Mitigation of air pollution by plants is a well-established phenomenon. Trees planted on the roadside are known to reduce particulate matter pollution by about 25%. In an urban ecosystem, especially in a metropolitan city such as Delhi, roadside trees are constantly exposed to air pollution. We, therefore, evaluated the effect of air pollution on a common Indian roadside tree, Neem (Azadirachta indica), and its associated microbes in areas with high and low levels of particulate matter (PM) pollution in Delhi. We hypothesized that alteration in the air quality index not only influences plant physiology but also its microbiome.A 100-fold increase in the number of epiphytic and 10–100 fold increase in endophytic colonies were found with 1.7 times increase in the level of pollutants. Trees in the polluted areas had an abundance of Salmonella, Proteus and Citrobacter, and showed increased secondary metabolites such as phenols and tannins as well as decreased chlorophyll and carotenoid. The number of unique microbes was positively correlated with increased primary metabolites.Our study thus indicates that, alteration in air quality affects the natural micro-environment of plants. These results may be utilized as sustainable tools for studying plant adaptations to the urban ecosystem.

Treated wastewater is an invaluable resource in meeting the growing demand of freshwater in tree crop irrigation in dry areas with additional benefits of land degradation reduction and biomass production. Seedlings of Acacia nilotica, Azadirachta indica, Eucalyptus camaldulensis, Prosopis cineraria, P. juliflora, Tamarix aphylla, Salvadora persica, S. oleoides and Tecomella undulata were planted and irrigated with bore-well (BW) and treated wastewater (WW) at ½ET (evapotranspiration) and ¾ET. Changes in soil properties and plant biomass allocation in different parts were assessed for species efficacy in phytoremediation of wastewater-contaminated soils and enhanced biomass yield. Irrigation enhanced soil pH, EC, SOC, available nutrients (greater in 0–30-cm soil layer than in 30–60-cm soil layer) and plant biomass. Wastewater irrigation had stronger effect in enhancing soil EC, SOC, NH₄-N and NO₃-N (3.50–76.92%), whereas increased quantity of irrigation showed stronger effects on PO₄-P, K, and root and shoot biomass (7.63–51.20%). High biomass in A. nilotica, A. indica, E. camaldulensis and P. juliflora plants was supported by increased root biomass to exploit increased level of water and nutrients. Indigenous S. oleoides, T. undulata, P. cineraria and S. persica showed greater potential of salts and nutrient absorption from the wastewater-contaminated soils. Moderate increase in pH and EC with simultaneous increase in SOC, nutrients and biomass exhibited beneficial use of wastewater in dryland afforestation. A. nilotica, A. indica, E. camaldulensis and P. juliflora were most efficient in utilising treated wastewater and beneficially can be utilised in urban afforestation and sustainable development of dry areas.

Sustainability in all applied fields particularly in textiles is to protect our globe, environment, and community, where green dyed products are playing their role. For the current study, Esfand (Peganum harmala) has been explored using a green isolation tool, i.e., ultrasonic (U.S.) rays, and applied onto fabric. Different dyeing parameters have been explored statistically through response surface methodology by employing temperature (50–80°C), time (25–65 min), extract volume (15–55 mL), salt (1–5 g/100 mL), and dye bath pH (4–7) through series of experiments. For developing new shades, green mordants such as elaichi, neem, turmeric, and zeera have been utilized. It has been found that exposure of 35 mL extract of 7 pH containing 3 g/100 mL of salt as exhausting agent to U.S. rays for 30 min for the dyeing of silk at 70°C for 45 min has given maximum color strength with reddish-yellow shades. Color characteristics obtained in the CIE Lab system reveal that 5% of turmeric as meta bio-mordant has given good quality reddish-yellow shades. It is found that U.S. rays have not only good potential to isolate colorant followed by dyeing of silk under reduced condition but also the application of bio-mordants have made the process more greener, sustainable, and cleaner.

Dyes and phenols are extensively used chemicals in petrochemicals, pharmaceuticals, textile, and paints industries. Due to high persistence, bioaccumulation, and toxicity, their removal from the environment is highly imperative by advanced techniques. Single metal oxide nanomaterials are generally associated with limitations of large bandgap (> 3eV) and charge recombination. Therefore, heterometallic oxides (HMOs) as CuFe₂O₄, CuMn₂O₄, and MnZn₂O₄ have been synthesized via green route by employing leaf extract of Azadirachta indica. XRD revealed the crystalline nature of HMOs nanospheres with particle size less than 100 nm. Subsequently, HMOs nanocatalysts were used as photocatalyst for removal of 3-amino phenols (3-AP) and eriochrome black T (EBT) from water under sunlight. Reaction parameters namely pollutant concentration (50–130 mgL⁻¹), catalyst dose (20–100 mg), and pH (3–11) were optimized in order to get best results. Substantial degradation (80–95%) of pollutants (50 mgL⁻¹) by HMOs (80 mg) was achieved at neutral pH under sunlight exposure. Highest removal by CuFe₂O₄ might be due to its high surface area (35.7 m²g⁻¹), low band gap (2.4 eV), larger particle stability (Zeta potential: -22.0 mV), and lower photoluminescence intensity. Sharp declines in curves were visually confirmed by color change and indicated for first-order kinetics of degradation with initial Langmuir adsorption. Spectrophotometric analysis revealed that half-life (t₁/₂) of 3-AP (0.9-1.7 h) and EBT (0.6-0.8 h) were significantly reduced. Faster degradation of EBT than 3-AP was because of less electronegative N-atom at the diazo group. Scavenger analysis indicated the presence of active radicals in photo-catalytic degradation of 3-AP and EBT. All HMOs have shown high reusability (n=8) which ensures their stability, sustainability, and efficiency. Overall, green synthesized HMOs nanoparticles with prominent surface characteristics offer a viable alternative photocatalyst for industrial applications.

