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1.
J Hazard Mater ; 424(Pt D): 127710, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34815126

RESUMO

Fimbristylis dichotoma, Ipomoea aquatica, Pluchea tomentosa and their co-plantation (consortium FIP) autonomously degrade Orange 3R. Consortium FIP showed 84% removal of Orange 3R within 48 h, which is a higher dye elimination rate than individual plant systems. Oxidoreductase enzymes like tyrosinase (76%), varatryal alcohol oxidase (85%), lignin peroxidase (150%), riboflavin reductase (151%), laccase (171%), NADH-DCIP reductase (11%) and azo reductase (241%) were expressed in consortia FIP during Orange 3R degradation. UV-vis spectroscopy, enzyme activities, HPTLC, FTIR and GC-MS confirmed mineralization of Orange 3R into its metabolites. Microscopic investigation of root tissue revealed the harsh effect of dye on root tissues. Toxicity assessment on the HepG2 cell line demonstrated the toxic nature of Orange 3R, which gets reduced after phyto-treatment with consortia FIP. Floating wetpark of consortia FIP was found more efficient for the treatment of industrial textile waste and accomplished 87%, 86%, 75%, 49% and 46% removal of COD, BOD, color, TSS and TDS of effluent.


Assuntos
Purificação da Água , Áreas Alagadas , Compostos Azo , Biodegradação Ambiental , Corantes , Resíduos Industriais , Indústria Têxtil , Têxteis , Águas Residuárias
2.
J Hazard Mater ; 418: 126349, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34118536

RESUMO

The potential of Iris pseudacorus and the associated periphytic biofilm for biodegradation of two common pharmaceutical contaminants (PCs) in urban wastewater was assessed individually and in consortium. An enhanced removal for sulfamethoxazole (SMX) was achieved in consortium (59%) compared to individual sets of I. pseudacorus (50%) and periphytic biofilm (7%) at concentration of 5 mg L-1. Conversely, individual sets of periphytic biofilm (77%) outperformed removal of doxylamine succinate (DOX) compared to individual sets of I. pseudacorus (59%) and consortium (67%) at concentration of 1 mg L-1. Enhanced relative abundance of microflora containing microalgae (Sellaphora, Achnanthidium), rhizobacteria (Acidibacter, Azoarcus, Thioalkalivibrio), and fungi (Serendipita) in periphytic biofilm was observed after treatment. SMX treatment for five days elevated cytochrome P450 enzymes' expressions, including aniline hydroxylase (48%) and aminopyrine N-demethylase (54%) in the periphytic biofilm. Nevertheless, I. pseudacorus showed 175% elevation of aniline hydroxylase along with other biotransformation enzymes, such as peroxidase (629%), glutathione S-transferase (514%), and dichloroindophenol reductase (840%). A floating bed phytoreactor planted with I. pseudacorus and the periphytic biofilm consortium removed 67% SMX and 72% DOX in secondary wastewater effluent. Thus, the implementation of this strategy in constructed wetland-based treatment could be beneficial for managing effluents containing PCs.


Assuntos
Gênero Iris , Preparações Farmacêuticas , Biofilmes , Nitrogênio/análise , Águas Residuárias
4.
Sci Total Environ ; 764: 144219, 2021 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-33421748

RESUMO

Acidification during anaerobic digestion (AD) due to organic overloading is one of the major reasons for process failures and decreased methane productivity in anaerobic digesters. Process failures can cause the anaerobic digesters to stall completely, prolong the digester recovery period, and inflict an increased operational cost on wastewater treatment plants and adverse impacts on the environment. This study investigated the efficacy of bioaugmentation by using acclimatized microbial consortium (AC) in recovering anaerobic digesters stalled due to acidosis. Overloading of digesters with food waste leachate (FWL) led to the accumulation of volatile fatty acids (11.30 g L-1) and a drop in pH (4.67), which resulted in process failure and a 22-fold decline in cumulative methane production compared to that in the initial phase. In the failure phase, the syntrophic and methanogenic activities of the anaerobic digester microbiota were disrupted by a significant decrease in the abundance of syntrophic populations such as Syntrophomonas, Syntrophorhabdus, Sedimentibacter, and Levilinea, and the phylum Euryarchaeota. Bioaugmentation of the failed digesters by adding AC along with the adjustment of pH resulted in the prompt recovery of methane productivity with a 15.7-fold higher yield than that in unaugmented control. The abundance of syntrophic bacteria Syntrophomonas and phylum Euryarchaeota significantly increased by 29- and 17-fold in the recovered digesters, respectively, which showed significant positive correlations with methane productivity. Methanosarcina and acetoclastic Methanosaeta played a major role in the recovery of the digesters; they were later replaced by hydrogenotrophic Methanoculleus. The increase in the abundance of genes associated with biomethanation contributed to digester recovery, according to the functional annotation of 16S rDNA amplicon data. Thus, bioaugmentation with AC could be a viable solution to recover digesters experiencing process failure due to organic overloading.


