers are rampantly prevalent however oral health is of least concern.

Taxonomic profiling and functional characterization of the healthy human oral bacterial microbiome from the north Indian urban sub-population.

Poor oral health has broad consequences that can be seen at personal as well as societal levels, especially in developing countries like India. We have limited information on the healthy oral cavity's inhabitant microorganisms that play a crucial role in overall oral health. In a comprehensive culture-independent approach, the bacterial composition of healthy human oral cavities was determined from a sub-population of northern India. During this study, 20 mouthwash-derived metagenomes were explored for identifying bacterial diversity using the 16S rRNA hypervariable V3 region with the MiSeq Illumina platform. On the taxonomy assignment of operational taxonomic units (OTUs), 20 assigned phyla and 162 genera were recovered among the participants. The mean relative abundance revealed that Streptococcus was the dominant genera among the participants. However, at inter-individual analysis, Neisseria and Haemophilus exhibited first-order dominance among five and three healthy individuals, respectively. Correlation studies indicate that Streptococcus shares a strong relationship with Rothia, Corynebacterium, Prevotella, and Veillonella, whereas it was negatively correlated with Neisseria, Aggregatibacter, Porphyromonas, and Fusobacteria like Gram-negative bacteria. Bacterial diversity showed insignificant differences at the level of age and gender within and between the participants. The results support several of the major findings of previous reports on the healthy oral microbiome of the Indian population, however, the present investigation further illustrates that demographic region leaves an impact on overall bacterial composition. The study will assist in a better understanding of the oral microbiome from region-specific Indian population that was otherwise highly under-represented.

Characterization of Oral Bacterial Composition of Adult Smokeless Tobacco Users from Healthy Indians Using 16S rDNA Analysis.

The present investigation is aiming to report the oral bacterial composition of smokeless tobacco (SLT) users and to determine the influence of SLT products on the healthy Indian population. With the aid of the V3 hypervariable region of the 16S rRNA gene, a total of 8,080,889 high-quality reads were clustered into 15 phyla and 180 genera in the oral cavity of the SLT users. Comparative analysis revealed a more diverse microbiome where two phyla and sixteen genera were significantly different among the SLT users as compared to the control group (p-value < 0.05). The prevalence of Fusobacteria-, Porphyromonas-, Desulfobulbus-, Enterococcus-, and Parvimonas-like genera among SLT users indicates altered bacterial communities among SLT users. Besides, the depletion of health-compatible bacteria such as Lactobacillus and Haemophilus also suggests poor oral health. Here, the majority of the altered genera belong to Gram-negative anaerobes that have been reported for assisting biofilm formation that leads in the progression of several oral diseases. The PICRUSt analysis further supports the hypothesis where a significant increase in the count of the genes involved in the metabolism of nitrogen, amino acids, and nicotinate/nicotinamide was observed among tobacco chewers. Moreover, this study has a high significance in Indian prospects where the SLT consumers are prevalent but we are deficient in information on their oral microbiome.

Microorganisms: crucial players of smokeless tobacco for several health attributes.

Global consumption of smokeless tobacco (SLT) reached 300 million users worldwide majorly from middle-income countries. More than 4000 chemical compounds represent it as one of the noxious consumable products by humans. Besides toxicants/carcinogens, the heavy microbial load on smokeless tobacco further keeps human health at higher risk. Several of these inhabitant microbes participate in biofilm formation and secrete endotoxin/mycotoxins and proinflammatory-like molecules, leading to several oral diseases. Tobacco-associated bacteria exhibit their role in tobacco-specific nitrosamines (TSNAs) formation and acetaldehyde production; both are well-documented carcinogens. Moreover, tobacco exhibits the potential to alter the oral microbiome and induce dysbiotic conditions that lead to the onset of several oral and systemic diseases. Traditional cultivation approaches of microbiology provide partial information of microbial communities of a habitat; therefore, microbiomics has now been employed to study the metagenomes of entire microbial communities. In the past 5 years, few NGS-based investigations have revealed that SLT harbors four dominant phyla (Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes) dominating Bacillus spp. and/or Pseudomonas spp. However, functional characterization of their genetic elements will be a more informative attribute to understand the correlation between inhabitant microbial diversity and their relatedness concerning abundance and diseases. This review provides an update on the microbial diversity of SLT and its associated attributes in human health. KEY POINTS: • Heavy microbial load on smokeless tobacco alarms for poor oral hygiene. • Inhabitant microorganisms of SLT participate in TSNA and biofilm formation. • SLTs alter the oral microbiome and causes oral dysbiosis.

