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1.
Environ Pollut ; 292(Pt A): 118267, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601036

RESUMO

Distillery sludge is a major source of aquatic pollution, but little is known about their microbial community and their association with the organic and metal pollutants. Sugarcane molasses-based distillery is an important industry in India, although the waste is usually treated prior to disposal, the treatment is often inadequate. The adverse effects of the organic and metal pollutants in sugarcane molasses-based distillery sludge on the microbial biodiversity and abundance in the disposal site have not been elucidated. This study aims to address this gap of knowledge. Samples were collected from the discharge point, 1 and 2 km downstream (D1, D2, and D3, respectively) of a sugarcane distillery in Uttar Pradesh, India, and their physico-chemical properties characterised. Using QIIME, taxonomic assignment for the V3 and V4 hypervariable regions of 16 S rRNA was performed. The phyla Proteobacteria (28-39%), Firmicutes (20-28%), Bacteriodetes (9-10%), Actinobacteria (5-10%), Tenericutes (1-9%) and Patescibacteria (2%) were the predominant bacteria in all three sites. Euryechaeota, were detected in sites D1 and D2 (1-2%) but absent in D3. Spirochaetes (5%), Sinergistetes (2%) and Cloacimonetes (1%) were only detected in samples from site D1. Shannon, Simpson, Chao1, and Observed-species indices indicated that site D1 (10.18, 0.0013, 36706.55 and 45653.84, respectively) has higher bacterial diversity and richness than D2 (6.66, 0.0001, 25987.71 and 49655.89, respectively) and D3 (8.31, 0.002, 30345.53 and 30654.88, respectively), suggesting the organic and metal pollutants provided the stressors to favour the survival of microbial community that can biodegrade and detoxify them in the distillery sludge. This study confirmed that the treatment of the distillery waste was not sufficiently effective and provided new metagenomic information on its impact on the surrounding microbial community. It also offered new insights into potential bioremediation candidates.


Assuntos
Poluentes Ambientais , Microbiota , Saccharum , Melaço , Esgotos , Eliminação de Resíduos Líquidos , Águas Residuárias
2.
Environ Pollut ; 292(Pt B): 118342, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34653589

RESUMO

Restoring an environment contaminated with persistent organic pollutants (POPs) is highly challenging. Biodegradation by biofilm-forming bacteria through quorum sensing (QS) is a promising treatment process to remove these pollutants and promotes eco-restoration. QS plays an important role in biofilm formation, solubilization, and biotransformation of pollutants. QS is a density-based communication between microbial cells via signalling molecules, which coordinates specific characters and helps bacteria to acclimatize against stress conditions. Genetic diversification of a biofilm offers excellent opportunities for horizontal gene transfer, improves resistance against stress, and provides a suitable environment for the metabolism of POPs. To develop this technology in industrial scale, it is important to understand the fundamentals and ubiquitous nature of QS bacteria and appreciate the role of QS in the degradation of POPs. Currently, there are knowledge gaps regarding the environmental niche, abundance, and population of QS bacteria in wastewater treatment systems. This review aims to present up-to-date and state-of-the-art information on the roles of QS and QS-mediated strategies in industrial waste treatment including biological treatments (such as activated sludge), highlighting their potentials using examples from the pulp and paper mill industry, hydrocarbon remediation and phytoremediation. The information will help to provide a throughout understanding of the potential of QS to degrade POPs and advance the use of this technology. Current knowledge of QS strategies is limited to laboratory studies, full-scale applications remain challenging and more research is need to explore QS gene expression and test in full-scale reactors for wastewater treatment.