Assuntos
Metano , Eliminação de Resíduos , Anaerobiose , Reatores Biológicos , Alimentos , Consórcios Microbianos
5.
J Hazard Mater ; 401: 123404, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32659588

RESUMO

Pharmaceutical contaminants in environment induce unexpected effects on ecological systems and human; thus, development of efficient technologies for their removal is immensely necessary. In this study, biodegradation and metabolic fate of a frequently found pharmaceutical contaminant, doxylamine by Typha angustifolia and Ipomoea aquatica was investigated. Microbial community of the plant rhizosphere has been identified to understand the important roles of the functional microbes. The plants reduced 48-80.5 % of doxylamine through hydrolysis/dehydroxylation and carbonylation/decarbonylation. A constructed phytobed co-planted with T. angustifolia and I. aquatica removed 77.3 %, 100 %, 83.67 %, and 61.13 % of chemical oxygen demand, total nitrogen, total phosphorus, and doxylamine respectively from real wastewater. High-throughput sequencing of soil and rhizosphere indicated that the phyla Proteobacteria, Bacteroidetes, Firmicutes, Planctomycetes, Actinobacteria, and Cyanobacteria dominated the microbial communities of the phytobed. Current study has demonstrated the applicability of the developed phytobeds for the treatment of doxylamine from municipal wastewater and provide a comprehensive understanding of its metabolism through plant and its rhizospheric microbial communities.


Assuntos
Ipomoea , Microbiota , Typhaceae , Biodegradação Ambiental , Doxilamina , Humanos , Rizosfera , Microbiologia do Solo , Águas Residuárias
6.
J Hazard Mater ; 389: 122149, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32004845

RESUMO

Environmental contamination by benzophenone-3 has gained attention because of its frequent occurrence and adverse environmental impact. Studies investigating the toxicity and removal mechanisms, along with its degradation pathway in microalgae are still rare. In this study, the ecotoxicity of benzophenone-3 on Scenedesmus obliquus was assessed through dose-response test, risk quotient evaluation, and changes of microalgal biochemical characteristics and gene expression. The calculated risk quotients of benzophenone-3 were >1, implying its high environmental risk. Expression of the ATPF0C and Tas genes encoding ATP-synthase and oxidoreductase was significantly increased in S. obliquus after exposure to benzophenone-3, while that of Lhcb1 and HydA genes was reduced. When exposed to 0.1-3 mg L-1 benzophenone-3, 23-29 % removal was achieved by S. obliquus, which was induced by abiotic removal, bioadsorption, bioaccumulation and biodegradation. Metabolic fate analyses showed that biodegradation of benzophenone-3 was induced by hydroxylation, and methylation, forming less toxic intermediates according to the toxicity assessment of the identified products. This study provides a better understanding of the toxicity and metabolic mechanisms of benzophenone-3 in microalgae, demonstrating the potential application of microalgae in the remediation of benzophenone-3 contaminated wastewater.


