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Phytoremediation is a promising green technology for the remediation of various industrial effluents. Notably, aquatic plants are widely applied to remove dyes and toxic metals from polluted environments. In the present study, the phytoremediation potency of aquatic macrophytes such as Pistia stratiotes L, Salvinia adnata Desv, and Hydrilla verticillata (L.f) Royle were assessed based on the removal capability of pollutants from dyeing effluent. Physicochemical characterizations were carried out for industrial wastewater collected from a cotton material dyeing unit located in the Karur District of Tamilnadu, India. The physicochemical characteristics of the dyeing effluent, such as color, odor, pH, total dissolved solids (TDS), alkalinity, acidity, chloride, sulfate, phosphate, nitrate, chemical oxygen demand (COD), fluoride, and toxic metal levels were determined. The core parameters such as total dissolved solid (TDS), chemical oxygen demand (COD), and chloride level were determined and found to be 6500 mg/L, 2400 mg/L, and 2050 mg/L, respectively, which exceeded the regulatory limit prescribed by the Central Pollution Control Board of India. The levels of toxic metals such as Hg, Ni, and Zn were under the acceptable concentration but Cr and Pb levels in the dyeing effluent were a little bit higher. The effluent was subjected to treatment with Pistia stratiotes L, Salvinia adnata Desv and Hydrilla verticillata (L.f) Royle separately. After the treatment, the toxic metal results were recorded as below detectable levels and the same results were obtained for all three aquatic plants samples used for treatment. Among the three plants, P. stratiotes L efficiently removed 86% of color, 66% of TDS, 77% of COD, and 61.33% of chloride. The variation in phytochemicals of the macrophytes was studied before and after treatment using GC&ndash, MS which revealed the reduction of ascorbic acid in the plant samples. The toxic effect of treated effluent was investigated by irrigating an ornamental plant, Impatiens balsamina L. The plant biomass P. stratiotes L obtained after the treatment process was subjected to manure production and its nutrient quality was proved, which can be applied as a soil conditioner. Among the aquatic plants, the results of P. stratiotes L indicated a higher remediation potential, which can be used as an ecologically benign method for treatment of industrial effluents and water bodies contaminated with dyeing effluents.

Endophytic microflora is a lesser approached source for nanoparticles synthesis. Myco-synthesis of iron nanoparticles was carried out using an endophytic fungi Penicillium oxalicum isolated from Tecomella undulata. Synthesized iron nanoparticles were characterized using different techniques. The UV–Visible absorption spectrum showed an absorption band at 300 ​nm, which is a characteristic of iron nanoparticles. The FTIR spectrum of iron nanoparticles showed absorption peaks ranging between 3430.70 cm−1–466.83 cm−1 range. SEM images showed 140 ​nm particles of spherical shape. AFM images indicated particle width and height being 3.9 ​nm and 100 ​nm respectively. The iron nanoparticles formed were used to study decolorization of methylene blue dye in the presence of H2O2. The dye was effectively decolourized up to 99.17% in a time interval of 6 ​h. Myco-synthesized nanoparticle mediated decolorization process confers a possibility of removal of toxic textile effluents in a sustainable way.

Efficiency of white-rot fungi—Stereum ostrea (S. ostrea) as a test culture and Phanerochaete chrysosporium (P. chrysosporium) as a reference culture in colour removal from a textile dye, Remazol brilliant blue-19 (RBB-19) in medium was compared in this study. S. ostrea was more efficient than P. chrysosporium in decoloration process. Different parameters pH, temperature, sources of carbon and nitrogen, stationary and shaking conditions were optimized for bleaching of dye by the fungal cultures. Optimal growth conditions for decoloration of dye by both cultures were pH 5.0, temperature 35 °C, glucose and fructose as best carbon source at 1 % level, peptone and urea as best nitrogen source and shaking conditions (150 rpm). Culture broth free of colour (99 % of decoloration) was achieved with S. ostrea as against 70 % decoloration by P. chrysosporium on 6th day of incubation. Adsorption of dye to fungal biomass as reflected by colour coating on biomass and participation of lignolytic enzymes in colour removal appeared to be mechanisms involved in decoloration process. The ability of both fungal cultures in removal of colour in effluents with dyes collected from silk saree-weaving cottage unit was tested. S. ostrea was also found to be more effective in colour removal from effluent. S. ostrea appears to be a promising culture for application of bioremediation in decoloration of dyes.