Insights into the human oral microbiome.

Human oral cavity harbors the second most abundant microbiota after the gastrointestinal tract. The expanded Human Oral Microbiome Database (eHOMD) that was last updated on November 22, 2017, contains the information of approximately 772 prokaryotic species, where 70% is cultivable, and 30% belong to the uncultivable class of microorganisms along with whole genome sequences of 482 taxa. Out of 70% culturable species, 57% have already been assigned to their names. The 16S rDNA profiling of the healthy oral cavity categorized the inhabitant bacteria into six broad phyla, viz. Firmicutes, Actinobacteria, Proteobacteria, Fusobacteria, Bacteroidetes and Spirochaetes constituting 96% of total oral bacteria. These hidden oral micro-inhabitants exhibit a direct influence on human health, from host's metabolism to immune responses. Altered oral microflora has been observed in several diseases such as diabetes, bacteremia, endocarditis, cancer, autoimmune disease and preterm births. Therefore, it becomes crucial to understand the oral microbial diversity and how it fluctuates under diseased/perturbed conditions. Advances in metagenomics and next-generation sequencing techniques generate rapid sequences and provide extensive information of inhabitant microorganisms of a niche. Thus, the retrieved information can be utilized for developing microbiome-based biomarkers for their use in early diagnosis of oral and associated diseases. Besides, several apex companies have shown keen interest in oral microbiome for its diagnostic and therapeutic potential indicating a vast market opportunity. This review gives an insight of various associated aspects of the human oral microbiome.

16S rDNA-Based Amplicon Analysis Unveiled a Correlation Between the Bacterial Diversity and Antibiotic Resistance Genes of Bacteriome of Commercial Smokeless Tobacco Products.

The distribution of bacterial-derived antibiotic resistance genes (ARGs) in smokeless tobacco products is less explored and encourages understanding of the ARG profile of Indian smokeless tobacco products. Therefore, in the present investigation, ten commercial smokeless tobacco products were assessed for their bacterial diversity to understand the correlation between the inhabitant bacteria and predicted ARGs using a 16S rDNA-based metagenome analysis. Overall analysis showed the dominance of two phyla, i.e., Firmicutes (43.07%) and Proteobacteria (8.13%) among the samples, where Bacillus (9.76%), Terribacillus (8.06%), Lysinibacillus (5.8%), Alkalibacterium (5.6%), Oceanobacillus (3.52%), and Dickeya (3.1%) like genera were prevalent among these phyla. The phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt)-based analysis revealed 217 ARGs which were categorized into nine groups. Cationic antimicrobial polypeptides (CAMP, 33.8%), vancomycin (23.4%), penicillin-binding protein (13.8%), multidrug resistance MDR (10%), and ß-lactam (9.3%) were among the top five contributors to ARGs. Staphylococcus, Dickeya, Bacillus, Aerococcus, and Alkalibacterium showed their strong and significant correlation (p value < 0.05) with various antibiotic resistance mechanisms. ARGs of different classes (blaTEM, blaSHV, blaCTX, tetX, vanA, aac3-II, mcr-1, intI-1, and intI2) were also successfully amplified in the metagenomes of SMT samples using their specific primers. The prevalence of ARGs in inhabitant bacteria of smokeless tobacco products suggests making steady policies to regulate the hygiene of commercial smokeless tobacco products.

An improved protocol for metagenomic DNA isolation from low microbial biomass alkaline hot-spring sediments and soil samples.