Assuntos
Resíduos Industriais , Percepção de Quorum , Biofilmes , Poluentes Orgânicos Persistentes , Esgotos
3.
Bioresour Technol ; 338: 125518, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34273628

RESUMO

This study aimed to detoxify and degrade the organometallic pollutants from distillery wastewater by using an autochthonous microbial community via biostimulation and bioaugmentation process. Results revealed that the wastewater contained high concentrations of the metals i.e. Fe-2403; Zn-210.15; Cr- 22.825; Cu-73.62; Mg-27.30; Ni-14.425; and Pb-17.33 (mg L-1). The biostimulation and bioaugmentation process resulted from a substantial reduction (50-70%) in the pollution load. Scanning electron microscopy analysis showed bacterial community and their relationship with complex organometallic pollutants during the chemical reactions. The major identified organic pollutants in the control (untreated) samples were acetic acid, Oxo-,trimethylsilyl ester [CAS], Hydrocinnamic acid, p-[Trimethylsiloxy]-trimethylsilyl ester and tetradecanoic acid, trimethylsilyl ester [CAS] while some new metabolic products were generated as a by-product in bioaugmentation process. Therefore, the study showed that biostimulation and bioaugmentation were successful bioremediation strategies for the detoxification of distillery wastewater and restoration of organometallic polluted sites.


Assuntos
Poluentes Ambientais , Poluentes do Solo , Bactérias , Biodegradação Ambiental , Águas Residuárias
4.
J Environ Manage ; 296: 113182, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34229138

RESUMO

A field experiment was conducted during 2007-2019 under various rabi (winter) crops (viz., wheat, maize, barley and mustard) on a Vertisol in sub-tropical Indo-Gangetic Plains (IGP) with different tillage systems to assess energy indices, greenhouse gas (GHG) emission and carbon sustainability index in assured irrigated fields. The tillage systems were: no tillage sown by a zero till drill (NT), no tillage with retention of previous crop residues at 6 t ha-1 and sowing by a happy turbo seeder (HT), and conventional tillage (CT) where sowing was performed by a multi-crop zero till drill after twice harrowing + twice tilling + once rotavator operations. Significantly higher input energy was observed in wheat followed by maize, barley and mustard. Among tillage systems, CT plots consumed higher input energy that was about 20, 21 to 22, 25 to 26 and 20-22% higher than HT and NT in wheat, maize, barley and mustard, respectively. However, output energy and energy use efficiency were highest in HT. The total GHG emission (kg CO2 equivalent ha-1) was highest in wheat (2,351) followed by maize (2,274), barley (1,859) and mustard (1,652). Among tillage systems, CT produced about 31-34%, 33-34%, 37-40% and 28-30% higher GHG emission than HT and NT under wheat, maize, barley and mustard, respectively. The CT plots had lower carbon sustainability index and carbon efficiency than ZT and HT in all crops. In short, HT recorded significantly higher energy use efficiency and lower global warming potential (GWP) than CT in all crops. Thus, HT could be a promising agro-technique for production of rabi crops in the IGP. Among rabi crops, barley production was energy efficient and had less GWP. In rabi crop production, the highest energy sources was mineral fertilizer use (25-49%) and second highest source was irrigation water (14-44%). These can be substituted with use of the organic sources of fertilizers and application of solar and wind power in irrigation, respectively.


Assuntos
Aquecimento Global , Óxido Nitroso , Agricultura , Produtos Agrícolas , Óxido Nitroso/análise , Solo
5.
Bioresour Technol ; 337: 125331, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34120065

RESUMO

Anaerobic digestion (AD) of acidic kitchen waste (KW) streams is found to be unstable and leads to poor overall efficiency. This study assessed the effect of pongamia de-oiled cake addition on KW-AD. High acidic KW (pH: 2.00-5.00), medium acidic KW (pH: 5.00-7.00) and low alkaline KW (pH: 7.00-8.00) fed into digesters I, II and III at 10% total solids (TS) achieved biogas yields of 177.82 ± 19.30, 216.57 ± 7.42 and 280.45 ± 2.55 L/kg VS. d, respectively. Maximum synergistic effect of pongamia de-oiled cake was observed in digester I with increased methane production of 46.04% and volatile solids reduction of 11.18%. The principal component analysis and kinetic evaluation revealed that pongamia de-oiled cake addition had a positive effect on the AD parameters in all digesters. With energy efficiencies exceeded 96% in all the digesters, the study proposes the addition of protein-rich additives for KW-AD stabilization.


