Jyoti P. Jadhav

Ecofriendly biodegradation and detoxification of Reactive Red 2 textile dye by newly isolated Pseudomonas sp. SUK1.

The aim of this work is to evaluate textile dyes degradation by novel bacterial strain isolated from the waste disposal sites of local textile industries. Detailed taxonomic studies identified the organisms as Pseudomonas species and designated as strain Pseudomonas sp. SUK1. The isolate was able to decolorize sulfonated azo dye (Reactive Red 2) in a wide range (up to 5 g l(-1)), at temperature 30 degrees C, and pH range 6.2-7.5 in static condition. This isolate also showed decolorization of the media containing a mixture of dyes. Measurements of COD were done at regular intervals to have an idea of mineralization, showing 52% reduction in the COD within 24h. Induction in the activity of lignin peroxidase and azoreductase was observed during decolorization of Reactive Red 2 in the batch culture, which represented their role in degradation. The biodegradation was monitored by UV-vis, IR spectroscopy, HPLC. The final product, 2-naphthol was characterized by GC-mass spectroscopy. The phytotoxicity study revealed the degradation of Reactive Red 2 into non-toxic product by Pseudomonas sp. SUK1.

Biotransformation of malachite green by Saccharomyces cerevisiae MTCC 463

In recent years, use of microbial biomass for decolourization of textile industry wastewater is becoming a promising alternative in which some bacteria and fungi are used to replace present treatment processes. Saccharomyces cerevisiae MTCC 463 decolourized the triphenylmethane dyes (malachite green, cotton blue, methyl violet and crystal violet) by biosorption, showing different decolourization patterns. However, malachite green decolourized by biosorption at the initial stage and further biodegradation occurred, about 85% in plain distilled water within 7 h, and about 95.5% in 5% glucose medium within 4 h, under aerobic conditions and at room temperature. Decolourization of malachite green depends on various conditions, such as concentration of dye, concentration of cells, composition of medium and agitation. HPLC, UV‐VIS, FTIR and TLC analysis of samples extracted with ethyl acetate from decolourized culture flasks confirmed the biodegradation of malachite green into several metabolites. A study of the enzymes responsible for the biodegradation of malachite green in the control and cells obtained after decolourization showed the activities of laccase, lignin peroxidase, NADH‐DCIP reductase, malachite green reductase and aminopyrine N‐demethylase in control cells. A significant increase in the activities of NADH‐DCIP reductase and MG reductase was observed in the cells obtained after decolourization, indicating a major involvement of reductases in malachite green degradation. Copyright

Evaluation of the efficacy of a bacterial consortium for the removal of color, reduction of heavy metals, and toxicity from textile dye effluent.

A microbial consortium DAS consisting three bacterial sp. originally obtained from dye contaminated sites of Solapur, India was selected because it was capable of decolorizing textile effluent and dye faster than the individual bacteria under static conditions. Identification of the isolates by 16S rRNA techniques revealed the isolates to be Pseudomonas species. The concerted metabolic activity of these isolates led to complete decolorization of textile effluent as well as Reactive Orange 16 (100 mg l(-1)) within 48-h at pH 7 and 30 degrees C. Studies involving Reactive Orange 16 (RO16) dye were carried with the bacterial consortium DAS to elucidate the mechanism of biodegradation. Induction of the laccase and reductase enzyme during RO16 decolorization indicated their role in biodegradation. The biodegradation of RO16 was monitored by using IR spectroscopy, HPLC and GC-MS analysis. Cytotoxicity, genotoxicity and phytotoxicity studies carried out before and after decolorization of the textile effluent revealed the nontoxic nature of the biotreated sample.

Textile dye degradation by bacterial consortium and subsequent toxicological analysis of dye and dye metabolites using cytotoxicity, genotoxicity and oxidative stress studies.

