Eco-toxicological effect of a commercial dye Rhodamine B on freshwater microalgae Chlorella vulgaris.

In this study, the acute toxicity effects of a fluorescent xanthene dye, Rhodamine B (RhB), widely used in textile, paper, and leather industries was investigated on a freshwater microalgae Chlorella vulgaris. The acute toxicity of RhB on C. vulgaris was determined by examining the growth, cell morphology, pigment production, protein content, and the activities of oxidative stress enzymes. Based on the results of the toxicity study of 24-96 h, the median inhibitory concentration (IC50) values ranged from 69.94 to 31.29 mg L-1. The growth of C. vulgaris was conspicuously inhibited by RhB exposure, and the cell surfaces appeared to be seriously shrunk in SEM analysis. The growth of C. vulgaris was hindered after exposure to graded concentrations (10-50 mg L-1) of RhB. A significant reduction in growth rate, pigment synthesis (chlorophyll a, chlorophyll b, and carotenoid), and protein content was recorded in a dose-dependent manner. After 96 h exposure of C. vulgaris to 50 mg L-1 RhB, chlorophyll a, chlorophyll b, carotenoids, and protein contents were reduced by 71.59, 74.90, 65.84, and 74.20%, respectively. The activities of the antioxidant enzymes peroxidase (POD), and catalase (CAT) also increased markedly in the presence of RhB. A notable effect was observed on oxidative enzymes catalase and peroxidase, indicating that oxidative stress may be the primary factor in the inhibition of growth and pigment synthesis. Consequently, the experimental acute toxicity data were compared to the QSAR prediction made by the ECOSAR programme. Results showed that the experimental acute toxicity values were 67.74-fold lower than the ECOSAR predicted values. The study provides convincing evidence for the metabolic disruption in the ubiquitous microalgae C. vulgaris due to the RhB dye toxicity.

Unbiased peptoid cell screen identifies a peptoid targeting newly appeared cell surface vimentin on tumor transformed early lung cancer cells.

To identify potential new reagents and biomarkers for early lung cancer detection we combined the use of a novel preclinical isogenic model of human lung epithelial cells comparing non-malignant cells with those transformed to full malignancy using defined oncogenic changes and our on-bead two color (red and green stained cells) (OBTC) peptoid combinatorial screening methodology. The preclinical model used normal parent lung epithelial cells (HBEC3-KT, labeled with green dye) and isogenic fully malignant transformed derivatives (labeled with a red dye) via the sequential introduction of key genetic alterations of p53 knockdown, oncogenic KRAS and overexpression of cMYC (HBEC3p53, KRAS, cMYC). Using the unbiased OBTC screening approach, we tested 100,000 different peptoids and identified only one (named JM3A) that bound to the surface of the HBEC3p53, KRAS, cMYC cells (red cells) but not HBEC3-KT cells (green cells). Using the JM3A peptoid and proteomics, we identified the protein bound as vimentin using multiple validation approaches. These all confirmed the cell surface expression of vimentin (CSV) on transformed (HBEC3p53, KRAS, cMYC) but not on untransformed (HBEC3-KT) cells. JM3A coupled with fluorophores was able to detect and stain cell surface vimentin on very early stage lung cancers but not normal lung epithelial cells in a fashion comparable to that using anti-vimentin antibodies. We conclude: using a combined isogenic preclinical model of lung cancer and two color screening of a large peptoid library, we have identified differential expression of cell surface vimentin (CSV) after malignant transformation of lung epithelial cells, and developed a new peptoid reagent (JM3A) for detection of CSV which works well in staining of early stage NSCLCs. This new, highly specific, easy to prepare, CSV detecting JM3A peptoid provides an important new reagent for identifying cancer cells in early stage tumors as well as a resource for detection and isolating of CSV expressing circulating tumor cells.

Application of Microalgal Physiological Response as Biomarker for Evaluating the Toxicity of the Textile Dye Alizarin Red S.

Textile dyes are becoming a growing threat to the environment. This report presents the findings of the study on the toxicity of the textile dye Alizarin Red S on two freshwater microalgae. The acute toxicity assay revealed that 96-h EC50 values of Chlorella vulgaris and Spirulina platensis were 29.81 mg/L and 18.94 mg/L respectively. The pigments chlorophyll-a, b and carotenoids in C. vulgaris on 96-h exposure to the dye were 2.91, 3.29 and 3.01 times lower in analogy to control whereas Spirulina platensis showed 2.89and 2.56 fold decrease in chlorophyll-a and carotenoid content than control. After the test period of 96-h with dye, the protein content of C. vulgaris and S. platensis were 2.33 and 1.77 times lower compared to the control. The growth inhibition rate, pigment as well as the protein content declined in compliance with the rise in dye concentration, which anticipate paradigm about the toxic effects of the textile dye.