Assuntos
Benzofenonas/metabolismo , Benzofenonas/toxicidade , Scenedesmus/efeitos dos fármacos , Scenedesmus/metabolismo , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade , Benzofenonas/química , Expressão Gênica/efeitos dos fármacos , Hidroxilação , Cinética , Metilação , Microalgas/efeitos dos fármacos , Microalgas/metabolismo , Fotossíntese/efeitos dos fármacos , Medição de Risco , Poluentes Químicos da Água/química
7.
Environ Sci Pollut Res Int ; 26(33): 34552-34561, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31650474

RESUMO

Pharmaceutical contamination in diverse water resources has been recognized as an emerging concern in environment because of its wide distribution and adverse effects on aquatic microorganisms and human health. Plant remediation with augmentation of microorganisms is a cost-effective and environmentally friendly approach toward an efficient treatment of pollutants, which can be easily applied in situ. (Bio)degradation of sulfamethazine (SMZ) by Iris pseudacorus, microalgal consortium, and plant-microalgal consortium was investigated. I. pseudacorus and microalgae could remove 63.5, and 25.8% of 1 mg SMZ L-1, respectively, whereas, the plant-microalgal consortium achieved 74% removal. The identified intermediates extracted after plant remediation indicated (bio)degradation of SMZ was through ring cleavage, hydroxylation, and dehydroxylation. Pigment content (total chlorophyll and carotenoid) of I. pseudacorus was significantly influenced by SMZ stress. A phytoreactor (20 L) constructed with I. pseudacorus achieved 30.0% and 71.3% removal of 1 mg SMZ L-1 from tap water and nutrient medium. This study has provided a better understanding of the metabolic mechanisms of SMZ in plants and showed the potential development of a plant-microalgal consortium as an advanced technology for treatment of these emerging contaminants. Graphical abstract.


Assuntos
Biodegradação Ambiental , Microalgas/metabolismo , Sulfametazina/metabolismo , Poluentes Químicos da Água/metabolismo , Clorofila/metabolismo , Humanos , Gênero Iris/crescimento & desenvolvimento
8.
Bioresour Technol ; 289: 121638, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31212174

RESUMO

Compositional variations in organic wastes influence microbial abundancy and syntrophy during anaerobic digestion (AD), impacting the normal performance of digesters for methanation. Investigation of the microbial dynamics during AD following augmentation with polysaccharidic wastes (PW) revealed the association of effective digester performance and methane yields with the microbial nexus. Dominance of the acidogenic saccharolytic genera, Prevotella, Eubacterium, and Lachnoclostridium, enhanced the utilization of carbohydrates (54%) in PW-augmented digesters. Spearman's rs correlation showed dynamic interspecies interactions among acetogenic syntrophs, and that of iron oxidizers/reducers with acetoclastic and hydrogenotrophic methanogens. Propionate oxidizers in Chloroflexi (i.e., Bellilinea, Levilinea, and Longilinea) exhibited positive associations with acetoclastic methanogens. Increase in the population of acetoclastic methanogens (Methanosaeta, 77% and Methanosarcina, 9%) accelerated the methanogenic activity of PW-augmented digesters by 7 times during the exponential phase, increasing the methane yield (75%) compared to the control. Thus, microbial syntrophy facilitated the effective methanation of PW during AD process.


Assuntos
Metano , Methanosarcina , Anaerobiose , Reatores Biológicos , Propionatos
9.
Trends Plant Sci ; 24(7): 611-624, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31085124

RESUMO

Microalgae hold the promise of an inexpensive and sustainable source of biofuels. The existing microalgal cultivation technologies need significant improvement to outcompete other biofuel sources such as terrestrial plants. Application of 'algomics' approaches under different abiotic stress conditions could be an effective strategy for optimization of microalgal growth and production of high-quality biofuels. In this review, we discuss the roles of omics in understanding genome structure and biocomponents metabolism in various microalgal species to optimize sustainable biofuel production. Application of individual and integrated omics revealed that genes and metabolic pathways of microalgae have been altered under multiple stress conditions, resulting in an increase in biocomponents, providing a research platform for expansion of genetic engineering studies in microalgal strains.


