Sensing of azo toxic dyes using nanomaterials and its health effects - A review.

Development of science has taken over our lives and made it mandatory to live with science. Synthetic technology takes more than it has given for our welfare. In the process of meeting the demand of the consumers, industries supported synthetic products to meet the same. One such sector that employs synthetic azo dyes for food coloring is the food industry. The result of the process is the production of a variety of colored foods which looks more appealing and palatable. The process not only meets the consumer's demand it also has an impact on customers' health because the consumption of azo-toxic dye-treated foods regularly or in direct contact with synthetic azo dyes can also cause severe human health consequences. Nanotechnology is a rapidly evolving branch of research in which nanosensors are being developed for a variety of applications, including sensing various azo-toxic dyes in food products, which provides a wider scope in the future, with the innovation in designing different nanosensors. The current review focuses on the different types of nanosensors, their key role in sensing, and the sensing of azo toxic dyes using nanosensors, their advantages over other sensors, applications of nanomaterials, and the health impacts of azo dyes on humans, appropriate parameters for maximum permissible limits, and an Acceptable Daily Intake (ADI) of azo toxic dye to be followed. The regulations followed on the application of colorants to the food are also elaborated. The review also focuses on the application of enzyme-based biosensors in detecting azo dyes in food products.

Isolation of moderately halotolerant bacterial strains, associated with coral Porites lutea from Gulf of Kachchh: Antibacterial activity and PHB production.

The marine ecosystem contains a solution for food, shelter, pharmaceutical problems and has a key role in the economy of the country as tourism. The Gulf of Kachchh, known for its high tides and the coral reefs are less explored for its antibiotic activity due to the coral bleaching and diseases. The bacterial strains in the coral Porites lutea are determined to possess antibiotic activity against bacterial strains such as E.coli, P. aeruginosa, S. aureus and S. faecalis. Among thirty bacterial strains isolated from the tissue, skeleton and mucus, two bacterial strains resulted in the better antagonistic activity. The antibiotic compound extracted from both the bacteria elucidated to be 4-[(2E)-4-hydroxypent-2-en-1-yl]-5,6-dihydro-2H-pyran-2-one. Further, through ADMET prediction it was inferred that it is an effective drug lead as it reports less toxicity and better drug-likeliness. The study also includes the effect of Poly Hydroxy Butarate (PHB) production by the isolated bacterial strain.

Prevalence of differential microbiome in healthy, diseased and nipped colonies of corals, Porites lutea in the Gulf of Kachchh, north-west coast of India.

Coral reefs are constantly subjected to multiple stresses like diseases and fish predation, which can profoundly influence the coral microbiome. This study investigated the differences in bacterial community structure of healthy, white syndrome affected and blenny nipped coral colonies of Porites lutea, collected from the coral reefs of Gulf of Kachchh, north-west coast of India. Present study observed that the stressed coral colonies harbored more OTUs and contained higher diversity values compared to healthy corals colonies. Similarly, beta diversity analysis indicated the dissimilarities among the three coral samples analyzed. Though the taxonomy analysis indicated bacterial phyla like Proteobacteria, Firmicutes, Bacteroidetes, and Actinobacteria among the entire coral samples studied, there was a variation in their relative abundances. Huge variations were observed in the relative dominance at the bacterial genera level. About 13phyla and 11 genera was identified in healthy coral. The PBN sample was found to contain Proteobacteria, Cyanobacteria, Verrucomicrobia, and Lentisphaerae as dominant phyla and Endozoicomonas, Dyella, Woeseia, and Winogradskyella as dominant genera. The PWS sample contained Proteobacteria, Lentisphaerae, Spirochaetes, and Tenericutes as dominant phyla and Endozoicomonas, Arcobacter, Sunxiuqinia, and Carboxylicivirgia as dominant genera. Among the healthy samples, sequences belonging to Uncultured Rhodospirillaceae were dominant, while Woeseia and sequences belonging to Uncultured Rhodovibrionaceae were dominant among the blenny nipped white syndrome infected corals. Although any previously established pathogen was not identified, present study revealed the presence of a potentially pathogenic bacterium, Arcobacter, among the diseased corals. It also demonstrated a dynamic microbiome among the Porites lutea colonies on subjecting to various stresses.