A novel peptidomimetic therapeutic for selective suppression of lung cancer stem cells over non-stem cancer cells.

Cancers are highly heterogeneous and typically contain a small subset of drug-resisting cells called tumor initiating cells or cancer stem cells (CSCs). CSCs can self-renew, divide asymmetrically, and often cause tumor invasion and metastasis. Therefore, treatments specifically targeting CSCs are critical to improve patient survival. Recently, we identified a highly specific peptidomimetic (peptoid - PCS2) that selectively binds to the CSC subpopulation of lung cancer over the remaining cancer cells (non-CSCs). Subsequently, we identified plectin as the target of PCS2. Plectin is an intracellular structural protein, which is involved in tumor invasion and metastasis when it appears on cell surface. While PCS2 monomer did not display any anti-cancer activity, we designed a series of homo-dimeric versions of PCS2, and identified PCS2D1.2 optimized homo-dimer that displayed highly specific cytotoxicity towards CSCs over non-CSCs. PCS2D1.2 effectively blocked the in vitro colony formation and cell migration, hallmarks of CSCs. Furthermore, PCS2D1.2 reduced the in vivo tumor formation. In both in vitro and in vivo studies, PCS2D1.2 effectively reduced plectin expression and/or plectin-rich CSCs, but had no effect on non-CSCs. Therefore, PCS2D1.2 has the potential to be developed as a highly CSC specific drug candidate, which can be used in combination with current anti-cancer drugs.

"Molecular Masks" for ACE2 to Effectively and Safely Block SARS-CoV-2 Virus Entry.

Coronavirus Disease 2019 (COVID-19) remains a global health crisis, despite the development and success of vaccines in certain countries. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, uses its spike protein to bind to the human cell surface receptor angiotensin-converting enzyme 2 (ACE2), which allows the virus to enter the human body. Using our unique cell screening technology, we identified two ACE2-binding peptoid compounds and developed dimeric derivatives (ACE2P1D1 and ACE2P2D1) that effectively blocked spike protein-ACE2 interaction, resulting in the inhibition of SARS-CoV-2 pseudovirus entry into human cells. ACE2P1D1 and ACE2P2D1 also blocked infection by a D614G mutant pseudovirus. More importantly, these compounds do not decrease ACE2 expression nor its enzyme activity (which is important in normal blood pressure regulation), suggesting safe applicability in humans.

Toxicity Evaluation of Six Textile Dyes on Growth, Metabolism and Elemental Composition (C, H, N, S) of Microalgae Spirulina platensis: The Environmental Consequences.

A concentration-dependent decrease in growth rate and pigment concentration of the blue-green alga Spirulina platensis was recorded after the exposure to graded (5-40 ppm) concentration of six textile dyes. The profile of vital elements (C, H, N, S) also showed a significant variation due to dye toxicity. The algal population showed up to 50% decrease in protein content after exposure to the dyes. Among the pigments, the dye exposure resulted in > 90% decreases in phycocyanin however, total chlorophyll and carotenoids exhibited up to a 50% decrease compared to control. The findings indicate that the unregulated discharge of textile dyes will directly impact the photoautotrophic organisms leading to ecological imbalance in aquatic ecosystems. Overall observations of the report provide baseline information about the toxicity of textile dyes and giving a better insight into the little-understood mechanisms of dye toxicity.

Identification of the minimum pharmacophore of lipid-phosphatidylserine (PS) binding peptide-peptoid hybrid PPS1D1.

We previously reported a unique peptide-peptoid hybrid, PPS1 that specifically recognizes lipid-phosphatidylserine (PS) and a few other negatively charged phospholipids, but not neutral phospholipids, on the cell membrane. The dimeric version of PPS1, i.e., PPS1D1 triggers strong cancer cell cytotoxicity and has been validated in lung cancer models both in vitro and in vivo. Given that PS and other negatively charged phospholipids are abundant in almost all tumor microenvironments, PPS1D1 is an attractive drug lead that can be developed into a globally applicable anti-cancer agent. Therefore, it is extremely important to identify the minimum pharmacophore of PPS1D1. In this study, we have synthesized alanine/sarcosine derivatives as well as truncated derivatives of PPS1D1. We performed ELISA-like competitive binding assay to evaluate the PS-recognition potential and standard MTS cell viability assay on HCC4017 lung cancer cells to validate the cell cytotoxicity effects of these derivatives. Our studies indicate that positively charged residues at the second and third positions, as well as four hydrophobic residues at the fifth through eighth positions, are imperative for the binding and activity of PPS1D1. Methionine at the first position was not essential, whereas the positively charged Nlys at the fourth position was minimally needed, as two derivatives that were synthesized replacing this residue were almost as active as PPS1D1.