High-quality, humic-acid-free pure DNA is a prerequisite for functional and sequence-based approaches of metagenomics. In the present investigation, an improved extraction buffer was developed by making a combination of powdered activated charcoal (2%; w/v), polyvinyl poly pyrrolidone (2%; w/v), and CaCl2 (2%; w/v). This trio significantly improved the purity and yield of the metagenomic DNA from the hot spring's hot and alkaline soil. The quality of extracted metagenomic DNA was successfully validated by PCR amplification and restriction enzymes. Besides, the thermophilic amylase encoding genes were also retrieved from these soil DNA samples. Extreme habitats I harbour low microbial biomass and, therefore, demand in-situ lysis of the microbial cells to access their genomes. The protocol can potentially extract DNA from geothermal spring habitats where the count of microbial cells is low.

The structural insights of L-asparaginase from Pseudomonas aeruginosa CSPS4 at elevated temperatures highlight its thermophilic nature.

In the present investigation, a novel thermophilic L-asparaginase (Asn_PA) from Pseudomonas aeruginosa CSPS4 was investigated to explore its structural insights at elevated temperatures. Sequence analysis of Asn_PA depicted three conserved motifs (VVILATGGTIAG, DGIVITHGTDTLEETAYFL, and, LRKQGVQIIRSSHVNAGGF), of them, two motifs exhibit catalytically-important residues i.e., T45 and T125. A homology modelling-based structure model for Asn_PA was generated with 4PGA as the top-matched template. The predicted structure was validated and energy was minimized. Molecular docking was carried out cantered at the active site for asparagine and glutamine as its substrate ligands. The enzyme-substrate interaction analysis showed binding affinities of - 4.8 and - 4.1 kcal/mol for asparagine and glutamine respectively. Molecular dynamics (MD) simulation studies showed a better stability of Asn_PA at temperatures of 60 °C, over 40, 50 and, 80 °C, making this enzyme a novel L-asparaginase from other mesophilic P. aeruginosa strain. The trajectory analysis showed that RMSD, Rg, and, SASA values correlate well with each other in the different tested temperatures during the MD analysis. Thus, the present findings encourage extensive characterization of the Asn_PA using laboratory experiments to understand the structural behavior of the active site loop in an open or closed state with and without the substrate molecules. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04072-w.

Cloning, expression, and characterization of a novel thermo-acidophilic l-asparaginase of Pseudomonas aeruginosa CSPS4.

In the present investigation, a soil isolate Pseudomonas aeruginosa CSPS4 was used for retrieving the l-asparaginase encoding gene (Asn_PA) of size 1089 bp. The gene was successfully cloned into the pET28a (+) vector and expressed into E. coli BL21(DE3) for characterization of the protein. The recombinant rAsn_PA enzyme was purified by affinity chromatography using Ni-NTA2+ resins. Molecular weight analysis using SDS-PAGE unveiled rAsn_PA as a monomeric protein of molecular weight ~ 35 kDa. On characterization, the recombinant rAsn_PA showed optimum pH and temperature of 6.0 and 60 °C, respectively, along with significant stability at 50-70 °C, along with 50% residual activity at 80 °C after 3 h of incubation. Similarly, the rAsn_PA exhibited asparaginase activity over a broad pH range between 4 and 8. The enzyme was not significantly inhibited in the presence of detergents. The rAsn_PA was grouped into the asparaginase-glutaminase family II due to the glutaminase activity. The purified rAsn_PA showed antitumor activity by exhibiting a cytotoxic effect on three different cell lines, where IC50 of purified rAsn_PA was 2.3 IU, 3.7 IU, and 20.5 IU for HL-60, MOLM-13, and K-562 cell lines, respectively. Thus, recombinant rAsn_PA of P. aeruginosa CSPS4 may also be explored as an antitumor agent after reducing or minimizing the glutaminase activity. Thermo-acidophilic properties of rAsn_PA make it a novel enzyme that needs to be further investigated.

Unveiling the Immunostimulatory Potential of Rhus Toxicodendron in Immunocompromised Balb/C Mice Induced with Cyclophosphamide.