Assuntos
Biocombustíveis , Metano , Anaerobiose , Reatores Biológicos , Alimentos
7.
Bioresour Technol ; 333: 125192, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33915458

RESUMO

This study aimed to assess the phytoremediation potential of Ricinus communis L. for heavy metals remediation via rhizospheric bacterial activities for distillery wastewater detoxification and management. Results revealed that distillery wastewater contained high levels of metals and other physico-chemical pollution parameters that could cause environmental pollution and aquatic toxicity. The identified bacterium produced several plant growth-promoting compounds including siderophores, ligninolytic enzymes, and indole acetic acid that resulted in nutrient enhancement and improved mineralization of metals in the plants during stress conditions. The bioconcentration factor (BCF) of all the metals examined were > 1, which showed that these metals are accumulating in the root, shoot, and leaves of Ricinus communis L. Most of the metals are stablised in the roots but Pb, Cd and Zn were translocated more to the shoorts (TC>1). The ability of Ricinus communis L. to grow in metals-containing distillery wastewater and reduce heavy metals and organic contaminants suggests that it can be used to provide an effective treatment of distillery wastewater. The use of Ricinus communis L. is an eco-friendly tool for the reduction of organometallic contamination and protecting agricultural land.


Assuntos
Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Metais Pesados/análise , Raízes de Plantas/química , Ricinus , Poluentes do Solo/análise , Águas Residuárias
8.
Chemosphere ; 273: 129693, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33524742

RESUMO

Anthropogenically impacted surface waters are an important reservoir for multidrug-resistant bacteria and antibiotic-resistant genes. The present study aimed at MDR, ESBL, AmpC, efflux genes, and heavy metals resistance genes (HMRGs) in bacterial isolates from four Indian rivers belonging to different geo-climatic zones, by estimating the mode of resistance transmission exhibited by the resistant isolates. A total 71.27% isolates exhibited MDR trait, showing maximum resistance towards ß-lactams (P = 66.49%; AMX = 59.04%), lincosamides (CD = 65.96%), glycopeptides (VAN = 25.19%; TEI = 56.91%), cephalosporins (CF = 53.72%; CXM = 30.32%) sulphonamide (COT = 43.62%; TRIM = 12.77%), followed by macrolide and tetracycline. The dfrA1 and dfrB genes were detected in total 37.5% isolates whereas; dfrA1 genes were detected in 33.34%. The sul1 gene was detected in 9.76% and sul2 gene was detected in 2.44% isolates. A total of 69.40% MDR integron positive isolates were detected with intI1and intI2 detected at 89.25% and 1.07%, respectively; encoding class 1 and class 2 integron-integrase. ESBL production was confirmed in 73.13% isolates that harboured the genes blaTEM (96.84%), blaSHV (27.37%), blaOXA (13.68%) and blaCTXM (18.95%) while the frequency of HMRGs; 52.24% (zntB), 33.58% (chrA), and 6.72% (cadD). Efflux activity was confirmed in 96.26% isolates that harbored the genes acrA (93.02%), tolC (88.37%), and acrB (86.04%). AmpC (plasmid-mediated) was detected in 20.9% of the riverine isolates. Detection of such hidden molecular modes of antibiotic resistance in the rivers is alarming that requires urgent and stringent measures to control the resistance threats.