Chronic toxicity of sediment-bound triclosan on freshwater walking catfish Clarias magur: Organ level accumulation and selected enzyme biomarker responses.

Triclosan (TCS) is a biocide widely used in personal care and medicinal products. TCS persists in sediments and has been detected worldwide, making sediments a vital route of TCS exposure to aquatic organisms. This experiment explored the bioaccumulation and toxicological effects of TCS-contaminated sediment. The study revealed that the half-life of TCS in the sediment-water system was 21.52 days. Exposure of Clarias magur juveniles to 0.4 and 0.8 mg kg-1 TCS-spiked sediment resulted in high Biota-Sediment Accumulation Factor (BSAF) with the highest bioaccumulation in the liver (29.62-73.61 mg kg-1), followed by gill (9.22-17.57 mg kg-1), kidney (5.04-9.76 mg kg-1), muscle (2.63-4.87 mg kg-1) and brain (1.53-3.20 mg kg-1). Furthermore, a concentration-dependent increase in oxidative stress biomarkers such as superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) was documented during 45 days of exposure in gill, liver, kidney, muscle, and brain tissues of exposed fish. A similar increasing trend was also recorded for liver transaminase enzymes such as glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) during the experimental period compared to control. Serum biochemical analysis revealed a significant time and concentration-dependent increase in serum glucose, serum GOT, and serum GPT, while serum total protein and albumin decreased significantly during exposure. These findings demonstrate high bioaccumulative and toxic nature of TCS in fish, promoting multiple physiological and biochemical dysfunctions through sediment exposure. The study underscores the urgent need for strengthened regulations and robust monitoring of triclosan across various environmental matrices, including sediment, to mitigate the detrimental impacts of TCS effectively.

Evaluation of acute toxicity of an emerging contaminant Oxybenzone on an ecologically important aquatic macrophyte Lemna minor.

Oxybenzone is an ultraviolet filter frequently used in Personal Care Products, plastics, furniture, etc. and is listed as an Emerging Contaminant. This report studied the acute toxicity of Oxybenzone to Lemna minor after exposure to graded concentrations of Oxybenzone for 7 days. IC50 for growth was found to be 8.53 mg L-1. The hormesis effect was reported at lower concentrations, while growth and pigments reduced from 2.5 to 12.5 mg L-1 in a concentration-related manner. The impact of Oxybenzone on protein and antioxidant enzymes- Catalase and Guaiacol Peroxidase revealed less stress up to 2.5 mg L-1 than control, increasing further from 5 to 10 mg L-1. Enzyme activity decreased over-time but always remained higher than control over a period of 7 days. Thus, our findings reveal that indiscriminate discharge of Oxybenzone could be potentially toxic to the aquatic primary producers at higher concentrations, causing an ecological imbalance in aquatic ecosystems.

Anthropogenic risk assessment of riverine habitat using geospatial modelling tools for conservation and restoration planning: a case study from a tropical river Pranhita, India.

The riverine ecosystem provides multiple benefits to human community and contributes to the sustainable development of the ecoregion. The growing dependency on these ecosystems has largely contributed to aggravating the ecological risks, habitat degradation, and loss of ecosystem services. The present study evaluates the ecological risk emanating from nine anthropogenic stressors including river use, hydro-morphology, catchment pollution, and biological stressor on river Pranhita in Godavari Basin of Peninsular India using InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) Habitat Risk Assessment model. The primary field survey, remote sensing, and secondary data-assisted spatial modelling results revealed low ecological risk (R = 0.65 of 3) in river Pranhita due to anthropogenic activities. Sediment loading, the inflow of nitrogen, and habitat fragmentation were the major stressors with relatively higher risk score (> 1); influence on a sizeable portion of riverine habitat (29-75% of the total area under high-risk zone) indicates the mounting threat from catchment activities. The low-risk value observed in protected river reaches as compared to unprotected areas is likely to be influenced by the abundant presence of intact riparian vegetation which mitigate the catchment stressors and minimal anthropogenic activity within protected areas. This study demonstrates the application of InVEST HRA model for ecological risk assessment of riverine ecosystems and fish assemblages along with their input data generation framework. This has the potential for prioritization of sensitive habitats based on computed ecological risk and stressor identification based on their exposure and consequences for developing appropriate mitigation measures. This model is spatially explicit and accommodates user-defined criteria for ecosystem-level assessment at a regional and national scale to facilitate the resource managers and policymakers for conservation and restoration planning and implementation of targeted management measures for sustainable development.