Biological approach in deinking of waste paper using bacterial cellulase as an effective enzyme catalyst.

Paper has become the basic elixir in everyone's activities and usage of paper has increased day by day, the waste generated by paper is also enormous. The primary source of paper is wood (tree) yet, waste paper is environmentally good and biodegradable; however, it is the primary source of deforestation. Current research aims to find an alternate way to recycle paper in the biological approach. Hence in our work, twelve cellulose-producing bacteria were isolated, out of which one bacterial strain proved to be the best. Cellulase enzyme was extracted and purified, and used for enzymatic de-inking of photocopy papers. The optimal conditions for cellulase synthesis were at 60 °C, glucose as the only carbon source, and potassium nitrate as the nitrogen source. The enzyme demonstrated excellent de-inking at a lower pulp consistency of 3% with a 20% enzyme dose. The cellulose and hemicellulose levels decreased, which can be attributed to fiber breaking. Further, the changes in the functional groups identified by Fourier-transform infrared spectroscopy analysis and the changes in the surface morphology of the pulp fibers were obtained using scanning electron microscope analysis.

Cellulase enzyme catalyst producing bacterial strains from vermicompost and its application in low-density polyethylene degradation.

Cellulose is the main polysaccharide present abundantly in the earth, an important substrate for the cellulase enzyme. Cellulases have attracted considerable attention due to its diverse application in different textile, detergent, leather, food, feed and paper industries. Among the cellulase producing microbes, bacteria have a faster growth compared to other microbes. The present study focuses on isolating bacterial strains (Bacillus pacificus and Pseudomonas mucidolens) from vermicompost. The study focused on extracting cellulase enzyme and its molecular weight using SDS-PAGE, which was determined to be 32Kda. The maximum enzyme activity resulted to be 0.12 U/mL and 0.17 U/mL after dialysis. The LDPE degradation was reported up to 30 days. Further, the growth conditions of the bacterial strains were optimised at different pH and temperature. The degradation of LDPE was determined using FTIR analysis, resulting in the peak changes (formation and shifts). The bacterial strains were morphologically characterized using Scanning Electron Microscopy. The bacterial strains Bacillus pacificus and Pseudomonas mucidolens were identified using 16 S rRNA sequencing.

Bioremediation of soil contaminated with toxic mixed reactive azo dyes by co-cultured cells of Enterobacter cloacae and Bacillus subtilis.

Azo dyes, known for its toxicity and mutagenicity, are used by textile industries. Bioremediation serves the best alternative treatment process due to its eco-friendly nature and cost-effectiveness. Degradation using individual bacteria promotes azo dye removal, while the degradation is enhanced using the immobilization method. Bio-carrier promotes the attachment of the bacterial strains and increases azo dye degradation. The present study focuses on the biodegradation of Reactive Red (RR), Reactive Brown (RB), Reactive Black dye (RBL), and mixed dyes in a soil slurry bioreactor containing free cells, co-culture, and immobilized cells. The physico-chemical analysis and soil characteristics were determined. The free cells of Bacillus cereus showed degradation of azo dyes - 79.42 ± 0.03% RR, 78.78 ± 0.02% RBL; 70.76 ± 0.03% RB, and 84.89 ± 0.05% of mixed dyes respectively. Enterobacter cloacae free cells resulted in degradation of 72.87 ± 0.01% RR, 75.21 ± 0.01% RBL, 74.50 ± 0.02% RB, and 73.39 ± 0.04% mixed dyes respectively. Co-cultured bacterial strains resulted in 77.18 ± 0.03% RR, 80.27 ± 0.02% RBL, 76.97 ± 0.02% RB and 86.29 ± 0.05% mixed dyes respectively. The immobilization of Bacillus cereus and Enterobacter cloacae on 2% corn starch resulted in 98.4 ± 0.01% degradation of RR, 89.8 ± 0.09% degradation of RB, 99.4 ± 0.05% of RBL, and 98.1 ± 0.08% of mixed reactive dyes respectively.