Assuntos
Antibacterianos , Integrons , Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana , Plasmídeos , beta-Lactamases/genética , beta-Lactamas
9.
Environ Geochem Health ; 43(5): 2143-2164, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33400008

RESUMO

Discharged pulp and paper mill wastewater (PPMW) were collected near M/s K. R. pulp and papers Limited, Shahjahanpur, India. Chemical analysis of the wastewater showed high BOD (3653-4180 mg L-1) and COD (17,890-19100 mg L-1) values from two different sampling sites. The levels of total phenol were in the range of 389-432 mg L-1; nitrogen (125-234 mg L-1), sulfate (1926-2098 mg L-1), chloride (3.12-5.43 mg L-1) and lignin (38,950-39,000 mg L-1) along with various heavy metals (Fe, 87-79; Zn, 34-22; Cu, 3.28-2.57; Cd, 1.90-0.36; Ni, 6-5, and Pb, 41.23-36.54 mg L-1) were above the permissible limits recommended by the CPCB and the USEPA. The BOD/COD ratio was < 0.2 which indicated very low biodegradability of the organic matters present in the effluent. The organometallic complex generated from the pulp and paper industry persists in the environment and might be toxic to aquatic organisms. The organic polymers, lignin, metals and ions present in the PPMW were characterized using SEM, EDAX, FTIR, and UV-VIS spectroscopy. The major pollutants detected in the discharged PPMW included nonacosane, heptacosane, octadecanoic acid, hexadecane, and 6-benzamide- 3- [2- [1-(phenylmethyl)-4-piperidinyl] ethyl]-1, 2-benzisoxazole, as well as a group of plant fatty acids classified as EDCs, and mutagenic pollutants. The cytotoxic and androgenic properties of these complex organics were examined. The seed germination test with Phaseolus mungo and cytotoxicity test with Allium cepa showed that at > 20% concentration of PPMW, α-amylase production was inhibited and chromosomal segregation at metaphase and anaphase during cell division was disturbed, which resulted in c-mitosis, sticky chromosomes, and laggard chromosomes. In addition, SEM of the root of A. cepa showed fissures and fractured tissues of the root cap, probably due to the inhibition of auxins that were responsible for root cap formation. The findings indicated A. cepa as a good test model for examining the DNA damage and cytotoxicity by PPMW, and the discharged effluent should be treated at a tertiary stage for environmental protection.


Assuntos
Cebolas/efeitos dos fármacos , Testes de Toxicidade/métodos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Germinação/efeitos dos fármacos , Índia , Lignina/análise , Metais Pesados/análise , Nitrogênio/análise , Fenóis/análise , Sementes/efeitos dos fármacos , Solventes/química , Vigna/efeitos dos fármacos , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química
10.
Bioresour Technol ; 324: 124681, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33454444

RESUMO

This work aimed to study the profiling and efficiency of microbial communities and their abundance in the pulp and paper industry wastewater, which contained toxic metals, high biological oxygen demands, chemical oxygen demand, and ions contents. Sequence alignment of the 16S rRNA V3-V4 variable region zone with the Illumina MiSeq framework revealed 25356 operating taxonomical units (OTUs) derived from the wastewater sample. The major phyla identified in wastewater were Proteobacteria, Bacteroidetes, Firmicutes, Chloroflexi, Actinobacteria, Spirochetes, Patesibacteria, Acidobacteria, and others including unknown microbes. The study showed the function of microbial communities essential for the oxidation and detoxifying of complex contaminants and design of effective remediation techniques for the re-use of polluted wastewater. Findings demonstrated that the ability of different classes of microbes to adapt and survive in metal-polluted wastewater irrespective of their relative distribution, as well as further attention can be provided to its use in the bioremediation process.