Seasonal distribution and abundance of microplastics in the coastal sediments of north eastern Arabian Sea.

The present study reports site-specific data on the seasonal variation in microplastic abundance and characteristics in coastal sediments along the North Eastern Arabian Sea, India. The abundance of MP in coastal sediments ranged from 4400 to 15,300 items/kg dry weight (DW), with the dominance of the size ranging between 100 and 500 µm. In the studied sediment samples, fibers were the most dominant form, followed by fragments. Ten different microplastics polymers were recorded during the study with dominance of polyethylene, polyester, polyamide and all the recorded plastic items in the sediments were denser than water, except polyethylene. The mean abundance of MP in sediments was significantly higher in the monsoon season. During this season, freshwater flow increases to the sea, which brings a higher concentration of microplastics from catchment areas. For a better insight, more time-series data and research are required to assess the source of MP pollution, understand spatial-temporal variations in MP abundance and their possible hazardous impacts on marine organisms and the environment.

Sugarcane bagasse biochar enhances the growth parameters, haematological parameters, and enzyme activities of genetically improved farmed tilapia (GIFT) reared in inland saline water.

In the present scenario, waste management, especially agro-waste, is one of the major challenges. India is an agrarian country and the economy depends on agriculture and a huge amount of agro-wastes are generated. In this study, biochar was prepared from paddy straw and sugarcane bagasse and was used in the feed of genetically improved farm tilapia (GIFT) at 0.5% (w/w) basis to study its effect on growth and haematological parameters. An experiment was carried out in triplicate in 500-l capacity FRP tanks comprising two treatments and one control. Tanks were filled with inland saline soil to maintain 25-cm soil's bed and water with 12 ppt salinity. A total of 22 fish having an average length of 5.14 ± 0.07 cm and weight of 4.8 ± 0.05 g were stocked in each tank; the fish were fed at apparent satiation level, twice daily for 45 days. It was observed that growth parameters like SGR% (specific growth rate), weight gain (WG%), and feed conversion ratio (FCR) were significantly improved (p < 0.05) than the control. Biochar-enriched feed also significantly improved the haematological parameters like red blood cell (RBC), white blood cell (WBC), haemoglobin (Hb) haematocrit % (HCT), mean cell haemoglobin concentration (MCH), and MCV (mean cell volume) in treatment groups than the control. Feeding biochar as feed additives was also found to decrease catalase (CAT) and enhanced amylase and lipase activities in treatments as compared to control (p < 0.05). It can be concluded that the application of biochar as a feed additive enhanced the growth and overall health of the fish, and it can enhance fish production. However, biochar from sugarcane bagasse was found to be more effective than the paddy straw biochar in the diet of tilapia (GIFT).

Palladium-catalyzed Sonogashira-coupling conjoined C-H activation: a regioselective tandem strategy to access indolo- and pyrrolo[1,2-a]quinolines.

An operationally simple approach for the regioselective tandem synthesis of indolo[1,2-a]quinolines 4a-v and pyrrolo[1,2-a]quinolines 5a-k from 1-(2-bromophenyl)-1H-indole/pyrrole/imidazole 1a-c, 2a,b by the palladium-catalyzed sequential C-C bond formation is described. The developed approach involves the palladium-catalyzed Sonogashira coupling followed by the intramolecular C-C bond formation via C-H activation, which leads to the formation of 6-endo-dig cyclized product. This synthetic methodology accommodates wide functional group variation on alkyne, which proves to be advantageous for the structural and biological activity assessments.

Microplastics in the foreshore coastal waters, sediment, and coastal fauna of a highly populated megacity - A study on the effect of anthropogenic discharge on clams.