This study investigated how Rhus toxicodendron (RT) (6C, 30C, and 200C) can boost the immune system of BALB/c mice that were given cyclophosphamide (CPM), which is an anticancer drug that weakens the immune system. RT, known for its historical use in traditional homeopathic remedies, has demonstrated immunomodulatory and anti-inflammatory effects in various experimental models. To test the immune-boosting effects of RT, CPM (80 mg/kg) was given intraperitoneally to mice on days 4, 8, and 12 of the study but not to the normal control group. CPM-induced immunosuppression led to significant decreases in red blood cell (RBC), white blood cell (WBC), and hemoglobin (Hb) levels, and reduced spleen and thymus indices. Phagocytic activity, cytokine concentrations, and spleen architecture were also adversely affected. RT treatment, particularly at 200C, significantly ameliorated these effects, improving RBC, WBC, and Hb levels. Furthermore, RT partially prevented CPM-induced atrophy of immune organs. Treatment positively influenced cytokine production at both the protein and mRNA levels, restoring immune balance. Histopathological results confirmed that RT stimulated the immune system. The cells were more stable, and the white pulp in the spleen was arranged in a regular pattern. These findings suggest that RT may serve as an adjunctive immunostimulant therapy for conditions characterized by immunosuppression. However, further investigations in other immunocompromised states must validate these results before considering human clinical trials.

Investigation of The Effect of Metal-based Medicine Arsenicum album on Humoral Immune Response in SRBC-immunized Mice.

BACKGROUND: In complementary and alternative medicinal systems, the Arsenicum album in ultra-high dilution was used in various therapeutic conditions, considering its effects on the body's immune system, including the COVID-19 pandemic. However, scientific evidence regarding its immunomodulatory effects is insufficient. OBJECTIVE: The current study aimed to investigate the immunomodulatory effects of Arsenicum album in an experimental mouse model. MATERIALS AND METHODS: Immunomodulatory activity of potentized dilutions of Arsenicum album i.e., 6C, 30C, 200C in BALB/c mice was evaluated by humoral antibody titer and delayed- type hypersensitivity assays wherein a fixed concentration (0.5 ml of 1× 109 cells/ml) of freshly prepared sheep RBC was administered as a foreign antigen to generate primary and secondary antibodies. RESULTS: Arsenicum album showed significant immunomodulatory activity by increasing primary antibody titer evaluated on day 21 of the treatment in all the dilutions as compared to SRBC and vehicle control group in humoral immune response assay without showing any effect on delayed-type hypersensitivity. CONCLUSION: The results of this preliminary study indicate that oral administration of Arsenicum album has the potential to augment primary humoral response at all dilutions. Hence, the possibility of using the Arsenicum album could be explored to treat immunological conditions, infections, etc., as an alternative therapy alongwith modern medicines.

Smokeless Tobacco Harbors Bacteria Involved in Biofilm Formation as Well as Salt and Heavy Metal Tolerance Activity.

In our previous culture-independent study on smokeless tobacco products, we have observed a strong positive correlation between several bacteria and genes involved in nitrate/nitrite reduction, biofilm formation, and pro-inflammation. Therefore, the present investigation was carried out to analyze the inhabitant bacterial population of the Indian ST products for assessing the health-associated risk attributes using culture-dependent approach. Traditional cultivation approaches recovered several bacterial isolates from commercial ST products on different culture media. A high colony formation unit (CFU) count was observed that ranged from 173 × 104 to 630.4 × 105 per gram of ST products. Of the 74 randomly selected and distinct bacterial isolates, 17 isolates showed a significantly enhanced growth (p-value < 0.05) in the presence of the aqueous tobacco extract. On biochemical characterization, these bacteria were identified as the member of Bacillus, Enterobacter, Micrococcus, Providencia, Serratia, Pantoea, Proteus, and Pseudomonas. Most of these bacteria also exhibited biofilm-forming activity, where eight bacterial isolates were identified for strong biofilm-forming action. 16S rRNA-based molecular characterization of these bacteria identified them as Bacillus subtilis, Bacillus paralicheniformis, Enterobacter sp., Serratia marcescens, Pantoea anthophila, and Enterobacter cloacae. Moreover, these bacteria also exhibited the potential to withstand high salt and heavy metal concentrations. The findings demonstrate that Indian ST products are heavily populated with wide bacterial species exhibiting potential in biofilm formation, heavy metal resistance, and salt tolerance.