Assuntos
Microbiota , Águas Residuárias , Acidobacteria , Bactérias/genética , RNA Ribossômico 16S/genética
11.
Environ Res ; 194: 110664, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33400949

RESUMO

Antibiotic resistance is a global health emergency linked to unrestrained use of pharmaceutical and personal care products (PPCPs) as prophylactic agent and therapeutic purposes across various industries. Occurrence of pharmaceuticals are identified in ground water, surface water, soils, and wastewater treatment plants (WWTPs) in ng/L to µg/L concentration range. The prevalence of organic compounds including antimicrobial agents, hormones, antibiotics, preservatives, disinfectants, synthetic musks etc. in environment have posed serious health concerns. The aim of this review is to elucidate the major sources accountable for emergence of antibiotic resistance. For this purpose, variety of introductory sources and fate of PPCPs in aquatic environment including human and veterinary wastes, aquaculture and agriculture related wastes, and other anthropogenic activities have been discussed. Furthermore, genetic and enzymatic factors responsible for transfer and appearance of antibiotic resistance genes are presented. Ecotoxicity of PPCPs has been studied in environment in order to present risk imposed to human and ecological health. As per published literature reports, the removal of antibiotics and related traces being difficult, couples the possibility of emergence of antibiotic resistance and hence sustainability in global water resources. Therefore, research on environmental behavior and control strategies should be conducted along with assessing their chronic toxicity to identify potential human and ecological risks.


Assuntos
Cosméticos , Preparações Farmacêuticas , Poluentes Químicos da Água , Antibacterianos/toxicidade , Cosméticos/análise , Monitoramento Ambiental , Humanos , Prevalência , Águas Residuárias , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
12.
Bioresour Technol ; 320(Pt B): 124353, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33202343

RESUMO

This work aimed to study Bacillus sp. PS-6 assisted phytoremediation of metals from pulp and paper industry wastewater as a novel green technique for the removal of metals of wastewater. Results revealed that heavy metal (mg L-1) contents in wastewater were reduced after in-situ phytoremediation for Fe, Cu, Zn, Cd, Mn, Ni, Pb, and As. Phragmites communis showed higher potential for the enrichment of Fe, Cu, Zn, Cd, Mn, Ni, Pb, and As in its rhizomes, roots, and shoots compared to leaves. The strain produced indole acetic acid, siderophores, and hydrolytic and ligninolytic enzymes, and resulted in nutrients solubilization. Results offer potential basis for the removal of metals from pulp and paper industry wastewater at large scale and prevention of pollution.


Assuntos
Bacillus , Metais Pesados , Poluentes do Solo , Purificação da Água , Biodegradação Ambiental , Metais Pesados/análise , Propanolaminas , Poluentes do Solo/análise
13.
Bioresour Technol ; 319: 124147, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32992272

RESUMO

The aims of the study was the evaluation of phytoremediation potential by Eclipta alba (L) and Alternanthera philoxeroide (L) of pulp and paper mill waste after secondary treatment which a source of aquatic and soil pollution due to huge discharge of organometallic compounds per tone of paper production. The result revealed 50% reduction of pollution parameters after in-situ phytoremediation. The comparative analysis of metal and metalloids showed the highest accumulation of Fe (2251.24 ± 64.74) in both plants. The antioxidant activity, chlorophyll and carotenoid content were increased in E. alba (L.) and A. philoxeroide (L.) respectively. From the results, it was concluded that E. alba (L.) and A. philoxeroide (L.) could be effectively used for the removal of metals and metalloids from effluent and sludge of pulp and paper mill waste that may help to reduce adverse health effects of metal accumulation in humans and animals via their food chain.


Assuntos
Eclipta , Metaloides , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Resíduos Industriais/análise , Metais , Metais Pesados/análise , Poluentes do Solo/análise
14.
Heliyon ; 6(7): e04559, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32760841