In this study, the microplastics (MPs) abundance, characteristics and their variations across three popular beaches of highly populated and largest megacity of India were documented using clams as an indicator species. The abundance of MPs in clams was 77.39 MPs items/g in soft tissue parts and 198.82 items/individual, while in coastal waters and sediments the abundance was 537.5 ± 95 items/L and 10,568.3 ± 3053.3 items/kg respectively. The observed higher microplastic diversity integrated (MDII) indicates numerous sources contributing to microplastics pollution and higher microplastic index (MPI) indicates greater bioavailability of MPs to clams. The bulk of the microplastics recovered from clams (55.78 %), coastal sediments (52.27 %) and coastal sea waters (54 %) belong to the <100 µm size range, and were identified as LDPE and polypropylene, polyamide and polystyrene. This investigation tried to validate the potential trophic transfer concerns associated with clam intake to both human health and marine ecology.

Microplastic pollution in coastal ecosystem off Mumbai coast, India.

Microplastics (MPs) are anthropogenic pollutants which can adsorb toxic substances from surrounding water and absorb into the fish body. During the present study, MPs were observed in water, sediment, and gastrointestinal tracts of marine biota samples collected from the coastal waters of Mumbai, India. The mean abundances of MPs recorded in water samples 372 ± 143 items/liter and 9630 ± 2947 items/kg dry weight (DW) in sediment samples. The mean abundance of MPs in pelagic fish species varied from 6.74 ± 2.74 to 9.12 ± 3.57 items/individual and in the demersal species the values ranged from 5.62 ± 2.27 to 6.6 ± 2.98 items/individual. Shape-wise, four type of MPs were observed in the surface waters, sediments and all studied species, predominantly fibers, followed by fragments, pellets/beads, and films. Seven different colors of MPs (red, blue, black, translucent, brown, green, and yellow) were observed from studied samples. MPs of size below 250 µm formed the dominant size in the surface water, sediments, and biota samples except Bombay duck and Malabar sole fish. Based on Raman spectroscopy analysis, eleven types of plastic polymers identified from all studied samples. Thus, presence of MPs in studied biota indicates the transfer of MPs through interlinked food chain/web to higher trophic levels and the occurrence of MPs in the fish gut underlines the necessity of more studies on processing interventions for reducing the microplastic contamination in fish for human consumption.

A peptoid interleukin-15 receptor antagonist suppresses inflammation and arthritis in mice.

Objective: To discover a novel peptoid antagonist that targets the interleukin-15 (IL-15) receptor and to evaluate its therapeutic efficacy in the treatment of inflammation and arthritis. Methods: A new compound (IFRA3, interleukin-15 receptor antagonist 3) was discovered using a unique on-bead two-colour combinatorial cell screening of a peptoid library. The interaction of IFRA3 with IL-15 receptor was assessed by in vitro pull-down and thermal shift assays. The efficacy of IFRA3 in treating inflammation and arthritis was evaluated in mouse models. Results: IFRA3Q1 (a tetrameric derivative of IFRA3) inhibited the activity of IL-15 and suppressed CTLL-2 cell proliferation (which depends on IL-15 activity). IFRA3Q1 exhibited strong in vivo anti-inflammatory activity in carrageenan-induced inflammation in mice. Furthermore, IFRA3Q1 inhibited collagen-induced arthritis in DBA/1J mice. Conclusion: By binding to and inhibiting the function of IL-15 receptor, IFRA3Q1 exhibited significant anti-arthritis activity. Our findings suggest that IFRA3Q1 represents a new paradigm for arthritis therapy by targeting IL-15 signalling.

Synthesis of 5-iodopyrrolo[1,2-a]quinolines and indolo[1,2-a]quinolines via iodine-mediated electrophilic and regioselective 6-endo-dig ring closure.

The endo-cyclic ring closure of 1-(2-(substituted ethynyl)phenyl)-1H-pyrroles 3a-t and 1-(2-(substituted ethynyl)phenyl)-H-indole 4a-o mediated by Lewis acid (I(2)) under mild conditions afforded substituted 5-iodopyrrolo[1,2-a]quinolines 5a-t and 5-iodoindolo[1,2-a]quinolines 6a-o in good to excellent yields. The reaction shows selective C-C bond formation on the more electrophilic alkynyl carbon, resulting in the regioselective 6-endo-dig-cyclized product. Iodo derivatives of pyrrolo- and indoloquinolines allow functional group diversification on the quinoline nucleus, which proves to be highly advantageous for structural and biological activity assessments.

Acute toxicity of textile dye Methylene blue on growth and metabolism of selected freshwater microalgae.