Potatoes are desirable source for polyphenol oxidase (PPO, EC 1.14.18.1) purification because this enzyme can be purified from the food industry waste such are potato peels from potato chips industry. This paper presents data concerning decolorization of 7 different, so far untested textile dyes and 3 real samples (industry effluents) by a partially purified PPO. Under optimized conditions 93-99.9% removal of dyes was achieved after 1 h using 424-1700 U ml(-1) of PPO, depending on dye. Optimum pH for decolorization process of all dyes was found to be 3.0. Potato PPO was capable of removing reactive dyes and textile dye effluents without requiring any mediator. Decolorization was accomplished via insoluble polymers formations that were separated by filtration. (C) 2012 Elsevier Ltd. All rights reserved.

Aims: To determine the adsorption of nickel and chromium in dye effluents using activated carbon prepared from groundnut shell and to determine the adsorption capacity at different contact time. Study Design: Adsorption capacity of the adsorbent. Place and Duration of Study: Department of Chemistry Federal University of Technology, Minna, Niger State, Nigeria, between April and November 2010. Methodology: Activated carbon was prepared from groundnut shell using two step processes with H2SO4 as an activating agent. Three different activated carbon was produced at different residual time of 5, 10 and 15 minutes which are GS/H2SO4/5 (AC1), GS/H2SO4/10 (AC2) and GS/H2SO4/15 (AC3). Chromium and nickel batch adsorption was carried out at various contact time (30 to 150 minutes). Results: The result indicated the maximum chromium and nickel adsorption at the contact time of 120 minutes and 150 minutes which implies that increase in contact time lead to increase in the adsorption of the heavy metals. Kinetic models including pseudo first-order, pseudo second-order and Elovich model were used to study the adsorption processes. Chromium and nickel adsorption could be best described by the pseudo second-order kinetic model. Conclusion: The study revealed that groundnut shell, a low cost adsorbent can be effectively used as a raw material for the preparation of activated carbon for the adsorption of chromium and nickel from dye effluent. Research Article American Chemical Science Journal, 2(1): 12-24, 2012 13

Among the industrial chemical wastes, the effluents of loom-dyeing industry raise great concern in recent times because of their diverse environmental hazards. A laboratory experiment was conducted to determine the phytotoxic effect of different loom-dye effluents on seed germination and early seedling growth of red amaranth (Amaranthus tricolor L.) in the Department of Agricultural Chemistry of Bangladesh Agricultural University, Mymensingh, during May to August, 2017. Results revealed that the physico-chemical parameters of loom-dye effluent such as pH, electrical conductivity (EC), total dissolved solids (TDS), sulphate, phosphate, sodium, potassium, iron, manganese and lead concentrations were relatively higher than the suggested range. On the other hand, the concentrations of calcium, zinc, copper and cadmium were relatively lower. Germination experiment of red amaranth were done in sterilized petridishes containing 0, 5, 10, 25, 50, 75 and 100% concentrations of three different types of untreated loom-dyeing effluents following completely randomized design. Three replications were used for each treatment. The germination energy and capacity, growth parameters like root and shoot length, relative toxicity, seedling vigour and phytotoxicity on seed germination of red amaranth in response to different loom-dyeing effluents at various concentrations were also calculated. There was a gradual lessening in the percentage of seed germination and seedling growth with increased concentration of effluents. Relative toxicity and phytotoxicity was extreme at 100% effluent concentration. Different growth parameters such as root and shoot lengths of seedlings was minimum at 100% and maximum at 5% dye effluent concentration. Overall results indicate that pink dye effluent was less toxic to the germination and early growth of red amaranth than violet and black dyes. For most of the growth parameters of red amaranth, the order of phytotoxicity among the loom-dye effluent was black > violet > pink. [Fundam Appl Agric 2018; 3(2.000): 480-490]