Assuntos
Microalgas , Biocombustíveis , Biotecnologia , Estresse Fisiológico
10.
Biotechnol Rep (Amst) ; 23: e00327, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30997348

RESUMO

Filamentous fungi perform tremendously in adsorption of dyes from polluted environment. In this study, Aspergillus niger LAG decolorized thiazole yellow G dye within 5 days. Scale up studies done revealed that maximum decolorization (98%) was achieved at a concentration (10 mg L-1), temperature (35 °C) and pH 6. The fungus exhibited significant inductions in laccase (71%) and lignin peroxidase (48%) respectively. Spectrometric analysis (UV-vis, HPLC and gas chromatography-mass spectrometry) was used in analyzing the degraded products of the dye. The GCMS analysis revealed the production of two metabolites; sodium 6-methyl-2-phenyl-1,3-benzothiazole-7-sulfonate and 2-phenyl-4,5-dihydro-1,3-thiazole after degradation of thiazole yellow G dye. A metabolic pathway of thiazole yellow G dye degradation by Aspergillus niger was proposed. Significant growth in plumule and radicle couple with an attendant increase in germination further confirmed the detoxified status of the dye after degradation.

11.
J Hazard Mater ; 374: 66-73, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30978632

RESUMO

Intensive use of atrazine in agriculture to increase crop productivity has resulted in pollution and consequently deteriorated the environment. Three isolated bacteria, Rhodococcus sp. BCH2 (RB), Bacillus sp. PDK1 (BP1) and Bacillus sp. PDK2 (BP2) possessing capability to degrade atrazine were used in different combinations (RB + BP1, RB + BP2, BP1 + BP2, RB + BP1 + BP2) to prepare a highly effective bacterial consortium which can significantly reduce the toxicity of atrazine. Cytotoxicity tests evaluated by MTT assay on HepG2 indicated significant decrease in the toxicity of atrazine by the consortium RB + BP1 + BP2 due to its effective degradation and formation of simpler and less/nontoxic metabolites compared to other combinations of consortia. A microcosm study was conducted to check the survivability of this consortium (RB + BP1 + BP2) in the presence of atrazine and indigenous soil microflora for four weeks. LC-Q-TOF/MS analysis revealed that RB + BP1 + BP2 could degrade atrazine to various simple metabolites in the microcosm. The cluster analysis of the DGGE patterns of the microcosm of control-soil, soil exposed to atrazine and soil augmented with consortium in the presence of atrazine (1000 mg kg-1) revealed a shift in microbial community of soil. The microbial dynamics studies suggested that the augmented bacteria were well-thrived with natural microflora during four weeks of exposure to atrazine.


Assuntos
Atrazina/metabolismo , Atrazina/toxicidade , Biodegradação Ambiental , Agricultura , Bacillus/metabolismo , Análise por Conglomerados , Células Hep G2 , Herbicidas/metabolismo , Herbicidas/toxicidade , Humanos , Microbiota , Filogenia , Rhodococcus/metabolismo , Solo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
12.
J Hazard Mater ; 371: 115-122, 2019 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-30849565

RESUMO

A combination of photocatalysis and biodegradation is a promising approach for the removal of xenobiotic organic compounds from wastewater, since photocatalysis cleaves the molecules into simpler intermediates that are later mineralized by microorganisms. Sequential photocatalytic and biological treatment (SPABT) consisting of ZnO as a photocatalyst and a microbial consortium (Galactomyces geotrichum and Brevibaccilus laterosporus) enhanced the degradation of a model textile dye, methyl red (MR). SPABT completely decolorized 500 mg MR/L within 4 h. Biotreatment alone required 6 h for 100% decolorization. A maximum of 70% decolorization was achieved with the photocatalytic treatment but reductions in COD and toxicity were not adequate. Significant elevated activities of enzymes, including azo reductase, laccase and veratryl alcohol oxidase, were observed in the microbial consortium after exposure of MR. The degradation pathway and products of MR varied with treatment applied. The persistent azo bond was cleaved by following photocatalytic treatment with the microbial biotreatment. Tests with Sorghum vulgare and Phaseolus mungo indicated the products obtained by SPABT were non-phytotoxic.