Microalgae are ecologically important species in aquatic ecosystems due to their role as primary producers. The inhibition of growth of microalgae due to dye pollution results in an upheaval in the trophic transfer of nutrients and energy in aquatic ecosystems. Therefore, this investigation aimed to evaluate the toxicity of a textile dye Methylene blue (MB) on two microalgae viz. Chlorella vulgaris and Spirulina platensis. An exposure of the unialgal populations of both the microalgae towards graded concentrations of the dye showed a concentration-dependent decrease in specific growth rate, pigment and protein content. In the toxicity study of 24 -96-h, following the OECD guidelines 201, the EC50 values of C. vulgaris and S. platensis ranged from 61.81 to 5.43 mg/L and 5.83 to 1.08 mg/L respectively revealing that S. platensis exhibited a higher level of susceptibility towards the dye as compared to C. vulgaris and the latter is more tolerant to the dye toxicity even at higher concentrations. The findings indicate that the response to dye is a species-specific phenomenon. Given the differences in the cell structure and enzymatic pathways in Spirulina platensis (a prokaryote) and Chlorella vulgaris (an eukaryote), the tolerance levels can differ. After 96-h exposure of C. vulgaris to MB (100 mg/L), the chlorophyll-a, b and carotenoid content were reduced 2.5, 5.96 and 3.57 times in comparison to control whereas in S. platensis exposure to MB (10 mg/L), the chlorophyll-a and carotenoid content were reduced 3.59 and 5.08 times in comparison to control. After 96-h exposure of C. vulgaris and S. platensis to the dye (20 mg/L), the protein content was found to be 4.34 and 2.75 times lower than the control. The protein content has decreased in accordance with the increase in dye concentration.

Anthropogenic pressure on mangrove ecosystems: Quantification and source identification of surficial and trapped debris.

The mangroves are well known for their ecological services and livelihood support to humankind. The mangrove forest is experiencing extreme pressure due to anthropogenic activities, mainly the debris pollution posing great harm to the mangrove ecosystems. The abundance, sources, and composition of surficial and trapped debris items in the six contiguous mangrove regions of Mumbai were studied by the belt-transect and quadrats method. A total number of 3526 surficial debris items (368 kg) were collected from twenty belt transects. The estimated mean surficial debris was 8.8 ± 3.4 pieces/m2 with a weight of 920 ± 317 g/m2. The mean trapped debris was 35 ± 10 pieces/tree and 2514 ± 758 g/tree. Plastic (62.4%) includes carry bags and food wrappers mainly. Shoreline/recreational activity-based debris (38.9%) and other items (32.7%) contributed significantly to the total debris pollution. The study provides evidence that the mangrove ecosystem acts as a natural filter and trap for coastal water debris. The trapped debris is a potential risk to the mangroves due to the barrier created on the canopy surface for the incident solar radiation utilized for photosynthesis. By conducting the cleaning programs in the mangrove vegetation stretches, the ecological disturbances to the mangrove ecosystems can be minimized. Further, the regular removal of trapped debris will complement coastal pollution management. The data generated from this study will help the policymakers and resource managers about the effective control and management of debris pollution in the mangroves region.

Adsorption-biodegradation coupled remediation process for the efficient removal of a textile dye through chemically functionalized sugarcane bagasse.

Textile dye effluents have many deleterious effects; therefore, it is essential to remove before releasing into waterbodies. This study developed a two-step process for decolorization of textile dye using sugarcane bagasse (SCB). The first step of the process involved functionalization of SCB with alginic acid and applying as packing material in column and assessing its performance for adsorptive removal of Drimarene red. The designed column showed 90% removal of the dye in dye-aqueous solution whereas 80% removal in dye-house wastewater. Adsorption capacity was increased at first 10 min and then gradually decreased with time. Breakthrough point was not achieved during the 60 min of experiment. Three non-equilibrium models were applied to understand the column bed properties. In the second step, the adsorbed dye molecules in SCB were degraded using an edible fungus Pleurotus sp. to obtain a dye-free nitrogen-rich bagasse. The fungus-treated SCB showed no residual toxicity and a considerable improvement in nitrogen content (from 0.14% to 0.62%) was noticed after the study of elemental profile. New design of the column bed, the processes of the chemical functionalization of the SCB, and bioremediation of dye treated bagasse through Pleurotus sp. offer a novel solution for efficient and safe disposal of textile dyes. PRACTITIONER POINTS: Two-step process for remediation of a textile dye using an agrowaste and Pleurotus sp. Chemical functionalization of an agrowaste for enhanced dye removal. New process of adsorption-fungal degradation for safe disposal of the dyes. Novel technology for a sustainable use of the agrowaste for environmental safety.