RESUMO

The present manuscript has focused on the heavy metal; accumulation potential by common native plants i.e. Chenopodium album L., Ricinus communis, Ranunculus sceleratus, and Rumex dentatus growing on the disposed of pulp and paper mill effluent sludge. The sludge showed the abundance of benzene propanoic acid tert- butyldimethylsilyl ester, Octadecanoic acid, TMS, Hexadecanoic acid, TMS, cinnamic acid-α-phenyl-TMS ester, ß-sitosterol TMS, 4-mercaptobenzoic acid as residual complex organic compounds along with heavy metals Fe (98.30 mg/L-1), Zn (51.00 mg/L-1), Cu (3.21 mg/L-1), Cd (9.11 mg/L-1), Mn (18.27 mg/L-1), Ni (5.21 mg/L-1), (Hg 0.014 mg/L-1) which were above the prescribed limit of environmental standard. The complexation of organic compounds with heavy metal restricts the bioavailability of metals to plants. But the metal analysis in various parts of the plant showed a significant amount of metal accumulation. Further, histological observations of root tissue through TEM showed apparent deposition of metal granules near the cell wall and vacuole as adoption features of plants. But the variable concentration of metal accumulation in different parts by various plants indicated the variable potential of tested plants with various metals. This also indicated their metal bio-availability and movement to plant tissue. Further, their bioconcentration factor (BCF) and translocation factor (TF) > 1.0 indicated the hyperaccumulation tendency of plants Mn was accumulated maximum in leaves C. album (69.38 mg/kg-1) followed by Cu (25.75 mg/kg -1), As (23.20 mg/kg -1), Fe (20.90 mg/kg -1) and Pb was maximum accumulated (22.41 mg/kg -1) in R. cummunis leaves. The result revealed that arsenic has been accumulated in higher amount root, shoot and leaves of all tested plants. The metal accumulator plants showed phytoremediation potential also by reducing various pollution parameters after growth on sludge. These potential plants may be used as biotechnological tools for the eco-restoration of polluted sites.

15.
3 Biotech ; 10(7): 316, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32612900

RESUMO

The present paper aims to explore the rhizospheric bacterial communities associated with Saccharum arundinaceum grown on organometallic pollutants-rich hazardous distillery sludge. The sequence analysis of 16S rRNA V3-V4 hypervariable region with Illumina MiSeq platform showed 621,897 OTUs derived from rhizospheric and non-rhizospheric distillery sludge samples out of 1,191,014 and 901,757 sequences read, respectively. The major phyla detected in rhizospheric sludge sample were Proteobacteria (50%), Bacteriodetes (33%), Firmicutes (5%) Gemmatimonadetes (2%), Chloroflexi (2%), and Tenericutes (2%). The dominant three genera were detected as Rheinheimera (21%), Sphingobacterium (17%), and Idiomarina (8%). In addition, other minor genera such as uncultured Bacillus (4%), Acidothermus (4%), Bacillus (3%), Pseudomonas (2%), Flavobacterium (2%), uncultured bacterium (2%), Parapedobacter (2%), Alcanivorax (2%), Acholeplasma (2%), Hyphomonas (1%), and Aquamicrobium were also detected (1%) in rhizospheric sludge. Our results suggested that rhizospheric bacterial communities associated with S. arundinaceum were substantially different in richness, diversity, and relative abundance of taxa compared to non-rhizospheric sludge. Further, the comparative organic pollutant analysis from non-rhizospheric and rhizospheric sludge samples through GC-MS analysis revealed the disappearance of few compounds and generation of some compounds as new metabolic products by the activity of rhizospheric bacterial communities. The results of this study will be helpful in understanding the role of rhizospheric bacterial communities responsible for degradation and detoxification of complex organometallic waste and, thus, can help in designing appropriate phytoremediation studies for eco-restoration of polluted sites.