Acetaminophen degradation using bacterial strains isolated from winogradsky column and phytotoxicity analysis of dump site soil.

The increase in pollution increased the threat level of living organisms in the environment. Municipal Solid Waste is one of the most important wastes which contribute to polluted sites affecting livelihood. They pollute the water stream, marine environment ecology, soil fertility, and agriculture production. This, in turn, reduces the microflora of the marine environment, agricultural soil, and fertility. This could be analyzed by setting up a Winogradsky column using dumpsite soil samples. The current work was designed to study the municipal solid wastes from different dumpsite soil. Soil characterization revealed that the pH of Kodungaiyur and Otteri was 7.3 and 6.4. The bulk density was 0.067 g/cm3 and 0.069 g/cm3. The Porosity resulted to be 0.511 particle/volume and 0.513 particle/volume for Kodungaiyur and Otteri. The Kodungaiyur soil containing contaminants supplied with natural sources showed a 100% germination index, and Otteri soil containing contaminants supplied with natural sources showed a maximum vigour index. The presence of medicinal strips in the collected soil samples led to the study on Acetaminophen degradation. HB1 showed to be 79 ± 0.005% at optimum pH 5 containing 100 mg/L of Acetaminophen at day four among the isolated bacterial strains. Further, the intermediate formation was determined using FTIR and GC-MS. The isolated HB1 bacterial strain was identified as Staphylococcus hominis, which is heterotroph.

Analysis and microbial degradation of Low-Density Polyethylene (LDPE) in Winogradsky column.

Plastic pollution is threatening the world and the life in it. Cost-effective and eco-friendly treatment is the need of the hour. Treating plastics using chemical methods adds up chemicals into the environment with toxic byproducts. The physical method, a slow and expensive process, is not the better alternative. The process should rely on the environmental sources producing eco-friendly byproducts. The byproducts such as biofuel could be utilized for a sustainable environment, but the conversion of plastics into biofuel is expensive. Hence, biodegradation is the better, sustainable, and cost-effective process for plastic/any other pollutant removal. The study focuses on the construction of Winogradsky column using dumpsite soil. The column amended with Low-Density Polyethylene (LDPE) serves as a carbon source for native microbes. The utilization of microbes in every niche for the degradation enhances the degradation of LDPE. The Otteri soil resulted in 35.4 ± 0.3%, while Kodungaiyur and agriculture soil show 29.7 ± 0.6% and 19.8 ± 0.8%. The AFM analysis shows the disruption of smooth LDPE surface by forming ridges and grooves, which further confirms the occurrence of degradation. The FTIR analysis shows the incorporation of OH, CO, and other CO-O-CO in the CH backbone of LDPE. The oxidation of LDPE will aid in cleavage and result in the process of weathering. The tensile strength decreased after LDPE treatment (23.88 MPa - control, 22.50 MPa - Kodungaiyur, and 14.92 MPa - Otteri). Thus, utilizing the native microbes present in every niche enhances the degradation of pollutants.

Effect of shape and anthocyanin capping on antibacterial activity of CuI particles.