Assuntos
Compostos Azo/metabolismo , Biodegradação Ambiental , Processos Fotoquímicos , Catálise , Sistema Livre de Células , Enzimas/metabolismo , Consórcios Microbianos , Indústria Têxtil , Águas Residuárias/química
13.
Trends Biotechnol ; 37(8): 855-869, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30871798

RESUMO

'Higher' alcohols, which contain more than two carbons, have a higher boiling point, higher cetane number, and higher energy density than ethanol. Blends of biodiesel and higher alcohols can be used in internal combustion engines as next-generation biofuels without any modification and are minimally corrosive over extensive use. Producing higher alcohols from biomass involves fermenting and metabolizing amino acids. In this review, we describe the pathways and regulatory mechanisms involved in amino acid bioprocessing to produce higher alcohols and the effects of amino acid supplementation as a nitrogen source for higher alcohol production. We also discuss the most recent approaches to improve higher alcohol production via genetic engineering technologies for three microorganisms: Saccharomyces cerevisiae, Clostridium spp., and Escherichia coli.


Assuntos
Álcoois/metabolismo , Aminoácidos/metabolismo , Clostridium/metabolismo , Escherichia coli/metabolismo , Redes e Vias Metabólicas , Saccharomyces cerevisiae/metabolismo , Biotecnologia/métodos , Biotransformação , Clostridium/genética , Escherichia coli/genética , Saccharomyces cerevisiae/genética
14.
Chemosphere ; 225: 696-704, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30904757

RESUMO

Plants serve as appropriate markers of worldwide pollution because they are present in almost every corner of the globe and bioaccumulate xenobiotic chemicals from their environment. The potential of a semi-aquatic plant, Ipomoea aquatica, to uptake and metabolize sulfamethoxazole (SMX) was investigated in this study. I. aquatica exhibited 100% removal of 0.05 mg L-1 SMX from synthetic media within 30 h. The I. aquatica achieved 93, 77 and 72% removal of SMX at 0.2, 0.5 and 1 mg L-1, respectively, after 48 h. This indicated that removal efficiency of I. aquatica was deteriorating at high concentrations of SMX. The chlorophyll and carotenoid content of I. aquatica was insignificantly influenced by SMX irrespective of its high concentration. Similarly, scanning electron microscopy (SEM) showed that exposure to SMX had an insignificant impact on morphology of the plant organelles. The mechanisms of removal by I. aquatica were explored by evaluating contributions of bioadsorption, bioaccumulation and biodegradation. There was negligible adsorption of SMX to plant roots. Accumulation of SMX within plant roots and stems was not observed; however, I. aquatica accumulated 17% of SMX in leaves. Thus, the major mechanism of elimination of SMX was biodegradation, which accounted for 82% removal of SMX. Gas chromatography-mass spectrometry (GC-MS) confirmed that I. aquatica biodegraded SMX into simpler compounds, and generated 4-aminophenol as its final product. A laboratory scale phytoreactor was used to investigate the application of I. aquatica in a simulated system, where it achieved 49% removal of SMX (0.2 mg L-1) in 10 d.


Assuntos
Biodegradação Ambiental/efeitos dos fármacos , Ipomoea/metabolismo , Sulfametoxazol/metabolismo , Poluentes Químicos da Água/química , Água/química
15.
J Biosci Bioeng ; 127(3): 388-393, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30201527

RESUMO

Densitometric high performance thin layer chromatography (HPTLC) quantification method was developed to validate the decolorization/biotransformation of Disperse Orange ERL and dye mixture by lichen Parmelia sp. which release several colored compounds during decolorization process, hence unable to use colorimetric estimation. Percent decolorization of Disperse Orange ERL and dye mixture by lichen Parmelia sp. was observed when estimated using developed HPTLC method. Limit of detection and limit of quantification for both dyes in mixture were obtained as 0.3 and 1 µg/µl, respectively. Area of peak of control Disperse Orange ERL was reduced by 43% after 12 h, 71% after 48 h and upto 82% after 72 h of incubation. Precision and repeatability of data elucidated the % relative standard deviation less than 3 for all the values thus indicating statistically acceptable. Biodegradation of dye and mixture was confirmed with Fourier transform infrared spectroscopy analysis, i.e., altered fingerprinting spectral pattern.