16.
Environ Sci Pollut Res Int ; 27(13): 14515-14528, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32043251

RESUMO

In this experimental study, seeds of wild tree species namely Acacia nilotica, Prosopis juliflora, Albizia lebbeck, and Leucaena leucocephala were explored as potential feedstocks for anaerobic digestion and compared with cattle manure which is a commonly used feedstock. These seeds occur abundantly as waste biomass in tropical and subtropical parts of Asia, Africa, and the USA. An experimental investigation was carried out in large 300-L anaerobic digesters under semi-continuous feed mode for 90 days. The average specific methane production yield observed was 0.208 Nm3/kg volatile solids (VS) for A. nilotica, 0.227 Nm3/kg VS for P. juliflora, 0.219 Nm3/kg VS for A. lebbeck and 0.210 Nm3/kg VS for L. leucocephala which was found to be higher than cattle manure's yield of 0.146 Nm3/kg VS. Experimental analysis revealed an average methane content of more than 52% for all the seeds and a total volatile solid mass removal efficiency of 41.60% for A. nilotica, 44.19% for P. juliflora, 43.76% for A. lebbeck, and 41.41% for L. leucocephala which was higher than 29.7% for cattle manure. The experimental investigations showed that they have a higher biogas production potential than cattle manure indicating their huge scope and suitability as alternative feedstocks, and their use can also mitigate the ecological risk seeds pose by growing into invasive trees.


Assuntos
Biocombustíveis , Árvores , África , Anaerobiose , Animais , Ásia , Reatores Biológicos , Bovinos , Esterco , Metano/análise
17.
Heliyon ; 6(2): e03170, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32095645

RESUMO

Ligninolytic enzymes play a key role in degradation and detoxification of lignocellulosic waste in environment. The major ligninolytic enzymes are laccase, lignin peroxidase, manganese peroxidase, and versatile peroxidase. The activities of these enzymes are enhanced by various mediators as well as some other enzymes (feruloyl esterase, aryl-alcohol oxidase, quinone reductases, lipases, catechol 2, 3-dioxygenase) to facilitate the process for degradation and detoxification of lignocellulosic waste in environment. The structurally laccase is isoenzymes with monomeric or dimeric and glycosylation levels (10-45%). This contains four copper ions of three different types. The enzyme catalyzes the overall reaction: 4 benzenediol + O2 to 4 benzosemiquinone + 2H2O. While, lignin peroxidase is a glycoprotein molecular mass of 38-46 kDa containing one mole of iron protoporphyrin IX per one mol of protein, catalyzes the H2O2 dependent oxidative depolymerization of lignin. The manganese peroxidase is a glycosylated heme protein with molecular mass of 40-50kDa. It depolymerizes the lignin molecule in the presence of manganese ion. The versatile peroxidase has broad range substrate sharing typical features of the manganese and lignin peroxidase families. Although ligninolytic enzymes have broad range of industrial application specially the degradation and detoxification of lignocellulosic waste discharged from various industrial activities, its large scale application is still limited due to lack of limited production. Further, the extremophilic properties of ligninolytic enzymes indicated their broad prospects in varied environmental conditions. Therefore it needs more extensive research for understanding its structure and mechanisms for broad range commercial applications.

18.
Aquat Toxicol ; 211: 202-216, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31029991

RESUMO

The pulp paper industries release wastewater containing very complex organic and inorganic pollutants. These pollutants are discharged mainly pulping and bleaching process during paper manufacturing. The main gaseous pollutants hydrogen sulfides, sodium sulfide, methyl mercaptan, sulfur, and chlorine dioxide is reported for chronic, respiratory disorder and irritation to skin, eyes and cardiac problem along with nausea and headache. The major inorganic pollutants include ferrous, copper, zinc, nickel, and magnesium, which is reported for neurotoxicity, toxic to juvenile channel catfish (Ictalurus punctatus) and Accumulation to gill > liver > ovary > muscle. The detected major organic and inorganic pollutants are hexadecanoic acids, octacosane, ß-sitosterol trimethylsilyl ether, 1-tetradecane, 2-methoxy phenol, trichlorocatechol, tetrachlorocatechol, chlorophenols, chloroguaiacols, chlorosyringols, chlorocatechols, terpenes, methanol, phenol, alkylated phenols, decalone, benzoic acid, abietic acid, and dehydroabietic acid. Several of these compounds are reported as endocrine-disrupting chemicals (EDCs). Therefore, direct toxicity of effluent to the reproductive system in aquatic flora and fauna are reported. Several reports have highlighted reduced gonad size, change in secondary sexual character, delayed maturity and suppression of sex hormone in fish rainbow trout (Oncorhynchus mykiss) and mosquitofish (Gambusia holbrooki) further the in-vitro studies of organic compounds on fish, Salmonella typhimurium, Vibrio fischeri, and Saccharomyces have shown inhibition in growth and luminescence properties. The presence of organic and inorganic pollutants in pulp paper industry wastewater causes phytotoxicity chromosomal aberration in Allium cepa. Thus the manuscript has concluded that detected pollutants produced foul odors and cause hermaphroditism in fish, hepatotoxicity and mutagenic effect. In addition, the growth of coliform bacteria in River and other aquatic resources has been reported due to contamination of PPI effluent. The studies also highlighted the presence of tannins, chlorophenols, dioxins, furans, biocide, fatty acids, and resin acids along with chlorolignine compounds as persistent organic pollutants (POP), which needs special attention for pollution prevention of rivers, lakes and other aquatic resources.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Resíduos Industriais/efeitos adversos , Papel , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Organismos Aquáticos/metabolismo
19.
Bioresour Technol ; 272: 611-615, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30385029