Ecofriendly exploration of Arjun bark (Terminalia arjuna) is a herbal natural colorant for cotton dyeing. This is because the demand for natural dyes has been increased worldwide due to their therapeutic usage and other food, textiles, agriculture, engineering, and medical applications. Therefore, this study has been carried out due to the isolation of colorant from Arjun bark in an acidified methanolic medium after exposure to ultrasonic rays up to 60 min. Additionally, using bio-mordants, it has been found that the application of 10% of Zeera (Cuminum cyminum) extract as meta-bio-mordant, 3% of Ilaichi (Elettaria cardamomum) extract as meta-bio-mordant, and10 % of Harmal (Peganum harmala) and Neem (Azadirachta indica) extract as meta-bio-mordants has given excellent color strength. These bio-mordants have not only made the coloration process more eco-friendly, viable, and greener, but also improved color strength with various tonal effects from red to reddish brown shades. Thus, it has been found that ultrasonic treatment as an environment-friendly tool has not only enhanced the color strength of natural colorant isolated from Arjun bark onto the cotton fabric under mild conditions.

Improving digestibility, fermentation characteristics, and reducing greenhouse biogases to protect the environment without the use of synthetic materials is an important goal of modern-day farming and nutritionist. Plant extracts are capable of solving these. This is due to the digestive enzymes and the bioactive components capable of performing antimicrobial functions inherent in these plants. This study was aimed to investigate the effect of standard maize substrate treated with selected herbs and spices extracts on ruminal environmental biogas production and pressure during fermentation via biogas production technique. Herbs (Azadirachta indica leaves (T1), Moringa oleifera leaves (T2), Ocimum gratissimum leaves (T3) and spices (Allium sativum bulb (T4), Zingiber officinale rhizome (T5)) were harvested, air dried, and milled using standard procedures. Methanolic extracts of the herbs and spices were prepared and used as additives at different concentrations (50, 100, and 150 μL) to the maize substrate for in vitro biogas production. Data were analyzed using regression analysis. There were significant (P < 0.05) differences across all the treatments on the volume and pressure of biogas. The pressure and volume of biogas when compared with the levels tested showed differences (P < 0.05) across all the treatments for the prediction of volume from pressure of biogas. The pressure and volume of gas produced in vitro increased (P < 0.05) and biogases decreased (P < 0.05) by the substrate treated with herbs and spices but for the drum stick leaves which was similar for the levels of concentration tested. This means that the level tested had a pronounced mitigation effect on pressure of biogas and volume of biogas produced. It was concluded that the herb and spice extracts have the potential to improve rumen fermentation and reduce the production of biogases in ruminant diet.

Collagen is a promising candidate for food and pharmaceutical applications due to its excellent biocompatibility, low antigenicity, and controlled biodegradability; however, its heavy price restricts its utilization. Fish scales generated during the processing are generally regarded as waste material and an environmental pollutant, though they are a promising source of collagen. In the present study, Cirrhinus mrigala scales were demineralized and extracted for acid-soluble collagen (ASC) using acetic acid, with a collagen yield of 2.7%. UV–Vis spectra, SDS-PAGE, FTIR analyses, and amino acid composition confirmed the type I nature of the collagen extracted. The denaturation temperature of the collagen was found to be 30.09 °C using differential scanning calorimetry (DSC). The collagen was highly soluble at acidic pH and lower NaCl concentrations while its solubility was lowered in alkaline conditions and NaCl concentrations above 0.5 M. The collagen exhibited good emulsifying potential with an emulsion activity index (EAI) and emulsion stability index (ESI) of 21.49 ± 0.22 m² g⁻¹ and 15.67 ± 0.13 min, respectively. Owing to the good physicochemical characteristics of the extracted collagen, collagen-chitosan-neem extract (CCN) films were prepared subsequently which showed good antimicrobial activity against Bacillus subtilis NCIM 2635, Staphylococcus aureus NCIM 2654, Escherichia coli NCIM 2832, and Pseudomonas aeruginosa NCIM 5032, suggesting the potential of collagen in the development of antimicrobial films. These results demonstrate that the collagen from fish waste could be valorized and used effectively along with chitosan and neem extract for the synthesis of novel biodegradable films with antimicrobial efficacy.