The present study aims to evaluate Red HE3B degrading potential of developed microbial consortium SDS using two bacterial cultures viz. Providencia sp. SDS (PS) and Pseudomonas aeuroginosa strain BCH (PA) originally isolated from dye contaminated soil. Consortium was found to be much faster for decolorization and degradation of Red HE3B compared to the individual bacterial strain. The intensive metabolic activity of these strains led to 100% decolorization of Red HE3B (50 mg l(-1)) with in 1h. Significant induction of various dye decolorizing enzymes viz. veratryl alcohol oxidase, laccase, azoreductase and DCIP reductase compared to control, point out towards their involvement in overall decolorization and degradation process. Analytical studies like HPLC, FTIR and GC-MS were used to scrutinize the biodegradation process. Toxicological studies before and after microbial treatment was studied with respect to cytotoxicity, genotoxicity, oxidative stress, antioxidant enzyme status, protein oxidation and lipid peroxidation analysis using root cells of Allium cepa. Toxicity analysis with A. cepa signifies that dye Red HE3B exerts oxidative stress and subsequently toxic effect on the root cells where as biodegradation metabolites of the dye are relatively less toxic in nature. Phytotoxicity studies also indicated that microbial treatment favors detoxification of Red HE3B.

Biodegradation of triphenylmethane dye cotton blue by Penicillium ochrochloron MTCC 517.

Triphenylmethane dyes belong to the most important group of synthetic colorants and are used extensively in the textile industries for dying cotton, wool, silk, nylon, etc. They are generally considered as the xenobiotic compounds, which are very recalcitrant to biodegradation. Penicillium ochrochloron decolorizes cotton blue (50 mg l(-1)) within 2.5 h under static condition at pH 6.5 and temperature 25 degrees C. TLC, FTIR and HPLC analysis confirms biodegradation of cotton blue. FTIR spectroscopy and GC-MS analysis indicated sulphonamide and triphenylmethane as the final products of cotton blue degradation. The pH, temperature and maturity of biomass affected the rate of decolorization. Presence of lignin peroxidase, tyrosinase and aminopyrine N-demethylase activities in the cell homogenate as well as increase in the extracellular activity of lignin peroxidase suggests the role of these enzymes in the decolorization process. The phytotoxicity and microbial toxicity studies of extracted metabolites suggest the less toxic nature of them.

Biotechnological strategies for phytoremediation of the sulfonated azo dye Direct Red 5B using Blumea malcolmii Hook

Tissue cultured shrub plants of Blumea malcolmii were found to decolorize Malachite green, Red HE8B, Methyl orange, Reactive Red 2 and Direct Red 5B at 20 mg L(-1) concentration to varying extent within three days. A significant induction in the activities of lignin peroxidase, tyrosinase, DCIP (2,6-dichlorophenol-indophenol) reductase, azoreductase and riboflavin reductase in the roots was observed during the decolorization of Direct Red 5B, which indicated their crucial role in the metabolism of the dye. HPLC (High Performance Liquid Chromatography) and FTIR (Fourier Transform Infrared Spectroscopy) analysis of the samples before and after decolorization of the dye confirmed the phytotransformation of Direct Red 5B. The GC-MS (Gas Chromatography Mass Spectroscopy) analysis of the products led us to the identification of three metabolites formed after phytotransformation of the dye as 4-(4-amino-phenylazo)-benzene sulfonic acid, 3-amino-7-carboxyamino-4-hydroxy-naphthalene-2-sulfonic acid and 7-carboxyamino-naphthalene-2-sulfonic acid.

Ecofriendly degradation, decolorization and detoxification of textile effluent by a developed bacterial consortium

Present study illustrates the effectual decolorization and degradation of the textile effluent using a developed bacterial consortium SDS, consisted of bacterial species Providencia sp. SDS and Pseudomonas aeuroginosa strain BCH, originally isolated from dye contaminated soil. The intensive metabolic activity of the consortium SDS led to complete decolorization of textile effluent within 20 h at pH 7 and temperature 30°C. Significant induction in the activities of veratryl alcohol oxidase, laccase, azoreductase and DCIP reductase were observed during decolorization, which indicates their involvement in decolorization and degradation process. The decolorization and biodegradation was monitored using UV-vis spectroscopy, IR spectroscopy, HPLC and HPTLC analysis. Toxicological analysis of effluent before and after treatment was performed using classical Allium cepa test. Investigations of various toxicological parameters viz, oxidative stress response, cytotoxicity, genotoxicity and phytotoxicity, collectively concludes that, the toxicity of effluent reduces significantly after treatment with consortium SDS.