The recent upsurge of antibiotic-resistant infections has posed to be a serious health concern worldwide. In the present paper, the effect of shape & capping agent on the antibacterial activity (on Skin and Urinary Tract Infection (UTI) causing bacteria) of copper iodide (CuI) particles was probed. CuI synthesized without a capping agent was leaf-like, and that with one was prismatic in shape. XRD of the synthesized CuI confirmed their high crystalline nature and purity. The average crystallite sizes of capped and uncapped CuI were calculated to be 91.10 nm and 89.01 nm respectively from X-Ray powder diffraction data. The average particle size of capped CuI was found to be 492.7 nm and that of uncapped CuI was found to be 2.96 µm using HR-SEM analysis. The crystals obtained were further characterized using EDAX, FTIR spectroscopy and UV-Visible spectroscopy. Antibacterial activity of prismatic CuI capped with the flower extract of Hibiscus rosa-sinensis showed better activity than that of uncapped CuI. AFM analysis was carried out to confirm the proposed mechanism for antibacterial activity through the morphological changes on the bacterial cell wall in the presence of capped CuI. Molecular docking studies were performed to reaffirm the enhanced antibacterial activity of prismatic CuI further. The present study demonstrates the superior antibacterial propensity of prismatic CuI, consequently making it a potent antibacterial agent.

Integrated approach in LDPE degradation - An application using Winogradsky column, computational modeling, and pathway prediction.

Plastic pollution in the current scenario requires a sustainable and eco-friendly treatment process. Single-use plastics accumulate more than recyclable plastic wastes. Low-Density Polyethylene (LDPE) is one among the plastic family with inert characteristics. The traditional method, such as landfilling, develops pollution resistant micro-organisms. It is involved in the exploitation of the native microbes to the fullest. The soil of the Kodungaiyur, agriculture site, and Otteri dumpyard were used, which resulted in nearly 22.97 ± 2.7115%, 15.91667 ± 2.73775%, and 10.74 ± 0.502925% of LDPE degradation in 30 days without nutrient supplements. The enrichment of the column by organic nutrients increased the degradation of LDPE. The column enrichment was confirmed by the sulfur oxidizing bacteria (SOB) Escherichia coli and Pseudomonas stutzeri, which produced 195 mg/mL of sulfate ions. The FTIR of the LDPE degradation showed the polymer's oxygenation, while the electron microscopic images revealed cracks. In addition, an attempt was made to fit the experimental time-series data into suitable mathematical models to look at prediction and elementary forecasting. Three mathematical models, namely the customized moving averages model (CMAM), simple liinear regression model (SLRM), and a modified linear regression model (MLRM) with a lag, were able to represent the real experimental data complementarily.

Effect of chlorpyrifos on the earthworm Eudrilus euginae and their gut microbiome by toxicological and metagenomic analysis.

The earthworms are important soil invertebrates and play a crucial role in pedogenesis. The application of pesticides and prolonged exposure to pesticides causes mortality of earthworms apart from profoundly affecting the resident gut microbiome. The microbiome plays a significant effect on the metabolic processes associated with earthworms. The pesticide Chlorpyrifos (CPF) was studied for its toxicity on Eudrilus euginae by toxicity studies. The LC50 value of filter paper contact test and acute toxicity test was 3.8 mg/mL and 180 mg/kg. The prolonged exposure of earthworms to pesticide on reproductive toxicity resulted in the mortality of earthworms and absence of cocoon formation. Further, the effects of CPF on the whole gut microbiome of E. euginae was analyzed using a long amplicon Nanopore sequencing. Results indicated no fluctuations with Firmicutes and Bacteroidetes, that were found to be dominant at bacterial phyla level while at the genus level, remarkable differences were noticed. Clostridium dominated the earthworm gut prior to CPF exposure while Bacillus dominated after exposure. Similarly, the fungal members such as Ascomycota and Basidiomycota were observed to dominate the gut of earthworm at the phyla level before and after exposure to CPF. In contrast, Clavispora (65%) was the dominant genus before CPF exposure and Taloromyces (42%) dominated after the CPF exposure. Our study demonstrates the effect of CPF on the mortality of E. euginae while the amplicon sequencing established the unique microbiome of the gut in response to the CPF exposure.

Combined treatment of synthetic textile effluent using mixed azo dye by phyto and phycoremediation.