Sodium chloride (NaCl) is commonly used as a curing/preservative agent for raw hides and skins in tanneries and is removed through a soaking process with total dissolved solids (TDS) and other organic pollutants in effluent, causing significant pollution load to the environment. Hence, the present study evaluated to apply dried neem leaf powder (DNL) as an additive to reduce the usage of salt in skin processing and preservation. To make certain of DNL antimicrobial properties, solvent extracts were performed against proteolytic bacteria isolated from raw skins. Initial characterization of DNL revealed the presence of bioactive compounds nimbolide and dehydro salannol and acetone extract with 16.9-mm, 10-mm and 8-mm zone of inhibition against Salmonella sp., E. coli sp. and Bacillus sp. identified using phenotypic conventional biochemical screening method. Further, skin curing experiments were carried out using four different treatments of DNL (10% 15%, 20% and 25% w/w) along with 15% w/w of conventional salt to obtain an optimum concentration for pilot-scale studies. Thus, the application of optimal DNL (15%) and salt (15%) resulted in no physical changes such as smell and hair slip and was taken for further studies for hydroxyproline activity, pollution load and organoleptic properties along compared with control 40% salt. DNL-aided salt less preservation of freshly flayed goat skins at ambient condition showed no hair slip or putrefaction during the preservation period with significant reduction of TDS (86%) and chloride (71%) in soak liquors compared to conventional salt preservation and enhanced organic load requiring additional treatment. However, the application of the organoleptic, physical and hydrothermal properties of resulting leathers produced from the DNL applied skins was on par with results of leather obtained from conventional salt. Thus, our results demonstrate DNL-aided salt less preservation method is able to reduce the amount of salt for preservation of goat skins significantly, leading to reduced salinity issues during leather processing.

Green vegetation enrichment is a cost-effective technique for reducing atmospheric pollution. Fifteen common tropical plant species were assessed for identifying their air pollution tolerance, anticipated performance, and metal accumulation capacity at Jharia Coalfield and Reference (JCF) site using Air Pollution Tolerance Index (APTI), Anticipated Performance Index (API), and Metal Accumulation Index (MAI). Metal accumulation efficiencies were observed to be highest for Ficus benghalensis L. (12.67mg/kg) and Ficus religiosa L. (10.71 mg/kg). The values of APTI were found to be highest at JCF for F. benghalensis (APTI: 25.21 ± 0.95), F. religiosa (APTI: 23.02 ± 0.21), Alstonia scholaris (L.) R. Br. (APTI: 18.50 ± 0.43), Mangifera indica L. (APTI: 16.88 ± 0.65), Azadirachta indica A. Juss. (APTI: 15.87 ± 0.21), and Moringa oleifera Lam. (APTI: 16.32 ± 0.66). F. benghalensis and F. religiosa were found to be excellent performers to mitigate air pollution at JCF as per their API score. Values of MAI, APTI, and API were observed to be lowest at reference sites for all the studied plant species due to absence of any air polluting sources. The findings revealed that air pollution played a significant impact in influencing the biochemical and physiological parameters of plants in a contaminated coal mining area. The species with the maximum MAI and APTI values might be employed in developing a green belt to minimize the levels of pollutants into the atmosphere.

Carbonized wood is a biofuel from cellulose pyrolysis with frequent smoke and life-threatening carcinogenic emissions. Carbon monoxide (CO), particulate matter (PM₂.₅), metalloids and trace elements from charcoals from six commonly used tropical timbers for carbonization in Donkorkrom (Ghana) were assessed. During combustion, Anogeissus leiocarpa charcoal emitted the least CO (4.28 ± 1.08 ppm) and PM₂.₅ (3.83 ± 1.57 μg/m³), while particulate matter was greatest for Erythrophleum ivorense (28.05 ± 3.08 ppm) and Azadirachta indica (27.67 ± 4.17 μg/m³) charcoals. Erythrophleum ivorense charcoal produced much lead (16.90 ± 0.33 ppm), arsenic (1.97 ± 0.10 ppm) and mercury (0.58 ± 0.003 ppm) but the least chromium (0.11 ± 0.01 ppm) and zinc (2.85 ± 0.05 ppm). Nickel was greatest for A. indica charcoal (0.71 ± 0.01 ppm) and least for Vitellaria paradoxa (0.07 ± 0.004 ppm). Trace elements ranged from 342.01 ± 2.54 ppm (A. indica) to 978.47 ± 1.80 ppm (V. paradoxa) for potassium and 1.74 ± 0.02% (V. paradoxa) to 2.24 ± 0.10% (A. indica) for sulphur. Besides A. leiocarpa charcoal, which ranked safest during combustion, the high PM₂.₅ and CO emissions make the other biofuels hazardous indoors. Kitchens need air filters to absorb these emissions together with the use of improved cook stoves. These carcinogenic metalloids would necessitate that their ashes be properly discarded without human contact. Yet, the charcoals would be much suitable as soil amendment bio-char for plant growth quality improvement.