POTENTIAL OF BRASSICA JUNCEA IN ORDER TO TREAT TEXTILE—EFFLUENT—CONTAMINATED SITES

Three plant species (Brassica juncea, Sorghum vulgare, and Phaseolus mungo) of different agronomic consequence were evaluated for the decolorization of the dyes from textile effluent. B. juncea, S. vulgare, and P. mungo showed textile effluent decolorization up to 79, 57, and 53%, respectively. A significant decrease in shoot and root height, but no significant injury, was observed in the case of P. mungo and S. vulgare. B. juncea (Indian mustard), the most tolerant and more effective metals accumulator than other tested agricultural plant species, showed enhanced growth with respect to the height of the shoot and root, 129 and 178%, respectively, when grown using original textile effluent. Textile effluent induced intracellular nicotinamide adenine dinucleotide reduced (NADH)–dichlorophenol indophenol reductase significantly in the case of S. vulgare and B. juncea with 209 and 194%, respectively. The extracellular riboflavin reductase activity was induced by 223% in the case of P. mungo as compared to control plants. Significant induction of intracellular laccase (266%) was observed in the case of B. juncea, indicating their crucial role for a potential metabolism and further degradation of the textile effluent. The metabolites were identified as napthalenesufamide (m/z 372) and 2-amino-4, 6-dichlorotriazine (m/z 167), when B. juncea was used to degrade a model dye, Reactive red 2.

Production of polyhydroxyhexadecanoic acid by using waste biomass of Sphingobacterium sp. ATM generated after degradation of textile dye Direct Red 5B.

The degradation of textile effluent using microorganisms has been studied extensively, but disposal of generated biomass after dye degradation is a serious problem. The isolated Sphingobacterium sp. ATM was found to decolorize dye Direct Red 5B (DR5B) and simultaneously it produced polyhydroxyhexadecanoic acid (PHD). The organism decolorized DR5B at 500mgl(-1) concentration within 24h of dye addition and gave optimum production of PHD. The medium contains carbon source as a molasses which was found to be more significant within all carbon sources used. The Nuclear Magnetic Resonance spectroscopy (NMR), Fourier Transform Infrared spectroscopy (FTIR) and Gas Chromatography-Mass Spectroscopy (GC-MS) characterization of polyhydroxyalkanoates obtained revealed the compound as a polyhydroxyhexadecanoic acid. The activity of PHA synthase was found more at 24h after dye addition. The enzymes responsible for dye degradation include veratrol oxidase, laccase, DCIP (2,6-dichlorophenol-indophenol) reductase, riboflavin reductase and azo reductase was found to be induced during decolorization process. The FTIR analysis of samples before and after decolorization of dye confirmed the biotransformation of DR5B. The GC-MS analysis of product obtained led to the identification of two metabolites after biotransformation of dye as p-amino benzenesulfonic acid and naphthalene-1-ol.

Opuntia and other cacti: applications and biotechnological insights.

The cactus family is unusual among tropical plants. Cacti, known for their minimum water requirement, have been grown extensively in arid lands, for food, feeds and medicinal and therapeutic uses.Several food products have cacti as a main ingredient. Cacti biochemical analysis substantiate the high nutritive value of this plant family. Tissue cultures, including micropropagation, callus, and cell suspension cultures have been established for numerous cacti species. Genetic engineering has opened opportunities for gene isolation and integration of genes from other sources for cacti improvement. Cacti might be a store house of stress tolerant genes for other crops. Since cacti can be cultivated easily with minimum agriculture inputs, they hold great potential for cultivation and farming on degraded lands and for at least partial remediation of degraded lands. The present review outlines some of the older and more recent research on the properties and applications for Opuntia and other cacti especially as they might apply towards agricultural sustainability.