RESUMO

Rising rate of MSW generation and unscientific disposal in the open dumping sites are responsible for emission of high concentrations of methane in developing countries. IPCC Default method (DM), First-order decay (FOD) and LandGEM were used to estimate methane emissions from the unengineered landfill sites of Delhi-Okhla, Bhalswa and Ghazipur between 1984 and 2015. During the period, the total CH4 emissions was found to be 1288.99, 311.18, 779.32 Gg from the 3 landfill sites of Delhi as predicted by DM, FOD and LandGEM respectively. The energy generation potential from methane for the year 2015 was found to vary from 4.16 × 108 to 9.86 × 108 MJ for Ghazipur, 2.08 × 108 to 4.06 × 108 MJ for Okhla and 3.42 × 108 to 8.11 × 108 MJ for Bhalswa. Efficient utilization of methane from the landfills as an energy source can be a sustainable waste management option.


Assuntos
Fontes Geradoras de Energia , Metano/análise , Resíduos Sólidos/análise , Instalações de Eliminação de Resíduos , Índia , Fenômenos Físicos
20.
Environ Monit Assess ; 190(10): 581, 2018 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-30206720

RESUMO

The safe disposal of pulp and paper mill effluent is still a threat to the environment due to the presence of several unknown organic pollutants. The comparative physico-chemical analysis of pulp and paper mill effluent-contaminated sediment (PPECS) of site 1 and site 2 showed that the sediment had an alkaline nature and was loaded with several organic pollutants and heavy metals. SEM-EDX examination showed a porous structure with a heterogeneous distribution of particles, allowing the adsorption of metal and other complex organic ions. FTIR analysis depicted the presence of a variety of functional groups, i.e., alkyl halides, phenolics, and lignin, in the contaminated sediment. GC-MS analysis showed the major presence of organic pollutants, i.e., 2-methyl-4-keto-2-pentan-2-ol and 3,7-dioxa-2,8-disilanonane,2,2,8,8-tetramethyl-5-[(trimethylsilyl)oxy], in the site 1 sediment contaminated with pulp and paper mill waste, while 2-methyl-4-keto-2-trimethylsiloxypentane, 4-ethyl-2-methoxyphenol, ethyl-2-octynoate, cis-9-hexadecenoic acid, and octadecenoic acid were detected in the site 2 sediment contaminated with pulp and paper mill waste. The genotoxicity of PPECS determined by examining Allium cepa root cell division showed chromosomal aberration. In this study, several compounds that have not been reported before were identified.


Assuntos
Monitoramento Ambiental/métodos , Resíduos Industriais/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Allium/efeitos dos fármacos , Índia , Lignina/análise , Metais Pesados/análise , Papel , Phaseolus/efeitos dos fármacos , Fenóis/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Triticum/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
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