Assuntos
Compostos Azo/metabolismo , Corantes/metabolismo , Líquens/metabolismo , Compostos Azo/isolamento & purificação , Biodegradação Ambiental , Biotransformação , Cor , Corantes/isolamento & purificação
16.
Bioresour Technol ; 272: 351-359, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30384210

RESUMO

Fats, oil and grease (FOG) are energy-dense wastes that substantially increase biomethane recovery. Shifts in the microbial community during anaerobic co-digestion of FOG was assessed to understand relationships between substrate digestion and microbial adaptations. Excessive addition of FOG inhibited the methanogenic activity during initial phase; however, it enhanced the ultimate methane production by 217% compared to the control. The dominance of Proteobacteria was decreased with a simultaneous increase in Firmicutes, Bacteriodetes, Synergistetes and Euryarchaeota during the co-digestion. A significant increase in Syntrophomonas (0.18-11%), Sporanaerobacter (0.14-6%) and Propionispira (0.02-19%) was observed during co-digestion, which substantiated their importance in acetogenesis. Among methanogenic Archaea, the dominance of Methanosaeta (94%) at the beginning of co-digestion was gradually replaced by Methanosarcina (0.52-95%). The absence/relatively low abundance of syntrophic acetate oxidizers and hydrogenotrophic methanogens, and dominance of acetoclastic methanogens suggested that methane generation during co-digestion of FOG was predominantly conducted through acetoclastic pathway led by Methanosarcina.


Assuntos
Gorduras/metabolismo , Metano/biossíntese , Methanosarcina/metabolismo , Óleos/metabolismo , Ácido Acético/metabolismo , Anaerobiose , Archaea/metabolismo , Bactérias/metabolismo , Reatores Biológicos/microbiologia
17.
Chemosphere ; 210: 968-976, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30208557

RESUMO

In situ phytoremediation of dyes from textile wastewater was carried out in a high rate transpiration system ridges (91.4 m × 1.0 m) cultivated independently with Tagetes patula, Aster amellus, Portulaca grandiflora and Gaillardia grandiflora which reduced American Dye Manufacturers Institute color value by 59, 50, 46 and 73%, respectively within 30 d compared to dye accumulated in unplanted ridges. Significant increase in microbial count and electric conductivity of soil was observed during phytoremediation. Reduction in the contents of macro (N, P, K and C), micro (B, Cu, Fe and Mn) elements and heavy metals (Cd, As, Pb and Cr) was observed in the soil from planted ridges due to phyto-treatment. Root tissues of these plants showed significant increase in the specific activities of oxido-reductive enzymes such as lignin peroxidase, laccase, veratryl alcohol oxidase, tyrosinase and azo reductase during decolorization of textile dyes from soil. Anatomical studies of plants roots revealed the occurrence of textile dyes in tissues and subsequent degradation. A minor decrease in plant growth was also observed. Overall surveillance suggests that the use of garden ornamental plants on the ridges of constructed wetland for the treatment of dyes from wastewater along with the consortia of soil microbial flora is a wise and aesthetically pleasant strategy.


Assuntos
Asteraceae/crescimento & desenvolvimento , Biodegradação Ambiental , Corantes/metabolismo , Desenvolvimento Vegetal/efeitos dos fármacos , Solo/química , Têxteis/análise , Águas Residuárias/química , Asteraceae/efeitos dos fármacos , Asteraceae/fisiologia , Corantes/farmacologia , Jardins , Metais Pesados/análise
18.
Ecotoxicol Environ Saf ; 161: 70-77, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29859410

RESUMO

This study explores the potential of Asparagus densiflorus to treat disperse Rubin GFL (RGFL) dye and a real textile effluent in constructed vertical subsurface flow (VSbF) phytoreactor; its field cultivation for soil remediation offers a real green and economic way of environmental management. A. densiflorus decolorized RGFL (40 gm L-1) up to 91% within 48 h. VSbF phytoreactor successfully reduced American dye manufacture institute (ADMI), BOD, COD, Total Dissolved Solids (TDS) and Total Suspended Solids (TSS) of real textile effluent by 65%, 61%, 66%, 48% and 66%, respectively within 6 d. Oxidoreductive enzymes such as laccase (138%), lignin peroxidase (129%), riboflavin reductase (111%) were significantly expressed during RGFL degradation in A. densiflorus roots, while effluent transformation caused noteworthy induction of enzymes like, tyrosinase (205%), laccase (178%), veratryl oxidase (52%). Based on enzyme activities, UV-vis spectroscopy, FTIR and GC-MS results; RGFL was proposed to be transformed to 4-amino-3- methylphenyl (hydroxy) oxoammonium and N, N-diethyl aniline. Anatomical study of the advanced root tissue of A. densiflorus exhibited the progressive dye accumulation and removal during phytoremediation. HepG2 cell line and phytotoxicity study demonstrated reduced toxicity of biotransformed RGFL and treated effluent by A. densiflorus, respectively. On field remediation study revealed a noteworthy removal (67%) from polluted soil within 30 d.