Ganga River sediments of India predominate with aerobic and chemo-heterotrophic bacteria majorly engaged in the degradation of xenobiotic compounds.

Sediment provides a stagnant habitat to microbes that accumulate organic matter and other industrial pollutants from the upper layer of the water. The sediment of the Ganga River of India is overlooked for exploring the bacterial diversity despite their taxon richness over the water counterpart. To enrich the limited information on the bacterial diversity of the Ganga River sediment, the present study was planned that relies on amplicon-based bacterial diversity of the Ganga River sediment by using bacterial-specific 16S hypervariable region (V3-V4). The Illumina MiSeq2500 platform generated 1,769,226 raw reads from the metagenomes of various samples obtained from ten sites in five major cities of Uttar Pradesh and Uttarakhand regions traversing the Ganga River. Taxonomy level analysis assigned 58 phyla, 366 order, and 715 genera of bacterial type. The high values of various diversity indices (Chao1, Shannon, and Simpson) in Kanpur sediment indicate the high bacterial richness compared to the Rishikesh sediment. However, several other ecological parameters (Shannon index, Simpson index, enspie _vector, and Faith_pd) were comparatively higher in Rishikesh sediment which is a comparatively less disturbed region by human activities over the other sediments samples studied here. Ganga River sediment dominates with Gram-negative, chemo-heterotrophic, and aerobic bacteria that chiefly belong to Proteobacteria, Acidobacteria, Chloroflexi, and Bacteroidota. The abundance of Nitrospira, Hydrogenophaga, Thauera, Vicinamibacteraceae, and Latescibacterota in the Ganga River sediment could be considered as the ecological indicators that find a significant role in the degradation of xenobiotic compounds. The PICRUSt-based analysis showed that ~ 35% of genes were involved in benzoate and aminobenzoate degradation where a significant portion of genes belong to nitrotoluene degradation (14%). Thus, the study uncovers a new perspective in the lineage of bacterial communities and their functional characterization of the Ganga River sediment.

Urbanization led to the abundance of Gram-negative, chemo-organo-heterotrophs, and antibiotic resistance genes in the downstream regions of the Ganga River water of India.

The present investigation assesses the bacterial microbiome and antibiotic resistance genes (ARGs) of the river Ganga from Uttarakhand (upstream region; US group) and Uttar Pradesh (downstream region; DS group) regions using a 16S rRNA amplicon-based metagenomic approach. Gram-negative, aerobic, and chemo-organotrophic bacteria made up the majority of the bacterial genera during the overall analysis. Physicochemical analysis revealed a higher concentration of nitrate and phosphate in the downstream sites of the Ganga River. The prevalence of Gemmatimonas, Flavobacterium, Arenimonas, and Verrucomicrobia in the water of the DS region indicates a high organic load. Pseudomonas and Flavobacterium emerged as the most prevalent genera among the 35 significantly different shared genera (p-value < 0.05) in the US and DS regions, respectively. Overall antibiotic resistance analysis of the samples showed the dominance of ß-lactam resistance (33.92%) followed by CAMP (cationic antimicrobial peptide) resistance (27.75%), and multidrug resistance (19.17%), vancomycin resistance (17.84%), and tetracycline resistance (0.77%). While comparing, the DS group exhibited a higher abundance of ARGs over the US group, where the CAMP resistance and ß-lactam ARGs were dominant in the respective regions. The correlation (p-value < 0.05) analysis showed that most bacteria exhibit a significant correlation with tetracycline resistance followed by the phenicol antibiotic. The present findings draw attention to the need for regulated disposal of multiform human-derived wastes into the Ganga River to reduce the irrepressible ARGs dissemination.