Phytoremediation is one of the biological approaches for remediating textile dyeing effluents. The objective of this study is the use of Pistia stratiotes, an aquatic macrophyte, which was found to degrade the maximum of 83% of mixed azo dye. A phytoreactor was designed and constructed to scale up the process of phytoremediation by P. stratiotes to treat 40 mg/l of synthetic textile effluent. Continuous flow phytoreactor fed with 40 mg/l (cycle 1) which showed maximum decolorization of 84%, COD removal was about 61%, BOD which was reduced up to 71.9%, and TDS removal was about 72% respectively. Further to remove the residual color and toxic effects of the dyes, Phycoremediation was followed for the mixed azo dyes using the microalgae Chlorella vulgaris which showed a maximum decolorization of 99% in the batch study and 74% in the scale-up study where the treated effluent was at the most minimal discharge. Phytotoxicity tests showed 80% of germination in treated effluent, and the plants in untreated wastewater had inhibited growth that indicates only 30% of germination. Such combined biological treatment techniques were put forward to be the most eco-friendly technology, which is cost-effective and attain zero discharge of the textile effluent.

Application of green synthesised copper iodide particles on cotton fabric-protective face mask material against COVID-19 pandemic.

Microorganisms cause variety of diseases that constitutes a severe threat to mankind. Due to the upsurge of many infectious diseases, there is a high requirement and demand for the development of safety products finished with antimicrobial properties. The study involves the antimicrobial activity of natural cotton coated with copper iodide capped with Hibiscus rosa-sinensis L. flower extract (CuI-FE) which is rich in anthocyanin, cyanidin-3-sophoroside by ultrasonication method. The coated and uncoated cotton fabric was characterised through XRD, SEM, AFM, tensile strength and UV-Visible spectroscopic techniques. XRD confirmed the formation of CuI particles, SEM showed that CuI-FE was prismatic in shape. The average size of CuI-FE particles was found to be 552.45 nm. Anti-bacterial studies showed copper iodide particles to be a potent antimicrobial agent. AFM images confirmed the rupture of bacterial cell walls in the presence of prismatic CuI-FE. In-vitro cytotoxicity investigation of CuI-FE was performed against cancer and spleen cell lines to evaluate the cell viability. Cytotoxicity analysis revealed the IC50 value of 233.93 µg/mL in the presence of CuI-FE. Molecular docking study was also carried out to understand the interaction of CuI-FE with COVID-19 main protease. This paper has given an insight on the usage of CuI-FE coated on the cotton fabric that has proved to have strong inhibition against the nano ranged bacterial, cancerous cell line and a strong interaction with the COVID-19 protease. Such eco-friendly material will provide a safe environment even after the disposable of medical waste from the infectious diseases like influenza and current pandemic like COVID-19.

Extrication of the Microbial Interactions of Activated Sludge Used in the Textile Effluent Treatment of Anaerobic Reactor Through Metagenomic Profiling.

Industrial effluents are potential threats to water bodies owing to the chemicals they contain to create pollution. Activated sludge effluents represent an ecosystem of multifaceted and interactive microbial consortia that flourish with different genetic as well as metabolic potential. This study is applied to a nanopore sequencing to understand the microbial organisms involved in degradation pathways, and their interaction among them. The taxonomic profile determined the occurrence of Proteobacteria, Actinobacteria, Terrabacteria, bacteria, and Firmicutes with the dominance of Burkholderiales. Burkholderia pseudomallei was found to be 13.79% of the classified reads. The Gene ontology evaluation revealed that mobile elements and tRNA genes were the predominant genetic composition of the community with 16% of the total genes. The functional annotation of genes ensured the presence of genes encoding various types of RNA, homo and heteromultimeric proteins and pseudogenes as well. Pathways that involved in effluent treatment such as amines, aromatic, organic, and aromatic compound degradation were also illustrated. Amino acyl tRNA charging, signal transduction, and hormone degradation were the pathways that are identified to be common in all the organisms of the activated sludge. The study elaborated on the xenobiotic degradation that is exclusive of the predominant Burkholderiales and the interaction of them in the community as a whole. The present study revealed the genes, proteins, and the pathways of the activated sludge microbiome which will enhance the perceptions of the core mechanisms of effluent degradation.