Assuntos
Asparagus/enzimologia , Compostos Azo/metabolismo , Corantes/metabolismo , Recuperação e Remediação Ambiental/métodos , Nitrilas/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Têxteis , Compostos de Amônio/metabolismo , Compostos de Anilina/metabolismo , Biodegradação Ambiental , Corantes/toxicidade , Produtos Agrícolas/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Células Hep G2 , Humanos , Resíduos Industriais , Lacase , Oxirredutases/metabolismo , Peroxidases , Raízes de Plantas/enzimologia , Indústria Têxtil , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo
19.
3 Biotech ; 8(3): 158, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29515964

RESUMO

In this study, we have described three steps to produce ethanol from Pogonatherum crinitum, which was derived after the treatment of textile wastewater. (a) Production of biomass: biomass samples collected from a hydroponic P. crinitum phytoreactor treating dye textile effluents and augmented with Ca-alginate immobilized growth-promoting bacterium, Bacillus pumilus strain PgJ (consortium phytoreactor), and waste sorghum husks were collected and dried. Compositional analysis of biomass (consortium phytoreactor) showed that the concentration of cellulose, hemicelluloses and lignin was 42, 30 and 17%, respectively, whereas the biomass samples without the growth-promoting bacterium (normal phytoreactor) was slightly lower, 40, 29 and 16%, respectively. (b) Hydrolysate (sugar) production: a crude sample of the fungus, Phanerochaete chrysosporium containing hydrolytic enzymes such as endoglucanase (53.25 U/ml), exoglucanase (8.38 U/ml), glucoamylase (115.04 U/ml), xylanase (83.88 U/ml), LiP (0.972 U/ml) and MnP (0.459 U/ml) was obtained, and added to consortium, normal and control phytoreactor derived biomass supplemented with Tween-20 (0.2% v/v). The hydrolysate of biomass from consortium phytoreactor produced maximum reducing sugar (0.93 g/l) than hydrolysates of normal phytoreactor biomass (0.82 g/l) and control phytoreactor biomass (0.79 g/l). FTIR and XRD analysis confirmed structural changes in treated biomass. (c) Ethanol production: the bioethanol produced from enzymatic hydrolysates of waste biomass of consortium and normal phytoreactor using Saccharomyces cerevisiae (KCTC 7296) was 42.2 and 39.4 g/l, respectively, while control phytoreactor biomass hydrolysate showed only 25.5 g/l. Thus, the amalgamation of phytoremediation and bioethanol production can be the truly environment-friendly way to eliminate the problem of textile dye along with bioenergy generation.

20.
Bioresour Technol ; 258: 365-375, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29501272

RESUMO

Microalgal biomass has received much attention as feedstock for biofuel production due to its capacity to accumulate a substantial amount of biocomponents (including lipid, carbohydrate, and protein), high growth rate, and environmental benefit. However, commercial realization of microalgal biofuel is a challenge due to its low biomass production and insufficient technology for complete utilization of biomass. Recently, advanced strategies have been explored to overcome the challenges of conventional approaches and to achieve maximum possible outcomes in terms of growth. These strategies include a combination of stress factors; co-culturing with other microorganisms; and addition of salts, flue gases, and phytohormones. This review summarizes the recent progress in the application of single and combined abiotic stress conditions to stimulate microalgal growth and its biocomponents. An innovative schematic model is presented of the biomass-energy conversion pathway that proposes the transformation of all potential biocomponents of microalgae into biofuels.


Assuntos
Microalgas , Biocombustíveis , Biomassa , Carboidratos , Lipídeos
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